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Sample records for affinity choline uptake

  1. Choline uptake in Agrobacterium tumefaciens by the high-affinity ChoXWV transporter.

    PubMed

    Aktas, Meriyem; Jost, Kathinka A; Fritz, Christiane; Narberhaus, Franz

    2011-10-01

    Agrobacterium tumefaciens is a facultative phytopathogen that causes crown gall disease. For successful plant transformation A. tumefaciens requires the membrane lipid phosphatidylcholine (PC), which is produced via the methylation and the PC synthase (Pcs) pathways. The latter route is dependent on choline. Although choline uptake has been demonstrated in A. tumefaciens, the responsible transporter(s) remained elusive. In this study, we identified the first choline transport system in A. tumefaciens. The ABC-type choline transporter is encoded by the chromosomally located choXWV operon (ChoX, binding protein; ChoW, permease; and ChoV, ATPase). The Cho system is not critical for growth and PC synthesis. However, [14C]choline uptake is severely reduced in A. tumefaciens choX mutants. Recombinant ChoX is able to bind choline with high affinity (equilibrium dissociation constant [KD] of ≈2 μM). Since other quaternary amines are bound by ChoX with much lower affinities (acetylcholine, KD of ≈80 μM; betaine, KD of ≈470 μM), the ChoXWV system functions as a high-affinity transporter with a preference for choline. Two tryptophan residues (W40 and W87) located in the predicted ligand-binding pocket are essential for choline binding. The structural model of ChoX built on Sinorhizobium meliloti ChoX resembles the typical structure of substrate binding proteins with a so-called "Venus flytrap mechanism" of substrate binding. PMID:21803998

  2. Inhibition of high affinity choline uptake by N-allyl-3-quinuclidinol

    SciTech Connect

    Asermely, K.E.; O'Neill, J.J.

    1986-03-01

    The peripheral actions of N-allyl-3-quinuclidinol (N-Al-3-OHQ) on high affinity choline uptake (HAChU) on rat phrenic nerve diaphragm are described. Endplate regions (EPA) identified by the Koelle histochemical techniques for acetylcholinesterase, were dissected from adult rat hemidiaphragms and placed in cold Krebs solution (pH-7.35). All measurements of HAChU were at 37/sup 0/C in buffers containing tritium choline (5 ..mu..M 0.124 ..mu..C/mmole) at intervals of 1, 2, 4, 8, 15 and 30 min. Tissues were washed 3x, digested in 1N NaOH and counted for tritium in Chaikoff's solution. All data are expressed as pmole Ch/g wet weight. Comparison between EPA and non-EPA tissue demonstrate HAChU and slow choline diffusion, respectively. Steady state is observed in 15 min. N-Al-3-OHQ produces 15% inhibition at 5 x 10/sup -5/ M compared with 50% inhibition on brain synaptosomes. At 5 x 10/sup -4/ M N-Al-3-OHQ, 30% inhibition is observed. Attempts to deplete ACh by pre-stimulation with high K/sup +/-ion (25 mM) were unsuccessful; tissue /sup 3/H-choline uptake appeared to oscillate over a 30 min period.

  3. Corticotropin-releasing factor antagonist blocks microwave-induced decreases in high-affinity choline uptake in the rat brain

    SciTech Connect

    Lai, H.; Carino, M.A.; Horita, A.; Guy, A.W. )

    1990-10-01

    Acute (45-min) irradiation with pulsed low-level microwaves (2450-MHz, 2 microseconds pulses at 500 pps, average power density of 1 mW/cm2, whole-body average specific absorption rate of 0.6 W/kg) decreased sodium-dependent high-affinity choline uptake (HACU) activity in the frontal cortex and hippocampus of the rat. These effects were blocked by pretreating the animals before exposure with intracerebroventricular injection of the specific corticotropin-releasing factor (CRF) receptor antagonist, alpha-helical-CRF9-41 (25 micrograms). Similar injection of the antagonist had no significant effect on HACU in the brain of the sham-exposed rats. These data suggest that low-level microwave irradiation activates CRF in the brain, which in turn causes the changes in central HACU.

  4. High-affinity choline uptake and acetylcholine-metabolizing enzymes in CNS white matter. A quantitative study.

    PubMed

    Hassel, Bjørnar; Solyga, Volker; Lossius, Andreas

    2008-12-01

    The presence of nicotinic and muscarinic receptors suggests the occurrence of cholinergic neurotransmission in white matter; however no quantitative information exists on acetylcholine formation and breakdown in white matter. We compared white structures of pig brain (fimbria, corpus callosum, pyramidal tracts, and occipital white matter) to gray structures (temporal, parietal and cerebellar cortices, hippocampus, and caudate) and found that sodium-dependent, high-affinity choline uptake in white structures was 25-31% of that in hippocampus. White matter choline acetyltransferase activity was 10-50% of the hippocampal value; the highest activity was found in fimbria. Acetylcholine esterase activity in white structures was 20-25% of that in hippocampus. The caudate, which is rich in cholinergic interneurons, gave values for all three parameters that were 2.8-4 times higher than in hippocampus. The results suggest a certain capacity for cholinergic neurotransmission in central nervous white matter. The white matter activity of pyruvate dehydrogenase, which provides acetyl-CoA for acetylcholine synthesis, ranged between 33 and 50% of the hippocampal activity; the activity in the caudate was similar to that in hippocampus and the other gray structures, which was true also for other enzymes of glucose metabolism: hexokinase, phosphoglucomutase, and glucose-6-phosphate dehydrogenase. Acetylcholine esterase activity in white matter was inhibited by the nerve agent soman, which may help explain the reported deleterious effect of soman on white matter. Further, this finding suggests that acetylcholine esterase inhibitors used in Alzheimer's disease may have an effect in white matter. PMID:18674580

  5. OusB, a Broad-Specificity ABC-Type Transporter from Erwinia chrysanthemi, Mediates Uptake of Glycine Betaine and Choline with a High Affinity

    PubMed Central

    Choquet, Gwénaëlle; Jehan, Nathalie; Pissavin, Christine; Blanco, Carlos; Jebbar, Mohamed

    2005-01-01

    The ability of Erwinia chrysanthemi to cope with environments of elevated osmolality is due in part to the transport and accumulation of osmoprotectants. In this study we have identified a high-affinity glycine betaine and choline transport system in E. chrysanthemi. By using a pool of Tn5-B21 ousA mutants, we isolated a mutant that could grow in the presence of a toxic analogue of glycine betaine (benzyl-glycine betaine) at high osmolalities. This mutant was impaired in its ability to transport all effective osmoprotectants in E. chrysanthemi. The DNA sequence of the regions flanking the transposon insertion site revealed three chromosomal genes (ousVWX) that encode components of an ABC-type transporter (OusB): OusV (ATPase), OusW (permease), and OusX (periplasmic binding protein). The OusB components showed a significant degree of sequence identity to components of ProU from Salmonella enterica serovar Typhimurium and Escherichia coli. OusB was found to restore the uptake of glycine betaine and choline through functional complementation of an E. coli mutant defective in both ProU and ProP osmoprotectant uptake systems. Competition experiments demonstrated that choline, dimethylsulfoniacetate, dimethylsulfoniopropionate, and ectoine were effective competitors for OusB-mediated betaine transport but that carnitine, pipecolate, and proline were not effective. In addition, the analysis of single and double mutants showed that OusA and OusB were the only osmoprotectant transporters operating in E. chrysanthemi. PMID:16000740

  6. Uptake of (N-Me-3H)-choline by synaptosomes from the central nervous system of Locusta migratoria

    SciTech Connect

    Breer, H.

    1982-03-01

    The accumulation of 3H-choline by isolated synaptosomes from the central nervous system of locust was studied at concentrations varying from 0.05 to 40 microM. Kinetic analysis of the saturable process revealed a high-affinity and a low-affinity system. The high-affinity uptake was competitively inhibited by hemicholinium-3 and was absolutely dependent on external sodium. Elevated potassium concentrations inhibited choline uptake. The choline uptake by insect synaptosomes was found to be remarkably resistant to a variety of metabolic inhibitors. The reduced choline uptake under depolarizing conditions (high potassium concentration or veratridine) in the absence of calcium implies that electrochemical gradients are important for high-affinity choline uptake. Depolarization of preloaded synaptosomes under appropriate conditions resulted in a significant release of newly accumulated choline radioactivity.

  7. Uptake of free choline by isolated perfused rat liver.

    PubMed Central

    Zeisel, S H; Story, D L; Wurtman, R J; Brunengraber, H

    1980-01-01

    The uptake of free choline by isolated perfused rat liver was characterized. A saturable uptake mechanism [Ka = 0.17 +/- 0.07 mM (SD); Vmax = 0.84 +/- 0.16 mumol/min X g dry weight] and a nonsaturable mechanism (through which uptake is proportional to choline concentration in the perfusate) were identified. Most of the choline transported into hepatocytes was converted to betaine, phosphorylcholine, or lecithin. Free choline also accumulated within the intracellular space, suggesting that choline oxidase activity does not always limit choline's uptake by the liver. PMID:6933493

  8. Phospholipase A2 and 3H-hemicholinium-3 binding sites in rat brain: A potential second-messenger role for fatty acids in the regulation of high-affinity choline uptake

    SciTech Connect

    Saltarelli, M.D.; Yamada, K.; Coyle, J.T. )

    1990-01-01

    The involvement of phospholipase A2 (PLA2) and fatty acid release in the regulation of sodium-dependent high-affinity choline uptake in rat brain was assessed in vitro through the use of the specific binding of 3H-hemicholinium-3 (3H-HCh-3). Addition of arachidonic acid and other unsaturated fatty acids to rat striatal membranes in vitro resulted in a dose-dependent, temperature-independent activation of 3H-HCh-3 binding. Scatchard analysis revealed that these changes in binding result from a 2-fold increase in the affinity and capacity of 3H-HCh-3 binding. Saturated fatty acids, lysophospholipids, and phospholipids did not affect specific 3H-HCh-3 binding. Addition of defatted BSA to membranes, which had been treated previously with arachidonic acid, completely reversed the increase in specific 3H-HCh-3 binding. However, several inhibitors of fatty acid metabolism, including nordihydroguaiaretic acid, indomethacin, catalase, and superoxide dismutase, did not alter arachidonic acid-induced changes in 3H-HCh-3 binding, suggesting that unsaturated fatty acids, and not their metabolites, are directly responsible for the observed activation of specific 3H-HCh-3 binding. Additionally, unsaturated fatty acids dose-dependently inhibited high-affinity 3H-choline uptake in rat striatal synaptosomes, apparently due to the disruption of synaptosomal integrity. The phospholipase A2 inhibitors quinacrine hydrochloride, trifluoperazine, and 4-bromophenacylbromide dose-dependently inhibited potassium depolarization-induced activation of specific 3H-HCh-3 binding in slices of rat brain in vitro. Similarly, both quinacrine and trifluoperazine inhibited the metabolism of phospholipids and the release of fatty acids evoked by either elevated KCl or calcium ionophore A23187.

  9. Functional analysis of [methyl-(3)H]choline uptake in glioblastoma cells: Influence of anti-cancer and central nervous system drugs.

    PubMed

    Taguchi, Chiaki; Inazu, Masato; Saiki, Iwao; Yara, Miki; Hara, Naomi; Yamanaka, Tsuyoshi; Uchino, Hiroyuki

    2014-04-01

    Positron emission tomography (PET) and PET/computed tomography (PET-CT) studies with (11)C- or (18)F-labeled choline derivatives are used for PET imaging in glioblastoma patients. However, the nature of the choline transport system in glioblastoma is poorly understood. In this study, we performed a functional characterization of [methyl-(3)H]choline uptake and sought to identify the transporters that mediate choline uptake in the human glioblastoma cell lines A-172 and U-251MG. In addition, we examined the influence of anti-cancer drugs and central nervous system drugs on the transport of [methyl-(3)H]choline. High- and low-affinity choline transport systems were present in A-172 cells, U-251MG cells and astrocytes, and these were Na(+)-independent and pH-dependent. Cell viability in A-172 cells was not affected by choline deficiency. However, cell viability in U-251MG cells was significantly inhibited by choline deficiency. Both A-172 and U-251MG cells have two different choline transporters, choline transporter-like protein 1 (CTL1) and CTL2. In A-172 cells, CTL1 is predominantly expressed, whereas in U-251MG cells, CTL2 is predominantly expressed. Treatment with anti-cancer drugs such as cisplatin, etoposide and vincristine influenced [methyl-(3)H]choline uptake in U-251MG cells, but not A-172 cells. Central nervous system drugs such as imipramine, fluvoxamine, paroxetine, reboxetine, citalopram and donepezil did not affect cell viability or [methyl-(3)H]choline uptake. The data presented here suggest that CTL1 and CTL2 are functionally expressed in A-172 and U-251MG cells and are responsible for [methyl-(3)H]choline uptake that relies on a directed H(+) gradient as a driving force. Furthermore, while anti-cancer drugs altered [methyl-(3)H]choline uptake, central nervous system drugs did not affect [methyl-(3)H]choline uptake. PMID:24530235

  10. Pseudomonas syringae BetT Is a Low-Affinity Choline Transporter That Is Responsible for Superior Osmoprotection by Choline over Glycine Betaine▿

    PubMed Central

    Chen, Chiliang; Beattie, Gwyn A.

    2008-01-01

    The plant pathogen Pseudomonas syringae derives better osmoprotection from choline than from glycine betaine, unlike most bacteria that have been characterized. In this report, we identified a betaine/carnitine/choline family transporter (BCCT) in P. syringae pv. tomato strain DC3000 that mediates the transport of choline and acetylcholine. This transporter has a particularly low affinity (Km of 876 μM) and high capacity (Vmax of 80 nmol/min/mg of protein) for choline transport relative to other known BCCTs. Although BetT activity increased in response to hyperosmolarity, BetT mediated significant uptake under low-osmolarity conditions, suggesting a role in transport for both osmoprotection and catabolism. Growth studies with mutants deficient in BetT and other choline transporters demonstrated that BetT was responsible for the superior osmoprotection conferred to P. syringae by choline over glycine betaine when these compounds were provided at high concentrations (>100 μM). These results suggest that P. syringae has evolved to survive in relatively choline-rich habitats, a prediction that is supported by the common association of P. syringae with plants and the widespread production of choline, but genus- and species-specific production of glycine betaine, by plants. Among the three putative BCCT family transporters in Pseudomonas aeruginosa and six in Pseudomonas putida, different transporters were predicted to function based on similarity to Escherichia coli BetT than to P. syringae BetT. Functional P. putida and P. aeruginosa transporters were identified, and their possession of a long C-terminal tail suggested an osmoregulatory function for this tail; this function was confirmed for P. syringae BetT using deletion derivatives. PMID:18156257

  11. Effects of low-level microwave irradiation on hippocampal and frontal cortical choline uptake are classically conditionable

    SciTech Connect

    Lai, H.; Horita, A.; Chou, C.K.; Guy, A.W.

    1987-08-01

    In previous research, we found that sodium-dependent high-affinity choline uptake in the hippocampus and frontal cortex of the rat was lowered after acute (45 min) exposure to low-level 2450-MHz pulsed microwaves (power density 1 mW/cm2; average whole body specific absorption rate, 0.6 W/kg; 2 mu sec pulses, 500 pps). In the present experiment, we investigated developments of tolerance and classical conditioning to these effects of microwaves. Rats were exposed to microwaves in cylindrical waveguides in 10 daily sessions (45 min per session). In an 11th session, we subjected the rats to either microwave (study of tolerance) or sham exposure (study of conditioned effect) for 45 min, and immediately measured choline uptake in the hippocampus and frontal cortex. We found that tolerance, a decrease in response to microwaves, developed to the effect of microwaves on choline uptake in the hippocampus, but not in the frontal cortex. Conditioned effects were also observed: an increase in choline uptake in the hippocampus and a decrease in uptake in the frontal cortex. These data suggest that the effects of microwaves on choline uptake in the hippocampus and frontal cortex are classically conditionable, probably to cues in the exposure environment.

  12. Insulin Regulates the Activity of the High-Affinity Choline Transporter CHT.

    PubMed

    Fishwick, Katherine J; Rylett, R Jane

    2015-01-01

    Studies in humans and animal models show that neuronal insulin resistance increases the risk of developing Alzheimer's Disease (AD), and that insulin treatment may promote memory function. Cholinergic neurons play a critical role in cognitive and attentional processing and their dysfunction early in AD pathology may promote the progression of AD pathology. Synthesis and release of the neurotransmitter acetylcholine (ACh) is closely linked to the activity of the high-affinity choline transporter protein (CHT), but the impact of insulin receptor signaling and neuronal insulin resistance on these aspects of cholinergic function are unknown. In this study, we used differentiated SH-SY5Y cells stably-expressing CHT proteins to study the effect of insulin signaling on CHT activity and function. We find that choline uptake activity measured after acute addition of 20 nM insulin is significantly lower in cells that were grown for 24 h in media containing insulin compared to cells grown in the absence of insulin. This coincides with loss of ability to increase phospho-Protein Kinase B (PKB)/Akt levels in response to acute insulin stimulation in the chronic insulin-treated cells. Inhibition of phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3-kinase) in cells significantly lowers phospho-PKB/Akt levels and decreases choline uptake activity. We show total internal reflection microscopy (TIRF) imaging of the dynamic movement of CHT proteins in live cells in response to depolarization and drug treatments. These data show that acute exposure of depolarized cells to insulin is coupled to transiently increased levels of CHT proteins at the cell surface, and that this is attenuated by chronic insulin exposure. Moreover, prolonged inhibition of PI3-kinase results in enhanced levels of CHT proteins at the cell surface by decreasing their rate of internalization. PMID:26161852

  13. Insulin Regulates the Activity of the High-Affinity Choline Transporter CHT

    PubMed Central

    Fishwick, Katherine J.; Rylett, R. Jane

    2015-01-01

    Studies in humans and animal models show that neuronal insulin resistance increases the risk of developing Alzheimer’s Disease (AD), and that insulin treatment may promote memory function. Cholinergic neurons play a critical role in cognitive and attentional processing and their dysfunction early in AD pathology may promote the progression of AD pathology. Synthesis and release of the neurotransmitter acetylcholine (ACh) is closely linked to the activity of the high-affinity choline transporter protein (CHT), but the impact of insulin receptor signaling and neuronal insulin resistance on these aspects of cholinergic function are unknown. In this study, we used differentiated SH-SY5Y cells stably-expressing CHT proteins to study the effect of insulin signaling on CHT activity and function. We find that choline uptake activity measured after acute addition of 20 nM insulin is significantly lower in cells that were grown for 24 h in media containing insulin compared to cells grown in the absence of insulin. This coincides with loss of ability to increase phospho-Protein Kinase B (PKB)/Akt levels in response to acute insulin stimulation in the chronic insulin-treated cells. Inhibition of phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3-kinase) in cells significantly lowers phospho-PKB/Akt levels and decreases choline uptake activity. We show total internal reflection microscopy (TIRF) imaging of the dynamic movement of CHT proteins in live cells in response to depolarization and drug treatments. These data show that acute exposure of depolarized cells to insulin is coupled to transiently increased levels of CHT proteins at the cell surface, and that this is attenuated by chronic insulin exposure. Moreover, prolonged inhibition of PI3-kinase results in enhanced levels of CHT proteins at the cell surface by decreasing their rate of internalization. PMID:26161852

  14. Uptake and output of various forms of choline by organs of the conscious chronically catheterized sheep.

    PubMed Central

    Robinson, B S; Snoswell, A M; Runciman, W B; Upton, R N

    1984-01-01

    The net uptake and output of plasma unesterified choline, glycerophosphocholine, phosphocholine and lipid choline by organs of the conscious chronically catheterized sheep were measured. There was significant production of plasma unesterified choline by the upper- and lower-body regions and the alimentary tract and uptake by the liver, lungs and kidneys. The upper- and lower-body regions drained by the venae cavae provided the bulk (about 82%) of the total body venous return of plasma unesterified choline. Production of plasma unesterified choline by the alimentary tract was approximately balanced by the plasma unesterified choline taken up by the liver, and was almost equal to the amount of choline secreted in the bile. There was a considerable amount of glycerophosphocholine in the liver and there was production of plasma glycerophosphocholine by the liver and uptake by the lungs and kidneys. Glycerophosphocholine was higher in the plasma of sheep than in that of rats. Plasma phosphocholine was produced by the alimentary tract and kidneys. There was production of plasma lipid choline by the upper- and lower-body regions drained by the venae cavae. The results suggest that the sheep synthesizes substantial amounts of choline in ectrahepatic tissues and has the capacity for extensive retention and recycling of bile choline. These observations, coupled with a slow turnover of the endogenous choline body pool, explain the low requirement of sheep for dietary choline in contrast with non-ruminant species. PMID:6696739

  15. The uptake of [14C]choline into synaptosomes in vitro

    PubMed Central

    Marchbanks, R. M.

    1968-01-01

    1. The uptake of [14C]choline into synaptosomes in vitro was investigated by a gel-filtration method. Synaptosomes incubated in a medium fortified with glucose and succinate rapidly take up [14C]choline. 2. A substantial proportion of the radioactivity taken up can be released by osmotic shock, and is recoverable as choline on a thin-layer chromatogram. This suggests that choline is taken up across the limiting membrane into the cytoplasmic compartment of the synaptosome. 3. The concentration of choline in the synaptosome has a dependence on the external concentration of choline that is similar to that in erythrocytes and mouse cerebral-cortex slices. The choline influx has two components, one that is linear and one that is saturable with increasing choline concentration. 4. Omission of Na+ from the incubation medium, or addition of 100mm-K+, inhibits choline uptake. Hemicholinium no. 3 is a powerful inhibitor of the choline uptake. 5. The similarity of the choline-uptake process in synaptosomes to that in erythrocytes and cortex slices indicates that the synaptosome limiting membrane is functionally competent in this respect. PMID:5701684

  16. Carbon-11 choline: synthesis, purification, and brain uptake inhibition by 2-dimethylaminoethanol

    SciTech Connect

    Rosen, M.A.; Jones, R.M.; Yano, Y.; Budinger, T.F.

    1985-12-01

    We report an improved method for the synthesis and purification of (11C)methylcholine from the precursors (11C)methyliodide and 2-dimethylaminoethanol (deanol). Preparation time, including purification, is 35 min postbombardment. Forty millicuries of purified injectable (11C)choline were produced with a measured specific activity of greater than 300 Ci/mmol and a radiochemical purity greater than 98%. The decay corrected radiochemical yield for the synthesis and purification was approximately 50%. Residual precursor deanol, which inhibits brain uptake of choline, is removed by a rapid preparative high performance liquid chromatography (HPLC) method using a reverse phase cyano column with a biologically compatible 100% water eluent. Evaporation alone did not completely remove the deanol precursor. Brain uptake of the (11C)choline product was six times greater after HPLC removal of deanol because doses of less than 1 microgram/kg significantly inhibit (14C)choline brain uptake.

  17. Comparative effects of aluminum and ouabain on synaptosomal choline uptake, acetylcholine release and (Na+/K+)ATPase.

    PubMed

    Silva, Virgília S; Nunes, M Alexandra; Cordeiro, J Miguel; Calejo, Ana I; Santos, Sofia; Neves, Paulo; Sykes, António; Morgado, Fernando; Dunant, Yves; Gonçalves, Paula P

    2007-07-17

    Closing the gap between adverse health effects of aluminum and its mechanisms of action still represents a huge challenge. Cholinergic dysfunction has been implicated in neuronal injury induced by aluminum. Previously reported data also indicate that in vivo and in vitro exposure to aluminum inhibits the mammalian (Na(+)/K(+))ATPase, an ubiquitous plasma membrane pump. This study was undertaken with the specific aim of determining whether in vitro exposure to AlCl(3) and ouabain, the foremost utilized selective inhibitor of (Na(+)/K(+))ATPase, induce similar functional modifications of cholinergic presynaptic nerve terminals, by comparing their effects on choline uptake, acetylcholine release and (Na(+)/K(+))ATPase activity, on subcellular fractions enriched in synaptic nerve endings isolated from rat brain, cuttlefish optic lobe and torpedo electric organ. Results obtained show that choline uptake by rat synaptosomes was inhibited by submillimolar AlCl(3), whereas the amount of choline taken up by synaptosomes isolated from cuttlefish and torpedo remained unchanged. Conversely, choline uptake was reduced by ouabain to a large extent in all synaptosomal preparations analyzed. In contrast to ouabain, which modified the K(+) depolarization evoked release of acetylcholine by rat, cuttlefish and torpedo synaptosomal fractions, AlCl(3) induced reduction of stimulated acetylcholine release was only observed when rat synaptosomes were challenged. Finally, it was observed that the aluminum effect on cuttlefish and torpedo synaptosomal (Na(+)/K(+))ATPase activity was slight when compared to its inhibitory action on mammalian (Na(+)/K(+))ATPase. In conclusion, inhibition of (Na(+)/K(+))ATPase by AlCl(3) and ouabain jeopardized the high-affinity (Na(+)-dependent, hemicholinium-3 sensitive) uptake of choline and the Ca(2+)-dependent, K(+) depolarization evoked release of acetylcholine by rat, cuttlefish and torpedo synaptosomal fractions. The effects of submillimolar AlCl(3

  18. The human organic cation transporter OCT1 mediates high affinity uptake of the anticancer drug daunorubicin.

    PubMed

    Andreev, Emil; Brosseau, Nicolas; Carmona, Euridice; Mes-Masson, Anne-Marie; Ramotar, Dindial

    2016-01-01

    Anthracyclines such as daunorubicin are anticancer agents that are transported into cells, and exert cytotoxicity by blocking DNA metabolism. Although there is evidence for active uptake of anthracyclines into cells, the specific transporter involved in this process has not been identified. Using the high-grade serous ovarian cancer cell line TOV2223G, we show that OCT1 mediated the high affinity (Km ~ 5 μM) uptake of daunorubicin into the cells, and that micromolar amounts of choline completely abolished the drug entry. OCT1 downregulation by shRNA impaired daunorubicin uptake into the TOV2223G cells, and these cells were significantly more resistant to the drug in comparison to the control shRNA. Transfection of HEK293T cells, which accommodated the ectopic expression of OCT1, with a plasmid expressing OCT1-EYFP showed that the transporter was predominantly localized to the plasma membrane. These transfected cells exhibited an increase in the uptake of daunorubicin in comparison to control cells transfected with an empty EYFP vector. Furthermore, a variant of OCT1, OCT1-D474C-EYFP, failed to enhance daunorubicin uptake. This is the first report demonstrating that human OCT1 is involved in the high affinity transport of anthracyclines. We postulate that OCT1 defects may contribute to the resistance of cancer cells treated with anthracyclines. PMID:26861753

  19. The human organic cation transporter OCT1 mediates high affinity uptake of the anticancer drug daunorubicin

    PubMed Central

    Andreev, Emil; Brosseau, Nicolas; Carmona, Euridice; Mes-Masson, Anne-Marie; Ramotar, Dindial

    2016-01-01

    Anthracyclines such as daunorubicin are anticancer agents that are transported into cells, and exert cytotoxicity by blocking DNA metabolism. Although there is evidence for active uptake of anthracyclines into cells, the specific transporter involved in this process has not been identified. Using the high-grade serous ovarian cancer cell line TOV2223G, we show that OCT1 mediated the high affinity (Km ~ 5 μM) uptake of daunorubicin into the cells, and that micromolar amounts of choline completely abolished the drug entry. OCT1 downregulation by shRNA impaired daunorubicin uptake into the TOV2223G cells, and these cells were significantly more resistant to the drug in comparison to the control shRNA. Transfection of HEK293T cells, which accommodated the ectopic expression of OCT1, with a plasmid expressing OCT1-EYFP showed that the transporter was predominantly localized to the plasma membrane. These transfected cells exhibited an increase in the uptake of daunorubicin in comparison to control cells transfected with an empty EYFP vector. Furthermore, a variant of OCT1, OCT1-D474C-EYFP, failed to enhance daunorubicin uptake. This is the first report demonstrating that human OCT1 is involved in the high affinity transport of anthracyclines. We postulate that OCT1 defects may contribute to the resistance of cancer cells treated with anthracyclines. PMID:26861753

  20. Cholinergic activation of the murine trachealis muscle via non-vesicular acetylcholine release involving low-affinity choline transporters.

    PubMed

    Nassenstein, Christina; Wiegand, Silke; Lips, Katrin S; Li, Guanfeng; Klein, Jochen; Kummer, Wolfgang

    2015-11-01

    In addition to quantal, vesicular release of acetylcholine (ACh), there is also non-quantal release at the motor endplate which is insufficient to evoke postsynaptic responses unless acetylcholinesterase (AChE) is inhibited. We here addressed potential non-quantal release in the mouse trachea by organ bath experiments and (immuno)histochemical methods. Electrical field stimulation (EFS) of nerve terminals elicited tracheal constriction that is largely due to ACh release. Classical enzyme histochemistry demonstrated acetylcholinesterase (AChE) activity in nerve fibers in the muscle and butyrylcholinesterase (BChE) activity in the smooth muscle cells. Acute inhibition of both esterases by eserine significantly raised tracheal tone which was fully sensitive to atropine. This effect was reduced, but not abolished, in AChE, but not in BChE gene-deficient mice. The eserine-induced increase in tracheal tone was unaffected by vesamicol (10(-5)M), an inhibitor of the vesicular acetylcholine transporter, and by corticosterone (10(-4)M), an inhibitor of organic cation transporters. Hemicholinium-3, in low concentrations an inhibitor of the high-affinity choline transporter-1 (CHT1), completely abrogated the eserine effects when applied in high concentrations (10(-4)M) pointing towards an involvement of low-affinity choline transporters. To evaluate the cellular sources of non-quantal ACh release in the trachea, expression of low-affinity choline transporter-like family (CTL1-5) was evaluated by RT-PCR analysis. Even though these transporters were largely abundant in the epithelium, denudation of airway epithelial cells had no effect on eserine-induced tracheal contraction, indicating a non-quantal release of ACh from non-epithelial sources in the airways. These data provide evidence for an epithelium-independent non-vesicular, non-quantal ACh release in the mouse trachea involving low-affinity choline transporters. PMID:26278668

  1. Potassium activation of [3H]-choline accumulation by isolated sympathetic ganglia of the rat.

    PubMed Central

    Higgins, A. J.; Neal, M. J.

    1982-01-01

    1 The effect of K-depolarization on the uptake of low and high concentrations of [3H]-choline by isolated superior sympathetic ganglia of the rat has been studied. 2 In unstimulated ganglia, the uptake of [3H]-choline (0.1 microM) ('high affinity uptake') was unaffected by denervation or by hemicholinium-3 (HC-3), suggesting uptake by structures other than cholinergic nerve terminals. 3 K-depolarization of the ganglia increased [3H]-choline accumulation by the high affinity uptake process but in contrast the 'low affinity' accumulation of [3H]-choline (100 microM) was decreased. 4 The K-activated, 'high affinity' component of choline uptake was highly sodium-dependent, inhibited by HC-3, and was abolished by denervation. 5 In incubation conditions designed to prevent transmitter release (Ca-free medium and high-Mg medium), the K-activated uptake of [3H]-choline was abolished. 6 It is concluded that in unstimulated ganglia, there is little choline uptake by nerve terminals. However, when the terminals are depolarized, choline uptake is increased by the activation of a sodium-dependent, HC-3-sensitive transport process. The activation of this uptake process is apparently associated with the release of acetylcholine from the terminals, or by changes in ionic fluxes, and not by the depolarization per se. PMID:7150866

  2. Impaired Presynaptic High-Affinity Choline Transporter Causes a Congenital Myasthenic Syndrome with Episodic Apnea.

    PubMed

    Bauché, Stéphanie; O'Regan, Seana; Azuma, Yoshiteru; Laffargue, Fanny; McMacken, Grace; Sternberg, Damien; Brochier, Guy; Buon, Céline; Bouzidi, Nassima; Topf, Ana; Lacène, Emmanuelle; Remerand, Ganaelle; Beaufrere, Anne-Marie; Pebrel-Richard, Céline; Thevenon, Julien; El Chehadeh-Djebbar, Salima; Faivre, Laurence; Duffourd, Yannis; Ricci, Federica; Mongini, Tiziana; Fiorillo, Chiara; Astrea, Guja; Burloiu, Carmen Magdalena; Butoianu, Niculina; Sandu, Carmen; Servais, Laurent; Bonne, Gisèle; Nelson, Isabelle; Desguerre, Isabelle; Nougues, Marie-Christine; Bœuf, Benoit; Romero, Norma; Laporte, Jocelyn; Boland, Anne; Lechner, Doris; Deleuze, Jean-François; Fontaine, Bertrand; Strochlic, Laure; Lochmuller, Hanns; Eymard, Bruno; Mayer, Michèle; Nicole, Sophie

    2016-09-01

    The neuromuscular junction (NMJ) is one of the best-studied cholinergic synapses. Inherited defects of peripheral neurotransmission result in congenital myasthenic syndromes (CMSs), a clinically and genetically heterogeneous group of rare diseases with fluctuating fatigable muscle weakness as the clinical hallmark. Whole-exome sequencing and Sanger sequencing in six unrelated families identified compound heterozygous and homozygous mutations in SLC5A7 encoding the presynaptic sodium-dependent high-affinity choline transporter 1 (CHT), which is known to be mutated in one dominant form of distal motor neuronopathy (DHMN7A). We identified 11 recessive mutations in SLC5A7 that were associated with a spectrum of severe muscle weakness ranging from a lethal antenatal form of arthrogryposis and severe hypotonia to a neonatal form of CMS with episodic apnea and a favorable prognosis when well managed at the clinical level. As expected given the critical role of CHT for multisystemic cholinergic neurotransmission, autonomic dysfunctions were reported in the antenatal form and cognitive impairment was noticed in half of the persons with the neonatal form. The missense mutations induced a near complete loss of function of CHT activity in cell models. At the human NMJ, a delay in synaptic maturation and an altered maintenance were observed in the antenatal and neonatal forms, respectively. Increased synaptic expression of butyrylcholinesterase was also observed, exposing the dysfunction of cholinergic metabolism when CHT is deficient in vivo. This work broadens the clinical spectrum of human diseases resulting from reduced CHT activity and highlights the complexity of cholinergic metabolism at the synapse. PMID:27569547

  3. Uptake of /sup 3/H-choline and synthesis of /sup 3/H-acetylcholine by human penile corpus cavernosum

    SciTech Connect

    Blanco, R.; Saenz de Tejada, I.; Azadzoi, K.; Goldstein, I.; Krane, R.J.; Wotiz, H.H.; Cohen, R.A.

    1986-03-05

    The neuroeffectors which relax penile smooth muscle and lead to erection are unknown; physiological studies of human corpus cavernosum, in vitro, have suggested a significant role of cholinergic neurotransmission. To further characterize the importance of cholinergic nerves, biopsies of human corpus cavernosum were obtained at the time of penile prosthesis implantation. Tissues were incubated in /sup 3/H-choline (10/sup -5/M, 80 Ci/mmol) in oxygenated physiological salt solution at 37/sup 0/C, pH 7.4 for 1 hour. Radiolabelled compounds were extracted with perchloric acid (0.4 M) and acetylcholine and choline were separated by HPLC; /sup 14/C-acetylcholine was used as internal standard. /sup 3/H-choline was accumulated by the tissues (20 +/- 1.9 fmol/mg), and /sup 3/H-acetylcholine was synthesized (4.0 +/- 1.1 fmol/mg). In control experiments, heating of the tissue blocked synthesis of /sup 3/H-acetylcholine. Inhibition of high affinity choline transport by hemicholinium-3 (10/sup -5/M) diminished tissue accumulation of /sup 3/H-choline and significantly reduced the synthesis of /sup 3/H-acetylcholine (0.5 +/ 0.2 fmol/mg, p < 0.05). These results provide direct evidence of neuronal accumulation of choline and enzymatic conversion to acetylcholine in human corpus cavernosum. Taken together with the physiological studies, it can be concluded that cholinergic neurotransmission in human corpus cavernosum plays a role in penile erection.

  4. Occurrence of Choline and Glycine Betaine Uptake and Metabolism in the Family Rhizobiaceae and Their Roles in Osmoprotection

    PubMed Central

    Boncompagni, Eric; Østerås, Magne; Poggi, Marie-Christine; le Rudulier, Daniel

    1999-01-01

    The role of glycine betaine and choline in osmoprotection of various Rhizobium, Sinorhizobium, Mesorhizobium, Agrobacterium, and Bradyrhizobium reference strains which display a large variation in salt tolerance was investigated. When externally provided, both compounds enhanced the growth of Rhizobium tropici, Sinorhizobium meliloti, Sinorhizobium fredii, Rhizobium galegae, Agrobacterium tumefaciens, Mesorhizobium loti, and Mesorhizobium huakuii, demonstrating their utilization as osmoprotectants. However, both compounds were inefficient for the most salt-sensitive strains, such as Rhizobium leguminosarum (all biovars), Agrobacterium rhizogenes, Rhizobium etli, and Bradyrhizobium japonicum. Except for B. japonicum, all strains exhibit transport activity for glycine betaine and choline. When the medium osmolarity was raised, choline uptake activity was inhibited, whereas glycine betaine uptake was either increased in R. leguminosarum and S. meliloti or, more surprisingly, reduced in R. tropici, S. fredii, and M. loti. The transport of glycine betaine was increased by growing the cells in the presence of the substrate. With the exception of B. japonicum, all strains were able to use glycine betaine and choline as sole carbon and nitrogen sources. This catabolic function, reported for only a few soil bacteria, could increase competitiveness of rhizobial species in the rhizosphere. Choline dehydrogenase and betaine-aldehyde dehydrogenase activities were present in the cells of all strains with the exception of M. huakuii and B. japonicum. The main physiological role of glycine betaine in the family Rhizobiaceae seems to be as an energy source, while its contribution to osmoprotection is restricted to certain strains. PMID:10224003

  5. Uptake and utilization of CDP-choline in primary brain cell cultures from fetal brain

    SciTech Connect

    Vecchini, A.; Binaglia, L.; Floridi, A.; Palmerini, C.A.; Procellati, G.

    1983-03-01

    The utilization of double-labeled CDP-choline by cultured brain cells has been studied. CDP-choline is demonstrated to be rapidly hydrolysed into CMP and choline phosphate. The fragments, or their hydrolysis products, penetrate into the cells and are utilized for lipid synthesis. At short times after the isotope administration a rapid labeling of phosphatidylcholine was detected, when cells were incubated with CDP-choline. The same was not seen when cells were incubated with labeled choline. From these observations it can be inferred that either CDP- choline can penetrate the cell membrane or that some mechanism involving CDP-choline and leading to phospholipid synthesis can work at the external surface of the plasma membranes.

  6. Automated evaluation of protein binding affinity of anti-inflammatory choline based ionic liquids.

    PubMed

    Ribeiro, Rosa; Pinto, Paula C A G; Azevedo, Ana M O; Bica, Katharina; Ressmann, Anna K; Reis, Salette; Saraiva, M Lúcia M F S

    2016-04-01

    In this work, an automated system for the study of the interaction of drugs with human serum albumin (HSA) was developed. The methodology was based on the quenching of the intrinsic fluorescence of HSA by binding of the drug to one of its binding sites. The fluorescence quenching assay was implemented in a sequential injection analysis (SIA) system and the optimized assay was applied to ionic liquids based on the association of non-steroidal anti-inflammatory drugs with choline (IL-API). In each cycle, 100 µL of HSA and 100 µL of IL-API (variable concentration) were aspirated at a flow rate of 1 mL min(-1) and then sent through the reaction coil to the detector where the fluorescence intensity was measured. In the optimized conditions the effect of increasing concentrations of choline ketoprofenate and choline naproxenate (and respective starting materials: ketoprofen and naproxen) on the intrinsic fluorescence of HSA was studied and the dissociation constants (Kd) were calculated by means of models of drug-protein binding in the equilibrium. The calculated Kd showed that all the compounds bind strongly to HSA (Kd<100 µmol L(-1)) and that the use of the drugs in the IL format does not affect or can even improve their HSA binding. The obtained results were compared with those provided by a conventional batch assay and the relative errors were lower than 4.5%. The developed SIA methodology showed to be robust and exhibited good repeatability in all the assay conditions (rsd<6.5%). PMID:26838377

  7. Human TMEM30a Promotes Uptake of Anti-tumor and Bioactive Choline Phospholipids into Mammalian Cells1

    PubMed Central

    Chen, Rui; Brady, Erin; McIntyre, Thomas M.

    2010-01-01

    Anti-tumor alkylphospholipids initiate apoptosis in transformed HL-60 and Jurkat cells while sparing their progenitors. Edelfosine like other short-chained phospholipids—inflammatory Platelet-activating Factor (PAF) and apoptotic oxidatively-truncated phospholipids—are proposed to have intracellular sites of action, yet a conduit for these choline phospholipids into mammalian cells is undefined. Edelfosine is also accumulated by Saccharomyces cerevisiae in process requiring the membrane protein Lem3p, and the human genome contains a Lem3p homolog TMEM30a. We show import of choline phospholipids into S. cerevisiae ⊗Lem3 is partially reconstituted by human TMEM30a and by Lem3p-TMEM30a chimeras, showing the proteins are orthologous. TMEM30a-GFP chimeras expressed in mammalian cells localized in plasma membranes, as well as internal organelles, and ectopic TMEM30a expression promoted uptake of exogenous choline and ethanolamine phospholipids. shRNA knockdown of TMEM30a reduced fluorescent choline phospholipid and [3H]PAF import. This knockdown also reduced mitochondrial depolarization from exogenous Edelfosine or the mitotoxic oxidatively truncated phospholipid azelaoyl phosphatidylcholine, and the knockdown reduced apoptosis in response to these two phospholipids. These results show extracellular choline phospholipids with short sn-2 residues can have intracellular roles and sites of metabolism because they are transport substrates for a TMEM30a phospholipid import system. Variation in this mechanism could limit sensitivity to short-chain choline phospholipids such as Edelfosine, PAF, and pro-apoptotic phospholipids. PMID:21289302

  8. High-affinity uptake of noradrenaline in postsynaptic neurones.

    PubMed Central

    al-Damluji, S.; Krsmanovic, L. Z.; Catt, K. J.

    1993-01-01

    1. Neurotransmitters released from nerve endings are inactivated by re-uptake into the presynaptic nerve terminals and possibly into neighbouring glial cells. While analysing the functional properties of alpha 1-adrenoceptors in the hypothalamus, we observed a high-affinity uptake process for noradrenaline in postsynaptic peptidergic neurones. 2. In primary hypothalamic cell cultures and in a hypothalamic neuronal cell line, [3H]-prazosin bound with high affinity and was displaced by unlabelled prazosin in concentrations of 10(-10) to 10(-7) M. However, at concentrations of unlabelled prazosin above 10(-7) M, there was a paradoxical increase in apparent [3H]-prazosin binding. 3. Methoxamine, an alpha 1-adrenoceptor ligand that is not subject to significant neuronal uptake, displaced [3H]-prazosin but did not cause the paradoxical increase in the apparent binding of [3H]-prazosin. Cooling the cells to 4 degrees C reduced the total amount of prazosin associated with the cells; under these conditions, methoxamine almost completely inhibited [3H]-prazosin binding to the cells. 4. In the presence of desipramine (DMI), unlabelled prazosin displaced [3H]-prazosin as before, but no paradoxical increase in apparent binding was seen above 10(-7) M. 5. The paradoxical increase of [3H]-prazosin binding was not observed in membrane preparations of hypothalamic neurones. These findings indicated that the paradoxical increase in apparent [3H]-prazosin binding was due to a cellular uptake process that becomes evident at high concentrations of the ligand. 6. DMI (10(-5) M) had no effect on the specific binding of [3H]-prazosin.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8358534

  9. Determinants of benzodiazepine brain uptake: lipophilicity versus binding affinity.

    PubMed

    Arendt, R M; Greenblatt, D J; Liebisch, D C; Luu, M D; Paul, S M

    1987-01-01

    Factors influencing brain uptake of benzodiazepine derivatives were evaluated in adult Sprague Dawley rats (n = 8-10 per drug). Animals received single intraperitoneal doses of alprazolam, triazolam, lorazepam, flunitrazepam, diazepam, midazolam, desmethyldiazepam, or clobazam. Concentrations of each drug (and metabolites) in whole brain and serum 1 h after dosage were determined by gas chromatography. Serum free fraction was measured by equilibrium dialysis. In vitro binding affinity (apparent Ki) of each compound was estimated based on displacement of tritiated flunitrazepam in washed membrane preparations from rat cerebral cortex. Lipid solubility of each benzodiazepine was estimated using the reverse-phase liquid chromatographic (HPLC) retention index at physiologic pH. There was no significant relation between brain:total serum concentration ratio and either HPLC retention (r = 0.18) or binding Ki (r = -0.34). Correction of uptake ratios for free as opposed to total serum concentration yielded a highly significant correlation with HPLC retention (r = 0.78, P less than 0.005). However, even the corrected ratio was not correlated with binding Ki (r = -0.22). Thus a benzodiazepine's capacity to diffuse from systemic blood into brain tissue is much more closely associated with the physicochemical property of lipid solubility than with specific affinity. Unbound rather than total serum or plasma concentration most accurately reflects the quantity of drug available for diffusion. PMID:2888155

  10. The sea urchin embryo as a model for mammalian developmental neurotoxicity: ontogenesis of the high-affinity choline transporter and its role in cholinergic trophic activity.

    PubMed Central

    Qiao, Dan; Nikitina, Lyudmila A; Buznikov, Gennady A; Lauder, Jean M; Seidler, Frederic J; Slotkin, Theodore A

    2003-01-01

    Embryonic development in the sea urchin requires trophic actions of the same neurotransmitters that participate in mammalian brain assembly. We evaluated the development of the high-affinity choline transporter, which controls acetylcholine synthesis. A variety of developmental neurotoxicants affect this transporter in mammalian brain. [3H]Hemicholinium-3 binding to the transporter was found in the cell membrane fraction at stages from the unfertilized egg to pluteus, with a binding affinity comparable with that seen in mammalian brain. Over the course of development, the concentration of transporter sites rose more than 3-fold, achieving concentrations comparable with those of cholinergically enriched mammalian brain regions. Dimethylaminoethanol (DMAE), a competitive inhibitor of choline transport, elicited dysmorphology beginning at the mid-blastula stage, with anomalies beginning progressively later as the concentration of DMAE was lowered. Pretreatment, cotreatment, or delayed treatment with acetylcholine or choline prevented the adverse effects of DMAE. Because acetylcholine was protective at a lower threshold, the DMAE-induced defects were most likely mediated by its effects on acetylcholine synthesis. Transient removal of the hyaline layer enabled a charged transport inhibitor, hemicholinium-3, to penetrate sufficiently to elicit similar anomalies, which were again prevented by acetylcholine or choline. These results indicate that the developing sea urchin possesses a high-affinity choline transporter analogous to that found in the mammalian brain, and, as in mammals, the functioning of this transporter plays a key role in the developmental, trophic activity of acetylcholine. The sea urchin model may thus be useful in high-throughput screening of suspected developmental neurotoxicants. PMID:14594623

  11. AGE-RELATED EFFECTS OF CHLORPYRIFOS ON HIGH AFFINITY CHOLINE UPTAKE IN RAT BRAIN. (R825811)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  12. Low and high affinity dopamine transporter inhibitors block dopamine uptake within 5 sec of intravenous injection

    PubMed Central

    Yorgason, Jordan T.; Jones, Sara R.; España, Rodrigo A.

    2011-01-01

    Extensive evidence suggests that the reinforcing effects of cocaine involve inhibition of dopamine transporters (DAT) and subsequent increases in dopamine (DA) levels in the striatum. We have previously reported that cocaine inhibits the DAT within 4–5 sec of intravenous injection, matching the temporal profile of the behavioral and subjective effects of cocaine. Intravenous injection of GBR-12909, a high affinity, long-acting DAT inhibitor, also inhibits DA uptake within 5 sec. Given that high affinity, long-acting drugs are considered to have relatively low abuse potential, we found it intriguing that GBR-12909 had an onset profile similar to that of cocaine. To further explore the onset kinetics of both low and high affinity DAT inhibitors, we examined the effects of intravenous cocaine (1.5 mg/kg), methylphenidate (1.5 mg/kg), nomifensine (1.5 mg/kg), GBR-12909 (1.5 mg/kg), PTT (0.5 mg/kg), and WF23 (0.5 mg/kg) on electrically-evoked DA release and uptake in the nucleus accumbens core. Results indicate that all of the DAT inhibitors significantly inhibited DA uptake within 5 sec of injection. However, the timing of peak uptake inhibition varied greatly between the low and high affinity uptake inhibitors. Uptake inhibition following cocaine, methylphenidate, and nomifensine peaked 30 sec following injection. In contrast, peak effects for GBR-12909, PTT, and WF23 occurred between 20 and 60 min following injection. These observations suggest that the initial onset for intravenous DAT inhibitors is extremely rapid and does not appear to be dictated by a drug’s affinity. PMID:21402130

  13. Characterization of the Rhizobium (Sinorhizobium) meliloti high- and low-affinity phosphate uptake systems.

    PubMed Central

    Voegele, R T; Bardin, S; Finan, T M

    1997-01-01

    Genetic studies have suggested that Rhizobium (Sinorhizobium) meliloti contains two distinct phosphate (Pi) transport systems, encoded by the phoCDET genes and the orfA-pit genes, respectively. Here we present data which show that the ABC-type PhoCDET system has a high affinity for Pi (Km, 0.2 microM) and that Pi uptake by this system is severely inhibited by phosphonates. This high-affinity uptake system was induced under Pi-limiting conditions and was repressed in the presence of excess Pi. Uptake via the OrfA-Pit system was examined in (i) a phoC mutant which showed increased expression of the orfA-pit genes as a result of a promoter-up mutation and (ii) a phoB mutant (PhoB is required for phoCDET expression). Pi uptake in both strains exhibited saturation kinetics (Km, 1 to 2 microM) and was not inhibited by phosphonates. This uptake system was active in wild-type cells grown with excess Pi and appeared to be repressed when the cells were starved for Pi. Thus, our biochemical data show that the OrfA-Pit and PhoCDET uptake systems are differentially expressed depending on the state of the cell with respect to phosphate availability. PMID:9393684

  14. A molecular recognizing system of serotonin in rat fetal axonal growth cones: uptake and high affinity binding.

    PubMed

    Mercado, R; Hernández, J

    1992-09-18

    Axonal growth cone particles (AGCP) isolated from prenatal and postnatal rat brain had different high-affinity 5-HT uptake characteristics. In postnatal AGCP the uptake behaves as in the adult rat brain, while in the prenatal AGCP the uptake characteristics seem to be in a transitional stage. Also in prenatal AGCP we observed specific, high-affinity 5-HT binding sites. These results support the idea of an important role for 5-HT during axogenesis. PMID:1424085

  15. Development of a high-affinity GABA uptake system in embryonic amphibian spinal neurons.

    PubMed

    Lamborghini, J E; Iles, A

    1985-11-01

    High-affinity uptake systems for amino acid neurotransmitter precursors have been highly correlated with the use of the particular amino acid or its derivative as a transmitter. We have found interneurons in the Xenopus embryo spinal cord which accumulate GABA by a high-affinity uptake system. They originate near the end of gastrulation and their ability to accumulate GABA first appears at the early tail bud stage. By position and appearance they are comparable to some of the embryonic interneurons described by A. Roberts and J. D. W. Clarke (1982, Phil. Trans. R. Soc. London Ser. B 296, 195-212). GABA-accumulating neurons also develop in dissociated cell cultures made from the presumptive spinal cord of neural plate stage Xenopus embryos. GABA accumulation in cultured neurons, as in cells in vivo, occurs via a high-affinity uptake system; GABA-accumulating cells have the same time of origin as the cells in vivo, and the ability to accumulate GABA in the population of cultured neurons appears at a time equivalent to that observed in intact sibling embryos. Thus it seems likely that the population of GABA-accumulating neurons developing in cell culture corresponds to the GABA-accumulating interneurons in vivo. The development of these neurons in dissociated cell cultures permits perturbation experiments that would be difficult to perform in vivo. We have examined the development of high-affinity GABA uptake in conditions that permit no electrical impulse activity in the cultures. The onset and extent of development of GABA accumulation in the neuronal population are normal under these conditions. PMID:3932109

  16. Analysis of the high-affinity iron uptake system at the Chlamydomonas reinhardtii plasma membrane.

    PubMed

    Terzulli, Alaina; Kosman, Daniel J

    2010-05-01

    Multicopper ferroxidases play a vital role in iron metabolism in bacteria, fungi, algae, and mammals. Saccharomyces cerevisiae utilizes a channeling mechanism to couple the ferroxidase activity of Fet3p to Fe(3+) transport into the cell by Ftr1p. In contrast, the mechanisms by which mammals couple the ferroxidase reaction to iron trafficking is unclear. The human ferroxidases ceruloplasmin and hephaestin are twice the size of Fet3p and interact with proteins that are not expressed in fungi. Chlamydomonas FOX1 is a homolog of the human ferroxidases but likely supports iron uptake in a manner similar to that of yeast, since Chlamydomonas reinhardtii expresses a ferric iron permease homolog, FTR1. The results presented support this hypothesis. We show that FOX1 is trafficked to the plasma membrane and is oriented with its multicopper oxidase/ferroxidase domain in the exocytoplasmic space. Our analysis of FTR1 indicates its topology is similar to that of S. cerevisiae Ftr1p, with a potential exocytoplasmic iron channeling motif and two potential iron permeation motifs in membrane-spanning regions. We demonstrate that high-affinity iron uptake is dependent on FOX1 and the copper status of the cell. Kinetic inhibition of high-affinity iron uptake by a ferric iron chelator does not reflect the strength of the chelator, supporting a ferric iron channeling mechanism for high-affinity iron uptake in Chlamydomonas. Last, recombinant FOX1 (rFOX1) has been isolated in a partially holo form that exhibits the UV-visible absorbance spectrum of a multicopper oxidase and the catalytic activity of a ferroxidase. PMID:20348389

  17. High and Low Affinity Urea Root Uptake: Involvement of NIP5;1.

    PubMed

    Yang, Huayiu; Menz, Jochen; Häussermann, Iris; Benz, Martin; Fujiwara, Toru; Ludewig, Uwe

    2015-08-01

    Urea is the most widespread nitrogen (N) fertilizer worldwide and is rapidly degraded in soil to ammonium by urease. Ammonium is either taken up by plant roots or is further processed to nitrate by soil microorganisms. However, urea can be taken up by roots and is further degraded to ammonium by plant urease for assimilation. When urea is supplied under sterile conditions, it acts as a poor N source for seedlings or adult Arabidopsis thaliana plants. Here, the gene expression of young seedlings exposed to urea and ammonium nitrate nutrition was compared. Several primary metabolism and transport genes, including those for nitrate and urea, were differentially expressed in seedlings. However, urease and most major intrinsic proteins were not differentially expressed, with the exception of NIP6;1, a urea-permeable channel, which was repressed. Furthermore, little overlap with the gene expression with ammonium as the sole N source was observed, confirming that pure urea nutrition is not associated with the ammonium toxicity syndrome in seedlings. The direct root uptake of urea was increased under boron deficiency, in both the high and low affinity range. This activity was entirely mediated by the NIP5;1 channel, which was confirmed to transport urea when expressed in oocytes. The uptake of urea in the high and low affinity range was also determined for maize and wheat roots. The urea uptake by maize roots was only about half that of wheat, but was not stimulated by boron deficiency or N deficiency in either species. This analysis identifies novel components of the urea uptake systems in plants, which may become agronomically relevant to urea uptake and utilization, as stabilized urea fertilizers become increasingly popular. PMID:25957355

  18. An Arabidopsis thaliana high-affinity molybdate transporter required for efficient uptake of molybdate from soil

    PubMed Central

    Tomatsu, Hajime; Takano, Junpei; Takahashi, Hideki; Watanabe-Takahashi, Akiko; Shibagaki, Nakako; Fujiwara, Toru

    2007-01-01

    Molybdenum (Mo) is a trace element essential for living organisms, however no molybdate transporter has been identified in eukaryotes. Here, we report the identification of a molybdate transporter, MOT1, from Arabidopsis thaliana. MOT1 is expressed in both roots and shoots, and the MOT1 protein is localized, in part, to plasma membranes and to vesicles. MOT1 is required for efficient uptake and translocation of molybdate and for normal growth under conditions of limited molybdate supply. Kinetics studies in yeast revealed that the Km value of MOT1 for molybdate is ≈20 nM. Furthermore, Mo uptake by MOT1 in yeast was not affected by coexistent sulfate, and MOT1 did not complement a sulfate transporter-deficient yeast mutant strain. These data confirmed that MOT1 is specific for molybdate and that the high affinity of MOT1 allows plants to obtain scarce Mo from soil. PMID:18003916

  19. The Long and Winding Road: from the high affinity choline uptake site to clinical trials for malignant brain tumors

    PubMed Central

    Lowenstein, Pedro R.; Castro, Maria G.

    2016-01-01

    Malignant brain tumors are one of the most lethal cancers. They originate from glial cells and invade throughout the brain. Current standard of care involves surgical resection, radiotherapy and chemotherapy, and median survival is currently ~14–20 months post-diagnosis. Glioma tumors are highly infiltrative. Given that the brain immune system is deficient in priming systemic immune responses to glioma antigens present within the brain, we proposed to reconstitute the brain immune system to achieve immunological priming from within the brain. Two adenoviral vectors are injected into the resection cavity or remaining tumor. One adenoviral vector expresses the HSV-1 derived thymidine kinase which converts ganciclovir into a compound only cytotoxic to dividing glioma cells. The second adenovirus expresses the cytokine fms-like tyrosine kinase 3 ligand (Flt3L). Flt3L differentiates precursors into dendritic cells and acts as a chemokine for dendritic cells. HSV-1/ganciclovir killing of tumor cells releases tumor antigens that are taken up by dendritic cells within the brain tumor microenvironment. Tumor killing also releases HMGB1, a TLR2 agonist that activates dendritic cells. HMGB1 activated dendritic cells, loaded with glioma antigens, migrate to cervical lymph nodes to stimulate a systemic CD8+ T cells cytotoxic immune response against glioma. This immune response is specific to glioma tumors, induces immunological memory, and does neither cause brain toxicity nor autoimmune responses. An IND was granted by the FDA on 4/7/2011. A Phase I, first in person, to test whether re-engineering the brain immune system is potentially therapeutic is ongoing. PMID:27288077

  20. The Long and Winding Road: From the High-Affinity Choline Uptake Site to Clinical Trials for Malignant Brain Tumors.

    PubMed

    Lowenstein, P R; Castro, M G

    2016-01-01

    Malignant brain tumors are one of the most lethal cancers. They originate from glial cells which infiltrate throughout the brain. Current standard of care involves surgical resection, radiotherapy, and chemotherapy; median survival is currently ~14-20 months postdiagnosis. Given that the brain immune system is deficient in priming systemic immune responses to glioma antigens, we proposed to reconstitute the brain immune system to achieve immunological priming from within the brain. Two adenoviral vectors are injected into the resection cavity or remaining tumor. One adenoviral vector expresses the HSV-1-derived thymidine kinase which converts ganciclovir into a compound only cytotoxic to dividing glioma cells. The second adenovirus expresses the cytokine fms-like tyrosine kinase 3 ligand (Flt3L). Flt3L differentiates precursors into dendritic cells and acts as a chemokine that attracts dendritic cells to the brain. HSV-1/ganciclovir killing of tumor cells releases tumor antigens that are taken up by dendritic cells within the brain tumor microenvironment. Tumor killing also releases HMGB1, an endogenous TLR2 agonist that activates dendritic cells. HMGB1-activated dendritic cells, loaded with glioma antigens, migrate to cervical lymph nodes to stimulate a systemic CD8+ T cells cytotoxic immune response against glioma. This immune response is specific to glioma tumors, induces immunological memory, and does neither cause brain toxicity nor autoimmune responses. An IND was granted by the FDA on 4/7/2011. A Phase I, first in person trial, to test whether reengineering the brain immune system is potentially therapeutic is ongoing. PMID:27288077

  1. IN VITRO EFFECTS OF ORGANOPHOSPHORUS ANTICHOLINESTERASES AND MUSCARINIC AGONISTS ON RAT BRAIN SYNAPTOSOMAL HIGH AFFINITY CHOLINE UPTAKE. (R825811)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  2. Cloning and functional characterization of an Arabidopsis nitrate transporter gene that encodes a constitutive component of low-affinity uptake.

    PubMed Central

    Huang, N C; Liu, K H; Lo, H J; Tsay, Y F

    1999-01-01

    The Arabidopsis CHL1 (AtNRT1) gene encodes an inducible component of low-affinity nitrate uptake, which necessitates a "two-component" model to account for the constitutive low-affinity uptake observed in physiological studies. Here, we report the cloning and characterization of a CHL1 homolog, AtNRT1:2 (originally named NTL1), with data to indicate that this gene encodes a constitutive component of low-affinity nitrate uptake. Transgenic plants expressing antisense AtNRT1:2 exhibited reduced nitrate-induced membrane depolarization and nitrate uptake activities in assays with 10 mM nitrate. Furthermore, transgenic plants expressing antisense AtNRT1:2 in the chl1-5 background exhibited an enhanced resistance to chlorate (7 mM as opposed to 2 mM for the chl1-5 mutant). Kinetic analysis of AtNRT1:2-injected Xenopus oocytes yielded a K(m) for nitrate of approximately 5.9 mM. In contrast to CHL1, AtNRT1:2 was constitutively expressed before and after nitrate exposure (it was repressed transiently only when the level of CHL1 mRNA started to increase significantly), and its mRNA was found primarily in root hairs and the epidermis in both young (root tips) and mature regions of roots. We conclude that low-affinity systems of nitrate uptake, like high-affinity systems, are composed of inducible and constitutive components and that with their distinct functions, they are part of an elaborate nitrate uptake network in Arabidopsis. PMID:10449574

  3. The antihyperalgesic effect of cytidine-5'-diphosphate-choline in neuropathic and inflammatory pain models.

    PubMed

    Bagdas, Deniz; Sonat, Fusun Ak; Hamurtekin, Emre; Sonal, Songul; Gurun, Mine Sibel

    2011-09-01

    This study was designed to test the effects of intracerebroventricularly (i.c.v.) administered CDP-choline (cytidine-5'-diphosphate-choline; citicoline) and its metabolites in rat models of inflammatory and neuropathic pain. The i.c.v. administration of CDP-choline (0.5, 1.0 and 2.0 µmol) produced a dose and time-dependent reversal of mechanical hyperalgesia in both carrageenan-induced inflammatory and chronic constriction injury-induced neuropathic pain models in rats. The antihyperalgesic effect of CDP-choline was similar to that observed with an equimolar dose of choline (1 µmol). The CDP-choline-induced antihyperalgesic effect was prevented by central administration of the neuronal high-affinity choline uptake inhibitor hemicholinium-3 (1 µg), the nonselective nicotinic receptor antagonist mecamylamine (50 µg), the α7-selective nicotinic ACh receptor antagonist, α-bungarotoxin (2 µg) and the γ-aminobutyric acid B receptor antagonist CGP-35348 (20 µg). In contrast, i.c.v. pretreatment with the nonselective opioid receptor antagonist naloxone (10 µg) only prevented the CDP-choline-induced antihyperalgesic effect in the neuropathic pain model while the nonselective muscarinic receptor antagonist atropine (10 µg) did not alter the antihyperalgesic effect in the two models. These results indicate that CDP-choline-elicited antihyperalgesic effect in different models of pain occurs through mechanisms that seem to involve an interaction with supraspinal α7-selective nicotinic ACh receptors, and γ-aminobutyric acid B receptors, whereas central opioid receptors have a role only in the neuropathic pain model. PMID:21836465

  4. Blood-brain barrier transport of choline is reduced in the aged rat.

    PubMed

    Mooradian, A D

    1988-02-01

    An age-related impairment in choline transport across the blood-brain barrier (BBB) may contribute to the cholinergic mechanisms of geriatric memory dysfunction. To test this hypothesis, the brain choline uptake in male Fisher 344 rats at 2, 18 and 24 months of age was studied using the Oldendorf technique. The Vmax of choline transport in the 24-month-old rats (0.05 +/- 0.04 nmol/min/g) was significantly lower than that in the 2-month-old rat (2.5 +/- 1.0 nmol/min/g) (P less than 0.05). The Km of transport in old rats (13 +/- 35 microM) was also significantly smaller than the value in 24-month-old rats (450 +/- 195 microM), while the constant of the non-saturable component of the transport, Kd, was not significantly different in older rats (1.2 +/- 0.3 vs 0.6 +/- 0.1 microliter/min/g). These results indicate that the carrier in old rats has reduced capacity and increased affinity to choline. The reduced choline carrier capacity explains the significant decrease in BBB choline transport in aged rats. PMID:3359216

  5. Temperature dependence of inorganic nitrogen uptake: Reduced affinity for nitrate at suboptimal temperatures in both algae and bacteria

    SciTech Connect

    Reay, D.S.; Nedwell, D.B.; Priddle, J.; Ellis-Evans, J.C.

    1999-06-01

    Nitrate utilization and ammonium utilization were studied by using three algal isolates, six bacterial isolates, and a range of temperatures in chemostat and batch cultures. The authors quantified affinities for both substrates by determining specific affinities based on estimates of kinetic parameters obtained from chemostat experiments. At suboptimal temperatures, the residual concentrations of nitrate in batch cultures and the steady-state concentrations of nitrate in chemostat cultures both increased. The specific affinity for nitrate was strongly dependent on temperature and consistently decreased at temperatures below the optimum temperature. In contrast, the steady-state concentrations of ammonium remained relatively constant over the same temperature range, and the specific affinity for ammonium exhibited no clear temperature dependence. This is the first time that a consistent effect of low temperature on affinity for nitrate has been identified for psychrophilic, mesophilic, and thermophilic bacteria and algae. The different responses of nitrate uptake and ammonium uptake to temperature imply that there is increasing dependence on ammonium as an inorganic nitrogen source at low temperatures.

  6. Characterization of AMT-mediated high-affinity ammonium uptake in roots of maize (Zea mays L.).

    PubMed

    Gu, Riliang; Duan, Fengying; An, Xia; Zhang, Fusuo; von Wirén, Nicolaus; Yuan, Lixing

    2013-09-01

    High-affinity ammonium uptake in plant roots is mainly mediated by AMT1-type ammonium transporters, and their regulation varies depending on the plant species. In this study we aimed at characterizing AMT-mediated ammonium transport in maize, for which ammonium-based fertilizer is an important nitrogen (N) source. Two ammonium transporter genes, ZmAMT1;1a and ZmAMT1;3, were isolated from a maize root-specific cDNA library by functional complementation of an ammonium uptake-defective yeast mutant. Ectopic expression of both genes in an ammonium uptake-defective Arabidopsis mutant conferred high-affinity ammonium uptake capacities in roots with substrate affinities of 48 and 33 μM for ZmAMT1;1a and ZmAMT1;3, respectively. In situ hybridization revealed co-localization of both ZmAMT genes on the rhizodermis, suggesting an involvement in capturing ammonium from the rhizosphere. In N-deficient maize roots, influx increased significantly while ZmAMT expression did not. Ammonium resupply to N-deficient or nitrate-pre-cultured roots, however, rapidly enhanced both influx and ZmAMT transcript levels, revealing a substrate-inducible regulation of ammonium uptake. In conclusion, the two rhizodermis-localized transporters ZmAMT1;1a and ZmAMT1;3 are most probably the major components in the high-affinity transport system in maize roots. A particular regulatory feature is their persistent induction by ammonium rather than an up-regulation under N deficiency. PMID:23832511

  7. A two-component high-affinity nitrate uptake system in barley.

    PubMed

    Tong, Yiping; Zhou, Jing-Jiang; Li, Zhensheng; Miller, Anthony J

    2005-02-01

    The analysis of genome databases for many different plants has identified a group of genes that are related to one part of a two-component nitrate transport system found in algae. Earlier work using mutants and heterologous expression has shown that a high-affinity nitrate transport system from the unicellular green algae, Chlamydomonas reinhardtii required two gene products for function. One gene encoded a typical carrier-type structure with 12 putative trans-membrane (TM) domains and the other gene, nar2 encoded a much smaller protein that had only one TM domain. As both gene families occur in plants we investigated whether this transport model has more general relevance among plants. The screening for nitrate transporter activity was greatly helped by a novel assay using (15)N-enriched nitrate uptake into Xenopus oocytes expressing the proteins. This assay enables many oocytes to be rapidly screened for nitrate transport activity. The functional activity of a barley nitrate transporter, HvNRT2.1, in oocytes required co-injection of a second mRNA. Although three very closely related nar2-like genes were cloned from barley, only one of these was able to give functional nitrate transport when co-injected into oocytes. The nitrate transport performed by this two-gene system was inhibited at more acidic external pH and by acidification of the cytoplasm. This specific requirement for two-gene products to give nitrate transport function has important implications for attempts to genetically manipulate this fundamental process in plants. PMID:15659102

  8. Choline on the Move: Perspectives on the Molecular Physiology and Pharmacology of the Presynaptic Choline Transporter.

    PubMed

    Ennis, E A; Blakely, R D

    2016-01-01

    Genetic, biochemical, physiological, and pharmacological approaches have advanced our understanding of cholinergic biology for over 100 years. High-affinity choline uptake (HACU) was one of the last features of cholinergic signaling to be defined at a molecular level, achieved through the cloning of the choline transporter (CHT, SLC5A7). In retrospect, the molecular era of CHT studies initiated with the identification of hemicholinium-3 (HC-3), a potent, competitive CHT antagonist, though it would take another 30 years before HC-3, in radiolabeled form, was used by Joseph Coyle's laboratory to identify and monitor the dynamics of CHT proteins. Though HC-3 studies provided important insights into CHT distribution and regulation, another 15 years would pass before the structure of CHT genes and proteins were identified, a full decade after the cloning of most other neurotransmitter-associated transporters. The availability of CHT gene and protein probes propelled the development of cell and animal models as well as efforts to gain insights into how human CHT gene variation affects the risk for brain and neuromuscular disorders. Most recently, our group has pursued a broadening of CHT pharmacology, elucidating novel chemical structures that may serve to advance cholinergic diagnostics and medication development. Here we provide a short review of the transformation that has occurred in HACU research and how such advances may promote the development of novel therapeutics. PMID:27288078

  9. Dual Regulation of the Arabidopsis High-Affinity Root Iron Uptake System by Local and Long-Distance Signals1

    PubMed Central

    Vert, Grégory A.; Briat, Jean-François; Curie, Catherine

    2003-01-01

    Regulation of the root high-affinity iron uptake system by whole-plant signals was investigated at the molecular level in Arabidopsis, through monitoring FRO2 and IRT1 gene expression. These two genes encode the root ferric-chelate reductase and the high-affinity iron transporter, respectively, involved in the iron deficiency-induced uptake system. Recovery from iron-deficient conditions and modulation of apoplastic iron pools indicate that iron itself plays a major role in the regulation of root iron deficiency responses at the mRNA and protein levels. Split-root experiments show that the expression of IRT1 and FRO2 is controlled both by a local induction from the root iron pool and through a systemic pathway involving a shoot-borne signal, both signals being integrated to tightly control production of the root iron uptake proteins. We also show that IRT1 and FRO2 are expressed during the day and down-regulated at night and that this additional control is overruled by iron starvation, indicating that the nutritional status prevails on the diurnal regulation. Our work suggests, for the first time to our knowledge, that like in grasses, the root iron acquisition in strategy I plants may also be under diurnal regulation. On the basis of the new molecular insights provided in this study and given the strict coregulation of IRT1 and FRO2 observed, we present a model of local and long-distance regulation of the root iron uptake system in Arabidopsis. PMID:12805609

  10. Dual regulation of the Arabidopsis high-affinity root iron uptake system by local and long-distance signals.

    PubMed

    Vert, Grégory A; Briat, Jean-François; Curie, Catherine

    2003-06-01

    Regulation of the root high-affinity iron uptake system by whole-plant signals was investigated at the molecular level in Arabidopsis, through monitoring FRO2 and IRT1 gene expression. These two genes encode the root ferric-chelate reductase and the high-affinity iron transporter, respectively, involved in the iron deficiency-induced uptake system. Recovery from iron-deficient conditions and modulation of apoplastic iron pools indicate that iron itself plays a major role in the regulation of root iron deficiency responses at the mRNA and protein levels. Split-root experiments show that the expression of IRT1 and FRO2 is controlled both by a local induction from the root iron pool and through a systemic pathway involving a shoot-borne signal, both signals being integrated to tightly control production of the root iron uptake proteins. We also show that IRT1 and FRO2 are expressed during the day and down-regulated at night and that this additional control is overruled by iron starvation, indicating that the nutritional status prevails on the diurnal regulation. Our work suggests, for the first time to our knowledge, that like in grasses, the root iron acquisition in strategy I plants may also be under diurnal regulation. On the basis of the new molecular insights provided in this study and given the strict coregulation of IRT1 and FRO2 observed, we present a model of local and long-distance regulation of the root iron uptake system in Arabidopsis. PMID:12805609

  11. [Folate metabolism--epigenetic role of choline and vitamin B12 during pregnancy].

    PubMed

    Drews, Krzysztof

    2015-12-01

    Adequate choline intake during pregnancy is essential for proper fetal development. Nowadays studies suggest that even in high income countries regular pregnant women diet does not provide the satisfactory amount of choline. Choline demand during pregnancy is high and it seems to exceed present choline intake recommendations. Moreover lactation period also demands choline supplementation because of its high concentration in female milk. Numerous studies on animal model proved correlation between choline supplementation during pregnancy and proper fetal cognitive function development. Despite increased synthesis in maternal liver during pregnancy choline demand is much higher than common dietary uptake. Nowadays studies as to the nutritional recommendations during pregnancy concern also vitamin B12 supplementation. Vitamin B12 deficiency may be an important risk factor of neural tube defects development. Presented article contains a review of data on proper choline and vitamin B12 uptake during pregnancy and lactation and potential results of choline and vitamin B12 poor maternal status. PMID:26995945

  12. Choline Magnesium Trisalicylate

    MedlinePlus

    Choline magnesium trisalicylate is used to relieve the pain, tenderness, inflammation (swelling), and stiffness caused by arthritis and painful ... used to relieve pain and lower fever. Choline magnesium trisalicylate is in a class of nonsteroidal anti- ...

  13. Slight temperature changes affect protein affinity and cellular uptake/toxicity of nanoparticles

    NASA Astrophysics Data System (ADS)

    Mahmoudi, Morteza; Shokrgozar, Mohammad A.; Behzadi, Shahed

    2013-03-01

    It is known that what the cell actually ``sees'' at the nanoscale is an outer shell formed of `protein corona' on the surface of nanoparticles (NPs). The amount and composition of various proteins on the corona are strongly dependent on the biophysicochemical properties of NPs, which have been extensively studied. However, the effect of a small variation in temperature, due to the human circadian rhythm, on the composition of the protein corona and the affinity of various proteins to the surface of NPs, was ignored. Here, the effect of temperature on the composition of protein corona and the affinity of various proteins to the surface of NPs and, subsequently, cell responses to the protein coated NPs are probed. The results confirmed that cellular entrance, dispersion, and toxicity of NPs are strongly diverse with slight body temperature changes. This new finding can help scientists to maximise NP entrance to specific cells/organs with lower toxicity by adjusting the cellular/organ temperature.It is known that what the cell actually ``sees'' at the nanoscale is an outer shell formed of `protein corona' on the surface of nanoparticles (NPs). The amount and composition of various proteins on the corona are strongly dependent on the biophysicochemical properties of NPs, which have been extensively studied. However, the effect of a small variation in temperature, due to the human circadian rhythm, on the composition of the protein corona and the affinity of various proteins to the surface of NPs, was ignored. Here, the effect of temperature on the composition of protein corona and the affinity of various proteins to the surface of NPs and, subsequently, cell responses to the protein coated NPs are probed. The results confirmed that cellular entrance, dispersion, and toxicity of NPs are strongly diverse with slight body temperature changes. This new finding can help scientists to maximise NP entrance to specific cells/organs with lower toxicity by adjusting the cellular

  14. High-affinity manganese uptake by the metal transporter NRAMP1 is essential for Arabidopsis growth in low manganese conditions.

    PubMed

    Cailliatte, Rémy; Schikora, Adam; Briat, Jean-François; Mari, Stéphane; Curie, Catherine

    2010-03-01

    In contrast with many other essential metals, the mechanisms of Mn acquisition in higher eukaryotes are seldom studied and poorly understood. We show here that Arabidopsis thaliana relies on a high-affinity uptake system to acquire Mn from the soil in conditions of low Mn availability and that this activity is catalyzed by the divalent metal transporter NRAMP1 (for Natural Resistance Associated Macrophage Protein 1). The nramp1-1 loss-of-function mutant grows poorly, contains less Mn than the wild type, and fails to take up Mn in conditions of Mn limitation, thus demonstrating that NRAMP1 is the major high-affinity Mn transporter in Arabidopsis. Based on confocal microscopy observation of an NRAMP1-green fluorescent protein fusion, we established that NRAMP1 is localized to the plasma membrane. Consistent with its function in Mn acquisition from the soil, NRAMP1 expression is restricted to the root and stimulated by Mn deficiency. Finally, we show that NRAMP1 restores the capacity of the iron-regulated transporter1 mutant to take up iron and cobalt, indicating that NRAMP1 has a broad selectivity in vivo. The role of transporters of the NRAMP family is well established in higher eukaryotes for iron but has been controversial for Mn. This study demonstrates that NRAMP1 is a physiological manganese transporter in Arabidopsis. PMID:20228245

  15. Influence of temperature on growth rate and competition between two psychrotolerant Antarctic bacteria: low temperature diminishes affinity for substrate uptake.

    PubMed Central

    Nedwell, D B; Rutter, M

    1994-01-01

    The growth kinetics of two psychrotolerant Antarctic bacteria, Hydrogenophaga pseudoflava CR3/2/10 (2/10) and Brevibacterium sp. strain CR3/1/15 (1/15), were examined over a range of temperatures in both batch culture and glycerol-limited chemostat cultures. The maximum specific growth rate (mu max) and Ks values for both bacteria were functions of temperature, although the cell yields were relatively constant with respect to temperature. The mu max values of both strains increased up to an optimum temperature, 24 degrees C for 2/10 and 20 degrees C for 1/15. Strain 1/15 might therefore be considered to be more psychrophilic than strain 2/10. For both bacteria, the specific affinity (mu max/Ks) for glycerol uptake was lower at 2 than at 16 degrees C, indicating a greater tendency to substrate limitation at low temperature. As the temperature increased from 2 to 16 degrees C, the specific affinity of 1/15 for glycerol increased more rapidly than it did for 2/10. Thus 1/15, on the basis of this criterion, was less psychrophilic than was 2/10. The steady-state growth kinetics of the two strains at 2 and 16 degrees C imply that 1/15 would be able to outgrow 2/10 only at relatively low substrate concentrations (< 0.32 g of glycerol.liter-1) and high temperatures (> 12 degrees C), which suggests that 1/15 has a less psychrotolerant survival strategy than does 2/10. Our data were compared with other data in the literature for bacteria growing at low temperatures. They also showed an increase of substrate-specific affinity with increasing temperature.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8031092

  16. Fiber optic choline biosensor

    NASA Astrophysics Data System (ADS)

    Wang, Hong; Cao, Xiaojian; Jia, Ke; Chai, Xueting; Lu, Hua; Lu, Zuhong

    2001-10-01

    A fiber optic fluorescence biosensor for choline is introduced in this paper. Choline is an important neurotransmitter in mammals. Due to the growing needs for on-site clinical monitoring of the choline, much effect has been devoted to develop choline biosensors. Fiber-optic fluorescence biosensors have many advantages, including miniaturization, flexibility, and lack of electrical contact and interference. The choline fiber-optic biosensor we designed implemented a bifurcated fiber to perform fluorescence measurements. The light of the blue LED is coupled into one end of the fiber as excitation and the emission spectrum from sensing film is monitored by fiber-spectrometer (S2000, Ocean Optics) through the other end of the fiber. The sensing end of the fiber is coated with Nafion film dispersed with choline oxidase and oxygen sensitive luminescent Ru(II) complex (Tris(2,2'-bipyridyl)dichlororuthenium(II), hexahydrate). Choline oxidase catalyzes the oxidation of choline to betaine and hydrogen peroxide while consuming oxygen. The fluorescence intensity of oxygen- sensitive Ru(II) are related to the choline concentration. The response of the fiber-optic sensor in choline solution is represented and discussed. The result indicates a low-cost, high-performance, portable choline biosensor.

  17. Identification and Characterization of ML352: A Novel, Noncompetitive Inhibitor of the Presynaptic Choline Transporter

    PubMed Central

    2015-01-01

    The high-affinity choline transporter (CHT) is the rate-limiting determinant of acetylcholine (ACh) synthesis, yet the transporter remains a largely undeveloped target for the detection and manipulation of synaptic cholinergic signaling. To expand CHT pharmacology, we pursued a high-throughput screen for novel CHT-targeted small molecules based on the electrogenic properties of transporter-mediated choline transport. In this effort, we identified five novel, structural classes of CHT-specific inhibitors. Chemical diversification and functional analysis of one of these classes identified ML352 as a high-affinity (Ki = 92 nM) and selective CHT inhibitor. At concentrations that fully antagonized CHT in transfected cells and nerve terminal preparations, ML352 exhibited no inhibition of acetylcholinesterase (AChE) or cholineacetyltransferase (ChAT) and also lacked activity at dopamine, serotonin, and norepinephrine transporters, as well as many receptors and ion channels. ML352 exhibited noncompetitive choline uptake inhibition in intact cells and synaptosomes and reduced the apparent density of hemicholinium-3 (HC-3) binding sites in membrane assays, suggesting allosteric transporter interactions. Pharmacokinetic studies revealed limited in vitro metabolism and significant CNS penetration, with features predicting rapid clearance. ML352 represents a novel, potent, and specific tool for the manipulation of CHT, providing a possible platform for the development of cholinergic imaging and therapeutic agents. PMID:25560927

  18. Two plant bacteria, S. meliloti and Ca. Liberibacter asiaticus, share functional znuABC homologues that encode for a high affinity Zinc uptake system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Znu system, encoded for by znuABC, can be found in multiple genera of bacteria and has been shown to be responsible for the import of zinc under low zinc conditions. Although this high-affinity uptake system is known to be important for both growth and/or pathogenesis in bacteria, it has not bee...

  19. COMPARATIVE EFFECTS OF PARAOXON, CHLORPYRIFOS OXON AND MUSCARINIC AGONISTS ON HIGH AFFINITY CHOLINE UPTAKE IN RAT CORTICAL OR STRIATAL SYNAPTOSOMES. (R825811)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  20. Choline inhibition of amino acid transport in preimplantation mouse blastocysts

    SciTech Connect

    Campione, A.L.; Haghighat, N.; Gorman, J.; Van Winkle, L.J.

    1987-05-01

    Addition of 70 mM choline chloride to Brinster's medium (140 mM Na/sup +/) inhibited uptake of approx. 1 ..mu..M (/sup 3/H)glycine, leucine, lysine and alanine in blastocysts by about 50% each during a five-minute incubation period at 37/sup 0/C, whereas 70 mM LiCl, sodium acetate and NaCl or 140 mM mannitol had no effect. They attribute the apparent linear relationship between Gly transport in blastocysts and the square of the (Na/sup +/), observed when choline was substituted for Na/sup +/ in Brinster's medium, to concomitant, concentration-dependent enhancement and inhibition of transport by Na/sup +/ and choline, respectively. As expected, Gly uptake and the (Na/sup +/) were linearly related up to 116 mM Na/sup +/, when Na/sup +/ was replaced with Li/sup +/. The rates of Na/sup +/-independent Gly and Ala uptake were <5% and <2% of the total, respectively, and similar when either Li/sup +/ or choline replaced Na/sup +/. Therefore, neither Li/sup +/ nor choline appears to substitute for Na/sup +/ in supporting Na/sup +/-dependent transport in blastocysts. Na/sup +/-independent Leu uptake was 20 times faster than Gly or Ala uptake and appeared to be inhibited by choline in blastocysts since it was about 37% slower when choline instead of Li/sup +/ was substituted for Na/sup +/. In contrast to blastocysts, choline had no effect on amino acid transport in cleavage-stage mouse embryos. The unexpected sensitivity of transport to choline in blastocysts underscores the importance of testing the effects of this substance when it is used to replace Na/sup +/ in new transport studies.

  1. Labeled choline and phosphorylcholine: body distribution and brain autoradiography: concise communication

    SciTech Connect

    Friedland, R.P.; Mathis, C.A.; Budinger, T.F.; Moyer, B.R.; Rosen, M.

    1983-09-01

    Following intravenous injection of labeled choline or phosphorylcholine in rats and mice, the brain uptake as percent injected dose was less than 0.2% with 6-12% going to kidney and 3-6% to liver. A study of (/sup 14/C)choline autoradiography in a stump-tailed macaque demonstrated a five- to sixfold greater uptake in gray matter than in white matter. Dynamic positron imaging of (/sup 11/C)choline in a rhesus monkey demonstrated rapid brain uptake followed by rapid washout, with heavy late uptake in muscle. The use of labeled choline and choline analogs as imaging agents in human studies is constrained by the low brain uptake relative to extracerebral tissues.

  2. Labeled choline and phosphorylcholine: body distribution and brain autoradiography: concise communication

    SciTech Connect

    Friedland, R.P.; Mathis, C.A.; Budinger, T.F.; Moyer, B.R.; Rosen, M.

    1983-09-01

    Following intravenous injection of labeled choline or phosphorylcholine in rats and mice, the brain uptake as percent injected dose was less than 0.2% with 6 to 12% going to kidney and 3 to 6% to liver. A study of (/sup 14/C)choline autoradiography in a stump-tailed macaque demonstrated a five- to sixfold greater uptake in gray matter than in white matter. Dynamic positron imaging of (/sup 11/C) choline in a rhesus monkey demonstrated rapid brain uptake followed by rapid washout, with heavy late uptake in muscle. The use of labeled choline and choline analogs as imaging agents in human studies is constrained by the low brain uptake relative to extracerebral tissues.

  3. Autoradiography of phosphatidyl choline

    SciTech Connect

    Saffitz, J.E.; Gross, R.W.; Williamson, J.R.; Sobel, B.E.

    1981-03-01

    Saturated choline phosphatides are extracted during conventional tissue processing for electron microscopy. To facilitate autoradiographic subcellular localization of arrhythmogenic myocardial phospholipids, we evaluated tissue processing procedures for preservation of saturated phosphatidyl choline (PC). Suspensions, of a murine plasmacytoma were incubated with negative, unilamellar liposomes containing 14C-choline-labeled PC or 14C-1-palmitate dipalmitoyl PC. Extraction of radioactivity was monitored at each processing step by liquid scintillation spectrometry. Conventional fixation with glutaraldehyde and osmium tetroxide followed by acetone dehydration and Spurr's plastic embedding led to extraction of nearly all radioactivity. However, treatment of cells with 1.5% tannic acid after glutaraldehyde but before osmium tetroxide fixation preserved 93.1 +/- .6% of 14C-choline-labeled PC. Virtually identical results were obtained with dipalmitoyl PC. Autoradiography demonstrated no significant translocation of labeled PC from plasmacytoma cells to unlabeled avian erythrocytes, mixed in equal proportions after fixation but before dehydration and embedding.

  4. Low uptake affinity cultivars with biochar to tackle Cd-tainted rice--A field study over four rice seasons in Hunan, China.

    PubMed

    Chen, De; Guo, Hu; Li, Ruiyue; Li, Lianqing; Pan, Genxing; Chang, Andrew; Joseph, Stephen

    2016-01-15

    Biochar is becoming an environmentally friendly material for remediation of heavy metal contaminated soils and improving food safety. A field trial over four rice seasons was conducted to investigate the use of biochar and low Cd accumulating cultivars on Cd uptake in a heavy metal contaminated soil. Wheat straw derived biochar was applied at 0, 20 and 40 t ha(-1). Two rice cultivars with differing Cd accumulation abilities were selected in each season. The results showed that both biochar and low Cd affinity cultivars significantly reduced rice grain Cd accumulation. Biochar had no significant effect the first season but thereafter consistently reduced rice grain Cd by a maximum of 61, 86 and 57% over the next three seasons. Zn accumulation in the rice grains was not decreased by biochar application, although available soil Zn was sharply reduced (35-91%). Indica conventional rice cultivars had much lower Cd, but higher Zn and lower Cd/Zn ratios in the grain than indica hybrid cultivars. Biochar was more effective for mitigating grain Cd accumulation in low Cd affinity cultivars than in high affinity cultivars. Soil pH was sustainably increased (up to nearly 1 unit) while available Cd significantly decreased by a maximum of 85% after biochar addition. The translocation of Cd from rice roots to shoots was reduced from 20 to 80% by biochar. Low uptake affinity cultivars combined with biochar reduced late rice grain Cd concentration and Cd/Zn ratios by 69-80% and 72-80%, respectively. It indicated that the management of combining biochar and low Cd affinity cultivars should be an efficient way to remediate Cd contaminated rice paddies and reduce health risk associated with consuming rice from these soils. PMID:26490528

  5. Transport and phosphorylation of choline in higher plant cells. Phosphorus-31 nuclear magnetic resonance studies

    SciTech Connect

    Bligny, R.; Foray, M.F.; Roby, C.; Douce, R.

    1989-03-25

    When sycamore cells were suspended in basal medium containing choline, the latter was taken up by the cells very rapidly. A facilitated diffusion system appertained at low concentrations of choline and exhibited Michaelis-Menten kinetics. At higher choline concentrations simple diffusion appeared to be the principal mode of uptake. Addition of choline to the perfusate of compressed sycamore cells monitored by /sup 31/P NMR spectroscopy resulted in a dramatic accumulation of P-choline in the cytoplasmic compartment containing choline kinase and not in the vacuole. The total accumulation of P-choline over a 10-h period exhibited Michaelis-Menten kinetics. During this period, in the absence of Pi in the perfusion medium there was a marked depletion of glucose-6-P, and the cytoplasmic Pi resonance disappeared almost completely. When a threshold of cytoplasmic Pi was attained, the phosphorylation of choline was sustained by the continuous release of Pi from the vacuole although at a much lower rate. However, when 100 microM inorganic phosphate was present in the perfusion medium, externally added Pi was preferentially used to sustain P-choline synthesis. It is clear, therefore, that cytosolic choline kinase associated with a carrier-mediated transport system for choline uptake appeared as effective systems for continuously trapping cytoplasmic Pi including vacuolar Pi entering the cytoplasm.

  6. Prenatal choline deficiency increases choline transporter expression in the septum and hippocampus during postnatal development and in adulthood in rats.

    PubMed

    Mellott, Tiffany J; Kowall, Neil W; Lopez-Coviella, Ignacio; Blusztajn, Jan Krzysztof

    2007-06-01

    Supplementation of maternal diet with the essential nutrient, choline, during the second half of pregnancy in rats causes long-lasting improvements in spatial memory in the offspring and protects them from the memory decline characteristic of old age. In contrast, prenatal choline deficiency is associated with poor performance in certain cognitive tasks. The mechanism by which choline influences learning and memory remains unclear; however, it may involve changes to the hippocampal cholinergic system. Previously, we showed that the hippocampi of prenatally [embryonic days (E) 11-17] choline-deficient animals have increased synthesis of acetylcholine (ACh) from choline transported by the high-affinity choline transporter (CHT) and reduced ACh content relative to the control and to the E11-17 choline-supplemented rats. In the current study, we found that, during postnatal period [postnatal days (P) 18-480], prenatal choline deficiency increased the expression of CHT mRNA in the septum and CHT mRNA and protein levels in the hippocampus and altered the pattern of CHT immunoreactivity in the dentate gyrus. CHT immunoreactivity was more prominent in the inner molecular layer in prenatally choline-deficient rats compared to controls and prenatally choline-supplemented animals. In addition, in all groups, we observed a population of hilar interneurons that were CHT-immunoreactive. These neurons are the likely source of the hippocampal CHT mRNA as their number correlated with the levels of this mRNA. The abundance of hippocampal CHT mRNA rose between P1 and P24 and then declined reaching 60% of the P1 value by P90. These data show that prenatal availability of choline alters its own metabolism (i.e., CHT expression). While the upregulated CHT expression during the period of prenatal choline deficiency may be considered as a compensatory mechanism that could enhance ACh synthesis when choline supply is low, the persistent upregulation of CHT expression subsequent to the

  7. The CBL-Interacting Protein Kinase CIPK23 Regulates HAK5-Mediated High-Affinity K+ Uptake in Arabidopsis Roots1[OPEN

    PubMed Central

    Ragel, Paula; Ródenas, Reyes; García-Martín, Elena; Andrés, Zaida; Villalta, Irene; Nieves-Cordones, Manuel; Martínez, Vicente

    2015-01-01

    Plant growth and development requires efficient acquisition of essential elements. Potassium (K+) is an important macronutrient present in the soil solution at a wide range of concentrations. Regulation of the K+ uptake systems in the roots is essential to secure K+ supply. It has been shown in Arabidopsis (Arabidopsis thaliana) that when the external K+ concentration is very low (<10 µm), K+ nutrition depends exclusively on the high-affinity K+ transporter5 (HAK5). Low-K+-induced transcriptional activation of the gene encoding HAK5 has been previously reported. Here, we show the posttranscriptional regulation of HAK5 transport activity by phosphorylation. Expression in a heterologous system showed that the Ca2+ sensors calcineurin B-like (CBL1), CBL8, CBL9, and CBL10, together with CBL-interacting protein kinase23 (CIPK23), activated HAK5 in vivo. This activation produced an increase in the affinity and the Vmax of K+ transport. In vitro experiments show that the N terminus of HAK5 is phosphorylated by CIPK23. This supports the idea that phosphorylation of HAK5 induces a conformational change that increases its affinity for K+. Experiments of K+ (Rb+) uptake and growth measurements in low-K+ medium with Arabidopsis single mutants hak5, akt1, and cipk23, double mutants hak5 akt1, hak5 cipk23, and akt1 cipk23, and the triple mutant hak5 akt1 cipk23 confirmed the regulatory role of CIPK23 in planta. PMID:26474642

  8. Characterization of an AtCCX5 gene from Arabidopsis thaliana that involves in high-affinity K⁺ uptake and Na⁺ transport in yeast.

    PubMed

    Zhang, Xinxin; Zhang, Min; Takano, Tetsuo; Liu, Shenkui

    2011-10-14

    The gene for a putative cation calcium exchanger (CCX) from Arabidopsis thaliana, AtCCX5, was cloned and its function was analyzed in yeast. Green fluorescent protein-tagged AtCCX5 expressed in yeast was localized in the plasma membrane and nuclear periphery. The yeast transformants expressing AtCCX5 were created and their growth in the presence of various cations (K(+), Na(+), Ca(2+), Mg(2+), Fe(2+), Cu(2+), Co(2+), Cd(2+), Mn(2+), Ba(2+), Ni(2+), Zn(2+), and Li(+)) were analyzed. AtCCX5 expression was found to affect the response to K(+) and Na(+) in yeast. The AtCCX5 transformant also showed a little better growth to Zn(2+). The yeast mutant 9.3 expressing AtCCX5 restored growth of the mutant on medium with low K(+) (0.5mM), and also suppressed its Na(+) sensitivity. Ion uptake experiments showed that AtCCX5 mediated relatively high-affinity K(+) uptake and was also involved in Na(+) transport in yeast. Taken together, these findings suggest that the AtCCX5 is a novel transport protein involves in mediating high-affinity K(+) uptake and Na(+) transport in yeast. PMID:21945443

  9. Transgenic overexpression of the presynaptic choline transporter elevates acetylcholine levels and augments motor endurance

    PubMed Central

    Holmstrand, Ericka C.; Lund, David; Cherian, Ajeesh Koshy; Wright, Jane; Martin, Rolicia F.; Ennis, Elizabeth A.; Stanwood, Gregg D.; Sarter, Martin; Blakely, Randy D.

    2014-01-01

    The hemicholinium-3 (HC-3) sensitive, high-affinity choline transporter (CHT) sustains cholinergic signaling via the presynaptic uptake of choline derived from dietary sources or from acetylcholinesterase (AChE)-mediated hydrolysis of acetylcholine (ACh). Loss of cholinergic signaling capacity is associated with cognitive and motor deficits in humans and in animal models. Whereas genetic elimination of CHT has revealed the critical nature of CHT in maintaining ACh stores and sustaining cholinergic signaling, the consequences of elevating CHT expression have yet to be studied. Using bacterial artificial chromosome (BAC)-mediated transgenic methods, we generated mice with integrated additional copies of the mouse Slc5a7 gene. BAC–CHT mice are viable, appear to develop normally, and breed at wild-type (WT) rates. Biochemical studies revealed a 2 to 3-fold elevation in CHT protein levels in the CNS and periphery, paralleled by significant increases in [3H]HC-3 binding and synaptosomal choline transport activity. Elevations of ACh in the BAC–CHT mice occurred without compensatory changes in the activity of either choline acetyltransferase (ChAT) or AChE. Immunohistochemistry for CHT in BAC–CHT brain sections revealed markedly elevated CHT expression in the cell bodies of cholinergic neurons and in axons projecting to regions known to receive cholinergic innervation. Behaviorally, BAC–CHT mice exhibited diminished fatigue and increased speeds on the treadmill test without evidence of increased strength. Finally, BAC–CHT mice displayed elevated horizontal activity in the open field test, diminished spontaneous alteration in the Y-maze, and reduced time in the open arms of the elevated plus maze. Together, these studies provide biochemical, pharmacological and behavioral evidence that CHT protein expression and activity can be elevated beyond that seen in wild-type animals. BAC–CHT mice thus represent a novel tool to examine both the positive and negative

  10. Functional expression of choline transporter-like protein 1 (CTL1) in small cell lung carcinoma cells: a target molecule for lung cancer therapy.

    PubMed

    Inazu, Masato; Yamada, Tomoko; Kubota, Nobuo; Yamanaka, Tsuyoshi

    2013-10-01

    Choline is essential for the synthesis of the major membrane phospholipid phosphatidylcholine and the neurotransmitter acetylcholine (ACh). Elevated levels of choline and up-regulated choline kinase activity have been detected in cancer cells. Thus, the intracellular accumulation of choline through choline transporters is the rate-limiting step in phospholipid metabolism and a prerequisite for cancer cell proliferation. However, the uptake system for choline and the functional expression of choline transporters in lung cancer cells are poorly understood. We examined the molecular and functional characterization of choline uptake in the small cell lung carcinoma cell line NCI-H69. Choline uptake was saturable and mediated by a single transport system. Interestingly, removal of Na(+) from the uptake buffer strongly enhanced choline uptake. This increase in choline uptake under the Na(+)-free conditions was inhibited by dimethylamiloride (DMA), a Na(+)/H(+) exchanger (NHE) inhibitor. Various organic cations and the choline analog hemicholinium-3 (HC-3) inhibited the choline uptake and cell viability. A correlation analysis of the potencies of organic cations for the inhibition of choline uptake and cell viability showed a strong correlation (R=0.8077). RT-PCR revealed that choline transporter-like protein 1 (CTL1) mRNA and NHE1 are mainly expressed. HC-3 and CTL1 siRNA inhibited choline uptake and cell viability, and increased caspase-3/7 activity. The conversion of choline to ACh was confirmed, and this conversion was enhanced under Na(+)-free conditions, which in turn was sensitive to HC-3. These results indicate that choline uptake through CTL1 is used for ACh synthesis. Both an acetylcholinesterase inhibitor (eserine) and a butyrylcholinesterase inhibitor (ethopropazine) increased cell proliferation, and these effects were inhibited by 4-DAMP, a mAChR3 antagonist. We conclude that NCI-H69 cells express the choline transporter CTL1 which uses a directed H

  11. Characterization of an AtCCX5 gene from Arabidopsis thaliana that involves in high-affinity K{sup +} uptake and Na{sup +} transport in yeast

    SciTech Connect

    Zhang, Xinxin; Zhang, Min; Takano, Tetsuo; Liu, Shenkui

    2011-10-14

    Highlights: {yields} The AtCCX5 protein coding a putative cation calcium exchanger was characterized. {yields} AtCCX5 expressed in yeast was localized in the plasma membrane and nuclear periphery. {yields} AtCCX5 protein did not show the same transport properties as the CAXs. {yields} AtCCX5 protein involves in mediating high-affinity K{sup +} uptake in yeast. {yields} AtCCX5 protein also involves in Na{sup +} transport in yeast. -- Abstract: The gene for a putative cation calcium exchanger (CCX) from Arabidopsis thaliana, AtCCX5, was cloned and its function was analyzed in yeast. Green fluorescent protein-tagged AtCCX5 expressed in yeast was localized in the plasma membrane and nuclear periphery. The yeast transformants expressing AtCCX5 were created and their growth in the presence of various cations (K{sup +}, Na{sup +}, Ca{sup 2+}, Mg{sup 2+}, Fe{sup 2+}, Cu{sup 2+}, Co{sup 2+}, Cd{sup 2+}, Mn{sup 2+}, Ba{sup 2+}, Ni{sup 2+}, Zn{sup 2+}, and Li{sup +}) were analyzed. AtCCX5 expression was found to affect the response to K{sup +} and Na{sup +} in yeast. The AtCCX5 transformant also showed a little better growth to Zn{sup 2+}. The yeast mutant 9.3 expressing AtCCX5 restored growth of the mutant on medium with low K{sup +} (0.5 mM), and also suppressed its Na{sup +} sensitivity. Ion uptake experiments showed that AtCCX5 mediated relatively high-affinity K{sup +} uptake and was also involved in Na{sup +} transport in yeast. Taken together, these findings suggest that the AtCCX5 is a novel transport protein involves in mediating high-affinity K{sup +} uptake and Na{sup +} transport in yeast.

  12. Fluoxetine, a selective inhibitor of serotonin uptake, potentiates morphine analgesia without altering its discriminative stimulus properties or affinity for opioid receptors

    SciTech Connect

    Hynes, M.D.; Lochner, M.A.; Bemis, K.G.; Hymson, D.L.

    1985-06-17

    The analgesic effect of morphine in the rat tail jerk assay was enhanced by the serotonin uptake inhibitor, fluoxetine. Tail jerk latency was not affected by fluoxetine alone. Morphine's affinity for opioid receptors labeled in vitro with /sup 3/H-naloxone or /sup 3/H-D-Ala/sup 2/-D-Leu/sup 5/-enkephalin was not altered by fluoxetine, which has no affinity for these sites at concentrations as high as 1000 nM. In rats trained to discriminate morphine from saline, fluoxetine at doses of 5 or 10 mg/kg were recognized as saline. Increasing the fluoxetine dose to 20 mg/kg did not result in generalization to either saline or morphine. The dose response curve for morphine generalization was not significantly altered by fluoxetine doses of 5 or 10 mg/kg. Those rats treated with the combination of morphine and 20 mg/kg of fluoxetine did not exhibit saline or morphine appropriate responding. Fluoxetine potentiates the analgesic properties of morphine without enhancing its affinity for opioid receptors or its discriminative stimulus properties. 30 references, 2 figures, 2 tables.

  13. Distribution and ultrastructure of neurons in opossum piriform cortex displaying immunoreactivity to GABA and GAD and high-affinity tritiated GABA uptake

    SciTech Connect

    Haberly, L.B.; Hansen, D.J.; Feig, S.L.; Presto, S.

    1987-12-08

    GABAergic neurons have been identified in the piriform cortex of the opossum at light and electron microscopic levels by immunocytochemical localization of GABA and the GABA-synthesizing enzyme glutamic acid decarboxylase and by autoradiographic visualization of high-affinity /sup 3/H-GABA uptake. Four major neuron populations have been distinguished on the basis of soma size, shape, and segregation at specific depths and locations: large horizontal cells in layer Ia of the anterior piriform cortex, small globular cells with thin dendrites concentrated in layers Ib and II of the posterior piriform cortex, and multipolar and fusiform cells concentrated in the deep part of layer III in anterior and posterior parts of the piriform cortex and the subjacent endopiriform nucleus. All four populations were well visualized with both antisera, but the large layer Ia horizontal cells displayed only very light /sup 3/H-GABA uptake, thus suggesting a lack of local axon collaterals or lack of high-affinity GABA uptake sites. The large, ultrastructurally distinctive somata of layer Ia horizontal cells receive a very small number of symmetrical synapses; the thin, axonlike dendrites of small globular cells are exclusively postsynaptic and receive large numbers of both symmetrical and asymmetrical synapses, in contrast to somata which receive a small number of both types; and the deep multipolar and fusiform cells receive a highly variable number of symmetrical and asymmetrical synapses on somata and proximal dendrites. Labeled puncta of axon terminal dimensions were found in large numbers in the neuropil surrounding pyramidal cell somata in layer II and in the endopiriform nucleus. Moderately large numbers of labeled puncta were found in layer I at the depth of pyramidal cell apical dendrites with greater numbers in layer Ia at the depth of distal apical segments than in layer Ib.

  14. High Ca(2+) reverts the repression of high-affinity K(+) uptake produced by Na(+) in Solanum lycopersycum L. (var. microtom) plants.

    PubMed

    Bacha, Hayet; Ródenas, Reyes; López-Gómez, Elvira; García-Legaz, Manuel Francisco; Nieves-Cordones, Manuel; Rivero, Rosa M; Martínez, Vicente; Botella, M Ángeles; Rubio, Francisco

    2015-05-15

    Potassium (K(+)) is an essential nutrient for plants which is acquired by plant roots through the operation of specific transport systems. Abiotic stress conditions such as salinity impair K(+) nutrition because, in addition to other effects, high salt concentrations in the solution bathing the roots inhibit K(+) uptake systems. This detrimental effect of salinity is exacerbated when external K(+) is very low and the only system capable of mediating K(+) uptake is one with high-affinity for K(+), as that mediated by transporters of the HAK5 type. Increasing external Ca(2+) has been shown to improve K(+) nutrition under salinity and, although the specific mechanisms for this beneficial effect are largely unknown, they are beginning to be understood. The genes encoding the HAK5 transporters are induced by K(+) starvation and repressed by long-term exposure to high Na(+). This occurs in parallel with the hyperpolarization and depolarization of root cell membrane potential. In the present study it is shown in tomato plants that the presence of high Ca(2+) during the K(+) starvation period that leads to LeHAK5 induction, counteracts the repression exerted by high Na(+). High Ca(2+) reduces the Na(+)-induced plasma membrane depolarization of root cells, resorting one of the putative first steps in the low-K(+) signal cascade. This allows proper LeHAK5 expression and functional high-affinity K(+) uptake at the roots. Thus, the maintenance of HAK5-mediated K(+) nutrition under salinity by high Ca(2+) can be regarded as a specific beneficial effect of Ca(2+) contributing to salt tolerance in plants. PMID:25901651

  15. High affinity (/sup 3/H). beta. -Alanine uptake by scar margins of ferric chloride-induced epileptogenic foci in rat isocortex

    SciTech Connect

    Robitaille, Y.; Sherwin, A.

    1984-07-01

    Cortical astrocytes of normal mammalian brain are endowed with a high affinity uptake system for ..beta..-Alanine which is competitively inhibited by gamma aminobutyric acid (GABA), a neurotransmitter strongly implicated in epileptogenesis. The authors evaluated (/sup 3/H) ..beta..-Alanine uptake by reactive astrocytes proliferating within scar of epileptogenic foci induced in rat motor cortex by microinjections of 100 mM ferric chloride. Following in vitro incubation of scar tissue with (/sup 3/H) ..beta..-Alanine, ultrastructural morphometry of grain patterns at 5, 30 and 120 days post injection revealed early and significant grain count increases over astroglial processes, predominantly those related to perivascular glial end-feet. Astrocytic cell body and endothelial cell counts showed a more gradual and stepwise increase. Similar data were obtained by comparing visual and edited mean astrocytic grain counts. These results suggest that the enhanced uptake of reactive astrocytes may reflect a marked decrease of inhibitory GABAergic neurons within ferric chloride-induced scars. 7 figures, 1 table.

  16. Choline molecular imaging with small-animal PET for monitoring tumor cellular response to photodynamic therapy of cancer

    NASA Astrophysics Data System (ADS)

    Fei, Baowei; Wang, Hesheng; Wu, Chunying; Meyers, Joseph; Xue, Liang-Yan; MacLennan, Gregory; Schluchter, Mark

    2009-02-01

    We are developing and evaluating choline molecular imaging with positron emission tomography (PET) for monitoring tumor response to photodynamic therapy (PDT) in animal models. Human prostate cancer (PC-3) was studied in athymic nude mice. A second-generation photosensitizer Pc 4 was used for PDT in tumor-bearing mice. MicroPET images with 11C-choline were acquired before PDT and 48 h after PDT. Time-activity curves of 11C-choline uptake were analyzed before and after PDT. For treated tumors, normalized choline uptake decreased significantly 48 h after PDT, compared to the same tumors pre-PDT (p <~ 0.001). However, for the control tumors, normalized choline uptake increased significantly (p <~ 0.001). PET imaging with 11C-choline is sensitive to detect early tumor response to PDT in the animal model of human prostate cancer.

  17. Transport and Metabolism of Radiolabeled Choline in Hepatocellular Carcinoma

    PubMed Central

    Kuang, Yu; Salem, Nicolas; Corn, David J.; Erowku, Bernadette; Tian, Haibin; Wang, Fangjing; Lee, Zhenghong

    2010-01-01

    Objectives Altered choline (Cho) metabolism in cancerous cells can be used as a basis for molecular imaging with PET using radiolabeled Cho. In this study, the metabolism of tracer Cho was investigated in a woodchuck hepatocellular carcinoma (HCC) cell line (WCH17) and in freshly-derived rat hepatocytes. The transporter responsible for [11C]-Cho uptake in HCC was also characterized in WCH17 cells. The study helped to define the specific mechanisms responsible for radio-Cho uptake seen on the PET images of primary liver cancer such as HCC. Methods Cells were pulsed with [14C]-Cho for 5 min and chased for varying durations in cold media to simulate the rapid circulation and clearance of [11C]-Cho. Radioactive metabolites were extracted and analyzed by radio-HPLC and radio-TLC. The Cho transporter (ChoT) was characterized in WCH17 cells. Results WCH17 cells showed higher 14C uptake than rat primary hepatocytes. [14C]-Phosphocholine (PC) was the major metabolite in WCH17. In contrast, the intracellular Cho in primary hepatocytes was found to be oxidized to betaine (partially released into media) and to a less degree, phosphorylated to PC. [14C]-Cho uptake by WCH17 cells was found to have both facilitative transport and non-facilitative diffusion components. The facilitative transport was characterized by Na+ dependence and low affinity (Km = 28.59 ± 6.75 μM) with partial energy dependence. In contrast, ChoT in primary hepatocytes is Na+ independent and low affinity. Conclusions Our data suggest that transport and phosphorylation of Cho are responsible for the tracer accumulation during [11C]-Cho PET imaging of HCC. WCH17 cells incorporate [14C]-Cho preferentially into PC. Conversion of [14C]-PC into phosphatidylcholine occurred slowly in vitro. Basal oxidation and phosphorylation activities in surrounding hepatic tissue contribute to the background seen in [11C]-Cho PET images. PMID:20698576

  18. Comparative genomics and mutagenesis analyses of choline metabolism in the marine R oseobacter clade

    PubMed Central

    Lidbury, Ian; Kimberley, George; Scanlan, David J.; Murrell, J. Colin

    2015-01-01

    Summary Choline is ubiquitous in marine eukaryotes and appears to be widely distributed in surface marine waters; however, its metabolism by marine bacteria is poorly understood. Here, using comparative genomics and molecular genetic approaches, we reveal that the capacity for choline catabolism is widespread in marine heterotrophs of the marine Roseobacter clade (MRC). Using the model bacterium R uegeria pomeroyi, we confirm that the bet A, bet B and bet C genes, encoding choline dehydrogenase, betaine aldehyde dehydrogenase and choline sulfatase, respectively, are involved in choline metabolism. The bet T gene, encoding an organic solute transporter, was essential for the rapid uptake of choline but not glycine betaine (GBT). Growth of choline and GBT as a sole carbon source resulted in the re‐mineralization of these nitrogen‐rich compounds into ammonium. Oxidation of the methyl groups from choline requires formyltetrahydrofolate synthetase encoded by fhs in R . pomeroyi, deletion of which resulted in incomplete degradation of GBT. We demonstrate that this was due to an imbalance in the supply of reducing equivalents required for choline catabolism, which can be alleviated by the addition of formate. Together, our results demonstrate that choline metabolism is ubiquitous in the MRC and reveal the role of Fhs in methyl group oxidation in R . pomeroyi. PMID:26058574

  19. Role of Fig1, a Component of the Low-Affinity Calcium Uptake System, in Growth and Sexual Development of Filamentous Fungi

    PubMed Central

    Cavinder, Brad

    2012-01-01

    The function of Fig1, a transmembrane protein of the low-affinity calcium uptake system (LACS) in fungi, was examined for its role in the growth and development of the plant pathogen Fusarium graminearum. The Δfig1 mutants failed to produce mature perithecia, and sexual development was halted prior to the formation of perithecium initials. The loss of Fig1 function also resulted in a reduced vegetative growth rate. Macroconidium production was reduced 70-fold in the Δfig1 mutants compared to the wild type. The function of the high-affinity calcium uptake system (HACS), comprised of the Ca2+ channels Mid1 and Cch1, was previously characterized for F. graminearum. To better understand the roles of the LACS and the HACS, Δfig1 Δmid1, Δfig1 Δcch1, and Δfig1 Δmid1 Δcch1 double and triple mutants were generated, and the phenotypes of these mutants were more severe than those of the Δfig1 mutants. Pathogenicity on wheat was unaffected for the Δfig1 mutants, but the Δfig1 Δmid1, Δfig1 Δcch1, and Δfig1 Δmid1 Δcch1 mutants, lacking both LACS and HACS functions, had reduced pathogenicity. Additionally, Δfig1 mutants of Neurospora crassa were examined and did not affect filamentous growth or female fertility in a Δfig1 mating type A strain, but the Δfig1 mating type a strain failed to produce fertile fruiting bodies. These results are the first report of Fig1 function in filamentous ascomycetes and expand its role to include complex fruiting body and ascus development. PMID:22635922

  20. High-Affinity Manganese Uptake by the Metal Transporter NRAMP1 Is Essential for Arabidopsis Growth in Low Manganese Conditions[C][W

    PubMed Central

    Cailliatte, Rémy; Schikora, Adam; Briat, Jean-François; Mari, Stéphane; Curie, Catherine

    2010-01-01

    In contrast with many other essential metals, the mechanisms of Mn acquisition in higher eukaryotes are seldom studied and poorly understood. We show here that Arabidopsis thaliana relies on a high-affinity uptake system to acquire Mn from the soil in conditions of low Mn availability and that this activity is catalyzed by the divalent metal transporter NRAMP1 (for Natural Resistance Associated Macrophage Protein 1). The nramp1-1 loss-of-function mutant grows poorly, contains less Mn than the wild type, and fails to take up Mn in conditions of Mn limitation, thus demonstrating that NRAMP1 is the major high-affinity Mn transporter in Arabidopsis. Based on confocal microscopy observation of an NRAMP1-green fluorescent protein fusion, we established that NRAMP1 is localized to the plasma membrane. Consistent with its function in Mn acquisition from the soil, NRAMP1 expression is restricted to the root and stimulated by Mn deficiency. Finally, we show that NRAMP1 restores the capacity of the iron-regulated transporter1 mutant to take up iron and cobalt, indicating that NRAMP1 has a broad selectivity in vivo. The role of transporters of the NRAMP family is well established in higher eukaryotes for iron but has been controversial for Mn. This study demonstrates that NRAMP1 is a physiological manganese transporter in Arabidopsis. PMID:20228245

  1. Arabidopsis IRT2 cooperates with the high-affinity iron uptake system to maintain iron homeostasis in root epidermal cells.

    PubMed

    Vert, Grégory; Barberon, Marie; Zelazny, Enric; Séguéla, Mathilde; Briat, Jean-François; Curie, Catherine

    2009-05-01

    Iron is an essential nutrient for all organisms but toxic when present in excess. Consequently, plants carefully regulate their iron uptake, dependent on the FRO2 ferric reductase and the IRT1 transporter, to control its homeostasis. Arabidopsis IRT2 gene, whose expression is induced in root epidermis upon iron deprivation, was shown to encode a functional iron/zinc transporter in yeast, and proposed to function in iron acquisition from the soil. In this study, we demonstrate that, unlike its close homolog IRT1, IRT2 is not involved in iron absorption from the soil since overexpression of IRT2 does not rescue the iron uptake defect of irt1-1 mutant and since a null irt2 mutant shows no chlorosis in low iron. Consistently, an IRT2-green fluorescent fusion protein, transiently expressed in culture cells, localizes to intracellular vesicles. However, IRT2 appears strictly co-regulated with FRO2 and IRT1, supporting the view that IRT2 is an integral component of the root response to iron deficiency in root epidermal cells. We propose a model where IRT2 likely prevents toxicity from IRT1-dependent iron fluxes in epidermal cells, through compartmentalization. PMID:19252923

  2. Incidental finding of parathyroid adenoma with 11C-choline PET/CT.

    PubMed

    Mapelli, Paola; Busnardo, Elena; Magnani, Patrizia; Freschi, Massimo; Picchio, Maria; Gianolli, Luigi; Messa, Cristina

    2012-06-01

    Positron emission tomography/computed tomography (PET/CT) with 11C-choline is an established diagnostic tool for restaging prostate cancer patients with biochemical failure after primary treatment. In the present case, 11C-choline PET/CT was performed in a prostate cancer patient with skeletal metastases, treated with hormonal therapy. In addition to the detection of pathologic uptake at prostate and vertebra, 11C-choline uptake occurred in the neck. The finding was suggestive for a parathyroid adenoma on subsequent ultrasound, then finally confirmed by parathyroid scintigraphy and histopathological analysis performed after hemithyroidectomy. PMID:22614195

  3. Sex-dependent actions of amyloid beta peptides on hippocampal choline carriers of postnatal rats.

    PubMed

    Kristofiková, Z; Rícný, J; Kozmiková, I; Rípová, D; Zach, P; Klaschka, J

    2006-03-01

    It is suggested that amyloid beta peptides (Abeta) play a role in the pathogenesis of Alzheimer disease but their physiological function is still unknown. However, low pM-nM concentrations mediate a hypofunction of a basal forebrain cholinergic system without marked signs of neurotoxicity. In this study, we compared in vitro effects of soluble nonaggregated human Abeta 1-40 and 1-42 either on synaptosomal hemicholinium-3 sensitive choline carriers or on membrane fluidity in hippocampi of male and female Wistar rats aged 7 and 14 days or 2-3 months. The results indicate age- and sex-dependent effects mediated by peptides at nM concentrations but no significant differences between both fragments. Namely, opposite actions were observed in 14-day (the increase in the choline uptake and membrane fluidity) when compared to 7-day old and adult males (the mild drops). Lineweaver-Burk plot analysis revealed that the enhancement of the high-affinity choline transport in 14-day old males occurs via alterations in K (M )and the change was accompanied by a mild increase in the specific binding of [3H]hemicholinium-3. On the other hand, no age-dependent differences were found in females. Rat Abeta 1-40 mediated similar effects on 14-day old rats as the corresponding human fragment. Moreover, higher levels of soluble peptides were detected in immature when compared to mature male brains by means of competitive ELISA. Our study indicates that Abeta could play a role in postnatal sexual differentiation of hippocampal cholinergic system. PMID:16733811

  4. Alterations of choline phospholipid metabolism in endometrial cancer are caused by choline kinase alpha overexpression and a hyperactivated deacylation pathway.

    PubMed

    Trousil, Sebastian; Lee, Patrizia; Pinato, David J; Ellis, James K; Dina, Roberto; Aboagye, Eric O; Keun, Hector C; Sharma, Rohini

    2014-12-01

    Metabolic rearrangements subsequent to malignant transformation are not well characterized in endometrial cancer. Identification of altered metabolites could facilitate imaging-guided diagnosis, treatment surveillance, and help to identify new therapeutic options. Here, we used high-resolution magic angle spinning magnetic resonance mass spectroscopy on endometrial cancer surgical specimens and normal endometrial tissue to investigate the key modulators that might explain metabolic changes, incorporating additional investigations using qRT-PCR, Western blotting, tissue microarrays (TMA), and uptake assays of [(3)H]-labeled choline. Lipid metabolism was severely dysregulated in endometrial cancer with various amino acids, inositols, nucleobases, and glutathione also altered. Among the most important lipid-related alterations were increased phosphocholine levels (increased 70% in endometrial cancer). Mechanistic investigations revealed that changes were not due to altered choline transporter expression, but rather due to increased expression of choline kinase α (CHKA) and an activated deacylation pathway, as indicated by upregulated expression of the catabolic enzymes LYPLA1, LYPLA2, and GPCPD1. We confirmed the significance of CHKA overexpression on a TMA, including a large series of endometrial hyperplasia, atypical hyperplasia, and adenocarcinoma tissues, supporting a role for CHKA in malignant transformation. Finally, we documented several-fold increases in the uptake of [(3)H]choline in endometrial cancer cell lines compared with normal endometrial stromal cells. Our results validate deregulated choline biochemistry as an important source of noninvasive imaging biomarkers for endometrial cancer. PMID:25267063

  5. Non-covalent interaction between dietary stilbenoids and human serum albumin: Structure-affinity relationship, and its influence on the stability, free radical scavenging activity and cell uptake of stilbenoids.

    PubMed

    Cao, Hui; Jia, Xueping; Shi, Jian; Xiao, Jianbo; Chen, Xiaoqing

    2016-07-01

    Dietary stilbenoids are associated with many benefits for human health, which depend on their bioavailability and bioaccessibility. The stilbenoid-human serum albumin (HSA) interactions are investigated to explore the structure-affinity relationship and influence on the stability, free radical scavenging activity and cell uptake of stilbenoids. The structure-affinity relationship of the stilbenoids-HSA interaction was found as: (1) the methoxylation enhanced the affinity, (2) an additional hydroxyl group increases the affinity and (3) the glycosylation significantly weakened the affinity. HSA obviously masked the free radical scavenging potential of stilbenoids. The stabilities of stilbenoids in different medium were determined as: HSA solution>human plasma>Dulbecco's modified Eagle's medium. It appears that the milk enhanced the cell uptake of stilbenoids with multi-hydroxyl groups and weakened the cell uptake of stilbenoids with methoxyl group on EA.hy 926 endothelial cells. The stilbenoids are hardly absorbed by human umbilical vein endothelial cells in the presence of milk. PMID:26920308

  6. High affinity (3)H-phenylalanine uptake by brush border membrane vesicles from whole larvae of Aedes aegypti (AaBBMVw).

    PubMed

    Sterling, Kenneth M; Okech, Bernard A; Xiang, Minghui A; Linser, Paul J; Price, David A; Vanekeris, Leslie; Becnel, James J; Harvey, William R

    2012-04-01

    Brush border membrane vesicles from whole Aedes aegypti larvae (AaBBMVw) are confirmed to be valid preparations for membrane transport studies. The Abdul-Rauf and Ellar method was used to isolate AaBBMVw that were frozen, stored for several months, transported to a distant site, thawed and used to study Na(+)-coupled, (3)H-labeled, phenylalanine (Phe) uptake. The affinity for all components of the uptake was very high with half maximal values in the sub-micromolar range. By contrast a K(0.5)(Phe) of 0.2mM and a K(0.5)(Na) of 26 mM were calculated from Phe-induced electrical currents in Xenopus oocytes that were heterologously expressing the Anopheles gambiae symporter (co-transporter), AgNAT8, in a buffer with 98 mM Na(+). What accounts for the >1000-fold discrepancy in affinity for substrates between the BBMV and oocyte experiments? Is it because Ae. aegypti were used to isolate BBMVw whereas An. gambiae were used to transfect oocytes? More likely, it is because BBMVw were exposed to [Na(+)] in the micromolar range with the transporter(s) being surrounded by native lipids. By contrast, the oocyte measurements were made at [Na(+)] 100,000 times higher with AgNAT8 surrounded by foreign frog lipids. The results show that AaBBMVw are osmotically sealed; the time-course has a Na(+)-induced overshoot, the pH optimum is ∼7 and the K(0.5) values for Phe and Na(+) are very low. The transport is virtually unchanged when Na(+) is replaced by K(+) or Li(+) but decreased by Rb(+). This approach to resolving discrepancies between electrical data on solute transporters such as AgNAT8 that are over-expressed in oocytes and flux data on corresponding transporters that are highly expressed in native membrane vesicles, may serve as a model for similar studies that add membrane biochemistry to molecular biology in efforts to identify targets for the development of new methods to control disease-vector mosquitoes. PMID:22251673

  7. Transport of choline against a concentration gradient by isolated granular pneumocytes

    SciTech Connect

    Reicherter, J.; Kleinzeller, A.; Chander, A.; Fisher, A.B.

    1987-05-01

    Uptake of /sup 3/H-choline was studied in granular pneumocytes isolated from rat lungs by tryptic digestion, attached to Nucleopore membranes coated with rat-tail collagen, and maintained in primary culture for 24 hours. 3-0-Methyl-(/sup 14/C)-glucose was used as a tracer to calculate H/sub 2/O space of cells. To stop reaction, cells were quenched in methanol and extracted to give lipid, free-choline, and phosphorylated choline fractions. With 5 uM external choline, cellular accumulation in all three fractions was linear for 30 min and free choline reached a 9-fold accumulation (inside/outside) ratio. With 0.1 mM external choline, the accumulation ratio reached a constant value of approx. 3 after 2 min incubation. With 1.5 min incubation, cell (choline) reached a plateau at approx. 30 uM external choline with a Km for uptake of approx. 8 uM. Efflux from preloaded cells showed two cellular components with a rate constant for the slow component of 0.031/sec. Uptake was inhibited 52% by hemicholinium-3 (10/sup -4/ M), 41% by N-ethylmaleimide (10/sup -5/M), 30-50% by mitochondrial inhibitors, 15% by ouabain (0.5 mM) and 85% by incubation at 4/sup 0/. Omitting Na/sup +/ had no effect on uptake. These results indicate that granular pneumocytes accumulate choline from the medium against a concentration gradient by an energy-dependent process indicating active transport of this substrate.

  8. In Vivo Analysis of HPr Reveals a Fructose-Specific Phosphotransferase System That Confers High-Affinity Uptake in Streptomyces coelicolor

    PubMed Central

    Nothaft, Harald; Parche, Stephan; Kamionka, Annette; Titgemeyer, Fritz

    2003-01-01

    HPr, the histidine-containing phosphocarrier protein of the bacterial phosphotransferase system (PTS), serves multiple functions in carbohydrate uptake and carbon source regulation in low-G+C-content gram-positive bacteria and in gram-negative bacteria. To assess the role of HPr in the high-G+C-content gram-positive organism Streptomyces coelicolor, the encoding gene, ptsH, was deleted. The ptsH mutant BAP1 was impaired in fructose utilization, while growth on other carbon sources was not affected. Uptake assays revealed that BAP1 could not transport appreciable amounts of fructose, while the wild type showed inducible high-affinity fructose transport with an apparent Km of 2 μM. Complementation and reconstitution experiments demonstrated that HPr is indispensable for a fructose-specific PTS activity. Investigation of the putative fruKA gene locus led to identification of the fructose-specific enzyme II permease encoded by the fruA gene. Synthesis of HPr was not specifically enhanced in fructose-grown cells and occurred also in the presence of non-PTS carbon sources. Transcriptional analysis of ptsH revealed two promoters that are carbon source regulated. In contrast to what happens in other bacteria, glucose repression of glycerol kinase was still operative in a ptsH background, which suggests that HPr is not involved in general carbon regulation. However, fructose repression of glycerol kinase was lost in BAP1, indicating that the fructose-PTS is required for transduction of the signal. This study provides the first molecular genetic evidence of a physiological role of the PTS in S. coelicolor. PMID:12533468

  9. 21 CFR 573.300 - Choline xanthate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Choline xanthate. 573.300 Section 573.300 Food and... Listing § 573.300 Choline xanthate. Choline xanthate may be safely used as a component of animal feed as an added source of choline to supplement the diets of poultry, ruminants, and swine in...

  10. 21 CFR 573.300 - Choline xanthate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Choline xanthate. 573.300 Section 573.300 Food and... Listing § 573.300 Choline xanthate. Choline xanthate may be safely used as a component of animal feed as an added source of choline to supplement the diets of poultry, ruminants, and swine in...

  11. 21 CFR 573.300 - Choline xanthate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Choline xanthate. 573.300 Section 573.300 Food and... Listing § 573.300 Choline xanthate. Choline xanthate may be safely used as a component of animal feed as an added source of choline to supplement the diets of poultry, ruminants, and swine in...

  12. Two Plant Bacteria, S. meliloti and Ca. Liberibacter asiaticus, Share Functional znuABC Homologues That Encode for a High Affinity Zinc Uptake System

    PubMed Central

    Vahling-Armstrong, Cheryl M.; Zhou, Huasong; Benyon, Lesley; Morgan, J. Kent; Duan, Yongping

    2012-01-01

    The Znu system, encoded for by znuABC, can be found in multiple genera of bacteria and has been shown to be responsible for the import of zinc under low zinc conditions. Although this high-affinity uptake system is known to be important for both growth and/or pathogenesis in bacteria, it has not been functionally characterized in a plant-associated bacterium. A single homologue of this system has been identified in the plant endosymbiont, Sinorhizobium meliloti, while two homologous systems were found in the destructive citrus pathogen, Candidatus Liberibacter asiaticus. To understand the role of these protein homologues, a complementation assay was devised allowing the individual genes that comprise the system to be assayed independently for their ability to reinstate a partially-inactivated Znu system. Results from the assays have demonstrated that although all of the genes from S. meliloti were able to restore activity, only one of the two Ca. Liberibacter asiaticus encoded gene clusters contained genes that were able to functionally complement the system. Additional analysis of the gene clusters reveals that distinct modes of regulation may also exist between the Ca. Liberibacter asiaticus and S. meliloti import systems despite the intracellular-plant niche common to both of these bacteria. PMID:22655039

  13. Distribution and metabolism of intravenously administered choline[methyl- 3-H] and synthesis in vivo of acetylcholine in various tissues of guinea pigs.

    PubMed

    Haubrich, D R; Wang, P F; Wedeking, P W

    1975-04-01

    The biosynthesis of acetylcholine and the fate of intravenously administered choline [methyl- 3-H] were studied in guinea pigs anesthetized with pentobarbital. Choline and acetylcholine were isolated by paper electrophoresis and estimated by use of a specific enzymatic (choline kinase) - radioisotopic assay. The concentration of acetylcholine ranged from 25.5 to 1.1 nmol/g in the following tissues (in order of decreasing concentration): duodenum, corpus striatum, stomach, cerebral cortex, spinal cord, abdominal fat, submaxillary gland, kidney, adrenal gland, spleen, liver, lung, heart and diaphragm. Choline [methyl- 3-H] was converted in the tissues to acetylcholine within 3 minutes after intravenous administration of the precursor. Virtually all the radioactivity in plasma at that time was present as free choline, suggesting that free choline from plasma is the immediate precursor for acetylcholine synthesized in the tissues cited. The concentration of free choline in tissues ranged from 344 nmol/g in adrenals to 40 nmol/g in heart, while that in plasma was 15 nmol/g. The initial half-life of choline in plasma, estimated from the rate of disappearance of choline after intravenous administration of either a tracer dose of choline [methyl- 3-H] (0.031 mumol/kg) or a high dose of choline chloride (200 mumol/kg), was less than 1 minute. This rapid removal of choline from plasma resulted from uptake (or binding) by tissues, with kidney and liver removing about 50% of the administered dose of choline [methyl- 3-H] within 3 minutes after its administration. Uptake of choline occurred in all tissues cited above, but there was a 20-fold difference in the uptake by the most active tissues (kidney and adrenals), as compared to that of the least active (central nervous system). Within 60 minutes after administration of choline [methyl- 3-H], most of the radioactive choline taken up by tissues had been converted to organic-soluble metabolites and to water-soluble metabolites

  14. Compartmental model of 18F-choline

    NASA Astrophysics Data System (ADS)

    Janzen, T.; Tavola, F.; Giussani, A.; Cantone, M. C.; Uusijärvi, H.; Mattsson, S.; Zankl, M.; Petoussi-Henß, N.; Hoeschen, C.

    2010-03-01

    The MADEIRA Project (Minimizing Activity and Dose with Enhanced Image quality by Radiopharmaceutical Administrations), aims to improve the efficacy and safety of 3D functional imaging by optimizing, among others, the knowledge of the temporal variation of the radiopharmaceuticals' uptake in and clearance from tumor and healthy tissues. With the help of compartmental modeling it is intended to optimize the time schedule for data collection and improve the evaluation of the organ doses to the patients. Administration of 18F-choline to screen for recurrence or the occurrence of metastases in prostate cancer patients is one of the diagnostic applications under consideration in the frame of the project. PET and CT images have been acquired up to four hours after injection of 18F-choline. Additionally blood and urine samples have been collected and measured in a gamma counter. The radioactivity concentration in different organs and data of plasma clearance and elimination into urine were used to set-up a compartmental model of the biokinetics of the radiopharmaceutical. It features a central compartment (blood) exchanging with organs. The structure describes explicitly liver, kidneys, spleen, plasma and bladder as separate units with a forcing function approach. The model is presented together with an evaluation of the individual and population kinetic parameters, and a revised time schedule for data collection is proposed. This optimized time schedule will be validated in a further set of patient studies.

  15. Stress-induced stimulation of choline transport in cultured choroid plexus epithelium exposed to low concentrations of cadmium

    PubMed Central

    Young, Robin K.

    2013-01-01

    The choroid plexus epithelium forms the blood-cerebrospinal fluid barrier and accumulates essential minerals and heavy metals. Choroid plexus is cited as being a “sink” for heavy metals and excess minerals, serving to minimize accumulation of these potentially toxic agents in the brain. An understanding of how low doses of contaminant metals might alter transport of other solutes in the choroid plexus is limited. Using primary cultures of epithelial cells isolated from neonatal rat choroid plexus, our objective was to characterize modulation of apical uptake of the model organic cation choline elicited by low concentrations of the contaminant metal cadmium (CdCl2). At 50–1,000 nM, cadmium did not directly decrease or increase 30-min apical uptake of 10 μM [3H]choline. However, extended exposure to 250–500 nM cadmium increased [3H]choline uptake by as much as 75% without marked cytotoxicity. In addition, cadmium induced heat shock protein 70 and heme oxygenase-1 protein expression and markedly induced metallothionein gene expression. The antioxidant N-acetylcysteine attenuated stimulation of choline uptake and induction of stress proteins. Conversely, an inhibitor of glutathione synthesis l-buthionine-sulfoximine (BSO) enhanced stimulation of choline uptake and induction of stress proteins. Cadmium also activated ERK1/2 MAP kinase. The MEK1 inhibitor PD98059 diminished ERK1/2 activation and attenuated stimulation of choline uptake. Furthermore, inhibition of ERK1/2 activation abated stimulation of choline uptake in cells exposed to cadmium with BSO. These data indicate that in the choroid plexus, exposure to low concentrations of cadmium may induce oxidative stress and consequently stimulate apical choline transport through activation of ERK1/2 MAP kinase. PMID:24401988

  16. High-Resolution Optical Molecular Imaging of Changes in Choline Metabolism in Oral Neoplasia1

    PubMed Central

    Luo, Zhen; Loja, Melissa; Farwell, D Greg; Luu, Quang C; Donald, Paul J; Amott, Deborah; Gandour-Edwards, Regina; Nitin, Nitin

    2013-01-01

    This study was aimed at developing an optical molecular imaging approach to measure differences in uptake and intracellular retention of choline in clinically isolated tissue biopsies from head and neck cancer patients. An optically detectable analogue of choline (propargyl choline) was synthesized and evaluated in 2D and 3D models and clinically isolated paired biopsies (n = 22 biopsies). Fluorescence contrast between clinically abnormal and normal tissues based on uptake and intracellular retention of propargyl choline was measured and correlated with pathologic diagnosis. Results in 2D and 3D models demonstrated a rapid uptake of propargyl choline in cancer cells, uniform permeation in tissue models, and specific detection of intracellular entrapped propargyl choline using the click chemistry reaction with an azide-modified Alexa 488 dye. Fluorescence imaging measurements following topical delivery of propargyl choline in clinically isolated biopsies showed that the mean fluorescence intensity (MFI) of neoplastic tissues was four-fold to five-fold higher than the MFI of clinically and pathologically normal samples. This difference in fluorescence contrast was measured on the basis of comparison of paired biopsy sets isolated from individual patients as well as comparison of clinically abnormal and normal biopsies independent of anatomic locations in the head and neck cavity and across diverse patients. In conclusion, a novel imaging approach based on monoalkyne-modified choline was developed and validated using cell and tissue models. Results in clinically isolated tissue biopsies demonstrate a significant fluorescent contrast between neoplastic and normal tissues and illustrate high specificity of the optical imaging approach. PMID:23418615

  17. Energy for Wild-Type Acetylcholine Receptor Channel Gating from Different Choline Derivatives

    PubMed Central

    Bruhova, Iva; Gregg, Timothy; Auerbach, Anthony

    2013-01-01

    Agonists, including the neurotransmitter acetylcholine (ACh), bind at two sites in the neuromuscular ACh receptor channel (AChR) to promote a reversible, global change in protein conformation that regulates the flow of ions across the muscle cell membrane. In the synaptic cleft, ACh is hydrolyzed to acetate and choline. Replacement of the transmitter’s ester acetyl group with a hydroxyl (ACh→choline) results in a +1.8 kcal/mol reduction in the energy for gating generated by each agonist molecule from a low- to high-affinity change of the transmitter binding site (ΔGB). To understand the distinct actions of structurally related agonist molecules, we measured ΔGB for 10 related choline derivatives. Replacing the hydroxyl group of choline with different substituents, such as hydrogen, chloride, methyl, or amine, increased the energy for gating (i.e., it made ΔGB more negative relative to choline). Extending the ethyl hydroxide tail of choline to propyl and butyl hydroxide also increased this energy. Our findings reveal the amount of energy that is available for the AChR conformational change provided by different, structurally related agonists. We speculate that a hydrogen bond between the choline hydroxyl and the backbone carbonyl of αW149 positions this agonist’s quaternary ammonium group so as to reduce the cation-π interaction between this moiety and the aromatic groups at the binding site. PMID:23442907

  18. Choline: An Essential Nutrient for Public Health

    PubMed Central

    da Costa, Kerry-Ann

    2009-01-01

    Choline was officially recognized as an essential nutrient by the Institute of Medicine (IOM) in 1998. There is a significant variation in the dietary requirement for choline that can be explained by common genetic polymorphisms. Because of its wide-ranging roles in human metabolism, from cell structure to neurotransmitter synthesis, choline-deficiency is now thought to have an impact on diseases such as liver disease, atherosclerosis and possibly neurological disorders. Choline is found in a wide variety of foods. Egg yolks are the most concentrated source of choline in the American diet, providing 680 milligrams per 100 grams. Mean choline intakes for older children, men, women and pregnant women are far below the Adequate Intake established by the IOM. Given the importance of choline in a wide range of critical functions in the human body, coupled with less than optimal intakes among the population, dietary guidance should be developed to encourage the intake of choline-rich foods. PMID:19906248

  19. Choline transport in the isolated rabbit corneal epithelium

    SciTech Connect

    Faust, R.L.

    1988-01-01

    In the present study, isolated epithelial sheets were obtained by performing two sequential anterior keratectomies, three weeks apart, on rabbit corneas. Light microscopy of the isolated sheets revealed a multilayered epithelium with an intact basal cell layer without contamination from other cell types. The accumulation of ({sup 3}H)choline into the epithelial sheets was studied at substrate concentrations varying from 1 to 100 {mu}Moles with and without the addition of specific metabolic and stereochemical inhibitors. Accumulation of ({sup 3}H)choline into these sheets was saturable. Kinetic analysis, performed by estimation from double-reciprocal plots, revealed a single component system with a K{sub m} of 24.9 {mu}M. The metabolic inhibitors potassium cyanide and ouabain showed no effect on the uptake of ({sup 3}H)choline; however, the stereochemical inhibitor hemicholinium-3 significantly reduced the accumulation of radiolabel at both high and low substrate concentrations. The results suggest a non-energy dependent yet a highly specific transport system for the accumulation of choline into the rabbit epithelium.

  20. 21 CFR 182.8250 - Choline bitartrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Choline bitartrate. 182.8250 Section 182.8250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8250 Choline bitartrate. (a) Product. Choline bitartrate....

  1. 21 CFR 182.8252 - Choline chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Choline chloride. 182.8252 Section 182.8252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8252 Choline chloride. (a) Product. Choline chloride....

  2. Improved human visuomotor performance and pupil constriction after choline supplementation in a placebo-controlled double-blind study

    PubMed Central

    Naber, Marnix; Hommel, Bernhard; Colzato, Lorenza S.

    2015-01-01

    Only few nutrients are known to enhance cognition. Here we explore whether visuomotor performance can be improved through the intake of the nutrient choline, an essential chemical compound in a vertebrate’s diet. Choline is abundant in for example eggs and shrimps and many animal studies suggest that it serves as a cognitive enhancer. As choline is important for the communication between motor neurons and the control of skeletal muscles, we assumed that choline supplementation may have positive effects on action coordination in humans. A group of twenty-eight individuals ingested two grams of choline bitartrate or a placebo in two separate sessions. Seventy minutes post ingestion, participants performed a visuomotor aiming task in which they had to rapidly hit the centers of targets. Results showed that participants hit targets more centrally after choline supplementation. Pupil size (a cognition-sensitive biomarker) also significantly decreased after choline intake and correlated positively with the hit distance to the targets and the number of target misses, and negatively with reaction times. These findings point to a choline-induced bias towards action precision in the trade-off between speed and accuracy. The changes in pupil size suggest that choline uptake alters cholinergic functions in the nervous system. PMID:26271904

  3. Improved human visuomotor performance and pupil constriction after choline supplementation in a placebo-controlled double-blind study.

    PubMed

    Naber, Marnix; Hommel, Bernhard; Colzato, Lorenza S

    2015-01-01

    Only few nutrients are known to enhance cognition. Here we explore whether visuomotor performance can be improved through the intake of the nutrient choline, an essential chemical compound in a vertebrate's diet. Choline is abundant in for example eggs and shrimps and many animal studies suggest that it serves as a cognitive enhancer. As choline is important for the communication between motor neurons and the control of skeletal muscles, we assumed that choline supplementation may have positive effects on action coordination in humans. A group of twenty-eight individuals ingested two grams of choline bitartrate or a placebo in two separate sessions. Seventy minutes post ingestion, participants performed a visuomotor aiming task in which they had to rapidly hit the centers of targets. Results showed that participants hit targets more centrally after choline supplementation. Pupil size (a cognition-sensitive biomarker) also significantly decreased after choline intake and correlated positively with the hit distance to the targets and the number of target misses, and negatively with reaction times. These findings point to a choline-induced bias towards action precision in the trade-off between speed and accuracy. The changes in pupil size suggest that choline uptake alters cholinergic functions in the nervous system. PMID:26271904

  4. Polyvalent choline phosphate as a universal biomembrane adhesive

    NASA Astrophysics Data System (ADS)

    Yu, Xifei; Liu, Zonghua; Janzen, Johan; Chafeeva, Irina; Horte, Sonja; Chen, Wei; Kainthan, Rajesh K.; Kizhakkedathu, Jayachandran N.; Brooks, Donald E.

    2012-05-01

    Phospholipids in the cell membranes of all eukaryotic cells contain phosphatidyl choline (PC) as the headgroup. Here we show that hyperbranched polyglycerols (HPGs) decorated with the ’PC-inverse’ choline phosphate (CP) in a polyvalent fashion can electrostatically bind to a variety of cell membranes and to PC-containing liposomes, the binding strength depending on the number density of CP groups per macromolecule. We also show that HPG-CPs can cause cells to adhere with varying affinity to other cells, and that binding can be reversed by subsequent exposure to low molecular weight HPGs carrying small numbers of PCs. Moreover, PC-rich membranes adsorb and rapidly internalize fluorescent HPG-CP but not HPG-PC molecules, which suggests that HPG-CPs could be used as drug-delivery agents. CP-decorated polymers should find broad use, for instance as tissue sealants and in the self-assembly of lipid nanostructures.

  5. Choline intake and genetic polymorphisms influence choline metabolite concentrations in human breast milk and plasma123

    PubMed Central

    Fischer, Leslie M; da Costa, Kerry Ann; Galanko, Joseph; Sha, Wei; Stephenson, Brigitte; Vick, Julie; Zeisel, Steven H

    2010-01-01

    Background: Choline is essential for infant nutrition, and breast milk is a rich source of this nutrient. Common single nucleotide polymorphisms (SNPs) change dietary requirements for choline intake. Objective: The aim of this study was to determine whether total choline intake and/or SNPs influence concentrations of choline and its metabolites in human breast milk and plasma. Design: We gave a total of 103 pregnant women supplemental choline or a placebo from 18 wk gestation to 45 d postpartum and genotyped the women for 370 common SNPs. At 45 d postpartum, we measured choline metabolite concentrations in breast milk and plasma and assessed the dietary intake of choline by using a 3-d food record. Results: On average, lactating women in our study ate two-thirds of the recommended intake for choline (Adequate Intake = 550 mg choline/d). Dietary choline intake (no supplement) correlated with breast-milk phosphatidylcholine and plasma choline concentrations. A supplement further increased breast-milk choline, betaine, and phosphocholine concentrations and increased plasma choline and betaine concentrations. We identified 5 SNPs in MTHFR that altered the slope of the intake–metabolite concentration relations, and we identified 2 SNPs in PEMT that shifted these curves upward. Individuals who shared sets of common SNPs were outliers in plots of intake–metabolite concentration curves; we suggest that these SNPs should be further investigated to determine how they alter choline metabolism. Conclusion: Total intake of choline and genotype can influence the concentrations of choline and its metabolites in the breast milk and blood of lactating women and thereby affect the amount of choline available to the developing infant. This study was registered at clinicaltrials.gov as NCT00678925. PMID:20534746

  6. Phosphatidylcholine and the CDP-Choline Cycle

    PubMed Central

    Fagone, Paolo; Jackowski, Suzanne

    2012-01-01

    The CDP-choline pathway of phosphatidylcholine (PtdCho) biosynthesis was first described more than 50 years ago. Investigation of the CDP-choline pathway in yeast provides a basis for understanding the CDP-choline pathway in mammals. PtdCho is considered as an intermediate in a cycle of synthesis and degradation, and the activity of a CDP-choline cycle is linked to subcellular membrane lipid movement. The components of the mammalian CDP-choline pathway include choline transport, choline kinase, phosphocholine cytidylyltransferase, and choline phosphotransferase activities. The protein isoforms and biochemical mechanisms of regulation of the pathway enzymes are related to their cell and tissue-specific functions. Regulated PtdCho turnover mediated by phospholipases or neuropathy target esterase participates in the mammalian CDP-choline cycle. Knockout mouse models define the biological functions of the CDP-choline cycle in mammalian cells and tissues. This article is part of a Special Issue entitled Phospholipids and Phospholipid Metabolism. PMID:23010477

  7. Choline Ions Stabilize A-T Base Pairs by Fitting into Minor Groove

    NASA Astrophysics Data System (ADS)

    Nakano, Miki; Tateishi-Karimata, Hisae; Tanaka, Shigenori; Sugimoto, Naoki

    In a Watson-Crick base paired DNA duplex, G-C base pairs are more stable than A-T base pairs. However, in solvent containing choline ions, the stabilities of these base pairs are reversed. To elucidate the mechanism through which choline ions exert this effect from a microscopic viewpoint, we performed molecular dynamics simulations. We found that choline ions interact with a DNA duplex through multiple hydrogen bonds. The affinity of choline ion for the minor groove of A-T base pairs was higher than that for the major groove. The binding of choline ions to the minor groove of A-T base pairs supports groove formation without disturbing the formation of hydrogen bonds between the base pairs. In contrast, choline ions inhibit the formation of hydrogen bonds between G-C base pairs by binding to atoms of these bases that are involved in Watson-Crick hydrogen bonding. These findings will help us understand the stabilities of canonical DNA structures under the crowded conditions inside cells.

  8. Purification and characterization of an alkaliphilic choline oxidase of Fusarium oxysporum.

    PubMed

    Enokibara, Shogo

    2012-01-01

    A novel choline oxidase found in a fungus, Fusarium oxysporum strain V2, was purified to homogeneity as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The enzyme has a molecular mass of 128 kDa and consists of two identical subunits. The purified enzyme showed adsorption peaks at 340 nm and 450 nm. It showed alkaliphilic pH characteristics: its optimum pH was 9.0-10.0, and it was stable at pH 8.0-10.2. The Michaelis constant (Km) values for choline and betaine aldehyde were 0.28 mM and 0.39 mM respectively. Trimethylamino-alcohols, dimethylamino-alcohols, and diethylaminoethanol were substrates for the enzyme, but the Km values for them increased with decreasing numbers of methyl groups on the ammonium headgroup. A marked decrease in the maximum velocity (Vmax) and Vmax/Km values was observed when N-replaced choline analogs were used as substrate instead of choline. The enzyme had a remarkably higher affinity for choline and betaine aldehyde than do previously reported enzymes. The enzyme oxidized these two substrates more quickly than a choline oxidase from Arthrobacter globiformis, and oxidation by the V2 enzyme was accompanied by an increase in the stoichometric amount of hydrogen peroxide. PMID:23221722

  9. OsPHF1 Regulates the Plasma Membrane Localization of Low- and High-Affinity Inorganic Phosphate Transporters and Determines Inorganic Phosphate Uptake and Translocation in Rice1[W][OA

    PubMed Central

    Chen, Jieyu; Liu, Yu; Ni, Jun; Wang, Yifeng; Bai, Youhuang; Shi, Jing; Gan, Jian; Wu, Zhongchang; Wu, Ping

    2011-01-01

    PHOSPHATE TRANSPORTER TRAFFIC FACILITATOR1 (PHF1) is known to regulate the plasma membrane localization of PHT1;1, a high-affinity inorganic phosphate (Pi) transporter in Arabidopsis (Arabidopsis thaliana). OsPHF1, a rice (Oryza sativa) gene homologous to AtPHF1, was isolated and found to regulate the localization of both low- and high-affinity Pi transporters to the plasma membrane. Three OsPHF1 allelic mutants carrying one-point mutations at the fifth WD-repeat motif and two at the transmembrane helix, respectively, showed arsenate resistance and severely reduced Pi accumulation. The data indicate that mutation of OsPHF1 results in the endoplasmic reticulum retention of the low-affinity Pi transporter OsPT2 and high-affinity Pi transporter OsPT8. Mutation of OsPHF1 also reduced Pi accumulation in plants exhibiting excessive shoot Pi accumulation due to the overexpression of OsPHR2. However, the transcript level of OsPHF1 itself is not controlled by OsPHR2. Overexpression of OsPHF1 increased Pi accumulation in both roots and shoots in a solution culture with Pi-supplied condition. These results indicate that the role of OsPHF1 is unique in the localization of both low- and high-affinity Pi transporters on the plasma membrane in rice and determines Pi uptake and translocation in rice. The similar function of PHF1 required to facilitate PHT1 transit through the endoplasmic reticulum between Arabidopsis and rice provides an example of expectations from what one would deduce from sequence comparisons to extend knowledge from Arabidopsis to crops. PMID:21753117

  10. Is choline PET useful for identifying intraprostatic tumour lesions? A literature review.

    PubMed

    Chan, Joachim; Syndikus, Isabel; Mahmood, Shelan; Bell, Lynn; Vinjamuri, Sobhan

    2015-09-01

    More than 80% of patients with intermediate-risk or high-risk localized prostate cancer are cured with radiation doses of 74-78 Gy, but high doses increase the risk for late bowel and bladder toxicity among long-term survivors. Dose painting, defined as dose escalation to areas in the prostate containing the tumour, rather than to the whole gland, minimizes dose to normal tissues and hence toxicity. It requires accurate identification of the location and size of these lesions, for which functional MRI is the current gold standard. Many studies have assessed the use of choline PET in staging newly diagnosed patients. This review will discuss important imaging variables affecting the accuracy of choline PET scans, how choline PET contributes to tumour identification and is used in radiotherapy planning and how PET can improve the patient pathway involving prostate radiotherapy. In summary, the available literature shows that the accuracy of choline PET improves with higher tracer doses and delayed imaging (although the optimal uptake time is unclear), and tumour identification by MRI is improved by the addition of PET imaging. We propose future research with prolonged choline uptake time and multiphase imaging, which may further improve accuracy. PMID:25955523

  11. 11C-Choline and FDG PET/CT Imaging of Primary Cholangiocarcinoma: A Comparative Analysis

    PubMed Central

    Chotipanich, Chanisa; Promteangtrong, Chetsadaporn; Kunawudhi, Anchisa; Chanwat, Rawisak; Sricharunrat, Thaniya; Suratako, Savitree; Wongsa, Paramest

    2015-01-01

    Objective(s): This study aimed to compare the diagnostic values of 11C-choline and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in patients with cholangiocarcinoma (CCA). Methods: This prospective study was conducted on 10 patients (6 males and 4 females), aged 42-69 years, suspected of having CCA based on CT or magnetic resonance imaging (MRI) results. 11C-choline and 18F-FDG PET/CT studies were performed in all patients over 1 week. PET/CT results were visually analyzed by 2 independent nuclear medicine physicians and quantitatively by calculating the tumor-to-background ratio (T/B). Results: No 11C-choline PET/CT uptake was observed in primary extrahepatic or intrahepatic CCA cases. Intense 18F-FDG avidity was detected in the tumors of 8 patients (%80). Two patients, who were 18F-FDG negative, had primary extrahepatic CCA. Ki-67 measurements were positive in all patients (range; 14.2%-39.9%). The average T/B values of 11C-choline and 18F-FDG were 0.4±0.2 and 2.0±1.0 in all cases of primary CCA, respectively; these values were significantly lower for 11C-choline (P<0.005). Both FDG and 11C-choline PET/CT detected metastatic CCA foci in all 8 patients (two patients had no metastases). Conclusion: As the results suggested, primary CCA lesions showed a poor avidity for 11C-choline, whereas 18F-FDG PET/CT was of value for the detection of most primary CCA cases. In contrast to primary lesions, metastatic CCA lesions showed 11C-choline avidity.

  12. Characterization of the high affinity Zn transporter from Noccaea caerulescens, NcZNT1, and dissection of its promoter for its role in Zn uptake and hyperaccumulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this paper, we conducted a detailed analysis of the ZIP family transporter, NcZNT1, in the Zn/Cd hyperaccumulating plant species, Noccaea caerulescens, formerly known as Thlaspi caerulescens. NcZNT1 was previously suggested to be the primary root Zn/Cd uptake transporter. Both a characterization ...

  13. [18F]Fluoromethyl-[1,2-2H4]-choline: A novel radiotracer for imaging choline metabolism in tumors by positron emission tomography

    PubMed Central

    Leyton, Julius; Smith, Graham; Zhao, Yongjun; Perumal, Meg; Nguyen, Quang-De; Robins, Edward; Årstad, Erik; Aboagye, Eric O.

    2009-01-01

    Current radiotracers for positron emission tomography (PET) imaging of choline metabolism have poor systemic metabolic stability in vivo. We describe a novel radiotracer, [18F]fluoromethyl-[1,2-2H4]-choline (D4-FCH), that employs deuterium isotope effect to improve metabolic stability. D4-FCH proved more resistant to oxidation than its non-deuterated analog, [18F]fluoromethylcholine (FCH), in plasma, kidneys, liver and tumor, while retaining phosphorylation potential. Tumor radiotracer levels, a determinant of sensitivity in imaging studies, was improved by deuterium substitution; tumor uptake values expressed as %injected dose/voxel at 60 min were 7.43 ± 0.47 and 5.50 ± 0.49 for D4-FCH and FCH, respectively, (P = 0.04). D4-FCH was also found to be a useful response biomarker. Treatment with the mitogenic extracellular kinase inhibitor, PD0325901, resulted in a reduction in tumor radiotracer uptake that occurred in parallel with reductions in choline kinase A expression. In conclusion, D4-FCH is a very promising metabolically stable radiotracer for imaging choline metabolism in tumors. PMID:19773436

  14. 21 CFR 582.5250 - Choline bitartrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Choline bitartrate. 582.5250 Section 582.5250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements 1 § 582.5250 Choline bitartrate....

  15. 21 CFR 582.5252 - Choline chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Choline chloride. 582.5252 Section 582.5252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements 1 § 582.5252 Choline chloride....

  16. Centrifuge-induced hypergravity: [ 3H]GABA and L-[ 14C]glutamate uptake, exocytosis and efflux mediated by high-affinity, sodium-dependent transporters

    NASA Astrophysics Data System (ADS)

    Borisova, T. A.; Himmelreich, N. H.

    The effects of centrifuge-induced hypergravity on the presynaptic events have been investigated in order to provide further insight into regulation of glutamate and GABA neurotransmission and correlation between excitatory and inhibitory responses under artificial gravity conditions. Exposure of animals to hypergravity (centrifugation of rats at 10 G for 1 h) has been found to cause changes in the synaptic processes of brain, in particular neurotransmitter release and uptake in rat brain synaptosomes. Hypergravity loading resulted in more than two-fold enhancement of GABA transporter activity ( Vmax increased from 1.4 ± 0.3 nmol/min/mg of protein in the control group to 3.3 ± 0.59 nmol/min/mg of protein for the animals exposed to hypergravity ( P ⩽ 0.05)). The maximal velocity of L-[ 14C]glutamate uptake decreased from 12.5 ± 3.2 to 5.6 ± 0.9 nmol/min/mg of protein under artificial gravity conditions. Depolarization-evoked exocytotic release of the neurotransmitters has also changed in response to hypergravity. It increased for GABA (7.2 ± 0.54% and 11.74 ± 1.2% of total accumulated label for control and hypergravity, respectively ( P ⩽ 0.05)), but reduced for glutamate (14.4 ± 0.7% and 6.2 ± 1.9%, for control and hypergravity, respectively). Thus, comparative analysis of the neurotransmitter uptake and release has demonstrated that short-term centrifuge-induced 10 G hypergravity loading intensified inhibitory and attenuated excitatory processes in nerve terminals. The activation or reduction of neurotransmitter uptake appeared to be coupled with similarly directed alterations of the neurotransmitter release.

  17. An improved choline monooxygenase assay

    SciTech Connect

    Lafontaine, P.J.; Hanson, A.D. )

    1991-05-01

    Glycine betaine accumulates in leaves of plants from several angiosperm families in response to drought or salinization. Its synthesis, from the oxidation of choline, is mediated by a two step pathway. In spinach the first enzyme of this pathway is a ferredoxin-dependent choline monooxygenase (CMO). In order to purify this enzyme a sensitive and reliable assay is necessary. Two types of modifications were explored to improve the existing assay. (1) Ferredoxin reduction - one way of providing reduced Fd to CMO is by the addition of isolated spinach thylakoids in the assay mixture. In order to optimize the reduction of Fd two different systems were compared: (a) where only PS is active, by adding DCMU to inhibit electron transport from PS II and DAD as electron donor for PS I; (b) where both PS II and PS I are active. (2) Betaine aldehyde estimation - to simplify this, it is possible to couple the CMO reaction with betaine aldehyde dehydrogenase (BADH) from E. coli. BADH converts betaine aldehyde to betaine as it is formed in the assay, eliminating the need for a chemical oxidation step.

  18. Identification of an osmo-dependent and an osmo-independent choline transporter in Acinetobacter baylyi: implications in osmostress protection and metabolic adaptation.

    PubMed

    Sand, Miriam; Stahl, Julia; Waclawska, Izabela; Ziegler, Christine; Averhoff, Beate

    2014-06-01

    Members of the genus Acinetobacter are well known for their metabolic versatility that allows them to adapt to different ecological niches. In previous studies, we have demonstrated that Acinetobacter baylyi ADP1 can cope with high salinities by uptake and accumulation of the well-known compatible solute glycine betaine. Here, we demonstrate that addition of choline restores growth at high salinities. We further show that choline was actively taken up by the cells and converted to glycine betaine. Uptake of choline was induced by high salinity and the presence of choline in the growth medium. At high salinities, glycine betaine was accumulated in the cells whereas in the absence of osmotic stress it was exported. Inspection of the genome sequence followed by mutant studies led to the identification of two genes encoding secondary transporters (BetT1 and BetT2) of the betaine-choline-carnitine transporter (BCCT) family. The BetT1 transporter lacks an extended C-terminal domain usually found in osmoregulated choline BCCTs. BetT1 was found to facilitate osmolarity-independent choline transport most likely by a uniport mechanism. We propose that BetT1 does not primarily function in osmoadaptation but might play a role in metabolic adaptation to choline-rich environments. PMID:23889709

  19. Affinity Chromatography.

    ERIC Educational Resources Information Center

    Gray, Gary R.

    1980-01-01

    Presents selected recent advances in immobilization chemistry which have important connections to affinity chromatography. Discusses ligand immobilization and support modification. Cites 51 references. (CS)

  20. Choline transport in Leishmania major promastigotes and its inhibition by choline and phosphocholine analogs.

    PubMed

    Zufferey, Rachel; Mamoun, Choukri Ben

    2002-01-01

    Phosphatidylcholine is the most abundant phospholipid in the membranes of the human parasite Leishmania. The metabolic pathways leading to its biosynthesis are likely to play a critical role in parasite development and survival and may offer a good target for antileishmanial chemotherapy. Phosphatidylcholine synthesis via the CDP-choline pathway requires transport of the choline precursor from the host. Here, we report the first characterization of choline transport in this parasite, which is carrier-mediated and exhibits Michaelis-Menten kinetics with an apparent K(m) value of 2.5 microM for choline. This process is Na(+)-independent and requires an intact proton gradient to be fully functional. Choline transport into Leishmania is highly specific for choline and is inhibited by the choline carrier inhibitor hemicholinium-3, the channel blocker quinacrine, the antimalarial aminoquinolines quinine and quinidine, the antileishmanial phosphocholine analogs, miltefosine and edelfosine, and by choline analogs, most of which have antimalarial activities. Most importantly, choline analogs kill the promastigote form of the parasite in vitro in the low micromolar range. These results set the stage for the use of choline analogs in antileishmanial chemotherapy and shed new lights on the mechanism of action of the leishmanicidal phosphocholine analogs. PMID:12467980

  1. Choline intakes exceeding recommendations during human lactation improve breast milk choline content by increasing PEMT pathway metabolites.

    PubMed

    Davenport, Crystal; Yan, Jian; Taesuwan, Siraphat; Shields, Kelsey; West, Allyson A; Jiang, Xinyin; Perry, Cydne A; Malysheva, Olga V; Stabler, Sally P; Allen, Robert H; Caudill, Marie A

    2015-09-01

    Demand for the vital nutrient choline is high during lactation; however, few studies have examined choline metabolism and requirements in this reproductive state. The present study sought to discern the effects of lactation and varied choline intake on maternal biomarkers of choline metabolism and breast milk choline content. Lactating (n=28) and control (n=21) women were randomized to 480 or 930 mg choline/day for 10-12 weeks as part of a controlled feeding study. During the last 4-6 weeks, 20% of the total choline intake was provided as an isotopically labeled choline tracer (methyl-d9-choline). Blood, urine and breast milk samples were collected for choline metabolite quantification, enrichment measurements, and gene expression analysis of choline metabolic genes. Lactating (vs. control) women exhibited higher (P < .001) plasma choline concentrations but lower (P ≤ .002) urinary excretion of choline metabolites, decreased use of choline as a methyl donor (e.g., lower enrichment of d6-dimethylglycine, P ≤ .08) and lower (P ≤ .02) leukocyte expression of most choline-metabolizing genes. A higher choline intake during lactation differentially influenced breast milk d9- vs. d3-choline metabolite enrichment. Increases (P ≤ .03) were detected among the d3-metabolites, which are generated endogenously via the hepatic phosphatidylethanolamine N-methyltransferase (PEMT), but not among the d9-metabolites generated from intact exogenous choline. These data suggest that lactation induces metabolic adaptations that increase the supply of intact choline to the mammary epithelium, and that extra maternal choline enhances breast milk choline content by increasing supply of PEMT-derived choline metabolites. This trial was registered at clinicaltrials.gov as NCT01127022. PMID:26025328

  2. Pivotal role of choline metabolites in remyelination.

    PubMed

    Skripuletz, Thomas; Manzel, Arndt; Gropengießer, Karoline; Schäfer, Nora; Gudi, Viktoria; Singh, Vikramjeet; Salinas Tejedor, Laura; Jörg, Stefanie; Hammer, Anna; Voss, Elke; Vulinovic, Franca; Degen, Diane; Wolf, Rebecca; Lee, De-Hyung; Pul, Refik; Moharregh-Khiabani, Darius; Baumgärtner, Wolfgang; Gold, Ralf; Linker, Ralf A; Stangel, Martin

    2015-02-01

    Neuroprotective approaches for central nervous system regeneration have not been successful in clinical practice so far and compounds that enhance remyelination are still not available for patients with multiple sclerosis. The objective of this study was to determine potential regenerative effects of the substance cytidine-5'-diphospho (CDP)-choline in two different murine animal models of multiple sclerosis. The effects of exogenously applied CDP-choline were tested in murine myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis. In addition, the cuprizone-induced mouse model of de- and remyelination was used to specifically test the hypothesis that CDP-choline directly increases remyelination. We found that CDP-choline ameliorated the disease course of experimental autoimmune encephalomyelitis and exerted beneficial effects on myelin, oligodendrocytes and axons. After cuprizone-induced demyelination, CDP-choline effectively enhanced myelin regeneration and reversed motor coordination deficits. The increased remyelination arose from an increase in the numbers of proliferating oligodendrocyte precursor cells and oligodendrocytes. Further in vitro studies suggest that this process is regulated by protein kinase C. We thus identified a new mechanism to enhance central nervous system remyelination via the choline pathway. Due to its regenerative action combined with an excellent safety profile, CDP-choline could become a promising substance for patients with multiple sclerosis as an add-on therapy. PMID:25524711

  3. The effect of preganglionic nerve stimulation on the accumulation of certain analogues of choline by a sympathetic ganglion.

    PubMed Central

    Collier, B; Ilson, D

    1977-01-01

    1. Cat superior cervical ganglia were perfused with a Krebs solution containing 10(-6) M [3H]homocholine (2-hydroxypropyl-trimethylammonium) or 10(-5) M [14C]triethylcholine (2-hydroxyethyl-triethylammonium). Preganglionic nerve stimulation (20 Hz) increased the accumulation of homocholine (3-2-fold) and of triethylcholine (2-1-fold). This increased accumulation during stimulation was not the result of increased metabolism. 2. The increased accumulation of homocholine or triethylcholine induced by pregnaglionic nerve stimulation was not reduced by tubocurarine or by atropine, but it was blocked by choline and by hemicholinium. These results suggested that preganglionic nerve stimulation increased choline analogue accumulation into cholinergic nerve terminals. 3. The increased accumulation of homocholine or of triethylcholine induced by preganglionic nerve stimulation was reduced when the Ca2+ concentration was reduced and was abolished in the absence of Ca2+. However, changes in the Mg2+ concentration which depressed acetylcholine (ACh) release by amounts comparable to those induced by altered Ca2+ concentrations did not alter the uptake of homocholine or triethylcholine. It is concluded that the uptake of choline analogues is not regulated by transmitter release but that stimulation increases the uptake of the choline analogues by a Ca2+-dependent mechanism. 4. The accumulation of ACh by ganglia perfused with a Krebs solution containing choline and high MgSO4 (18 mM) was measured. The ACh content of these ganglia did not increase, although choline transport presumably exceeded that necessary for ACh synthesis to replace released ACh. It is concluded that choline transport does not limit ACh synthesis in ganglia. PMID:839464

  4. Prenatal choline and the development of schizophrenia

    PubMed Central

    FREEDMAN, Robert; ROSS, Randal G.

    2015-01-01

    Background The primary prevention of illness at the population level, the ultimate aim of medicine, seems out of reach for schizophrenia. Schizophrenia has a strong genetic component, and its pathogenesis begins long before the emergence of psychosis, as early as fetal brain development. Cholinergic neurotransmission at nicotinic receptors is a pathophysiological mechanism related to one aspect of this genetic risk. Choline activates these nicotinic receptors during fetal brain development. Dietary supplementation of maternal choline thus emerges as a possible intervention in pregnancy to alter the earliest developmental course of the illness. Aim Review available literature on the relationship of choline supplementation or choline levels during pregnancy and fetal brain development. Methods A Medline search was used to identify studies assessing effects of choline in human fetal development. Studies of other prenatal risk factors for schizophrenia and the role of cholinergic neurotransmission in its pathophysiology were also identified. Results Dietary requirements for choline are high during pregnancy because of its several uses, including membrane biosynthesis, one-carbon metabolism, and cholinergic neurotransmission. Its ability to act directly at high concentrations as a nicotinic agonist is critical for normal brain circuit development. Dietary supplementation in the second and third trimesters with phosphatidyl-choline supports these functions and is associated generally with better fetal outcome. Improvement in inhibitory neuronal functions whose deficit is associated with schizophrenia and attention deficit disorder has been observed. Conclusion Prenatal dietary supplementation with phosphatidyl-choline and promotion of diets rich in choline-containing foods (meats, soybeans, and eggs) are possible interventions to promote fetal brain development and thereby decrease the risk of subsequent mental illnesses. The low risk and short (sixmonth) duration of the

  5. Choline-containing lipids in mycoplasmas.

    PubMed

    Rottem, Shlomo

    2002-07-01

    Choline-containing lipids were identified and characterized in the cell membrane of Mycoplasma fermentans and were shown to participate in the adhesion to the surface of eukaryotic cells, to stimulate mycoplasma fusion with eukaryotic cells, and to induce cytokine secretion by cells of the immune system. These findings suggest that choline-containing lipids are important mediators of tissue pathology in the infectious process caused by M. fermentans. PMID:12106789

  6. Deanol affects choline metabolism in peripheral tissues of mice.

    PubMed

    Haubrich, D R; Gerber, N H; Pflueger, A B

    1981-08-01

    Administration of 2-dimethylaminoethanol (deanol) to mice induced an increase in both the concentration and the rate of turnover of free choline in blood. Treatment with deanol also caused an increase in the concentration of choline in kidneys, and markedly inhibited the rates of oxidation and phosphorylation of intravenously administered [3H-methyl]choline. In the liver, deanol inhibited the rate of phosphorylation of [3H-methyl]choline, but did not inhibit its rate of oxidation or cause an increase in the level of free choline. These findings suggest that deanol increases the choline concentration in blood by inhibition of its metabolism in tissues. Deanol may ultimately produce its central cholinergic effects by inhibition of choline metabolism in peripheral tissues, causing free choline choline to accumulate in blood, enter the brain, and stimulate cholinergic receptors. PMID:7264671

  7. Choline incorporation by Schistosoma mansoni: distribution of choline metabolites during development and after sexual differentiation

    SciTech Connect

    Ancelin, M.L.; Torpier, G.; Vial, H.J.; Capron, A.

    1987-06-01

    Choline metabolism was investigated in Schistosoma mansoni during the main phases of its development, namely, schistosomula, 11- and 15-day-old worms, and adults. At the physiological choline concentration used in the assay (20 microM), betaine was, along with phosphatidylcholine, one of the most abundant choline metabolites, revealing considerable choline oxidation activity. Very little radioactivity was associated with CDP-choline, whereas a sustained incorporation into phosphocholine occurred. These results provide good evidence that CTP:phosphocholine cytidylyltransferase plays a regulatory role in the de novo pathway of phosphatidylcholine biosynthesis. During development, the incorporation of choline into its various metabolites was maximal in 11-day-old worms. At this stage, the oxidative pathway predominated over the Kennedy pathway, whereas at all other stages the de novo phosphatidylcholine biosynthesis was predominant. Furthermore, choline incorporation into betaine was much more important in the adult female worm than in the male, indicating a major difference in choline incorporation and distribution between the 2 sexes of the adult worms.

  8. The effect of cytidine-diphosphate choline (CDP-choline) on brain lipid changes during aging

    SciTech Connect

    De Medio, G.E.; Trovarelli, G.; Piccinin, G.L.; Porcellati, G.

    1984-01-01

    Lipid synthesis has been tested in vivo in different brain areas of 12-month-old male rats. Cortex, striatum, brainstem, and subcortex of brain have been examined. The cerebellum was discarded. Mixtures of (2-/sup 3/H)glycerol and (Me-/sup 14/C)choline were injected into the lateral ventricle of the brain as lipid precursors, and their incorporation into total lipid, water-soluble intermediates and choline-containing phospholipids was examined 1 hr after isotope injection. In another series of experiments cytidine-5'-diphosphate choline (CDP-choline) was injected intraventricularly to the aged rats 10 min before sacrifice with a simultaneous injection, and radioactivity assays were performed as above. Distribution of radioactivity content of CDP-choline among brain areas 10 min after its administration showed a noticeable enrichment of the nucleotide and water-soluble-related compounds in the examined areas, but to a lesser degree in the cerebral cortex. The incorporation of labelled glycerol, which is severely depressed in aged rats in all four areas (Gaiti et al, 1982, 1983), was increased only in the cortex, and apparently decreased in the other areas. This last result is probably due to a dilution effect brought about by the administered cold CDP-choline upon the (/sup 14/C)-containing water-soluble metabolites. As a consequence, the (/sup 3/H)/(/sup 14/C) ratio in total lipid and in isolated phosphatidylcholine and choline plasmalogen increased after CDP-choline treatment.

  9. Dietary Intake of Choline and Plasma Choline Concentrations in Pregnant Women in Jamaica

    PubMed Central

    Gossell-Williams, M; Fletcher, H; McFarlane-Anderson, N; Jacob, A; Patel, J; Zeisel, S

    2008-01-01

    Choline is an essential nutrient for humans and its availability during pregnancy is important for optimal fetal development. The Food and Nutrition Board of the Institute of Medicine in the United States of America has set the adequate choline intake during pregnancy at 450 mg/day. There is limited data available on normal plasma choline concentrations in pregnancy. Moreover, there are neither documented studies of choline intake among pregnant women in the Jamaican population nor of free plasma choline concentrations during pregnancy. Sixteen women presenting to the antenatal clinic of the University Hospital of the West Indies (UHWI) at 10−15 weeks of gestation were selected for this pilot study. A food frequency questionnaire was administered to estimate frequency of consumption of foods rich in choline. Fasting blood samples were collected by venepuncture and plasma assayed for choline using liquid chromatography electrospray ionization isotopic dilution mass spectrometry. Most of the women reported consumption of diets that delivered less than the recommended choline intake (mean ± SEM, 278.5 ± 28.9 mg). Mean plasma choline concentration was 8.4 ± 0.4 μmol/L. This falls below the normal concentration (10 μmol/L) reported for individuals that are not pregnant and pregnant (14.5 μmol/L). The results of this study may be an indication that the choline included in the diet of pregnant women in Jamaica may not be adequate to meet both the needs of the mother and fetus and that further studies are warranted to determine clinical implications. PMID:16642650

  10. 18F-Choline PET/CT-Positive Lytic Bone Lesions in Prostate Cancer and Accidental Myeloma Detection.

    PubMed

    Florimonte, Luigia; Orunesu, Eva; Castellani, Massimo; Longari, Virgilio; Cortelezzi, Agostino

    2016-05-01

    F-choline PET/CT was performed for suspected prostate cancer relapse in a 67-year-old man with hip pain and a rapid rise in prostate-specific antigen values (1.1 ng/mL). PET imaging showed an area of increased F-choline bone uptake in the right ischium. Coregistered CT images showed a lytic bone lesion. The infrequent CT appearance of a possible prostate carcinoma metastasis led to additional laboratory testing that showed a monoclonal γ-peak and to subsequent biopsy, which revealed a solitary plasmocytoma. PMID:26825195

  11. Early increase in phosphatidyl choline synthesis by choline and transmethylation pathways in spreading fibroblasts

    SciTech Connect

    Maziere, C.; Maziere, J.C.; Mora, L.; Polonovski, J.

    1986-11-01

    Phosphatidyl choline (PC) synthesis in trypsinized and reattaching fibroblasts during the spreading state was studied by incorporation of (/sup 14/C)choline and (methyl-/sup 14/C)methionine. The choline and phosphatidyl-ethanolamine (PE) transmethylation pathways were both transiently increased about 2-fold during the first 2 h after replating. Maximum increase appeared to be simultaneous with maximum spreading. Incorporation of (/sup 32/P)orthophosphate showed that the increase in PC synthesis was specific and most probably related to establishment of cell-substrate adhesion sites.

  12. Role of H{sub 2}O{sub 2} on the kinetics of low-affinity high-capacity Na{sup +}-dependent alanine transport in SHR proximal tubular epithelial cells

    SciTech Connect

    Pinto, Vanda; Pinho, Maria Joao; Jose, Pedro A.; Soares-da-Silva, Patricio

    2010-07-30

    Research highlights: {yields} H{sub 2}O{sub 2} in excess is required for the presence of a low-affinity high-capacity component for the Na{sup +}-dependent [{sup 14}C]-L-alanine uptake in SHR PTE cells only. {yields} It is suggested that Na{sup +} binding in renal ASCT2 may be regulated by ROS in SHR PTE cells. -- Abstract: The presence of high and low sodium affinity states for the Na{sup +}-dependent [{sup 14}C]-L-alanine uptake in immortalized renal proximal tubular epithelial (PTE) cells was previously reported (Am. J. Physiol. 293 (2007) R538-R547). This study evaluated the role of H{sub 2}O{sub 2} on the Na{sup +}-dependent [{sup 14}C]-L-alanine uptake of ASCT2 in immortalized renal PTE cells from Wistar Kyoto rat (WKY) and spontaneously hypertensive rat (SHR). Na{sup +} dependence of [{sup 14}C]-L-alanine uptake was investigated replacing NaCl with an equimolar concentration of choline chloride in vehicle- and apocynin-treated cells. Na{sup +} removal from the uptake solution abolished transport activity in both WKY and SHR PTE cells. Decreases in H{sub 2}O{sub 2} levels in the extracellular medium significantly reduced Na{sup +}-K{sub m} and V{sub max} values of the low-affinity high-capacity component in SHR PTE cells, with no effect on the high-affinity low-capacity state of the Na{sup +}-dependent [{sup 14}C]-L-alanine uptake. After removal of apocynin from the culture medium, H{sub 2}O{sub 2} levels returned to basal values within 1 to 3 h in both WKY and SHR PTE cells and these were found stable for the next 24 h. Under these experimental conditions, the Na{sup +}-K{sub m} and V{sub max} of the high-affinity low-capacity state were unaffected and the low-affinity high-capacity component remained significantly decreased 1 day but not 4 days after apocynin removal. In conclusion, H{sub 2}O{sub 2} in excess is required for the presence of a low-affinity high-capacity component for the Na{sup +}-dependent [{sup 14}C]-L-alanine uptake in SHR PTE cells only

  13. 21 CFR 573.580 - Iron-choline citrate complex.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Iron-choline citrate complex. 573.580 Section 573... Food Additive Listing § 573.580 Iron-choline citrate complex. Iron-choline citrate complex made by... used as a source of iron in animal feed....

  14. 21 CFR 172.370 - Iron-choline citrate complex.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Iron-choline citrate complex. 172.370 Section 172... CONSUMPTION Special Dietary and Nutritional Additives § 172.370 Iron-choline citrate complex. Iron-choline... citric acid may be safely used as a source of iron in foods for special dietary use....

  15. 21 CFR 172.370 - Iron-choline citrate complex.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Iron-choline citrate complex. 172.370 Section 172... Nutritional Additives § 172.370 Iron-choline citrate complex. Iron-choline citrate complex made by reacting... source of iron in foods for special dietary use....

  16. 21 CFR 172.370 - Iron-choline citrate complex.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Iron-choline citrate complex. 172.370 Section 172... CONSUMPTION Special Dietary and Nutritional Additives § 172.370 Iron-choline citrate complex. Iron-choline... citric acid may be safely used as a source of iron in foods for special dietary use....

  17. 21 CFR 573.580 - Iron-choline citrate complex.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Iron-choline citrate complex. 573.580 Section 573... Food Additive Listing § 573.580 Iron-choline citrate complex. Iron-choline citrate complex made by... used as a source of iron in animal feed....

  18. 21 CFR 573.580 - Iron-choline citrate complex.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Iron-choline citrate complex. 573.580 Section 573... Food Additive Listing § 573.580 Iron-choline citrate complex. Iron-choline citrate complex made by... used as a source of iron in animal feed....

  19. 21 CFR 172.370 - Iron-choline citrate complex.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Iron-choline citrate complex. 172.370 Section 172... CONSUMPTION Special Dietary and Nutritional Additives § 172.370 Iron-choline citrate complex. Iron-choline... citric acid may be safely used as a source of iron in foods for special dietary use....

  20. 21 CFR 172.370 - Iron-choline citrate complex.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Iron-choline citrate complex. 172.370 Section 172... CONSUMPTION Special Dietary and Nutritional Additives § 172.370 Iron-choline citrate complex. Iron-choline... citric acid may be safely used as a source of iron in foods for special dietary use....

  1. 21 CFR 573.580 - Iron-choline citrate complex.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Iron-choline citrate complex. 573.580 Section 573... Food Additive Listing § 573.580 Iron-choline citrate complex. Iron-choline citrate complex made by... used as a source of iron in animal feed....

  2. 21 CFR 573.580 - Iron-choline citrate complex.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Iron-choline citrate complex. 573.580 Section 573... Food Additive Listing § 573.580 Iron-choline citrate complex. Iron-choline citrate complex made by... used as a source of iron in animal feed....

  3. 21 CFR 573.300 - Choline xanthate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Choline xanthate. 573.300 Section 573.300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food...

  4. 21 CFR 573.300 - Choline xanthate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Choline xanthate. 573.300 Section 573.300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food...

  5. 21 CFR 582.5252 - Choline chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Choline chloride. 582.5252 Section 582.5252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  6. 21 CFR 582.5250 - Choline bitartrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Choline bitartrate. 582.5250 Section 582.5250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  7. 21 CFR 582.5250 - Choline bitartrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Choline bitartrate. 582.5250 Section 582.5250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  8. 21 CFR 582.5252 - Choline chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Choline chloride. 582.5252 Section 582.5252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  9. 21 CFR 182.8252 - Choline chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Choline chloride. 182.8252 Section 182.8252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8252...

  10. 21 CFR 182.8252 - Choline chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Choline chloride. 182.8252 Section 182.8252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8252...

  11. 21 CFR 182.8250 - Choline bitartrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Choline bitartrate. 182.8250 Section 182.8250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8250...

  12. 21 CFR 582.5250 - Choline bitartrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Choline bitartrate. 582.5250 Section 582.5250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  13. 21 CFR 182.8250 - Choline bitartrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Choline bitartrate. 182.8250 Section 182.8250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8250...

  14. 21 CFR 182.8250 - Choline bitartrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Choline bitartrate. 182.8250 Section 182.8250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8250...

  15. 21 CFR 582.5252 - Choline chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Choline chloride. 582.5252 Section 582.5252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  16. 21 CFR 182.8252 - Choline chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Choline chloride. 182.8252 Section 182.8252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8252...

  17. 21 CFR 582.5250 - Choline bitartrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Choline bitartrate. 582.5250 Section 582.5250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  18. 21 CFR 582.5252 - Choline chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Choline chloride. 582.5252 Section 582.5252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or...

  19. 21 CFR 182.8250 - Choline bitartrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Choline bitartrate. 182.8250 Section 182.8250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8250...

  20. 21 CFR 182.8252 - Choline chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Choline chloride. 182.8252 Section 182.8252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8252...

  1. USDA Choline Data for Baby Food

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Choline, a dietary component occurring naturally in high-protein and high-fat foods (e.g., eggs, meat, fish, nuts, legumes and human milk), plays a critical role in normal brain development (Zeisel et. al, 2004). It is essential to the development of cell membranes and therefore, inadequate intake b...

  2. Novel choline esterase based sensor for monitoring of organophosphorus pollutants

    SciTech Connect

    Wilkins, E.S.; Ghindilis, A.L.; Atanasov, P.

    1996-12-31

    Organophosphorus compounds are significant major environmental pollutants due to their intensive use as pesticides. The modern techniques based on inhibition of choline esterase enzyme activity are discussed. Potentiometric electrodes based on detection of choline esterase inhibition by analytes has been developed. The detection of choline esterase activity is based on the novel principle of molecular transduction. Immobilized peroxidase acting as the molecular transducer, catalyzes the electroreduction of hydrogen peroxide by direct (mediatorless) electron transfer. The sensing element consists of a carbon based electrode containing an assembly of co-immobilized enzymes: choline esterase, choline oxidase and peroxidase.

  3. Choline metabolism-based molecular diagnosis of cancer: an update

    PubMed Central

    Glunde, Kristine; Penet, Marie-France; Jiang, Lu; Jacobs, Michael A; Bhujwalla, Zaver M

    2016-01-01

    Abnormal choline metabolism continues to be identified in multiple cancers. Molecular causes of abnormal choline metabolism are changes in choline kinase-α, ethanolamine kinase-α, phosphatidylcholine-specific phospholipase C and -D and glycerophosphocholine phosphodiesterases, as well as several choline transporters. The net outcome of these enzymatic changes is an increase in phosphocholine and total choline (tCho) and, in some cancers, a relative decrease of glycerophosphocholine. The increased tCho signal detected by 1H magnetic resonance spectroscopy is being evaluated as a diagnostic marker in multiple cancers. Increased expression and activity of choline transporters and choline kinase-α have spurred the development of radiolabeled choline analogs as PET imaging tracers. Both tCho 1H magnetic resonance spectroscopy and choline PET are being investigated to detect response to treatment. Enzymes mediating the abnormal choline metabolism are being explored as targets for cancer therapy. This review highlights recent molecular, therapeutic and clinical advances in choline metabolism in cancer. PMID:25921026

  4. Choline oxidation by intact spinach chloroplasts. [Spinacia oleracea L

    SciTech Connect

    Weigel, P.; Lerma, C.; Hanson, A.D.

    1988-01-01

    Plants synthesize betaine by a two-step oxidation of choline (choline ..-->.. betaine aldehyde ..-->.. betaine). Protoplast-derived chloroplasts of spinach (Spinacia oleracea L.) carry out both reactions, more rapidly in light than in darkness. We investigated the light-stimulated oxidation of choline, using spinach chloroplasts isolated directly from leaves. The rates of choline oxidation obtained (dark and light rates: 10-50 and 100-300 nanomoles per hour per milligram chlorophyll, respectively) were approximately 20-fold higher than for protoplast-derived chloroplasts. Betaine aldehyde was the main product. Choline oxidation in darkness and light was suppressed by hypoxia. Neither uncouplers not the Calvin cycle inhibitor glyceraldehyde greatly affected choline oxidation in the light, and maximal choline oxidation was attained far below light saturation of CO/sub 2/ fixation. The light stimulation of choline oxidation was abolished by the PSII inhibitors DCMU and dibromothymoquinone, and was partially restored by adding reduced diaminodurene, an electron donor to PSI. Both methyl viologen and phenazine methosulfate prevented choline oxidation. Adding dihydroxyacetone phosphate, which can generate NADPH in organello, doubled the dark rate of choline oxidation. These results indicate that choline oxidation in chloroplasts requires oxygen, and reducing power generated from PSI. Enzymic reactions consistent with these requirements are discussed.

  5. Caffeine potentiates the enhancement by choline of striatal acetylcholine release

    NASA Technical Reports Server (NTRS)

    Johnson, D. A.; Ulus, I. H.; Wurtman, R. J.

    1992-01-01

    We investigated the effect of peripherally administered caffeine (50 mg/kg), choline (30, 60, or 120 mg/kg) or combinations of both drugs on the spontaneous release of acetylcholine (ACh) from the corpus striatum of anesthetized rats using in vivo microdialysis. Caffeine alone or choline in the 30 or 60 mg/kg dose failed to increase ACh in microdialysis samples; the 120 mg/kg choline dose significantly enhanced ACh during the 80 min following drug administration. Coadministration of caffeine with choline significantly increased ACh release after each of the choline doses tested. Peak microdialysate levels with the 120 mg/kg dose were increased 112% when caffeine was additionally administered, as compared with 54% without caffeine. These results indicate that choline administration can enhance spontaneous ACh release from neurons, and that caffeine, a drug known to block adenosine receptors on these neurons, can amplify the choline effect.

  6. A single-vial biphasic liquid extraction assay for choline acetyltransferease using (/sup 3/H)choline

    SciTech Connect

    Rand, J.B.; Johnson, C.D.

    1981-09-15

    A single-vial liquid extraction assay for choline acetyltransferase that uses (/sup 3/H)choline as the labeled substrate has been devised. (/sup 3/H)Choline is incubated with an excess of acetyl-CoA in a small reaction vial which also serves as a scintillation vial. After a suitable reaction period, unreacted (/sup 3/H)choline is quickly and quantitatively converted to phosphoryl-(/sup 3/H)choline by the addition of an excess of choline kinase. This treatment is followed by the addition of scintillation fluid containing sodium tetraphenylboron after which the vial is capped, shaken, and counted. A two-phase system is produced in which product (/sup 3/H)choline is selectively extracted into the scintillation fluid, where is is counted. Phosphoryl-(/sup 3/H)choline remains in the aqueous phase and is not counted. This assay is rapid, simple, and quite sensitive. In comparison to assays using acetyl-CoA as the labeled substrate, it is less sensitive to interference by other enzymes and thus more suitable for measuring choline acetyltransferase in crude extracts and in the initial stages of purificaton. Similar single-vial radiometric assays are described for choline kinase and acetyl-CoA hydrolases.

  7. Effect of choline carboxylate ionic liquids on biological membranes

    PubMed Central

    Rengstl, Doris; Kraus, Birgit; Van Vorst, Matthew; Elliott, Gloria D.; Kunz, Werner

    2015-01-01

    Choline carboxylates, ChCm, with m = 2–10 and choline oleate are known as biocompatible substances, yet their influence on biological membranes is not well-known, and the effect on human skin has not previously been investigated. The short chain choline carboxylates ChCm with m = 2, 4, 6 act as hydrotropes, solubilizing hydrophobic compounds in aqueous solution, while the longer chain choline carboxylates ChCm with m = 8,10 and oleate are able to form micelles. In the present study, the cytotoxicity of choline carboxylates was tested using HeLa and SK-MEL-28 cells. The influence of these substances on liposomes prepared from dipalmitoylphosphatidylcholine (DPPC) was also evaluated to provide insights on membrane interactions. It was observed that the choline carboxylates with a chain length of m > 8 distinctly influence the bilayer, while the shorter ones had minimal interaction with the liposomes. PMID:25444662

  8. Exercise and neuromodulators: choline and acetylcholine in marathon runners

    NASA Technical Reports Server (NTRS)

    Conlay, L. A.; Sabounjian, L. A.; Wurtman, R. J.

    1992-01-01

    Certain neurotransmitters (i.e., acetylcholine, catecholamines, and serotonin) are formed from dietary constituents (i.e., choline, tyrosine and tryptophan). Changing the consumption of these precursors alters release of their respective neurotransmitter products. The neurotransmitter acetylcholine is released from the neuromuscular junction and from brain. It is formed from choline, a common constituent in fish, liver, and eggs. Choline is also incorporated into cell membranes; membranes may likewise serve as an alternative choline source for acetylcholine synthesis. In trained athletes, running a 26 km marathon reduced plasma choline by approximately 40%, from 14.1 to 8.4 uM. Changes of similar magnitude have been shown to reduce acetylcholine release from the neuromuscular junction in vivo. Thus, the reductions in plasma choline associated with strenuous exercise may reduce acetylcholine release, and could thereby affect endurance or performance.

  9. Maternal choline supplementation: a nutritional approach for improving offspring health?

    PubMed

    Jiang, Xinyin; West, Allyson A; Caudill, Marie A

    2014-05-01

    The modulatory role of choline on the fetal epigenome and the impact of in utero choline supply on fetal programming and health are of great interest. Studies in animals and/or humans suggest that maternal choline supplementation during pregnancy benefits important physiologic systems such as offspring cognitive function, response to stress, and cerebral inhibition. Because alterations in offspring phenotype frequently coincide with epigenetic modifications and changes in gene expression, maternal choline supplementation may be a nutritional strategy to improve lifelong health of the child. Future studies are warranted to elucidate further the effect of choline on the fetal epigenome and to determine the level of maternal choline intake required for optimal offspring physiologic function. PMID:24680198

  10. Report: Affinity Chromatography.

    ERIC Educational Resources Information Center

    Walters, Rodney R.

    1985-01-01

    Supports, affinity ligands, immobilization, elution methods, and a number of applications are among the topics considered in this discussion of affinity chromatography. An outline of the basic principles of affinity chromatography is included. (JN)

  11. Choline or methionine reverses impaired secretion of VLDL by hepatocytes from choline-deficient rats

    SciTech Connect

    Yao, Z.; Vance, D.E.

    1987-05-01

    Male rats fed a choline-deficient (CD) diet for three days accumulated triacylglycerol (TG) in the liver. Hepatocytes from these rats were cultured and maintained in a medium + choline. The rate of secretion of TG was reduced by 50% in the CD cells. Correspondingly, (/sup 3/H)oleate and (/sup 3/H)glycerol were incorporated at a 2-fold higher rate into TG secreted by choline-supplemented cells compared to CD cells. Isolation of lipoprotein fractions by ultracentrifugation showed that the reduced secretion of TG by CD hepatocytes was mainly due to an impaired secretion of very low density lipoprotein (VLDL). Incorporation of (/sup 3/H)leucine into secreted apoB/sub H/, apoB/sub L/ and apoE was markedly reduced in CD cells compared to choline-supplemented cells. Secretion of high density lipoprotein was not reduced in the CD hepatocytes. Normal secretion of VLDL was resumed upon addition of methionine to the CD cells.

  12. Choline oxidation by intact chloroplasts isolated directly from spinach leaves

    SciTech Connect

    Weigel, P.; Hanson, A.D.

    1986-04-01

    Illuminated chloroplasts derived from spinach leaf protoplasts synthesize betaine from choline via the intermediate betaine aldehyde (BAL) (PNAS 82:3678). Photosynthetically active chloroplasts isolated directly from spinach leaves oxidized (/sup 14/C)choline in the light at rates 10 times higher (25-80 nmol/mg chl b) than protoplast-derived chloroplasts. Up to 20% of the (/sup 14/C)choline supplied during a 30 min incubation was oxidized in the light; the main product was (/sup 14/C)BAL. Rates of (/sup 14/C)choline oxidation in darkness were only 5-30% of rates in light. Light-dependent (/sup 14/C)choline oxidation was abolished by DCMU and 5 mM DTT. Pre-illumination of the chloroplasts did not promote (/sup 14/C)choline oxidation in darkness. The uncouplers nigericin and CCCP at concentrations which eliminated CO/sub 2/-dependent O/sub 2/ evolution did not affect (/sup 14/C)choline oxidation in the light. They hypothesize that (/sup 14/C)choline oxidation is not dependent upon light activation of an enzymatic system or upon the electrochemical proton gradient but requires an oxidant generated in the light.

  13. Legionella bozemanae synthesizes phosphatidylcholine from exogenous choline.

    PubMed

    Palusinska-Szysz, Marta; Janczarek, Monika; Kalitynski, Rafal; Dawidowicz, Andrzej L; Russa, Ryszard

    2011-02-20

    The phospholipid class and fatty acid composition of Legionella bozemanae were determined using thin-layer chromatography, gas-liquid chromatography, and matrix-assisted laser desorption ionization-time of flight mass spectrometry. Phosphatidylcholine, phosphatidylethanolamine, and diphosphatidylglycerol were the predominant phospholipids, while phosphatidyl-N-monomethylethanolamine, phosphatidylglycerol, and phosphatidyl-N,N-dimethylethanolamine were present at low concentrations. With the use of the LC/MS technique, PC16:0/15:0, PC17:/15:0, and PE16:1/15:0 were shown to be the dominant phospholipid constituents, which may be taxonomically significant. Two independent phosphatidylcholine synthesis pathways (the three-step methylation and the one-step CDP-choline pathway) were present and functional in L. bozemanae. In the genome of L. bozemanae, genes encoding two potential phosphatidylcholine forming enzymes, phospholipid N-methyl transferase (PmtA) and phosphatidylcholine synthase (Pcs), homologous to L. longbeachae, L. drancourtii, and L. pneumophila pmtA and pcs genes were identified. Genes pmtA and pcs from L. bozemanae were sequenced and analyzed on nucleotide and amino acid levels. Bacteria grown on an artificial medium with labelled choline synthesized phosphatidylcholine predominantly via the phosphatidylcholine synthase pathway, which indicates that L. bozemanae phosphatidylcholine, similarly as in other bacteria associated with eukaryotes, is an important determinant of host-microbe interactions. PMID:20338739

  14. Choline associated hypersexuality in a 79-year-old man.

    PubMed

    Calabrò, Rocco Salvatore; Cordici, Francesco; Genovese, Carmelo; Bramanti, Placido

    2014-01-01

    Hypersexuality, also referred to as sexually inappropriate behavior and sexual disinhibition, involves persistent, uninhibited sexual behaviors directed at oneself or at others, sometimes associated with neurodegenerative disorders. Choline is a water-soluble essential nutrient, used as a dietary supplement in different diseases. This report was aimed at considering choline intake as a possible cause of iatrogenic hypersexuality. After an evaluation, a 79-year-old man affected by memory loss was diagnosed with mild cognitive impairment and treated with oral choline. After 6 weeks of regular choline assumption, the patient showed a pathological increase in libido with sexual urges. As choline was withdrawn, the hypersexuality disappeared within 5 days. Since hypersexuality may be an underreported and overlooked adverse effect of drugs and dietary supplements acting on the cholinergic pathway, this should be considered when treating and counselling patients with inappropriate sexual behavior. PMID:23733158

  15. Substrate Binding and Catalytic Mechanism of Human Choline Acetyltransferase

    SciTech Connect

    Kim,A.; Rylett, J.; Shilton, B.

    2006-01-01

    Choline acetyltransferase (ChAT) catalyzes the synthesis of the neurotransmitter acetylcholine from choline and acetyl-CoA, and its presence is a defining feature of cholinergic neurons. We report the structure of human ChAT to a resolution of 2.2 {angstrom} along with structures for binary complexes of ChAT with choline, CoA, and a nonhydrolyzable acetyl-CoA analogue, S-(2-oxopropyl)-CoA. The ChAT-choline complex shows which features of choline are important for binding and explains how modifications of the choline trimethylammonium group can be tolerated by the enzyme. A detailed model of the ternary Michaelis complex fully supports the direct transfer of the acetyl group from acetyl-CoA to choline through a mechanism similar to that seen in the serine hydrolases for the formation of an acyl-enzyme intermediate. Domain movements accompany CoA binding, and a surface loop, which is disordered in the unliganded enzyme, becomes localized and binds directly to the phosphates of CoA, stabilizing the complex. Interactions between this surface loop and CoA may function to lower the K{sub M} for CoA and could be important for phosphorylation-dependent regulation of ChAT activity.

  16. Dietary intake and food sources of choline in European populations.

    PubMed

    Vennemann, Francy B C; Ioannidou, Sofia; Valsta, Liisa M; Dumas, Céline; Ocké, Marga C; Mensink, Gert B M; Lindtner, Oliver; Virtanen, Suvi M; Tlustos, Christina; D'Addezio, Laura; Mattison, Irene; Dubuisson, Carine; Siksna, Inese; Héraud, Fanny

    2015-12-28

    Choline is an important nutrient for humans. Choline intake of the European population was assessed considering the European Food Safety Authority European Comprehensive Food Consumption Database and the United States Department of Agriculture Nutrient Database. Average choline intake ranges were 151-210 mg/d among toddlers (1 to ≤3 years old), 177-304 mg/d among other children (3 to ≤10 years old), 244-373 mg/d among adolescents (10 to ≤18 years old), 291-468 mg/d among adults (18 to ≤65 years old), 284-450 mg/d among elderly people (65 to ≤75 years old) and 269-444 mg/d among very elderly people (≥75 years old). The intakes were higher among males compared with females, mainly due to larger quantities of food consumed per day. In most of the population groups considered, the average choline intake was below the adequate intake (AI) set by the Institute of Medicine in the USA. The main food groups contributing to choline intake were meat, milk, grain, egg and their derived products, composite dishes and fish. The main limitations of this study are related to the absence of choline composition data of foods consumed by the European population and the subsequent assumption made to assess their intake levels. Given the definition of AI, no conclusion on the adequacy of choline intake can be drawn for most European population groups. Such results improve the knowledge on choline intake in Europe that could be further refined by the collection of choline composition data for foods as consumed in Europe. PMID:26423357

  17. 11C-Choline and 18F-FDG PET/CT in the Detection of Occult Prostate Cancer in the Context of a Paraneoplastic Syndrome.

    PubMed

    Jiménez-Bonilla, Julio; Quirce, Remedios; Banzo, Ignacio; Martínez-Rodríguez, Isabel; Carril, José Manuel

    2015-08-01

    In a 73-year-old man, an occult neoplasm was suspected after 2 consecutive deep venous thrombosis, the latter under anticoagulant therapy and previous axonopathy. After normal CT and MRI findings, a requested (18)F-FDG PET/CT showed a focal uptake in the prostate. Because FDG uptake in the prostate is infrequent, a (11)C-choline PET/CT was indicated revealing a focal uptake in the same location. No other abnormalities were detected in the rest of the body. A guided biopsy by ultrasonography was performed revealing a prostate carcinoma and inflammation in both prostatic lobes. PMID:26018697

  18. Choline as a fuel sweetener and sulfur antagonist

    SciTech Connect

    Roof, G.L.; Porlier, B.W.; Cravey, W.E.

    1986-06-10

    A method is described of sweetening petroleum hydrocarbon fuels and, at the same time, reducing the sulfur content thereof which comprises treating such fuels with a sweetening and sulfur-removing amount of choline.

  19. Choline for neutralizing naphthenic acid in fuel and lubricating oils

    SciTech Connect

    Ries, D.G.; Roof, G.L.

    1986-07-15

    A method is described of neutralizing at least a portion of the naphthenic acids present in fuel and lubricating oils which contain naphthenic acids which comprises treating these oils with a neutralizing amount of choline.

  20. Specific Stimulated Uptake of Acetylcholine by Torpedo Electric Organ Synaptic Vesicles

    NASA Astrophysics Data System (ADS)

    Parsons, Stanley M.; Koenigsberger, Robert

    1980-10-01

    The specificity of acetylcholine uptake by synaptic vesicles isolated from the electric organ of Torpedo californica was studied. In the absence of cofactors, [3H]acetylcholine was taken up identically to [14C]choline in the same solution (passive uptake), and the equilibrium concentration achieved inside the vesicles was equal to the concentration outside. In the presence of MgATP, [3H]acetylcholine and [14C]choline in the same solution were taken up identically, except only about half as much of each was taken up (suppressed uptake). [3H]Acetylcholine uptake was stimulated by MgATP and HCO3 about 4-fold relative to suppressed uptake, for a net concentrative uptake of about 2:1 (stimulated uptake). Uptake of [14C]choline in the same solution remained at the suppressed level. [3H]Acetylcholine taken up under stimulated conditions migrated with vesicles containing [14C]mannitol on analytical glycerol density gradients during centrifugation. Vesicles were treated with nine protein modification reagents under mild conditions. Two reagents had no effect on, dithiothreitol potentiated, and six reagents strongly inhibited subsequent stimulated uptake of [3H]acetylcholine. The results indicate that uptake of acetylcholine is conditionally specific for the transported substrate, is carried out by the synaptic vesicles rather than a contaminant of the preparation, and requires a functional protein system containing a critical sulfhydryl group.

  1. Choline nutrition programs brain development via DNA and histone methylation.

    PubMed

    Blusztajn, Jan Krzysztof; Mellott, Tiffany J

    2012-06-01

    Choline is an essential nutrient for humans. Metabolically choline is used for the synthesis of membrane phospholipids (e.g. phosphatidylcholine), as a precursor of the neurotransmitter acetylcholine, and, following oxidation to betaine, choline functions as a methyl group donor in a pathway that produces S-adenosylmethionine. As a methyl donor choline influences DNA and histone methylation--two central epigenomic processes that regulate gene expression. Because the fetus and neonate have high demands for choline, its dietary intake during pregnancy and lactation is particularly important for normal development of the offspring. Studies in rodents have shown that high choline intake during gestation improves cognitive function in adulthood and prevents memory decline associated with old age. These behavioral changes are accompanied by electrophysiological, neuroanatomical, and neurochemical changes and by altered patterns of expression of multiple cortical and hippocampal genes including those encoding key proteins that contribute to the biochemical mechanisms of learning and memory. These actions of choline are observed long after the exposure to the nutrient ended (months) and correlate with fetal hepatic and cerebral cortical choline-evoked changes in global- and gene-specific DNA cytosine methylation and with dramatic changes of the methylation pattern of lysine residues 4, 9 and 27 of histone H3. Moreover, gestational choline modulates the expression of DNA (Dnmt1, Dnmt3a) and histone (G9a/Ehmt2/Kmt1c, Suv39h1/Kmt1a) methyltransferases. In addition to the central role of DNA and histone methylation in brain development, these processes are highly dynamic in adult brain, modulate the expression of genes critical for synaptic plasticity, and are involved in mechanisms of learning and memory. A recent study documented that in a cohort of normal elderly people, verbal and visual memory function correlated positively with the amount of dietary choline consumption

  2. Low-melting mixtures based on choline ionic liquids.

    PubMed

    Rengstl, Doris; Fischer, Veronika; Kunz, Werner

    2014-11-01

    In this article a strategy is proposed for the design of low toxic, room temperature liquid low-melting mixtures (LMMs) which are entirely composed of natural materials. From literature it is well known that, in general, deep eutectic solvents based on choline chloride and dicarboxylic acids are LMMs, but not liquids at room temperature, with one exception: a 1 : 1 molar mixture of malonic acid and choline chloride. Therefore, the starting point of this study was the decrease of the melting point of one of the components, namely the dicarboxylic acid, which is succinic, glutaric or adipic acid. For this purpose, one of the two protons of the acidic group was exchanged by a bulky unsymmetrical choline cation. The resulting ionic liquids (ILs) were still solid at room temperature, but have a reduced melting temperature compared to the corresponding acids. In the second step, mixtures of these ILs with choline chloride were prepared. It turned out that choline glutarate-choline chloride mixtures are liquids at room temperature at compositions containing 95-98 wt% of choline glutarate. Finally, urea was added as another hydrogen bond donor. Density, conductivity and viscosity measurements were performed for all obtained mixtures. Moreover, a Walden plot was drawn which indicates that all mixtures are liquids with fully dissociated ions moving independently. Therefore, they are considered as "good" ionic liquids and, thus, for example they can be used to exchange more toxic or less biodegradable ILs in application processes. A brief outlook containing application possibilities is given. It is demonstrated that choline dodecylsulfate is readily soluble in these mixtures, forming aggregates in the LMM at temperatures exceeding 55 °C. PMID:25242504

  3. Eosinophilic hepatitis after ingestion of choline magnesium trisalicylate.

    PubMed

    Nadkarni, M M; Peller, C A; Retig, J

    1992-01-01

    Choline magnesium trisalicylate is a non-acetylated salicylate used widely as a nonsteroidal anti-inflammatory drug. Although mild transient hepatotoxicity associated with aspirin and other salicylates has been well documented, most commonly with high-dose treatment for rheumatologic disorders 112), we report a case of severe hypersensitivity hepatitis with striking tissue and peripheral eosinophilia after ingestion of choline magnesium trisalicylate. PMID:1728115

  4. Overexpression, purification and crystallization of a choline-binding protein CbpI from Streptococcus pneumoniae

    SciTech Connect

    Paterson, Neil G. Riboldi-Tunicliffe, Alan; Mitchell, Timothy J.; Isaacs, Neil W.

    2006-07-01

    The choline-binding protein CbpI from S. pneumoniae has been purified and crystallized and diffraction data have been collected to 3.5 Å resolution. The choline-binding protein CbpI from Streptococcus pneumoniae is a 23.4 kDa protein with no known function. The protein has been successfully purified initially using Ni–NTA chromatography and to homogeneity using Q-Sepharose ion-exchange resin as an affinity column. CbpI was crystallized using PEG 3350 as a precipitant and X-ray crystallographic analysis showed that the crystals belonged to the tetragonal space group P4, with unit-cell parameters a = b = 83.31, c = 80.29 Å, α = β = γ = 90°. The crystal contains two molecules in the asymmetric unit with a solvent content of 55.7% (V{sub M} = 2.77 Å{sup 3} Da{sup −1}) and shows a diffraction limit of 3.5 Å.

  5. Choline Metabolism Alteration: A Focus on Ovarian Cancer

    PubMed Central

    Bagnoli, Marina; Granata, Anna; Nicoletti, Roberta; Krishnamachary, Balaji; Bhujwalla, Zaver M.; Canese, Rossella; Podo, Franca; Canevari, Silvana; Iorio, Egidio; Mezzanzanica, Delia

    2016-01-01

    Compared with normal differentiated cells, cancer cells require a metabolic reprograming to support their high proliferation rates and survival. Aberrant choline metabolism is a fairly new metabolic hallmark reflecting the complex reciprocal interactions between oncogenic signaling and cellular metabolism. Alterations of the involved metabolic network may be sustained by changes in activity of several choline transporters as well as of enzymes such as choline kinase-alpha (ChoK-α) and phosphatidylcholine-specific phospholipases C and D. Of note, the net outcome of these enzymatic alterations is an increase of phosphocholine and total choline-containing compounds, a “cholinic phenotype” that can be monitored in cancer by magnetic resonance spectroscopy. This review will highlight the molecular basis for targeting this pathway in epithelial ovarian cancer (EOC), a highly heterogeneous and lethal malignancy characterized by late diagnosis, frequent relapse, and development of chemoresistance. Modulation of ChoK-α expression impairs only EOC but not normal ovarian cells, thus supporting the hypothesis that “cholinic phenotype” is a peculiar feature of transformed cells and indicating ChoK-α targeting as a novel approach to improve efficacy of standard EOC chemotherapeutic treatments. PMID:27446799

  6. Metabolic crosstalk between choline/1-carbon metabolism and energy homeostasis.

    PubMed

    Zeisel, Steven H

    2013-03-01

    There are multiple identified mechanisms involved in energy metabolism, insulin resistance and adiposity, but there are here-to-fore unsuspected metabolic factors that also influence these processes. Studies in animal models suggest important links between choline/1-carbon metabolism and energy homeostasis. Rodents fed choline deficient diets become hypermetabolic. Mice with deletions in one of several different genes of choline metabolism have phenotypes that include increased metabolic rate, decreased body fat/lean mass ratio, increased insulin sensitivity, decreased ATP production by mitochondria, or decreased weight gain on a high fat diet. In addition, farmers have recognized that the addition of a metabolite of choline (betaine) to cattle and swine feed reduces body fat/lean mass ratio. Choline dietary intake in humans varies over a > three-fold range, and genetic variation exists that modifies individual requirements for this nutrient. Although there are some epidemiologic studies in humans suggesting a link between choline/1-carbon metabolism and energy metabolism, there have been no controlled studies in humans that were specifically designed to examine this relationship. PMID:23072856

  7. Metabolic crosstalk between choline/1-carbon metabolism and energy homeostasis

    PubMed Central

    Zeisel, Steven H.

    2013-01-01

    There are multiple identified mechanisms involved in energy metabolism, insulin resistance and adiposity, but there are here-to-fore unsuspected metabolic factors that also influence these processes. Studies in animal models suggest important links between choline/1-carbon metabolism and energy homeostasis. Rodents fed choline deficient diets become hypermetabolic. Mice with deletions in one of several different genes of choline metabolism have phenotypes that include increased metabolic rate, decreased body fat/lean mass ratio, increased insulin sensitivity, decreased ATP production by mitochondria, or decreased weight gain on a high fat diet. In addition, farmers have recognized that the addition of a metabolite of choline (betaine) to cattle and swine feed reduces body fat/lean mass ratio. Choline dietary intake in humans varies over a >three-fold range, and genetic variation exists that modifies individual requirements for this nutrient. Although there are some epidemiologic studies in humans suggesting a link between choline/1-carbon metabolism and energy metabolism, there have been no controlled studies in humans that were specifically designed to examine this relationship. PMID:23072856

  8. Four cation-selective transporters contribute to apical uptake and accumulation of metformin in Caco-2 cell monolayers.

    PubMed

    Han, Tianxiang Kevin; Proctor, William R; Costales, Chester L; Cai, Hao; Everett, Ruth S; Thakker, Dhiren R

    2015-03-01

    Metformin is the frontline therapy for type II diabetes mellitus. The oral bioavailability of metformin is unexpectedly high, between 40 and 60%, given its hydrophilicity and positive charge at all physiologic pH values. Previous studies in Caco-2 cell monolayers, a cellular model of the human intestinal epithelium, showed that during absorptive transport metformin is taken up into the cells via transporters in the apical (AP) membrane; however, predominant transport to the basolateral (BL) side occurs via the paracellular route because intracellular metformin cannot egress across the BL membrane. Furthermore, these studies have suggested that the AP transporters can contribute to intestinal accumulation and absorption of metformin. Transporter-specific inhibitors as well as a novel approach involving a cocktail of transporter inhibitors with overlapping selectivity were used to identify the AP transporters that mediate metformin uptake in Caco-2 cell monolayers; furthermore, the relative contributions of these transporters in metformin AP uptake were also determined. The organic cation transporter 1, plasma membrane monoamine transporter (PMAT), serotonin reuptake transporter, and choline high-affinity transporter contributed to approximately 25%, 20%, 20%, and 15%, respectively, of the AP uptake of metformin. PMAT-knockdown Caco-2 cells were constructed to confirm the contribution of PMAT in metformin AP uptake because a PMAT-selective inhibitor is not available. The identification of four intestinal transporters that contribute to AP uptake and potentially intestinal absorption of metformin is a significant novel finding that can influence our understanding of metformin pharmacology and intestinal drug-drug interactions involving this highly prescribed drug. PMID:25563903

  9. 18F-FET and 18F-FCH uptake in human glioblastoma T98G cell lines

    PubMed Central

    Persico, Marco Giovanni; Buroni, Federica Eleonora; Pasi, Francesca; Aprile, Carlo; Nano, Rosanna; Hodolic, Marina

    2016-01-01

    Abstract Background Despite complex treatment of surgery, radiotherapy and chemotherapy, high grade gliomas often recur. Differentiation between post-treatment changes and recurrence is difficult. 18F-methyl-choline (18F-FCH) is frequently used in staging and detection of recurrent prostate cancer disease as well as some brain tumours; however accumulation in inflammatory tissue limits its specificity. The 18F-ethyl-tyrosine (18F-FET) shows a specific uptake in malignant cells, resulting from increased expression of amino acid transporters or diffusing through the disrupted blood-brain barrier. 18F-FET exhibits lower uptake in machrophages and other inflammatory cells. Aim of this study was to evaluate 18F-FCH and 18F-FET uptake by human glioblastoma T98G cells. Material and methods Human glioblastoma T98G or human dermal fibroblasts cells, seeded at a density to obtain 2 × 105 cells per flask when radioactive tracers were administered, grew adherent to the plastic surface at 37°C in 5% CO2 in complete medium. Equimolar amounts of radiopharmaceuticals were added to cells for different incubation times (20 to 120 minutes) for 18F-FCH and 18F-FET respectively. The cellular radiotracer uptake was determined with a gamma counter. All experiments were carried out in duplicate and repeated three times. The uptake measurements are expressed as the percentage of the administered dose of tracer per 2 × 105 cells. Data (expressed as mean values of % uptake of radiopharmaceuticals) were compared using parametric or non-parametric tests as appropriate. Differences were regarded as statistically significant when p<0.05. Results A significant uptake of 18F-FCH was seen in T98G cells at 60, 90 and 120 minutes. The percentage uptake of 18F-FET in comparison to 18F-FCH was lower by a factor of more than 3, with different kinetic curves.18F-FET showed a more rapid initial uptake up to 40 minutes and 18F-FCH showed a progressive rise reaching a maximum after 90 minutes

  10. 11C-choline vs. 18F-FDG PET/CT in assessing bone involvement in patients with multiple myeloma

    PubMed Central

    Nanni, Cristina; Zamagni, Elena; Cavo, Michele; Rubello, Domenico; Tacchetti, Paola; Pettinato, Cinzia; Farsad, Mohsen; Castellucci, Paolo; Ambrosini, Valentina; Montini, Gian Carlo; Al-Nahhas, Adil; Franchi, Roberto; Fanti, Stefano

    2007-01-01

    Background Multiple Myeloma (MM) is a B cell neoplasm causing lytic or osteopenic bone abnormalities. Whole body skeletal survey (WBSS), Magnetic resonance (MR) and 18F-FDG PET/CT are imaging techniques routinely used for the evaluation of bone involvement in MM patients. Aim As MM bone lesions may present low 18F-FDG uptake; the aim of this study was to assess the possible added value and limitations of 11C-Choline to that of 18F-FDG PET/CT in patients affected with MM. Methods Ten patients affected with MM underwent a standard 11C-Choline PET/CT and an 18F-FDG PET/CT within one week. The results of the two scans were compared in terms of number, sites and SUVmax of lesions. Results Four patients (40%) had a negative concordant 11C-Choline and 18F-FDG PET/CT scans. Two patients (20%) had a positive 11C-Choline and 18F-FDG PET/CT scans that identified the same number and sites of bone lesions. The remaining four patients (40%) had a positive 11C-Choline and 18F-FDG PET/CT scan, but the two exams identified different number of lesions. Choline showed a mean SUVmax of 5 while FDG showed a mean SUVmax of 3.8 (P = 0.042). Overall, 11C-Choline PET/CT scans detected 37 bone lesions and 18F-FDG PET/CT scans detected 22 bone lesions but the difference was not significant (P = 0.8). Conclusion According to these preliminary data, 11C-Choline PET/CT appears to be more sensitive than 18F-FDG PET/CT for the detection of bony myelomatous lesions. If these data are confirmed in larger series of patients, 11C-Choline may be considered a more appropriate functional imaging in association with MRI for MM bone staging. PMID:17584499

  11. Lymph Node Metastasis from Tall-Cell Thyroid Cancer Negative on 18F-FDG PET/CT and Detected by 18F-Choline PET/CT.

    PubMed

    Piccardo, Arnoldo; Massollo, Michela; Bandelloni, Roberto; Arlandini, Anselmo; Foppiani, Luca

    2015-08-01

    A 77-year-old woman underwent thyroidectomy and (131)I remnant ablation for tall-cell differentiated cancer (DTC) of the left lobe. Detectable Tg levels (4.1 μg/L) under TSH suppression, with undetectable serum Tg-antibody levels, prompted neck ultrasonography, which revealed a lymph node in the left laterocervical region and in the right retroclavicular region. (18)F-FDG PET/CT showed uptake by the left lymph node. (18)F-choline PET/CT showed increased uptake by both lymph nodes. Histopathology revealed DTC solid metastasis in the left lymph node and solid and cystic metastasis in the right one. (18)F-choline PET/CT can locate virulent DTC recurrence, thereby increasing (18)F-FDG PET/CT information. PMID:26053727

  12. The role of rumen-protected choline in hepatic function and performance of transition dairy cows.

    PubMed

    Shahsavari, Arash; D'Occhio, Michael J; Al Jassim, Rafat

    2016-07-01

    High-producing dairy cows enter a period of negative energy balance during the first weeks of lactation. Energy intake is usually sufficient to cover the increase in energy requirements for fetal growth during the period before calving, but meeting the demand for energy is often difficult during the early stages of lactation. A catabolic state predominates during the transition period, leading to the mobilisation of energy reserves (NEFA and amino acids) that are utilised mainly by the liver and muscle. Increased uptake of mobilised NEFA by the liver, combined with the limited capacity of hepatocytes to either oxidise fatty acids for energy or to incorporate esterified fatty acids into VLDL results in fatty liver syndrome and ketosis. This metabolic disturbance can affect the general health, and it causes economic losses. Different nutritional strategies have been used to restrict negative effects associated with the energy challenge in transition cows. The provision of choline in the form of rumen-protected choline (RPC) can potentially improve liver function by increasing VLDL exportation from the liver. RPC increases gene expression of microsomal TAG transfer protein and APOB100 that are required for VLDL synthesis and secretion. Studies with RPC have looked at gene expression, metabolic hormones, metabolite profiles, milk production and postpartum reproduction. A reduction in liver fat and enhanced milk production has been observed with RPC supplementation. However, the effects of RPC on health and reproduction are equivocal, which could reflect the lack of sufficient dose-response studies. PMID:27138530

  13. Maternal dietary choline deficiency alters angiogenesis in fetal mouse hippocampus.

    PubMed

    Mehedint, Mihai G; Craciunescu, Corneliu N; Zeisel, Steven H

    2010-07-20

    We examined whether maternal dietary choline modulates angiogenesis in fetal brain. Pregnant C57BL/6 mice were fed either a choline-deficient (CD), control (CT), or choline-supplemented diet (CS) from days 12 to 17 (E12-17) of pregnancy and then fetal brains were studied. In CD fetal hippocampus, proliferation of endothelial cells (EC) was decreased by 32% (p < 0.01 vs. CT or CS) while differentiated EC clusters (expressing factor VIII related antigen (RA)) increased by 25% (p < 0.01 vs. CT or CS). These changes were associated with > 25% decrease in the number of blood vessels in CD fetal hippocampus (p < 0.01 vs. CT and CS), with no change in total cross-sectional area of these blood vessels. Expression of genes for the angiogenic signals derived from both endothelial and neuronal progenitor cells (NPC) was increased in CD fetal hippocampus VEGF C (Vegfc), 2.0-fold, p < 0.01 vs. CT and angiopoietin 2 (Angpt2), 2.1-fold, (p < 0.01 vs. CT)). Similar increased expression was observed in NPC isolated from E14 fetal mouse brains and exposed to low (5 microM), CT (70 microM), or high choline (280 microM) media for 72 h (low choline caused a 9.7-fold increase in relative gene expression of Vegfc (p < 0.001 vs. CT and high) and a 3.4-fold increase in expression of Angpt2, (p < 0.05 vs. CT and high). ANGPT2 protein was increased 42.2% (p < 0.01). Cytosine-phosphate-guanine dinucleotide islands in the proximity of the promoter areas of Vegfc and Angpt2 were hypomethylated in low choline NPC compared to CT NPC (p < 0.01). We conclude that maternal dietary choline intake alters angiogenesis in the developing fetal hippocampus. PMID:20624989

  14. Hyperosmolar sodium chloride is toxic to cultured neurons and causes reduction of glucose metabolism and ATP levels, an increase in glutamate uptake, and a reduction in cytosolic calcium.

    PubMed

    Morland, Cecilie; Pettersen, Mi Nguyen; Hassel, Bjørnar

    2016-05-01

    Elevation of serum sodium, hypernatremia, which may occur during dehydration or treatment with sodium chloride, may cause brain dysfunction and damage, but toxic mechanisms are poorly understood. We found that exposure to excess NaCl, 10-100mmol/L, for 20h caused cell death in cultured cerebellar granule cells (neurons). Toxicity was due to Na(+), since substituting excess Na(+) with choline reduced cell death to control levels, whereas gluconate instead of excess Cl(-) did not. Prior to cell death from hyperosmolar NaCl, glucose consumption and lactate formation were reduced, and intracellular aspartate levels were elevated, consistent with reduced glycolysis or glucose uptake. Concomitantly, the level of ATP became reduced. Pyruvate, 10mmol/L, reduced NaCl-induced cell death. The extracellular levels of glutamate, taurine, and GABA were concentration-dependently reduced by excess NaCl; high-affinity glutamate uptake increased. High extracellular [Na(+)] caused reduction in intracellular free [Ca(2+)], but a similar effect was seen with mannitol, which was not neurotoxic. We suggest that inhibition of glucose metabolism with ensuing loss of ATP is a neurotoxic mechanism of hyperosmolar sodium, whereas increased uptake of extracellular neuroactive amino acids and reduced intracellular [Ca(2+)] may, if they occur in vivo, contribute to the cerebral dysfunction and delirium described in hypernatremia. PMID:26994581

  15. Serum Levels of Choline-Containing Compounds Are Associated with Aerobic Fitness Level: The HUNT-Study

    PubMed Central

    Aspenes, Stian T.; Giskeødegård, Guro F.; Gribbestad, Ingrid S.; Wisløff, Ulrik; Bathen, Tone F.

    2012-01-01

    Background Cardiovascular disease (CVD) is a leading cause of death worldwide, and the number of people at risk is continuously growing. New methods for early risk prediction are therefore needed to actuate prevention strategies before the individuals are diagnosed with CVD. Several studies report that aerobic fitness level, measured as maximal oxygen uptake (VO2max), is the single best predictor of future CVD mortality in healthy people. Based on this, we wanted to study differences between healthy individuals with a large difference in VO2max-level to identify new biomarkers of low aerobic fitness that may also have potential as early biomarkers of CVD risk. Methodology/Principal Findings Serum samples from 218 healthy individuals with a low VO2max (n = 108, 63 women) or high VO2max (n = 110, 64 women) were analysed with MR metabolomics. In addition, standard clinical-chemical analyses for glucose, lipids, liver enzymes, micro-CRP, and colorimetric analysis on circulating choline were performed. Individuals in the low VO2max-group had increased serum levels of free choline, decreased phosphatidylcholine, increased glucosę and decreased unsaturated fatty acids compared to the individuals in the high VO2max–group. Conclusions/Significance Aerobic fitness dependent differences in serum levels of free choline and phosphatidylcholine are observed. They should be further studied as potential early markers of CVD risk. PMID:22860113

  16. WAY-855 (3-amino-tricyclo[2.2.1.02.6]heptane-1,3-dicarboxylic acid): a novel, EAAT2-preferring, nonsubstrate inhibitor of high-affinity glutamate uptake

    PubMed Central

    Dunlop, John; Eliasof, Scott; Stack, Gary; McIlvain, H Beal; Greenfield, Alexander; Kowal, Dianne; Petroski, Robert; Carrick, Tikva

    2003-01-01

    The pharmacological profile of a novel glutamate transport inhibitor, WAY-855 (3-amino-tricyclo[2.2.1.02.6]heptane-1,3-dicarboxylic acid), on the activity of the human forebrain glutamate transporters EAAT1, EAAT2 and EAAT3 expressed in stable mammalian cell lines and in Xenopus laevis oocytes is presented. WAY-855 inhibited glutamate uptake mediated by all three subtypes in a concentration-dependent manner, with preferential inhibition of the CNS-predominant EAAT2 subtype in both cells and oocytes. IC50 values for EAAT2 and EAAT3 inhibition in cells were 2.2 and 24.5 μM, respectively, while EAAT1 activity was inhibited by 50% at 100 μM (IC50 values determined in oocytes were 1.3 μM (EAAT2), 52.5 μM (EAAT3) and 125.9 μM (EAAT1)). Application of WAY-855 to EAAT-expressing oocytes failed to induce a transporter current, and the compound failed to exchange with accumulated [3H]D-aspartate in synaptosomes consistent with a nonsubstrate inhibitor. WAY-855 inhibited D-aspartate uptake into cortical synaptosomes by a competitive mechanism, and with similar potency to that observed for the cloned EAAT2. WAY-855 failed to agonise or antagonise ionotropic glutamate receptors in cultured hippocampal neurones, or the human metabotropic glutamate receptor subtype 4 expressed in a stable cell line. WAY-855 represents a novel structure in glutamate transporter pharmacology, and exploration of this structure might provide insights into the discrimination between EAAT2 and other EAAT subtypes. PMID:14517179

  17. Ultraviolet radiation alters choline phospholipid metabolism in human keratinocytes

    SciTech Connect

    DeLeo, V.; Scheide, S.; Meshulam, J.; Hanson, D.; Cardullo, A.

    1988-10-01

    Ultraviolet radiation B (UVB-290-320 nm) induces inflammation and hyperproliferation in human epidermis. This response is associated with the recovery from irradiated skin of inflammatory mediators derived from membrane phospholipids. We have previously reported that UVB stimulates the production of such mediators by human keratinocytes (HK) in culture. In these studies we examined the effect of UVB on the metabolism of choline containing phospholipids in HK prelabeled with (/sup 3/H) choline. UVB (400-1600J/m2) stimulated a dose dependent release of (/sup 3/H) choline from HK within minutes of irradiation. Examination of media extracts by paper chromatography revealed that the released (/sup 3/H) choline was predominately in the form of glycerophosphorylcholine. Examination of label remaining in membranes of cells after irradiation by acid precipitation and HPLC revealed that the origin of the released (/sup 3/H) choline was the membrane phosphatidylcholine/lysophosphatidylcholine. These data support a concept of UVB stimulation of both a phospholipase A (1 or 2) and a lysophospholipase. These UVB induced alterations of HK membrane phospholipid metabolism likely have profound effects on UVB-induced inflammation and control of cell growth in human skin.

  18. No evidence for role of extracellular choline-acetyltransferase in generation of gamma oscillations in rat hippocampal slices in vitro.

    PubMed

    Hollnagel, J O; ul Haq, R; Behrens, C J; Maslarova, A; Mody, I; Heinemann, U

    2015-01-22

    Acetylcholine (ACh) is well known to induce persistent γ-oscillations in the hippocampus when applied together with physostigmine, an inhibitor of the ACh degrading enzyme acetylcholinesterase (AChE). Here we report that physostigmine alone can also dose-dependently induce γ-oscillations in rat hippocampal slices. We hypothesized that this effect was due to the presence of choline in the extracellular space and that this choline is taken up into cholinergic fibers where it is converted to ACh by the enzyme choline-acetyltransferase (ChAT). Release of ACh from cholinergic fibers in turn may then induce γ-oscillations. We therefore tested the effects of the choline uptake inhibitor hemicholinium-3 (HC-3) on persistent γ-oscillations either induced by physostigmine alone or by co-application of ACh and physostigmine. We found that HC-3 itself did not induce γ-oscillations and also did not prevent physostigmine-induced γ-oscillation while washout of physostigmine and ACh-induced γ-oscillations was accelerated. It was recently reported that ChAT might also be present in the extracellular space (Vijayaraghavan et al., 2013). Here we show that the effect of physostigmine was prevented by the ChAT inhibitor (2-benzoylethyl)-trimethylammonium iodide (BETA) which could indicate extracellular synthesis of ACh. However, when we tested for effects of extracellularly applied acetyl-CoA, a substrate of ChAT for synthesis of ACh, physostigmine-induced γ-oscillations were attenuated. Together, these findings do not support the idea that ACh can be synthesized by an extracellularly located ChAT. PMID:25453770

  19. A molecular dynamics study of the ionic liquid, choline acetate.

    PubMed

    Willcox, Jon A L; Kim, Hyunjin; Kim, Hyung J

    2016-06-01

    Structural and dynamic properties of the ionic liquid (IL) choline acetate are studied using molecular dynamics (MD) simulations. The hydroxyl group of choline shows significant hydrogen-bonding interactions with the oxygen atoms of acetate. Nearly all choline cations are found to form a hydrogen bond with acetate anions at 400 K, while about 67% of cations participate in hydrogen-bonding interactions at 600 K. At 400 K, subdiffusive and prominent non-Gaussian behavior persist for t > 10 ns. At 600 K, the usual diffusion regime is obtained after a few hundred ps of subdiffusive behavior. Analysis of reorientational motions of acetate ions, particularly those of their short axes, indicates a high degree of dynamic heterogeneity, in agreement with previous work on different IL systems. PMID:27188287

  20. Characterization of Leishmania major phosphatidylethanolamine methyltransferases LmjPEM1 and LmjPEM2 and their inhibition by choline analogs.

    PubMed

    Bibis, Stergios S; Dahlstrom, Kelly; Zhu, Tongtong; Zufferey, Rachel

    2014-09-01

    Phosphatidylcholine (PC) is the most abundant phospholipid in the membranes of the human parasite Leishmania. It is synthesized via two metabolic routes, the de novo pathway that starts with the uptake of choline, and the threefold methylation of phosphatidylethanolamine. Choline was shown to be dispensable for Leishmania; thus, the methylation pathway likely represents the primary route for PC production. Here, we have identified and characterized two phosphatidylethanolamine methyltransferases, LmjPEM1 and LmjPEM2. Both enzymes are expressed in promastigotes as well as in the vertebrate form amastigotes, suggesting that these methyltransferases are important for the development of the parasite throughout its life cycle. These enzymes are maximally expressed during the log phase of growth which correlates with the demand of PC synthesis during cell multiplication. Immunofluorescence studies combined with cell fractionation have shown that both methyltransferases are localized at the endoplasmic reticulum membrane. Heterologous expression in yeast has demonstrated that LmjPEM1 and LmjPEM2 complement the choline auxotrophy phenotype of a yeast double null mutant lacking phosphatidylethanolamine methyltransferase activity. LmjPEM1 catalyzes the first, and to a lesser extent, the second methylation reaction. In contrast, LmjPEM2 has the capacity to add the second and third methyl group onto phosphatidylethanolamine to yield (lyso)PC; it can also add the first methyl group, albeit with very low efficiency. Finally, we have demonstrated using inhibition studies with choline analogs that miltefosine and octadecyltrimethylammonium bromide are potent inhibitors of this metabolic pathway. PMID:25176160

  1. A computational study on choline benzoate and choline salicylate ionic liquids in the pure state and after CO2 adsorption.

    PubMed

    Aparicio, Santiago; Atilhan, Mert

    2012-08-01

    Choline-based ionic liquids show very adequate environmental, toxicological, and economical profiles for their application in many different technological areas. We report in this work a computational study on the properties of choline benzoate and choline salicylate ionic liquids, as representatives of this family of compounds, in the pure state and after CO(2) adsorption. Quantum chemistry calculations using the density functional theory approach for ionic pairs and ions, CO(2) pairs, were carried out, and the results analyzed using natural bond orbital and atoms in a molecule approaches. Classical molecular dynamics simulations of ionic liquids were done as a function of pressure, temperature, and CO(2) concentration. Microscopic structuring and intermolecular forces are analyzed together with the dynamic behavior of the studied fluids. PMID:22738425

  2. Mechanisms of Ca uptake in high K/low Na solutions

    SciTech Connect

    Lodge, N.J.; Gelband, H.

    1986-03-05

    Ca uptake into neonatal rat atrium was measured with /sup 45/Ca. Extracellular /sup 45/Ca was displaced by washing tissues (45 min) in ice-cold Tyrode's containing 6.8 mM Ca/5 mM EGTA. Unless otherwise stated, solutions were pH balanced with HCO/sub 3//PO/sub 4//CO/sub 2/. Solutions in which 129 mM K or choline were substituted for 129 mM Na significantly stimulated Ca uptake (p < 0.001 for both). Inhibition of the Na/K pump (0 mM K solution), to increase intracellular Na, increased subsequent Ca uptakes measured in control, choline/low Na and high K/low Na solutions. The choline/low Na-stimulated uptake was increased by 104% while the high K/low Na stimulated uptake was increased only 11%. Cadmium (0.01-10 mM) blockade of the choline/low Na and high K/low Na uptakes was tested. Hepes buffered (HCO/sub 3//PO/sub 4//CO/sub 2/-free) solutions were used to avoid precipitation of Cd salts. The high K/low Na (Hepes) uptake was significantly (p < 0.001) greater than control and was 50% inhibited by 0.3 mM Cd. Choline/low Na in Hepes buffer increased Ca uptake only 5.1 +/- 4.3 ..mu..mol/kg (n=22) above control. In separate experiments, the choline/low Na (Hepes)-stimulated uptake (12.8 +/- 4.3 ..mu..mol/kg, n=8) was increased to 29.3 +/- 4.7 ..mu..mol/kg (n=8) by the addition of 1.8 mM PO/sub 4/. This intervention reduced the high K/low Na (Hepes)-stimulated uptake (47.1 +/- 6.4 ..mu..mol/kg, n=8) to 33.8 +/- 4.5 ..mu..mol/kg (n=8). They hypothesize that the uptake of Ca, induced by solutions of elevated K and lowered Na, is mediated by a minimum of two mechanisms; one stimulated by PO/sub 4/ and sensitive to transmembrane ion gradients, the other reduced by PO/sub 4/ and relatively insensitive to ion gradients.

  3. Fine-tuning of choline metabolism is important for pneumococcal colonization.

    PubMed

    Johnston, Calum; Hauser, Christoph; Hermans, Peter W M; Martin, Bernard; Polard, Patrice; Bootsma, Hester J; Claverys, Jean-Pierre

    2016-06-01

    The human pathogen Streptococcus pneumoniae (the pneumococcus) is rare in having a strict requirement for the amino alcohol choline, which decorates pneumococcal teichoic acids. This process relies on the lic locus, containing the lic1 and lic2 operons. These operons produce eight proteins that import and metabolize choline, generate teichoic acid precursors and decorate these with choline. Three promoters control expression of lic operons, with Plic1P1 and Plic1P2 controlling lic1 and Plic2 controlling lic2. To investigate the importance of lic regulation for pneumococci, we assayed the activity of transcriptional fusions of the three lic promoters to the luciferase reporter gene. Plic1P1 , whose activity depends on the response regulator CiaR, responded to fluctuations in extracellular choline, with activity increasing greatly upon choline depletion. We uncovered a complex regulatory mechanism controlling Plic1P1 , involving activity driven by CiaR, repression by putative repressor LicR in the presence of choline, and derepression upon choline depletion mediated by LicC, a choline metabolism enzyme. Finally, the ability to regulate Plic1P1 in response to choline was important for pneumococcal colonization. We suggest that derepression of Plic1P1 upon choline depletion maximizing choline internalization constitutes an adaptive response mechanism allowing pneumococci to optimize growth and survival in environments where choline is scarce. PMID:26919406

  4. Different Pathways of Choline Metabolism in Two Choline-Independent Strains of Streptococcus pneumoniae and Their Impact on Virulence▿

    PubMed Central

    Kharat, Arun S.; Denapaite, Dalia; Gehre, Florian; Brückner, Reinhold; Vollmer, Waldemar; Hakenbeck, Regine; Tomasz, Alexander

    2008-01-01

    The two recently characterized Streptococcus pneumoniae strains—R6Chi and R6Cho−—that have lost the unique auxotrophic requirement of this bacterial species for choline differ in their mechanisms of choline independence. In strain R6Chi the mechanism is caused by a point mutation in tacF, a gene that is part of the pneumococcal lic2 operon, which is essential for growth and survival of the bacteria. Cultures of lic2 mutants of the encapsulated strain D39Chi growing in choline-containing medium formed long chains, did not autolyze, had no choline in their cell wall, and were completely avirulent in the mouse intraperitoneal model. In contrast, while the Cho− strain carried a complete pneumococcal lic2 operon and had no mutations in the tacF gene, deletion of the entire lic2 operon had no effect on the growth or phenotype of strain Cho−. These observations suggest that the biochemical functions normally dependent on determinants of the pneumococcal lic2 operon may also be carried out in strain Cho− by a second set of genetic elements imported from Streptococcus oralis, the choline-independent streptococcal strain that served as the DNA donor in the heterologous transformation event that produced strain R6Cho−. The identification in R6Cho− of a large (20-kb) S. oralis DNA insert carrying both tacF and licD genes confirms this prediction and suggests that these heterologous elements may represent a “backup” system capable of catalyzing P-choline incorporation and export of teichoic acid chains under conditions in which the native lic2 operon is not functional. PMID:18621904

  5. Isolation and Characterization of Phosphatidyl Choline from Spinach Leaves.

    ERIC Educational Resources Information Center

    Devor, Kenneth A.

    1979-01-01

    This inexpensive but informative experiment for undergraduate biochemistry students involves isolating phosphatidyl choline from spinach leaves. Emphasis is on introducing students to techniques of lipid extraction, separation of lipids, identification using thin layer chromatography, and identification of fatty acids. Three periods of three hours…

  6. Effects of cytidine diphosphate choline on rats with memory deficits.

    PubMed

    Petkov, V D; Kehayov, R A; Mosharrof, A H; Petkov, V V; Getova, D; Lazarova, M B; Vaglenova, J

    1993-08-01

    The effects of cytidine diphosphate choline (CDP-choline, CAS 987-78-0) on learning and memory in rats with memory deficits were examined using behavioral methods of active avoidance with punishment reinforcement (shuttle-box), passive avoidance with punishment reinforcement (step-through and step-down), and active avoidance with positive (alimentary) reinforcement (staircase-maze). In the majority of experiments CDP-choline was applied orally at doses of 10-50 or 100 mg/kg daily for 7 days before the training session. The experiments were carried out on young-adult (aged 5 months) and old (aged 22 months) rats and on rats with a low capability for retention of learned behavior. Memory deficits were induced by the muscarinic cholinoceptor antagonist scopolamine (in young and old rats and mice), by the alpha 2-adrenoceptor agonist clonidine, by electroconvulsive shock, and by hypoxy. Memory deficits were also induced in rats offspring of dams that had been exposed to alcohol during pregnancy and lactation. The results suggest that CDP-choline acts as a memory-enhancing drug and that its effect is particularly pronounced in animals with memory deficits. PMID:8216435

  7. Fish meal lecithin as alternative precursor of docosahexaenoate and choline.

    PubMed

    Dahlan, W; Chatnilbandhu, S; Na-Nagara, B; Carpentier, Y A

    1996-09-01

    Choline and docosahexaenoate (DHA) are essential nutrients for maintaining normal brain function. However, their existence in fish lecithin is ignored and excluded during the degumming step of conventional fish oil manufacturing process. The study aims to introduce fish lecithin as alternative precursor of choline and omega-3 fatty acids especially DHA for nutritional supplements. Four grades of Thai fish meals with protein contents ranging from 60-70% were used. Their lipid characteristics were examined. Fish meal's fats and lecithin were 9-15 and 2-3 g/100 g, respectively. Total fatty acids constitute 23-27% monoenes without erucic acid and 24-28% polyenes including 15-19% DHA. Lecithin with 50% purity was prepared from grade-1 fish meal by means of consecutive methanol/n-hexane/acetone extraction. The obtained lecithin contains choline upto 66-70 mole% with DHA reaches to 20-23%. Its peroxide value of 57 and acid value of 9 are accepted for food grade lecithin preparation, however, the further refinery process is still suggested. Since the world consumption of nutritional supplement foods is increasing steadily, the results of our study implies that fish lecithin is probably a promising source of choline and omega-3 fatty acids especially DHA for such an objective. PMID:8886341

  8. Assay, Purification, and Partial Characterization of Choline Monooxygenase from Spinach.

    PubMed Central

    Burnet, M.; Lafontaine, P. J.; Hanson, A. D.

    1995-01-01

    The osmoprotectant glycine betaine is synthesized via the path-way choline -> betaine aldehyde -> glycine betaine. In spinach (Spinacia oleracea), the first step is catalyzed by choline monooxygenase (CMO), and the second is catalyzed by betaine aldehyde dehydrogenase. Because betaine aldehyde is unstable and not easily detected, we developed a coupled radiometric assay for CMO. [14C]Choline is used as substrate; NAD+ and betaine aldehyde dehydrogenase prepared from Escherichia coli are added to oxidize [14C]betaine aldehyde to [14C]glycine betaine, which is isolated by ion exchange. The assay was used in the purification of CMO from leaves of salinized spinach. The 10-step procedure included polyethylene glycol precipitation, polyethyleneimine precipitation, hydrophobic interaction, anion exchange on choline-Sepharose, dimethyldiethanolamine-Sepharose, and Mono Q, hydroxyapatite, gel filtration, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Following gel filtration, overall purification was about 600-fold and recovery of activity was 0.5%. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a polypeptide with a molecular mass of 45 kD. Taken with the value of 98 kD estimated for native CMO (R. Brouquisse, P. Weigel, D. Rhodes, C.F. Yocum, A.D. Hanson [1989] Plant Physiol 90: 322-329), this indicates that CMO is a homodimer. CMO preparations were red-brown, showed absorption maxima at 329 and 459 nm, and lost color upon dithionite addition, suggesting that CMO is an iron-sulfur protein. PMID:12228495

  9. Spatial memory and hippocampal plasticity are differentially sensitive to the availability of choline in adulthood as a function of choline supply in utero

    PubMed Central

    Wong-Goodrich, Sarah J.E.; Glenn, Melissa J.; Mellott, Tiffany J.; Blusztajn, Jan K.; Meck, Warren H.; Williams, Christina L.

    2009-01-01

    Altered dietary choline availability early in life leads to persistent changes in spatial memory and hippocampal plasticity in adulthood. Developmental programming by early choline nutrition may determine the range of adult choline intake that is optimal for the types of neural plasticity involved in cognitive function. To test this, male Sprague-Dawley rats were exposed to a choline chloride deficient (DEF), sufficient (CON), or supplemented (SUP) diet during embryonic days 12-17 and then returned to a control diet (1.1 g choline chloride/kg). At 70 days of age, we found that DEF and SUP rats required fewer choices to locate 8 baited arms of a 12-arm radial maze than CON rats. When switched to a choline-deficient diet (0 g/kg), SUP rats showed impaired performance while CON and DEF rats were unaffected. In contrast, when switched to a choline-supplemented diet (5.0 g/kg), DEF rats' performance was significantly impaired while CON and SUP rats were less affected. These changes in performance were reversible when the rats were switched back to a control diet. In a second experiment, DEF, CON, and SUP rats were either maintained on a control diet, or the choline-supplemented diet. After 12 weeks, DEF rats were significantly impaired by choline supplementation on a matching-to-place water-maze task, which was also accompanied by a decrease in dentate cell proliferation in DEF rats only. IGF-1 levels were elevated by both prenatal and adult choline supplementation. Taken together, these findings suggest that the in utero availability of an essential nutrient, choline, causes differential behavioral and neuroplastic sensitivity to the adult choline supply. PMID:18778697

  10. Uptake and degradation of natural surfactant by isolated rat granular pneumocytes

    SciTech Connect

    Fisher, A.B.; Chander, A.; Reicherter, J. )

    1987-12-01

    It has been previously shown that isolated granular pneumocytes internalize and degrade dipalmitoylphosphatidylcholine (DPPC) in synthetic lipid vesicles and reutilize degradation products for phosphatidylcholine (PC) synthesis. In this study, the authors evaluated the uptake and degradation of radiolabeled natural surfactant (NS) isolated from lung lavage after perfusing isolated rat lungs with ({sup 3}H)choline. Uptake of NS by isolated granular pneumocytes was increased approximately fourfold compared with synthetic liposomes, suggesting that physical form or a component (e.g., a protein) of NS plays a role in phospholipid uptake by these cells. Uptake was significantly decreased by metabolic inhibitors, indicating an energy requirement for this process. After 2-h incubation, the pattern of radioactivity in cells compared with NS showed a significant decrease in PC and DSPC and increase in free choline, choline phosphate, and CDP-choline. This pattern of metabolism indicates degradation of PC and metabolic reutilization of products. These studies support the hypothesis that alveolar phospholipids are accumulated and reutilized by granular pneumocytes for surfactant synthesis.

  11. Special Report: Affinity Chromatography.

    ERIC Educational Resources Information Center

    Parikh, Indu; Cuatrecasas, Pedro

    1985-01-01

    Describes the nature of affinity chromatography and its use in purifying enzymes, studying cell interactions, exploring hormone receptors, and other areas. The potential the technique may have in treating disease is also considered. (JN)

  12. Indirect electrocatalytic determination of choline by monitoring hydrogen peroxide at the choline oxidase-prussian blue modified iron phosphate nanostructures.

    PubMed

    Zhang, Hui; Yin, Yajing; Wu, Ping; Cai, Chenxin

    2012-01-15

    Choline, as a marker of cholinergic activity in brain tissue, is very important in biological and clinical analysis, especially in the clinical detection of the neurodegenerative disorders disease. This work presents an electrochemical approach for the detection of choline based on prussian blue modified iron phosphate nanostructures (PB-FePO(4)). The obtained nanostructures showed a good catalysis toward the electroreduction of H(2)O(2), and an amperometric choline biosensor was developed by immobilizing choline oxidase on the PB-FePO(4) nanostructures. The biosensor exhibited a rapid response (ca. 2s), low detection limit (0.4±0.05 μM), wide linear range (2 μM to 3.2 mM), high sensitivity (~75.2 μAm M(-1) cm(-2)), as well as good stability and repeatability. In addition, the common interfering species, such as ascorbic acid, uric acid and 4-acetamidophenol did not cause obvious interference due to the low detection potential (-0.05 V versus saturated calomel electrode). This nanostructure could be used as a promise platform for the construction of other oxidase-based biosensors. PMID:22119562

  13. Dysregulated choline metabolism in T-cell lymphoma: role of choline kinase-α and therapeutic targeting

    PubMed Central

    Xiong, J; Bian, J; Wang, L; Zhou, J-Y; Wang, Y; Zhao, Y; Wu, L-L; Hu, J-J; Li, B; Chen, S-J; Yan, C; Zhao, W-L

    2015-01-01

    Cancer cells have distinct metabolomic profile. Metabolic enzymes regulate key oncogenic signaling pathways and have an essential role on tumor progression. Here, serum metabolomic analysis was performed in 45 patients with T-cell lymphoma (TCL) and 50 healthy volunteers. The results showed that dysregulation of choline metabolism occurred in TCL and was related to tumor cell overexpression of choline kinase-α (Chokα). In T-lymphoma cells, pharmacological and molecular silencing of Chokα significantly decreased Ras-GTP activity, AKT and ERK phosphorylation and MYC oncoprotein expression, leading to restoration of choline metabolites and induction of tumor cell apoptosis/necropotosis. In a T-lymphoma xenograft murine model, Chokα inhibitor CK37 remarkably retarded tumor growth, suppressed Ras-AKT/ERK signaling, increased lysophosphatidylcholine levels and induced in situ cell apoptosis/necropotosis. Collectively, as a regulatory gene of aberrant choline metabolism, Chokα possessed oncogenic activity and could be a potential therapeutic target in TCL, as well as other hematological malignancies with interrupted Ras signaling pathways. PMID:25768400

  14. Importance of choline as essential nutrient and its role in prevention of various toxicities.

    PubMed

    Biswas, Somava; Giri, Sarbani

    2015-01-01

    Choline is a water-soluble essential nutrient included as a member of the vitamin B12 group owing to its structural similarities with that of the other members of the group. Its roles and functions, however, extend much wider than that of the vitamins with which it is grouped. Choline is vital for maintenance of various key metabolic processes which play a role in the prevention or progression of various health impairments. The occurrence of diseases like neural tube defect (NTD) and Alzheimer's is prevented by the metabolic role of choline. It is also indispensable for mitigation of various forms of toxic contamination. While adequate level of choline in the body is essential, an excess of choline can result in various forms of disorder. To maintain the optimal level of choline in the body can be a challenge. The vital roles played by choline together with the range of contradictions and problems that choline presents make choline an interesting area of study. This paper attempts to summarize and review some recent publications on choline that have opened up new prospect in understanding the multiple role played by choline and in throwing light on the role played by this wonder essential nutrient in mitigating various forms of toxic contamination. PMID:25923965

  15. Nano interfaced biosensor for detection of choline in triple negative breast cancer cells.

    PubMed

    Thiagarajan, Vignesh; Madhurantakam, Sasya; Sethuraman, Swaminathan; Balaguru Rayappan, John Bosco; Maheswari Krishnan, Uma

    2016-01-15

    Choline, a type of Vitamin B, is an important nutrient in the human body and is involved in key metabolic pathways. Abnormal levels of choline leads to diseased conditions. The levels of choline and its associated compounds are found to be elevated in triple negative breast cancer (TNBC) patients. The choline level ranges from 0.4 to 4.9mmol/kg in TNBC. Thus the detection of choline levels in cells can aid in diagnosing breast cancer. The present work aims to develop a nano-interfaced electrochemical biosensor for the rapid detection of choline in cancer cells. For electrochemical detection, glassy carbon electrode coated with a zinc oxide nano-interface was used as the working electrode. Zinc oxide synthesized by hydrothermal method was characterized using SEM and XRD. The choline oxidase (ChOx) enzyme was immobilized on the nano-interface by drop-casting. Choline oxidase (ChOx) converts choline to betaine and H2O2 in the presence of oxygen. The H2O2 produced was determined amperometrically. The amount of H2O2 produced is directly proportional to concentration of choline present. The sensitivity, selectivity, stability and concentration studies were carried out and quantification of choline in TNBC was also carried out. The results demonstrate that this biosensor has the potential to be developed as a clinical tool for breast cancer detection. PMID:26476202

  16. Speciation of copper(II) complexes in an ionic liquid based on choline chloride and in choline chloride/water mixtures.

    PubMed

    De Vreese, Peter; Brooks, Neil R; Van Hecke, Kristof; Van Meervelt, Luc; Matthijs, Edward; Binnemans, Koen; Van Deun, Rik

    2012-05-01

    A deep-eutectic solvent with the properties of an ionic liquid is formed when choline chloride is mixed with copper(II) chloride dihydrate in a 1:2 molar ratio. EXAFS and UV-vis-near-IR optical absorption spectroscopy have been used to compare the coordination sphere of the cupric ion in this ionic liquid with that of the cupric ion in solutions of 0.1 M of CuCl(2)·2H(2)O in solvents with varying molar ratios of choline chloride and water. The EXAFS data show that species with three chloride ions and one water molecule coordinated to the cupric ion as well as species with two chloride molecules and two water molecules coordinated to the cupric ion are present in the ionic liquid. On the other hand, a fully hydrated copper(II) ion is formed in an aqueous solution free of choline chloride, and the tetrachlorocuprate(II) complex forms in aqueous choline chloride solutions with more than 50 wt % of choline chloride. In solutions with between 0 and 50 wt % of choline chloride, mixed chloro-aquo complexes occur. Upon standing at room temperature, crystals of CuCl(2)·2H(2)O and of Cu(choline)Cl(3) formed in the ionic liquid. Cu(choline)Cl(3) is the first example of a choline cation coordinating to a transition-metal ion. Crystals of [choline](3)[CuCl(4)][Cl] and of [choline](4)[Cu(4)Cl(10)O] were also synthesized from molecular or ionic liquid solvents, and their crystal structures were determined. PMID:22524435

  17. Dioctanoylglycerol stimulates accumulation of [methyl-14C]choline and its incorporation into acetylcholine and phosphatidylcholine in a human cholinergic neuroblastoma cell line

    NASA Technical Reports Server (NTRS)

    Slack, B. E.; Richardson, U. I.; Nitsch, R. M.; Wurtman, R. J.

    1992-01-01

    Dioctanoylglycerol, a synthetic diacylglycerol, stimulated [14C]choline uptake in cultured human neuroblastoma (LA-N-2) cells. As this effect has not, to our knowledge, been reported before, it was of interest to characterize it in more detail. In the presence of 500 microM dioctanoylglycerol the levels of [14C]choline attained during a 2 hour labeling period were elevated by 78 +/- 12%, while [14C]acetylcholine and long fatty acyl chain [14C]phosphatidylcholine levels increased by 26 +/- 2% and 19 +/- 5%, respectively (mean +/- S.E.M.). Total (long chain plus dioctanoyl-) [14C]phosphatidylcholine was increased by 198 +/- 33%. Kinetic analysis showed that dioctanoylglycerol reduced the apparent Km for choline uptake to 56 +/- 9% of control (n = 4). The Vmax was not significantly altered. The stimulation of [14C]choline accumulation by dioctanoylglycerol was not dependent on protein kinase C activation; the effect was not mimicked by phorbol ester or by 1-oleoyl-2-acetylglycerol, and was not inhibited by the protein kinase C inhibitors H-7 or staurosporine, or by prolonged pretreatment with phorbol 12-myristate 13-acetate. The effect of dioctanoylglycerol was slightly (but not significantly) reduced by EGTA and strongly inhibited by the cell-permeant calcium chelator bis(o-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid, tetra(acetoxymethyl)ester. Although these results implicate elevated intracellular calcium in the response, dioctanoylglycerol did not increase phosphatidylinositol hydrolysis in LA-N-2 cells, and its effect was not inhibited by the diacylglycerol kinase inhibitor R 59 022 (which blocks the conversion of diacylglycerol to phosphatidic acid, a known stimulator of phosphatidylinositol hydrolysis).(ABSTRACT TRUNCATED AT 250 WORDS).

  18. Concentrations of choline-containing compounds and betaine in common foods.

    PubMed

    Zeisel, Steven H; Mar, Mei-Heng; Howe, Juliette C; Holden, Joanne M

    2003-05-01

    Choline is important for normal membrane function, acetylcholine synthesis and methyl group metabolism; the choline requirement for humans is 550 mg/d for men (Adequate Intake). Betaine, a choline derivative, is important because of its role in the donation of methyl groups to homocysteine to form methionine. In tissues and foods, there are multiple choline compounds that contribute to total choline concentration (choline, glycerophosphocholine, phosphocholine, phosphatidylcholine and sphingomyelin). In this study, we collected representative food samples and analyzed the choline concentration of 145 common foods using liquid chromatography-mass spectrometry. Foods with the highest total choline concentration (mg/100 g) were: beef liver (418), chicken liver (290), eggs (251), wheat germ (152), bacon (125), dried soybeans (116) and pork (103). The foods with the highest betaine concentration (mg/100 g) were: wheat bran (1339), wheat germ (1241), spinach (645), pretzels (237), shrimp (218) and wheat bread (201). A number of epidemiologic studies have examined the relationship between dietary folic acid and cancer or heart disease. It may be helpful to also consider choline intake as a confounding factor because folate and choline methyl donation can be interchangeable. PMID:12730414

  19. Structure and biological function of ENPP6, a choline-specific glycerophosphodiester-phosphodiesterase

    PubMed Central

    Morita, Junko; Kano, Kuniyuki; Kato, Kazuki; Takita, Hiroyuki; Sakagami, Hideki; Yamamoto, Yasuo; Mihara, Emiko; Ueda, Hirofumi; Sato, Takanao; Tokuyama, Hidetoshi; Arai, Hiroyuki; Asou, Hiroaki; Takagi, Junichi; Ishitani, Ryuichiro; Nishimasu, Hiroshi; Nureki, Osamu; Aoki, Junken

    2016-01-01

    Choline is an essential nutrient for all living cells and is produced extracellularly by sequential degradation of phosphatidylcholine (PC). However, little is known about how choline is produced extracellularly. Here, we report that ENPP6, a choline-specific phosphodiesterase, hydrolyzes glycerophosphocholine (GPC), a degradation product of PC, as a physiological substrate and participates in choline metabolism. ENPP6 is highly expressed in liver sinusoidal endothelial cells and developing oligodendrocytes, which actively incorporate choline and synthesize PC. ENPP6-deficient mice exhibited fatty liver and hypomyelination, well known choline-deficient phenotypes. The choline moiety of GPC was incorporated into PC in an ENPP6-dependent manner both in vivo and in vitro. The crystal structure of ENPP6 in complex with phosphocholine revealed that the choline moiety of the phosphocholine is recognized by a choline-binding pocket formed by conserved aromatic and acidic residues. The present study provides the molecular basis for ENPP6-mediated choline metabolism at atomic, cellular and tissue levels. PMID:26888014

  20. Metabolomic profiling can predict which humans will develop liver dysfunction when deprived of dietary choline

    PubMed Central

    Sha, Wei; da Costa, Kerry-Ann; Fischer, Leslie M.; Milburn, Michael V.; Lawton, Kay A.; Berger, Alvin; Jia, Wei; Zeisel, Steven H.

    2010-01-01

    Choline is an essential nutrient, and deficiency causes liver and muscle dysfunction. Common genetic variations alter the risk of developing organ dysfunction when choline deficient, probably by causing metabolic inefficiencies that should be detectable even while ingesting a normal choline-adequate diet. We determined whether metabolomic profiling of plasma at baseline could predict whether humans will develop liver dysfunction when deprived of dietary choline. Fifty-three participants were fed a diet containing 550 mg choline/70 kg/d for 10 d and then fed <50 mg choline/70 kg/d for up to 42 d. Participants who developed organ dysfunction on this diet were repleted with a choline-adequate diet for ≥3 d. Plasma samples, obtained at baseline, end of depletion, and end of repletion, were used for targeted and nontargeted metabolomic profiling. Liver fat was assessed using magnetic resonance spectroscopy. Metabolomic profiling and targeted biochemical analyses were highly correlated for the analytes assessed by both procedures. In addition, we report relative concentration changes of other small molecules detected by the nontargeted metabolomic analysis after choline depletion. Finally, we show that metabolomic profiles of participants when they were consuming a control baseline diet could predict whether they would develop liver dysfunction when deprived of dietary choline.—Sha, W., da Costa, K., Fischer, L. M., Milburn, M. V., Lawton, K. A., Berger, A., Jia, W., Zeisel, S. H. Metabolomic profiling can predict which humans will develop liver dysfunction when deprived of dietary choline. PMID:20371621

  1. Influence of dietary protein and excess methionine on choline needs for young bobwhite quail

    USGS Publications Warehouse

    Serafin, J.A.

    1982-01-01

    Experiments were conducted with young Bobwhite quail (Colinus virginianus) to investigate the effect of differing dietary protein levels and nondetrimental amounts of excess methionine on choline needs. Growth and feed consumption of quail fed an adequate (27.3%) protein purified diet supplemented with 2000 mg/kg of choline were unaffected by increasing the level of excess methionine to 1.75%; however, greater amounts (2.0%, 2.25%) of excess methionine depressed growth (P less than .01), reduced feed consumption (P less than .01), and decreased feed utilization (P less than .05). Quail fed a purified diet containing 13.85% protein and 515 mg/kg of choline grew poorly. Growth was unaffected by additional choline in this diet. Growth was suboptimal among quail fed purified diets containing adequate or high (41.55%) levels of protein in which choline was limiting; however, a high level of protein did not in itself affect performance. Growth was improved by supplemental choline in these diets. Growth of quail fed purified diets with up to 1.35% excess methionine which were limiting (531 mg/kg) in choline was less than that of groups fed 2000 mg/kg of added dietary choline (P less than .01); however, excess methionine did not significantly influence growth of quail fed choline-deficient diets. These experiments indicate that neither high dietary protein nor excess methionine, fed at non-growth-depressing levels, increases dietary choline needs for young Bobwhite quail.

  2. Effects of chronic manipulations of dietary choline on dynamic behavioural situations.

    PubMed

    Fundarò, A; Garassino, G; Molinengo, L

    1987-01-01

    1. The modifications in rat behaviour caused by chronic manipulations of dietary choline were studied in two schedules of operant conditioning. Adult rats were maintained on choline-deficient, low-choline and high-choline enriched diets. 2. In the "periodic conditioning" test, the schedule of reinforcement was changed from a fixed ratio to a fixed interval schedule. In the "reversal" test the contingency for food delivery was switched four times from one lever to the other in a two lever Skinner box. 3. In the "periodic conditioning" test, control and treated groups showed the same reduction of responses/reinforcement from the beginning to the end of trial. The time-course reduction of responses/reinforcement became significant in the high-choline (331 mg/kg/day) and deficient-choline groups earlier than in the low-choline (75 mg/kg/day) enriched and control groups. 4. In the "reversal" test, the low-choline (110 mg/kg/day) enriched diet improved the reinforced responses in the IV reversal; the high-choline (330 mg/kg/day) diet gave a significant impairment of the reinforced responses in the III and IV reversals. The deficient-choline diet caused a reduced number of the total responses and a worsening of the reinforced responses in the II, III and IV reversals. PMID:3423269

  3. AtKuP1: a dual-affinity K+ transporter from Arabidopsis.

    PubMed Central

    Fu, H H; Luan, S

    1998-01-01

    Plant roots contain both high- and low-affinity transport systems for uptake of K+ from the soil. In this study, we characterize a K+ transporter that functions in both high- and low-affinity uptake. Using yeast complementation analysis, we isolated a cDNA for a functional K+ transporter from Arabidopsis (referred to as AtKUP1 for Arabidopsis thaliana K+ uptake). When expressed in a yeast mutant, AtKUP1 dramatically increased K+ uptake capacity at both a low and high [K+] range. Kinetic analyses showed that AtKUP1-mediated K+ uptake displays a "biphasic" pattern similar to that observed in plant roots. The transition from the high-affinity phase (K(m) of 44 microM) to the low-affinity phase (K(m) of 11 mM) occurred at 100 to 200 microM external K+. Both low- and high-affinity K+ uptake via AtKUP1 were inhibited by 5 mM or higher concentrations of NaCl. In addition, AtKUP1-mediated K+ uptake was inhibited by K+ channel blockers, including tetraethylammonium, Cs+, and Ba2+. Consistent with a possible function in K+ uptake from the soil, the AtKUP1 gene is primarily expressed in roots. We conclude that the AtKUP1 gene product may function as a K+ transporter in Arabidopsis roots over a broad range of [K+] in the soil. PMID:9477572

  4. Legionella dumoffii utilizes exogenous choline for phosphatidylcholine synthesis.

    PubMed

    Palusinska-Szysz, Marta; Szuster-Ciesielska, Agnieszka; Kania, Magdalena; Janczarek, Monika; Chmiel, Elżbieta; Danikiewicz, Witold

    2014-01-01

    Phosphatidycholine (PC) is the major membrane-forming phospholipid in eukaryotes but it has been found in only a limited number of prokaryotes. Bacteria synthesize PC via the phospholipid N-methylation pathway (Pmt) or via the phosphatidylcholine synthase pathway (Pcs) or both. Here, we demonstrated that Legionella dumoffii has the ability to utilize exogenous choline for phosphatidylcholine (PC) synthesis when bacteria grow in the presence of choline. The Pcs seems to be a primary pathway for synthesis of this phospholipid in L. dumoffii. Structurally different PC species were distributed in the outer and inner membranes. As shown by the LC/ESI-MS analyses, PC15:0/15:0, PC16:0/15:0, and PC17:0/17:1 were identified in the outer membrane and PC14:0/16:0, PC16:0/17:1, and PC20:0/15:0 in the inner membrane. L. dumoffii pcsA gene encoding phosphatidylcholine synthase revealed the highest sequence identity to pcsA of L. bozemanae (82%) and L. longbeachae (81%) and lower identity to pcsA of L. drancourtii (78%) and L. pneumophila (71%). The level of TNF-α in THP1-differentiated cells induced by live and temperature-killed L. dumoffii cultured on a medium supplemented with choline was assessed. Live L. dumoffii bacteria cultured on the choline-supplemented medium induced TNF-α three-fold less efficiently than cells grown on the non-supplemented medium. There is an evident effect of PC modification, which impairs the macrophage inflammatory response. PMID:24821544

  5. Legionella dumoffii Utilizes Exogenous Choline for Phosphatidylcholine Synthesis

    PubMed Central

    Palusinska-Szysz, Marta; Szuster-Ciesielska, Agnieszka; Kania, Magdalena; Janczarek, Monika; Chmiel, Elżbieta; Danikiewicz, Witold

    2014-01-01

    Phosphatidycholine (PC) is the major membrane-forming phospholipid in eukaryotes but it has been found in only a limited number of prokaryotes. Bacteria synthesize PC via the phospholipid N-methylation pathway (Pmt) or via the phosphatidylcholine synthase pathway (Pcs) or both. Here, we demonstrated that Legionella dumoffii has the ability to utilize exogenous choline for phosphatidylcholine (PC) synthesis when bacteria grow in the presence of choline. The Pcs seems to be a primary pathway for synthesis of this phospholipid in L. dumoffii. Structurally different PC species were distributed in the outer and inner membranes. As shown by the LC/ESI-MS analyses, PC15:0/15:0, PC16:0/15:0, and PC17:0/17:1 were identified in the outer membrane and PC14:0/16:0, PC16:0/17:1, and PC20:0/15:0 in the inner membrane. L. dumoffii pcsA gene encoding phosphatidylcholine synthase revealed the highest sequence identity to pcsA of L. bozemanae (82%) and L. longbeachae (81%) and lower identity to pcsA of L. drancourtii (78%) and L. pneumophila (71%). The level of TNF-α in THP1-differentiated cells induced by live and temperature-killed L. dumoffii cultured on a medium supplemented with choline was assessed. Live L. dumoffii bacteria cultured on the choline-supplemented medium induced TNF-α three-fold less efficiently than cells grown on the non-supplemented medium. There is an evident effect of PC modification, which impairs the macrophage inflammatory response. PMID:24821544

  6. Lecithin and choline in human health and disease.

    PubMed

    Canty, D J; Zeisel, S H

    1994-10-01

    Choline is involved in methyl group metabolism and lipid transport and is a component of a number of important biological compounds including the membrane phospholipids lecithin, sphingomyelin, and plasmalogen; the neurotransmitter acetylcholine; and platelet activating factor. Although a required nutrient for several animal species, choline is not currently designated as essential for humans. However, recent clinical studies show it to be essential for normal liver function. Additionally, a large body of evidence from the fields of molecular and cell biology shows that certain phospholipids play a critical role in generating second messengers for cell membrane signal transduction. This process involves a cascade of reactions that translate an external cell stimulus such as a hormone or growth factor into a change in cell transport, metabolism, growth, function, or gene expression. Disruptions in phospholipid metabolism can interfere with this process and may underlie certain disease states such as cancer and Alzheimer's disease. These recent findings may be appropriate in the consideration of choline as an essential nutrient for humans. PMID:7816350

  7. Choline phospholipid metabolism: a target in cancer cells?

    PubMed

    Ackerstaff, Ellen; Glunde, Kristine; Bhujwalla, Zaver M

    2003-10-15

    The experience of treating cancer over the past several decades overwhelmingly demonstrates that the disease continues to evade the vast array of drugs and treatment modalities available in the twenty-first century. This is not surprising in view of the complexity of this disease, and the multiplicities of pathways available to the cancer cell to enable its survival. Although the progression of cancer arrives at a common end point of cachexia, organ failure, and death, common pathways are rare in cancer. Identifying and targeting common pathways that would act across these levels of multiplicity is essential for the successful treatment of this disease. Over the past decade, one common characteristic consistently revealed by magnetic resonance spectroscopic studies is the elevation of phosphocholine and total choline-containing compounds in cancer cells and solid tumors. This elevation has been observed in almost every single cancer type studied with NMR spectroscopy and can be used as an endogenous biomarker of cancer. In this article, we have summarized some of the observations on the choline phospholipid metabolism of cancer cells and tumors, and make a case for targeting the aberrant choline phospholipid metabolism of cancer cells. PMID:14523987

  8. The choline-depleted type II pneumonocyte. A model for investigating the synthesis of surfactant lipids.

    PubMed Central

    Anceschi, M M; Di Renzo, G C; Venincasa, M D; Bleasdale, J E

    1984-01-01

    When type II pneumonocytes from adult rats were maintained in a medium that lacked choline, the incorporation of [14C]glycerol into phosphatidylcholine was not greatly diminished during the period that the cells displayed characteristics of type II pneumonocytes. Cells that were maintained in choline-free medium that contained choline oxidase and catalase, however, became depleted of choline and subsequent synthesis of phosphatidylcholine by these cells was responsive to choline in the extracellular medium. Incorporation of [14C]glycerol into phosphatidylcholine by choline-depleted cells was stimulated maximally (approx. 6-fold) by extracellular choline at a concentration (0.05 mM) that also supported the greatest incorporation into phosphatidylglycerol. The incorporation of [14C]glycerol into other glycerophospholipids by choline-depleted cells was not increased by extracellular choline. When cells were incubated in the presence of [3H]cytidine, the choline-dependent stimulation of the synthesis of phosphatidylcholine and phosphatidylglycerol was accompanied by an increased recovery of [3H]CMP. This increased recovery of [3H]CMP reflected an increase in the intracellular amount of CMP from 48 +/- 9 to 76 +/- 16 pmol/10(6) cells. Choline-depleted cells that were exposed to [3H]choline contained [3H]CDP-choline as the principal water-soluble choline derivative. As the extracellular concentration of choline was increase, however, the amount of 3H in phosphocholine greatly exceeded that in all other water-soluble derivatives. Choline-depletion of cells resulted in an increase in the specific activity of CTP:phosphocholine cytidylyltransferase in cell homogenates (from 0.40 +/- 0.15 to 1.31 +/- 0.20 nmol X min-1 X mg of protein-1). These data are indicative that the biosynthesis of phosphatidylcholine is integrated with that of phosphatidylglycerol and are consistent with the proposed involvement of CMP in this integration. The choline-depleted type II pneumonocyte

  9. Molecular cloning of a cDNA for a putative choline co-transporter from Limulus CNS.

    PubMed

    Wang, Y; Cao, Z; Newkirk, R F; Ivy, M T; Townsel, J G

    2001-05-01

    It is well documented that the sodium dependent, hemicholinium-3 sensitive, high affinity choline co-transporter is rate limiting in the biosynthesis of acetylcholine and is essential to cholinergic transmission. Until recently this transporter had eluded cloning. Okuda et al. (2000. Nature Neurosci. 3, 120-125) recently reported the successful cloning of the choline co-transporter in Caenorhabditis elegans (CHO-1) and rat (CHT1). We report herein the cloning of the choline co-transporter in the horseshoe crab, Limulus polyphemus. Through the use of a series of degenerate primers selected from consensus sequences of CHO-1 and CHT1, we generated two probes that were used to search a Limulus cDNA library produced from central nervous system (CNS) tissue. The full length nucleotide sequence of the Limulus homolog consists of 3368 bp which includes an open reading frame (ORF) that predicts a protein of 579 amino acids and two non-translation regions (NTR), one at the 3' end and the other at the 5' end. The amino acid sequence has 46% identity with rat CHT1 and 50% identity with both CHO-1 in C. elegans and the recently cloned human co-transporter (hCHT; Apparsundaram et al., 2000. Biochem. Biophys. Res. Commun. 276, 862-867; Okuda and Haga, 2000. FEBS Lett. 484, 92-97). Hydropathy plot analysis predicts the Limulus choline co-transporter (LChCoT) to have thirteen transmembrane domains (TMD), with the N-terminus oriented extracellularly and the C-terminus oriented intracellularly. Northern blot analyses using cDNA probes designed from LChCoT cDNA sequences revealed its distribution specifically in central nervous system structures. On the other hand it was not found in non-nervous tissues. The successful cloning of LChCoT, which was shown to be a member of the sodium-dependent glucose transporter family (SLGT), should prove useful in the determination of its physiological regulation, including its intracellular trafficking. PMID:11368908

  10. A flower-like nickel oxide nanostructure: synthesis and application for choline sensing.

    PubMed

    Sattarahmady, N; Heli, H; Dehdari Vais, R

    2014-02-01

    Flower-like nickel oxide nanostructure was synthesized by a simple desolvation method. The nanostructure was then employed as the modifier of a carbon paste electrode to fabricate a choline sensor. The mechanism and kinetics of the electrocatalytic oxidation of choline on the modified electrode surface were studied by cyclic voltammetry, steady-state polarization curve, and chronoamperometry. The catalytic rate constant and the charge transfer coefficient of the choline electrooxidation process by an active nickel species, and the diffusion coefficient of choline were reported. An amperometric method was developed for determination of choline with a sensitivity of 60.5 mA mol(-1)Lcm(-2) and a limit of detection of 25.4 μmol L(-1). The sensor had the advantages of high electrocatalytic activity and sensitivity, and long-term stability toward choline, with a simple fabrication method without complications of immobilization steps and using any enzyme or reagent. PMID:24401406

  11. Effects of acute CDP-choline treatment on resting state brain oscillations in healthy volunteers.

    PubMed

    Knott, Verner; de la Salle, Sara; Smith, Dylan; Choueiry, Joelle; Impey, Danielle; Smith, Meaghan; Beaudry, Elise; Saghir, Salman; Ilivitsky, Vadim; Labelle, Alain

    2015-03-30

    CDP-choline (cytidine-5'-diphosphocholine) is a phospholipid used to treat cognitive disorders, presumably repairing and maintaining brain cell membranes. Additional mechanisms may include enhanced cholinergic neurotransmission as the α7 nicotinic receptor actions of choline and increased acetylcholine synthesis accompanying CDP-choline administration may modulate brain oscillations underlying cognitive processes. This study utilizes electroencephalographic (EEG) recordings in healthy volunteers to evaluate CDP-choline induction of an oscillatory response profile associated with nicotinic stimulation. Resting state EEG was acquired in 24 male volunteers administered low (500mg) and moderate (1000mg) doses of CDP-choline in a randomized placebo-controlled, crossover trial. Consistent with nicotinic agonist treatment, spectral analysis showed dose-dependent reductions in delta and increases in alpha oscillations, which were also accompanied by decreases in beta and gamma oscillatory activity. These findings support the posit that CDP-choline cognitive enhancement involves multiple mechanisms including facilitated nicotinic cholinergic action. PMID:25700947

  12. Changes in brain striatum dopamine and acetylcholine receptors induced by chronic CDP-choline treatment of aging mice.

    PubMed Central

    Giménez, R.; Raïch, J.; Aguilar, J.

    1991-01-01

    1. Spiroperidol binding (dopamine D2 receptors) and quinuclidinyl benzilate binding (muscarinic receptors) in striata of 19-month old mice was analyzed for animals that had received chronic administration of cytidine 5'-diphosphocholine (CDP-choline) incorporated into the chow consumed (100 or 500 mg kg-1 added per day) for the 7 months before they were killed. 2. Treated animals displayed an increase in the dopamine receptor densities of 11% for those receiving 100 mg kg-1 and 18% for those receiving 500 mg kg-1 as compared to the control aged animals that had received no CDP-choline. Control animals showed, from 2 months to 19 months of life, a 28% decrease in the receptor density. No change in the affinity of the receptors for spiroperidol was found in the treated or untreated animals. 3. Muscarinic acetylcholine receptor densities were also partially recovered by the same treatment in aged animals that showed a 14% decrease of these receptors in this case. The muscarinic receptor density increased 6% for the animals that received 100 mg kg-1 and 17% for the animals that received 500 mg kg-1 without any change in the affinity of the receptor for quinuclidinyl benzilate. 4. Aged animals displayed a slight increase in brain membrane fluidity as indicated by a decrease in the polarization value of the non-polar fluorophore 1,6-diphenyl-1,3,5-hexatriene. Interestingly, in the treated animals a greater increase in membrane fluidity was determined and found to be very similar for the two doses.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1839138

  13. Sex and menopausal status influence human dietary requirements for the nutrient choline2

    PubMed Central

    Fischer, Leslie M; daCosta, Kerry Ann; Kwock, Lester; Stewart, Paul W; Lu, Tsui-Shan; Stabler, Sally P; Allen, Robert H; Zeisel, Steven H

    2008-01-01

    Background Although humans require dietary choline for methyl donation, membrane function, and neurotransmission, choline can also be derived from the de novo synthesis of phosphatidylcholine, which is up-regulated by estrogen. A recommended Adequate Intake (AI) exists for choline; however, an Estimated Average Requirement has not been set because of a lack of sufficient human data. Objective The objective of the study was to evaluate the dietary requirements for choline in healthy men and women and to investigate the clinical sequelae of choline deficiency. Design Fifty-seven adult subjects (26 men, 16 premenopausal women, 15 postmenopausal women) were fed a diet containing 550 mg choline · 70 kg−1 · d−1 for 10 d followed by <50 mg choline · 70 kg−1 · d−1 with or without a folic acid supplement (400 μg/d per randomization) for up to 42 d. Subjects who developed organ dysfunction during this diet had normal organ function restored after incremental amounts of choline were added back to the diet. Blood and urine were monitored for signs of toxicity and metabolite concentrations, and liver fat was assessed by using magnetic resonance imaging. Results When deprived of dietary choline, 77% of men and 80% of postmenopausal women developed fatty liver or muscle damage, whereas only 44% of premenopausal women developed such signs of organ dysfunction. Moreover, 6 men developed these signs while consuming 550 mg choline · 70 kg−1 · d−1, the AI for choline. Folic acid supplementation did not alter the subjects’ response. Conclusion Subject characteristics (eg, menopausal status) modulated the dietary requirement for choline, and a daily intake at the current AI was not sufficient to prevent organ dysfunction in 19 of the subjects. PMID:17490963

  14. Common genetic polymorphisms affect the human requirement for the nutrient choline

    PubMed Central

    da Costa, Kerry-Ann; Kozyreva, Olga G.; Song, Jiannan; Galanko, Joseph A.; Fischer, Leslie M.; Zeisel, Steven H.

    2006-01-01

    Humans eating diets deficient in the essential nutrient choline can develop organ dysfunction. We hypothesized that common single nucleotide polymorphisms (SNPs) in genes involved in choline metabolism influence the dietary requirement of this nutrient. Fifty-seven humans were fed a low choline diet until they developed organ dysfunction or for up to 42 days. We tested DNA SNPs for allelic association with susceptibility to developing organ dysfunction associated with choline deficiency. We identified an SNP in the promoter region of the phosphatidylethanolamine N-methyltransferase gene (PEMT; −744 G→C; rs12325817) for which 18 of 23 carriers of the C allele (78%) developed organ dysfunction when fed a low choline diet (odds ratio 25, P=0.002). The first of two SNPs in the coding region of the choline dehydrogenase gene (CHDH; +318 A→C; rs9001) had a protective effect on susceptibility to choline deficiency, while a second CHDH variant (+432 G→T; rs12676) was associated with increased susceptibility to choline deficiency. A SNP in the PEMT coding region (+5465 G→A; rs7946) and a betaine:homocysteine methyl-transferase (BHMT) SNP (+742 G→A; rs3733890) were not associated with susceptibility to choline deficiency. Identification of common polymorphisms that affect dietary requirements for choline could enable us to identify individuals for whom we need to assure adequate dietary choline intake.—da Costa, K.-A., Kozyreva, O. G., Song, J., Galanko, J. A., Fischer, L. M., Zeisel, S. H. Common genetic polymorphisms affect the human requirement for the nutrient choline. PMID:16816108

  15. Choline is required in the diet of lactating dams to maintain maternal immune function.

    PubMed

    Dellschaft, Neele S; Ruth, Megan R; Goruk, Susan; Lewis, Erin D; Richard, Caroline; Jacobs, René L; Curtis, Jonathan M; Field, Catherine J

    2015-06-14

    Choline demands during lactation are high; however, detailed knowledge is lacking regarding the optimal dietary intake during this critical period. The present study was designed to determine the effects of varying intakes of choline on maternal immune function during lactation. Primiparous Sprague-Dawley rats (n 42) were randomised 24-48 h before birth and fed the following diets for 21 d: choline-devoid (0 g choline/kg diet; D, n 10); 1·0 g choline/kg diet (C1, n 11); 2·5 g choline/kg diet (C2·5, n 10); 6·2 g choline/kg diet (C6, n 11). Splenocytes were isolated and stimulated ex vivo with concanavalin A, lipopolysaccharide (LPS) or CD3/CD28. D and C6 dams had lower final body weight, spleen weight and average pup weight than C1 dams (P< 0·05). There was a linear relationship between free choline concentration in pup stomach contents with maternal dietary choline content (P< 0·001, r² 0·415). Compared with C1 and C2·5, D spleens had a lower proportion of mature T cells and activated suppressor cells, and this resulted in reduced cytokine production after stimulation (P< 0·05). Feeding 6·2 g choline/kg diet resulted in a higher cytokine production after stimulation with CD3/CD28 (P< 0·05). Except for a higher IL-6 production after LPS stimulation with cells from the C2·5 dams (P< 0·05), there were no differences between the C1 and C2·5 dams. For the first time, we show that feeding lactating mothers a diet free of choline has substantial effects on their immune function and on offspring growth. Additionally, excess dietary choline had adverse effects on maternal and offspring body weight but only minimal effects on maternal immune function. PMID:25902853

  16. Characterization of xylose uptake in the yeasts Pichia heedii and Pichia stipitis

    SciTech Connect

    Does, A.L.; Bisson, L.F. )

    1989-01-01

    The efficient conversion of renewable biomass to ethanol is an area of active research. Pentoses make up nearly one-third of the reducing sugars derived from the hydrolysis of lignocellulose, with xylose as the major component. The kinetics of xylose uptake were investigated in the efficient xylose fermenter Pichia stipitis and in the more readily genetically manipulated, strictly respiratory yeast Pichia heedii. Both yeasts demonstrated more than one xylose uptake system, differing in substrate affinity. The K{sub m} of high-affinity xylose uptake in both organisms was similar to that of the efficient high-affinity glucose uptake system of Saccharomyces cerevisiae. In P. heedii, low-affinity xylose uptake was enhanced with growth on 2% but not 0.05% xylose and high-affinity uptake was reduced. In contrast to glucose uptake, xylose uptake in P. heedii was inhibited by dinitrophenol. Dinitrophenol inhibited both glucose and xylose uptake by P. stipitis. Glucose uptake was not inhibited by a 100-fold molar excess of xylose in P. heedii. It is suggested that xylose uptake in P. heedii is via a carrier system(s) distinct from those for glucose uptake.

  17. Organic and inorganic nitrogen uptake in lichens.

    PubMed

    Dahlman, Lena; Persson, Jörgen; Palmqvist, Kristin; Näsholm, Torgny

    2004-07-01

    In order to learn more about nitrogen (N) acquisition in lichens, and to see whether different lichens differ in their affinity to various N sources, N uptake was measured in 14 various lichen associations ("species"). These species represented various morphologies (fruticose or foliose), contrasting microhabitat preferences (epiphytic or terricolous), and had green algal, cyanobacterial or both forms of photobionts. N was supplied under non-limiting conditions as an amino acid mixture, ammonium, or nitrate, using 15N to quantify uptake. Carbonyl cyanide m-chlorophenylhydrazone (CCCP) was used to separate active and passive uptake. Thallus N, amino acids, soluble polyol concentrations, and the biont-specific markers chlorophyll a and ergosterol were quantified, aiming to test if these metabolites or markers were correlated with N uptake capacity. Ammonium uptake was significantly greater and to a higher extent passive, relative to the other two N sources. Nitrate uptake differed among lichen photobiont groups, cyanobacterial lichens having a lower uptake rate. All lichens had the capacity to assimilate amino acids, in many species at rates equal to nitrate uptake or even higher, suggesting that organic N compounds could potentially have an important role in the N nutrition of these organisms. There were no clear correlations between N uptake rates and any of the measured metabolites or markers. The relative uptake rates of ammonium, nitrate and amino acids were not related to morphology or microhabitat. PMID:15060826

  18. Polyamine Uptake in Carrot Cell Cultures 1

    PubMed Central

    Pistocchi, Rossella; Bagni, Nello; Creus, José A.

    1987-01-01

    Putrescine and spermidine uptake into carrot (Daucus carota L.) cells in culture was studied. The time course of uptake showed that the two polyamines were very quickly transported into the cells, reaching a maximum absorption within 1 minute. Increasing external polyamine concentrations up to 100 millimolar showed the existence of a biphasic system with different affinities at low and high polyamine concentrations. The cellular localization of absorbed polyamines was such that a greater amount of putrescine was present in the cytoplasmic soluble fraction, while spermidine was mostly present in cell walls. The absorbed polyamines were released into the medium in the presence of increasing external concentrations of the corresponding polyamine or Ca2+. The effects of Ca2+ were different for putrescine and spermidine; putrescine uptake was slightly stimulated by 10 micromolar Ca2+ and inhibited by higher concentrations, while for spermidine uptake there was an increasing stimulation in the Ca2+ concentration range between 10 micromolar and 1 millimolar. La3+ nullified the stimulatory effect of 10 micromolar Ca2+ on putrescine uptake and that of 1 millimolar Ca2+ on spermidine uptake. La3+ at 0.5 to 1 millimolar markedly inhibited the uptake of both polyamines, suggesting that it interferes with the sites of polyamine uptake. Putrescine uptake was affected to a lesser extent by metabolic inhibitors than was spermidine uptake. It is proposed that the entry of polyamines into the cells is driven by the transmembrane electrical gradient, with a possible antiport mechanism between external and internal polyamine molecule. PMID:16665446

  19. Utilization of choline from crude soybean lecithin by chicks. 1. Growth and prevention of perosis.

    PubMed

    Lipstein, B; Bornstein, S; Budowski, P

    1977-01-01

    Data obtained with growing chicks fed a semi-purified diet indicate that choline from crude soybean lecithin is as well utilized as synthetic choline chloride, on the basis of growth, relative liver weight and prevention of perosis. Extrapolation of the results on growth and perosis prevention, obtained between 1 and 3 weeks of age, to performance on practical-type diets yields choline requirements for broiler-type chicks ranging from 800 to 1000 mg./kg. diet (as choline chloride). The requirement seems to decrease with age. PMID:564504

  20. Phospholipid biosynthesis in Candida albicans: Regulation by the precursors inositol and choline

    SciTech Connect

    Klig, L.S.; Friedli, L.; Schmid, E. )

    1990-08-01

    Phospholipid metabolism in the pathogenic fungus Candida albicans was examined. The phospholipid biosynthetic pathways of C. albicans were elucidated and were shown to be similar to those of Saccharomyces cerevisiae. However, marked differences were seen between these two fungi in the regulation of the pathways in response to exogenously provided precursors inositol and choline. In S. cerevisiae, the biosynthesis of phosphatidylcholine via methylation of phosphatidylethanolamine appears to be regulated in response to inositol and choline; provision of choline alone does not repress the activity of this pathway. The same pathway in C. albicans responds to the exogenous provision of choline. Possible explanations for the observed differences in regulation are discussed.

  1. Exogenous fatty acids affect CDP-choline pathway to increase phosphatidylcholine synthesis in granular pneumocytes

    SciTech Connect

    Chander, A.; Gullo, J.; Reicherter, J.; Fisher, A.

    1987-05-01

    Regulation of phosphatidylcholine (PC) synthesis in rat granular pneumocytes isolated by tryptic digestion of lungs and maintained in primary culture for 24 h was investigated by following effects of exogenous fatty acids on (/sup 3/H-methyl)choline incorporation into PC and disaturated PC (DSPC). At 0.1 mM choline, the rate of choline incorporation into PC and DSPC was 440 +/- and 380 +/- 50 pmol/h/ug Pi (mean +/- SE, n=3-5), respectively, and was linear for up to 3 h. PC synthesis was significantly increased by 0.1 mM each of palmitic, oleic, linoleic, or linolenic acid. However, synthesis of DSPC was increased only by palmitic acid and this increase was prevented by addition of oleic acid suggesting lack of effect on the remodeling pathway. Pulse-chase experiments with choline in absence or presence of palmitic or oleic acid showed that the label declined in choline phosphate and increased in PC more rapidly in presence of either of the fatty acids, suggesting rapid conversion of choline phosphate to PC. Microsomal choline phosphate cytidyltransferase activity in cells preincubated without or with palmitic acid for 3 h was 0.81 +/- 0.07 and 1.81 +/- 0.09 nmol choline phosphate converted/min/mg protein (n=4). These results suggest that in granular pneumocytes, exogenous fatty acids modulate PC synthesis by increasing choline phosphate cytidyltransferase activity.

  2. Is There an Additional Value of {sup 11}C-Choline PET-CT to T2-weighted MRI Images in the Localization of Intraprostatic Tumor Nodules?

    SciTech Connect

    Van den Bergh, Laura; Koole, Michel; Isebaert, Sofie; Joniau, Steven; Deroose, Christophe M.; Oyen, Raymond; Lerut, Evelyne; Budiharto, Tom; Mottaghy, Felix; Bormans, Guy; Van Poppel, Hendrik; Haustermans, Karin

    2012-08-01

    Purpose: To investigate the additional value of {sup 11}C-choline positron emission tomography (PET)-computed tomography (CT) to T2-weighted (T2w) magnetic resonance imaging (MRI) for localization of intraprostatic tumor nodules. Methods and Materials: Forty-nine prostate cancer patients underwent T2w MRI and {sup 11}C-choline PET-CT before radical prostatectomy and extended lymphadenectomy. Tumor regions were outlined on the whole-mount histopathology sections and on the T2w MR images. Tumor localization was recorded in the basal, middle, and apical part of the prostate by means of an octant grid. To analyze {sup 11}C-choline PET-CT images, the same grid was used to calculate the standardized uptake values (SUV) per octant, after rigid registration with the T2w MR images for anatomic reference. Results: In total, 1,176 octants were analyzed. Sensitivity, specificity, and accuracy of T2w MRI were 33.5%, 94.6%, and 70.2%, respectively. For {sup 11}C-choline PET-CT, the mean SUV{sub max} of malignant octants was significantly higher than the mean SUV{sub max} of benign octants (3.69 {+-} 1.29 vs. 3.06 {+-} 0.97, p < 0.0001) which was also true for mean SUV{sub mean} values (2.39 {+-} 0.77 vs. 1.94 {+-} 0.61, p < 0.0001). A positive correlation was observed between SUV{sub mean} and absolute tumor volume (Spearman r = 0.3003, p = 0.0362). No correlation was found between SUVs and prostate-specific antigen, T-stage or Gleason score. The highest accuracy (61.1%) was obtained with a SUV{sub max} cutoff of 2.70, resulting in a sensitivity of 77.4% and a specificity of 44.9%. When both modalities were combined (PET-CT or MRI positive), sensitivity levels increased as a function of SUV{sub max} but at the cost of specificity. When only considering suspect octants on {sup 11}C-choline PET-CT (SUV{sub max} {>=} 2.70) and T2w MRI, 84.7% of these segments were in agreement with the gold standard, compared with 80.5% for T2w MRI alone. Conclusions: The additional value of {sup

  3. Characterization of new eye drops with choline salicylate and assessment of their irritancy by in vitro short time exposure tests.

    PubMed

    Wroblewska, Katarzyna; Kucinska, Małgorzata; Murias, Marek; Lulek, Janina

    2015-09-01

    The aim of our study was to examine the irritation potential of new eye drops containing 2% choline salicylate (CS) as an active pharmaceutical ingredient (API) and various polymers increasing eye drop viscosity (hydroxyethylcellulose, hydroxypropyl methylcellulose, methylcellulose, polyvinyl alcohol, polyvinylpyrrolidone). The standard method for assessing the potential of irritating substances has been the Draize rabbit eye test. However the European Centre for Validation of Alternative Methods and the Coordinating Committee for Validation of Alternative Methods recommend, short time exposure (STE) in vitro tests as an alternative method for assessing eye irritation. The eye irritation potential was determined using cytotoxicity test methods for rabbit corneal cell line (SIRC) after 5 min exposure. The viability of cells was determined using two cytotoxicity assays: MTT and Neutral Red Uptake. According to the irritation rankings for the short time exposure test, all tested eye drops are classified as non-irritating (cell viability >70%). PMID:27134543

  4. Characterization of new eye drops with choline salicylate and assessment of their irritancy by in vitro short time exposure tests

    PubMed Central

    Wroblewska, Katarzyna; Kucinska, Małgorzata; Murias, Marek; Lulek, Janina

    2014-01-01

    The aim of our study was to examine the irritation potential of new eye drops containing 2% choline salicylate (CS) as an active pharmaceutical ingredient (API) and various polymers increasing eye drop viscosity (hydroxyethylcellulose, hydroxypropyl methylcellulose, methylcellulose, polyvinyl alcohol, polyvinylpyrrolidone). The standard method for assessing the potential of irritating substances has been the Draize rabbit eye test. However the European Centre for Validation of Alternative Methods and the Coordinating Committee for Validation of Alternative Methods recommend, short time exposure (STE) in vitro tests as an alternative method for assessing eye irritation. The eye irritation potential was determined using cytotoxicity test methods for rabbit corneal cell line (SIRC) after 5 min exposure. The viability of cells was determined using two cytotoxicity assays: MTT and Neutral Red Uptake. According to the irritation rankings for the short time exposure test, all tested eye drops are classified as non-irritating (cell viability >70%). PMID:27134543

  5. A sodium-indpendent low affinity transport system for neutral amino acids in rabbit ileal mucosa.

    PubMed Central

    Paterson, J Y; Sepúlveda, F V; Smith, M W

    1980-01-01

    1. The kinetic parameters for serine, alanine and methionine uptake by rabbit ileal mucosa have been determined in the absence of Na. 2. Uptake of all three amino acids took place through a single mediated system. The apparent Km values of serine, alanine and methionine for this system were equal to their respective apparent K1 values (approximately 89, 75 and 23 mM respectively). 3. Autoradiography was used to measure the cellular location of alanine uptake by rabbit ileum. Approximately 80% of the total uptake took place in the upper third of each villus. This uptake was reduced by 75% either by removal of Na or addition of serine. The proportional distribution of Na-dependent and Na-independent alanine uptakes along the villus was found to be equal. 4. The kinetic properties of the low affinity uptake mechanism for neutral amino acids, seen in the absence of Na, were virtually identical with those of one of the uptake mechanisms seen previously in the presence of Na. 5. The low affinity uptake mechanism appears to be Na-independent. It is suggested that the Na-coupled uptake of amino acid takes place through the high affinity system. PMID:7359411

  6. Heparin affinity purification of extracellular vesicles

    PubMed Central

    Balaj, Leonora; Atai, Nadia A.; Chen, Weilin; Mu, Dakai; Tannous, Bakhos A.; Breakefield, Xandra O.; Skog, Johan; Maguire, Casey A.

    2015-01-01

    Extracellular vesicles (EVs) are lipid membrane vesicles released by cells. They carry active biomolecules including DNA, RNA, and protein which can be transferred to recipient cells. Isolation and purification of EVs from culture cell media and biofluids is still a major challenge. The most widely used isolation method is ultracentrifugation (UC) which requires expensive equipment and only partially purifies EVs. Previously we have shown that heparin blocks EV uptake in cells, supporting a direct EV-heparin interaction. Here we show that EVs can be purified from cell culture media and human plasma using ultrafiltration (UF) followed by heparin-affinity beads. UF/heparin-purified EVs from cell culture displayed the EV marker Alix, contained a diverse RNA profile, had lower levels of protein contamination, and were functional at binding to and uptake into cells. RNA yield was similar for EVs isolated by UC. We were able to detect mRNAs in plasma samples with comparable levels to UC samples. In conclusion, we have discovered a simple, scalable, and effective method to purify EVs taking advantage of their heparin affinity. PMID:25988257

  7. Fully automated preparation of [11C]choline and [18F]fluoromethylcholine using TracerLab synthesis modules and facilitated quality control using analytical HPLC.

    PubMed

    Shao, Xia; Hockley, Brian G; Hoareau, Raphaël; Schnau, Paul L; Scott, Peter J H

    2011-02-01

    Modifications of a GE TracerLab FX(C-Pro), which can be implemented for solid-phase [(11)C]methylation are described. The simplified procedure for synthesis of [(11)C]choline uses a single Sep-Pak CM-Light cation-exchange cartridge for both solid-supported reaction and purification. Compared with the commonly used two Sep-Pak method, the low back-pressure of this Sep-Pak enables efficient and reliable production of [(11)C]choline using a TracerLab FX(C-Pro) without requirement for any gas pressure adjustment. Typical radiochemical yields (RCY) are >60%, radiochemical purity (RCP) is 99.9% and levels of residual precursor in the final product, which may inhibit the uptake of [(11)C]choline, are reduced to 1 μg/mL. Similarly, modification of a GE TracerLab FX(FN) is reported which enables gas-phase production of [(18)F]fluoromethylcholine, suitable for pre-clinical use, (in 4-6% RCY and >99.7% RCP) using a related Sep-Pak method. These modifications can be utilized for solid-phase [(11)C]methylation and [(18)F]fluoromethylation of other radiotracers, and allow straightforward switching to other module configurations for solution-phase radiochemistry or loop chemistry. In addition, we report a convenient HPLC ion chromatography method, which can monitor residual precursor and the radiochemical purity of product at the same time, providing highly efficient quality control for routine clinical application. The reported HPLC method is appropriate for analysis of doses of both [(11)C]choline and [(18)F]fluoromethylcholine, and eliminates the need for a GC method to determine residual precursor levels. PMID:21115355

  8. Detection of Local, Regional, and Distant Recurrence in Patients With PSA Relapse After External-Beam Radiotherapy Using {sup 11}C-Choline Positron Emission Tomography

    SciTech Connect

    Breeuwsma, Anthonius J.; Pruim, Jan; Bergh, Alphons C.M. van den; Leliveld, Anna M.; Nijman, Rien J.M.; Dierckx, Rudi A.J.O.; Jong, Igle J. de

    2010-05-01

    Purpose: An elevated serum prostate-specific antigen (PSA) level cannot distinguish between local-regional recurrences and the presence of distant metastases after treatment with curative intent for prostate cancer. With the advent of salvage treatment such as cryotherapy, it has become important to localize the site of recurrence (local or distant). In this study, the potential of {sup 11}C-choline positron emission tomography (PET) to identify site of recurrence was investigated in patients with rising PSA after external-beam radiotherapy (EBRT). Methods and Materials: Seventy patients with histologically proven prostate cancer treated with EBRT and showing biochemical recurrence as defined by American Society for Therapeutic Radiology and Oncology consensus statement and 10 patients without recurrence underwent a PET scan using 400 MBq {sup 11}C-choline intravenously. Biopsy-proven histology from the site of suspicion, findings with other imaging modalities, clinical follow-up and/or response to adjuvant therapy were used as comparative references. Results: None of the 10 patients without biochemical recurrence had a positive PET scan. Fifty-seven of 70 patients with biochemical recurrence (median PSA 9.1 ng/mL; mean PSA 12.3 ng/mL) showed an abnormal uptake pattern (sensitivity 81%). The site of recurrence was only local in 41 of 57 patients (mean PSA 11.1 ng/mL at scan), locoregionally and/or distant in 16 of 57 patients (mean PSA 17.7 ng/mL). Overall the positive predictive value and negative predictive value for {sup 11}C-choline PET scan were 1.0 and 0.44 respectively. Accuracy was 84%. Conclusions: {sup 11}C-choline PET scan is a sensitive technique to identify the site of recurrence in patients with PSA relapse after EBRT for prostate cancer.

  9. Clinical applications of choline PET/CT in brain tumors.

    PubMed

    Giovannini, Elisabetta; Lazzeri, Patrizia; Milano, Amalia; Gaeta, Maria Chiara; Ciarmiello, Andrea

    2015-01-01

    Malignant gliomas and metastatic tumors are the most common forms of brain tumors. From a clinical perspective, neuroimaging plays a significant role, in diagnosis, treatment planning, and follow-up. To date MRI is considered the current clinical gold standard for imaging, however, despite providing superior structural detail it features poor specificity in identifying viable tumors in brain treated with surgery, radiation, or chemotherapy. In the last years functional neuroimaging has become largely widespread thanks to the use of molecular tracers employed in cellular metabolism which has significantly improved the management of patients with brain tumors, especially in the post-treatment phase. Despite the considerable progress of molecular imaging in oncology its use in the diagnosis of brain tumors is still limited by a few wellknown technical problems. Because 18F-FDG, the most common radiotracer used in oncology, is avidly accumulated by normal cortex, the low tumor/background signal ratio makes it difficult to distinguish the tumor from normal surrounding tissues. By contrast, radiotracers with higher specificity for the tumor are labeled with a short half-life isotopes which restricts their use to those centers equipped with a cyclotron and radiopharmacy facility. 11C-choline has been reported as a suitable tracer for neuroimaging application. The recent availability of choline labeled with a long half-life radioisotope as 18F increases the possibility of studying this tracer's potential role in the staging of brain tumors. The present review focuses on the possible clinical applications of PET/CT with choline tracers in malignant brain tumors and brain metastases, with a special focus on malignant gliomas. PMID:25225894

  10. Heterologous expression and purification of biologically active domains 3 and 4 of human polymeric immunoglobulin receptor and its interaction with choline binding protein A of Streptococcus pneumoniae.

    PubMed

    Venables, Luanne; Govender, Sharlene; Oosthuizen, Vaughan

    2013-10-01

    Streptococcus pneumoniae, one of the common causes of pneumonia, colonises the epithelium via the interaction between a choline binding protein of S. pneumoniae and the human polymeric immunoglobulin receptor (pIgR). One of the functions of pIgR is to mediate the transcytosis of polymeric immunoglobulins from the basolateral to the apical surface of epithelial cells. S. pneumoniae invades human epithelial cells by exploiting the transcytosis machinery. Due to an increase in the prevalence of antibiotic resistant strains of S. pneumoniae, and the limitations and expense of the vaccines available, extensive research may provide insights into the potential of new therapeutic regimes. This study investigated the potential of pIgR domains as an alternative non-antibiotic immune therapy for treating pneumonia. The aim was to determine the binding affinity of recombinant D3D4 protein, the domains of pIgR responsible for binding S. pneumoniae, to recombinant R1R2 repeat domains of choline binding protein A of S. pneumoniae. Biologically active recombinant D3D4 was produced in Escherichia coli using a gel filtration chromatography refolding method, a novel approach for the refolding of pIgR domains, after the purification of inclusion bodies using nickel affinity chromatography. Surface Plasmon resonance (SPR) spectroscopy showed that purified recombinant D3D4 binds recombinant R1R2 with an equilibrium dissociation constant (KD) of 3.36×10(-7)M. PMID:23973337

  11. Choline deficiency increases lymphocyte apoptosis and DNA damage in humans2,3

    PubMed Central

    da Costa, Kerry-Ann; Niculescu, Mihai D; Craciunescu, Corneliu N; Fischer, Leslie M; Zeisel, Steven H

    2008-01-01

    Background: Whereas deficiency of the essential nutrient choline is associated with DNA damage and apoptosis in cell and rodent models, it has not been shown in humans. Objective: The objective was to ascertain whether lymphocytes from choline-deficient humans had greater DNA damage and apoptosis than did those from choline-sufficient humans. Design: Fifty-one men and women aged 18–70 y were fed a diet containing the recommended adequate intake of choline (control) for 10 d. They then were fed a choline-deficient diet for up to 42 d before repletion with 138–550 mg choline/d. Blood was collected at the end of each phase, and peripheral lymphocytes were isolated. DNA damage and apoptosis were then assessed by activation of caspase-3, terminal deoxynucleotide transferase–mediated dUTP nick end-labeling, and single-cell gel electrophoresis (COMET) assays. Results: All subjects fed the choline-deficient diet had lymphocyte DNA damage, as assessed by COMET assay, twice that found when they were fed the control diet. The subjects who developed organ dysfunction (liver or muscle) when fed the choline-deficient diet had significantly more apoptotic lymphocytes, as assessed by the activated caspase-3 assay, than when fed the control diet. Conclusions: A choline-deficient diet increased DNA damage in humans. Subjects in whom these diets induced liver or muscle dys-function also had higher rates of apoptosis in their peripheral lymphocytes than did subjects who did not develop organ dysfunction. Assessment of DNA damage and apoptosis in lymphocytes appears to be a clinically useful measure in humans (such as those receiving parenteral nutrition) in whom choline deficiency is suspected. PMID:16825685

  12. CHOLINE AMELIORATES DEFICITS IN BALANCE CAUSED BY ACUTE NEONATAL ETHANOL EXPOSURE

    PubMed Central

    Bearer, Cynthia F.; Wellmann, Kristen A.; Tang, Ningfeng; He, Min; Mooney, Sandra M.

    2015-01-01

    Fetal alcohol spectrum disorder (FASD) is estimated to occur in 1% of all live births. The developing cerebellum is vulnerable to the toxic effects of alcohol. People with FASD have cerebellar hypoplasia and developmental deficits associated with cerebellar injury. Choline is an essential nutrient but many diets in the USA are choline deficient. In rats, choline given with or following alcohol exposure reduces many alcohol-induced neurobehavioral deficits, but not those associated with cerebellar function. Our objective was to determine if choline supplementation prior to alcohol exposure would ameliorate the impact of ethanol on a cerebellar-associated behavioral test in mice. Pregnant C57Bl6/J mice were maintained on a choline deficient diet from embryonic day 4.5. On postnatal day 1 (P1), pups were assigned to one of 8 treatment groups: choline (C) or saline (S) pre-treatment from P1-5, ethanol (6 g/kg) or Intralipid® on P5, C or S post-treatment from P6-20. On P30, balance and coordination were tested using the dowel crossing test. Overall, there was a significant effect of treatment and females crossed longer distances than males. Ethanol exposure significantly reduced the total distance crossed. Choline pre-treatment increased the distance crossed by males, and both pre- and post-treatment with choline significantly increased total distance crossed for females and males. There was no effect of choline on Intralipid®-exposed animals. This is the first study to show that choline ameliorates ethanol-induced effects on balance and coordination when given before ethanol exposure. Choline fortification of common foodstuffs may reduce the effects of alcohol. PMID:26085462

  13. Dietary Choline and Betaine Intakes Vary in an Adult Multiethnic Population123

    PubMed Central

    Yonemori, Kim M.; Lim, Unhee; Koga, Karin R.; Wilkens, Lynne R.; Au, Donna; Boushey, Carol J.; Le Marchand, Loïc; Kolonel, Laurence N.; Murphy, Suzanne P.

    2013-01-01

    Choline and betaine are important nutrients for human health, but reference food composition databases for these nutrients became available only recently. We tested the feasibility of using these databases to estimate dietary choline and betaine intakes among ethnically diverse adults who participated in the Multiethnic Cohort (MEC) Study. Of the food items (n = 965) used to quantify intakes for the MEC FFQ, 189 items were exactly matched with items in the USDA Database for the Choline Content of Common Foods for total choline, choline-containing compounds, and betaine, and 547 items were matched to the USDA National Nutrient Database for Standard Reference for total choline (n = 547) and 148 for betaine. When a match was not found, choline and betaine values were imputed based on the same food with a different form (124 food items for choline, 300 for choline compounds, 236 for betaine), a similar food (n = 98, 284, and 227, respectively) or the closest item in the same food category (n = 6, 191, and 157, respectively), or the values were assumed to be zero (n = 1, 1, and 8, respectively). The resulting mean intake estimates for choline and betaine among 188,147 MEC participants (aged 45–75) varied by sex (372 and 154 mg/d in men, 304 and 128 mg/d in women, respectively; P-heterogeneity < 0.0001) and by race/ethnicity among Caucasians, African Americans, Japanese Americans, Latinos, and Native Hawaiians (P-heterogeneity < 0.0001), largely due to the variation in energy intake. Our findings demonstrate the feasibility of assessing choline and betaine intake and characterize the variation in intake that exists in a multiethnic population. PMID:23616508

  14. Restoration of blood pressure by choline treatment in rats made hypotensive by haemorrhage.

    PubMed Central

    Ulus, I. H.; Arslan, B. Y.; Savci, V.; Kiran, B. K.

    1995-01-01

    1. Intracerebroventricular (i.c.v.) injection of choline (25-150 micrograms) increased blood pressure in rats made acutely hypotensive by haemorrhage. Intraperitoneal administration of choline (60 mg kg-1) also increased blood pressure, but to a lesser extent. Following i.c.v. injection of 25 micrograms or 50 micrograms of choline, heart rate did not change, while 100 micrograms or 150 micrograms i.c.v. choline produced a slight and short lasting bradycardia. Choline (150 micrograms) failed to alter the circulating residual volume of blood in haemorrhaged rats. 2. The pressor response to i.c.v. choline (50 micrograms) in haemorrhaged rats was abolished by pretreatment with mecamylamine (50 micrograms, i.c.v.) but not atropine (10 micrograms, i.c.v.). The pressor response to choline was blocked by pretreatment with hemicholinium-3 (20 micrograms, i.c.v.). 3. The pressor response to i.c.v. choline (150 micrograms) was associated with a several fold increase in plasma levels of vasopressin and adrenaline but not of noradrenaline and plasma renin. 4. The pressor response to i.c.v. choline (150 micrograms) was not altered by bilateral adrenalectomy, but was attenuated by systemic administration of either phentolamine (10 mg kg-1) or the vasopressin antagonist [beta-mercapto-beta,beta-cyclopenta-methylenepropionyl1, O-Me-Tyr2,Arg8]-vasopressin (10 micrograms kg-1). 5. It is concluded that the precursor of acetylcholine, choline, can increase and restore blood pressure in acutely haemorrhaged rats by increasing central cholinergic neurotransmission. Nicotinic receptor activation and an increase in plasma vasopressin and adrenaline level appear to be involved in this effect of choline. PMID:8528579

  15. Folate intake, MTHFR genotype, and sex modulate choline metabolism in mice.

    PubMed

    Chew, Tina W; Jiang, Xinyin; Yan, Jian; Wang, Wei; Lusa, Amanda L; Carrier, Bradley J; West, Allyson A; Malysheva, Olga V; Brenna, J Thomas; Gregory, Jesse F; Caudill, Marie A

    2011-08-01

    Choline and folate are interrelated in 1-carbon metabolism, mostly because of their shared function as methyl donors for homocysteine remethylation. Folate deficiency and mutations of methylenetetrahydrofolate reductase (MTHFR) reduce the availability of a major methyl donor, 5-methyltetrahydrofolate, which in turn may lead to compensatory changes in choline metabolism. This study investigated the hypothesis that reductions in methyl group supply, either due to dietary folate deficiency or Mthfr gene deletion, would modify tissue choline metabolism in a sex-specific manner. Mthfr wild type (+/+) or heterozygous (+/-) knockout mice were randomized to a folate-deficient or control diet for 8 wk during which time deuterium-labeled choline (d9-choline) was consumed in the drinking water (~10 μmol/d). Mthfr heterozygosity did not alter brain choline metabolite concentrations, but it did enhance their labeling in males (P < 0.05) and tended to do so in females (P < 0.10), a finding consistent with greater turnover of dietary choline in brains of +/- mice. Dietary folate deficiency in females yielded 52% higher (P = 0.027) hepatic glycerophosphocholine, which suggests that phosphatidylcholine (PtdCho) degradation was enhanced. Labeling of the hepatic PtdCho in d3 form was also reduced (P < 0.001) in females, which implies that fewer of the dietary choline-derived methyl groups were used for de novo PtdCho biosynthesis under conditions of folate insufficiency. Males responded to folate restriction with a doubling (P < 0.001) of hepatic choline dehydrogenase transcripts, a finding consistent with enhanced conversion of choline to the methyl donor, betaine. Collectively, these data show that several adaptations in choline metabolism transpire as a result of mild perturbations in folate metabolism, presumably to preserve methyl group homeostasis. PMID:21697299

  16. Measuring the serotonin uptake site using (/sup 3/H)paroxetine--a new serotonin uptake inhibitor

    SciTech Connect

    Gleiter, C.H.; Nutt, D.J.

    1988-01-01

    Serotonin is an important neurotransmitter that may be involved in ethanol preference and dependence. It is possible to label the serotonin uptake site in brain using the tricyclic antidepressant imipramine, but this also binds to other sites. We have used the new high-affinity uptake blocker paroxetine to define binding to this site and report it to have advantages over imipramine as a ligand.

  17. Local Affinity Release.

    PubMed

    Delplace, Vianney; Obermeyer, Jaclyn; Shoichet, Molly S

    2016-07-26

    The use of hydrogels for therapeutic delivery is a burgeoning area of investigation. These water-swollen polymer matrices are ideal platforms for localized drug delivery that can be further combined with specific ligands or nanotechnologies to advance the controlled release of small-molecule drugs and proteins. Due to the advantage of hydrophobic, electrostatic, or specific extracellular matrix interactions, affinity-based strategies can overcome burst release and challenges associated with encapsulation. Future studies will provide innovative binding tools, truly stimuli-responsive systems, and original combinations of emerging technologies to control the release of therapeutics spatially and temporally. Local drug delivery can be achieved by directly injecting a therapeutic to its site of action and is advantageous because off-target effects associated with systemic delivery can be minimized. For prolonged benefit, a vehicle that provides sustained drug release is required. Hydrogels are versatile platforms for localized drug release, owing to the large library of biocompatible building blocks from which they can be formed. Injectable hydrogel formulations that gel quickly in situ and provide sustained release of therapeutics are particularly advantageous to minimize invasiveness. The incorporation of polymers, ligands or nanoparticles that have an affinity for the therapeutic of interest improve control over the release of small-molecule drugs and proteins from hydrogels, enabling spatial and temporal control over the delivery. Such affinity-based strategies can overcome drug burst release and challenges associated with protein instability, allowing more effective therapeutic molecule delivery for a range of applications from therapeutic contact lenses to ischemic tissue regeneration. PMID:27403513

  18. PLASMA CHOLINE IN NORMAL NEWBORNS, INFANTS, TODDLERS, AND IN VERY-LOW-BIRTH-WEIGHT NEONATES REQUIRING TOTAL PARENTERAL NUTRITION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Choline deficiency is associated with hepatic abnormalities in adult volunteers and patients administered total parenteral nutrition (TPN). Preliminary investigation has suggested that plasma-free choline concentration (PFCh) is greater in neonatal animals, including humans, than in adults. The aims...

  19. Determination of Cooking Yields and Nutrient Retention Factors of Choline in Meat Products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    USDA’s recent research shows that meat products are good sources of choline. During cooking, nutrient levels are affected by moisture and fat losses and may be reduced by heating. To determine the impact of cooking on choline retention in meats, four nationwide composite samples of beef, bacon, cure...

  20. Theoretical study on the structures and properties of mixtures of urea and choline chloride.

    PubMed

    Sun, Hui; Li, Yan; Wu, Xue; Li, Guohui

    2013-06-01

    In this work, we investigated in detail the structural characteristics of mixtures of choline chloride and urea with different urea contents by performing molecular dynamic (MD) simulations, and offer possible explanations for the low melting point of the eutectic mixture of choline chloride and urea with a ratio of 1:2. The insertion of urea molecules was found to change the density distribution of cations and anions around the given cations significantly, disrupting the long-range ordered structure of choline chloride. Moreover, with increasing urea concentration, the hydrogen bond interactions between choline cations and Cl(-) anions decreased, while those among urea molecules obviously increased. From the hydrogen bond lifetimes, it was found that a ratio of 1:2 between choline chloride and urea is necessary for a reasonable strength of hydrogen bond interaction to maintain the low melting point of the mixture of choline chloride with urea. In addition, it was also deduced from the interaction energies that a urea content of 67.7 % may make the interactions of cation-anion, cation-urea and anion-urea modest, and thus results in the lower melting point of the eutectic mixture of choline chloride and urea. The present results may offer assistance to some extent for understanding the physicochemical properties of the eutectic mixture of choline chloride and urea, and give valuable information for the further development and application of deep eutectic solvents. PMID:23435478

  1. USDA Database for the Choline Content of Common Foods, Release Two

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research has shown that choline is important for the synthesis of phospholipids in cell membranes, methyl metabolism, acetylcholine synthesis, and cholinergic neurotransmission in humans. Betaine, a choline derivative, is also important because of its role in the donation of methyl groups to homocy...

  2. Fewer metabolites of dietary choline reach the blood of rats after treatment with lithium

    SciTech Connect

    Pomfret, E.A.; O'Connor, S.C.; Zola, T.H.; Zeisel, S.H.

    1988-01-01

    The authors studies the effect of lithium treatment upon the appearance in blood, liver and intestine of metabolites formed from dietary choline. Rats were treated for 9 days with 2 mEq/kg lithium carbonate or water. Animals were fasted overnight, and on the 10th day were fed with a solution containing radiolabeled choline chloride. The lithium treated groups also received 2.0 mEq/kg lithium as part of this solution. After an oral dose of 1 ml of a 1 mM choline solution, the lithium-treated animals had significantly lower levels of choline derived radiolabel in blood than did controls at 30, 60, 120, and 180 minutes (47%, 51%, 59% and 74%, respectively). They observed similar decreases of the accumulation in blood, at 180 minutes after the dose, of choline-derived radiolabel when choline was administered at lower or higher concentrations. After an oral treatment containing 0.1, 1 or 10 mM choline, lithium treated animals accumulated 69%, 66% and 72% as much radiolabel in serum as did controls. Most of the radiolabel found in blood at 180 minutes was in metabolites of choline which are formed within liver. The diminished accumulation of radiolabel in serum after lithium treatment was not due to increased accumulation of label by erythrocytes, liver or gut wall. They suggest that lithium influences the release by liver of betaine and phosphatidylcholine. 36 references, 5 figures.

  3. Prenatal Choline Availability Alters the Context Sensitivity of Pavlovian Conditioning in Adult Rats

    ERIC Educational Resources Information Center

    Lamoureux, Jeffrey A.; Meck, Warren H.; Williams, Christina L.

    2008-01-01

    The effects of prenatal choline availability on Pavlovian conditioning were assessed in adult male rats (3-4 mo). Neither supplementation nor deprivation of prenatal choline affected the acquisition and extinction of simple Pavlovian conditioned excitation, or the acquisition and retardation of conditioned inhibition. However, prenatal choline…

  4. Are dietary choline and betaine intakes determinants of total homocysteine concentration?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Elevated homocysteine concentrations are associated with an increased risk of cardiovascular disease and a decline in cognitive function. Intakes of choline and betaine, as methyl donors, may affect homocysteine concentrations. The objective was to examine whether choline and betaine intakes, assess...

  5. Calixarene-Mediated Liquid Membrane Transport of Choline Conjugates 2: Transport of Drug-Choline Conjugates and Neurotransmitters

    PubMed Central

    Adhikari, Birendra Babu; Roshandel, Sahar; Fujii, Ayu

    2015-01-01

    Lower rim carboxylic acid calix[n]arenes and upper rim phosphonic acid functionalized calix[4]arenes effect selective transport of distinct molecular payloads through a liquid membrane. The secret to this success lies in the attachment of a receptor-complementary handle. We find that the trimethylammonium ethylene group present in choline is a general handle for the transport of drug and drug-like species. Furthermore, neurotransmitters possessing ionizable amine termini are also transported. Some limitations to this strategy have been uncovered as payloads become increasingly lipophilic. These developments reveal new approaches to synthetic receptor-mediated selective small molecule transport in vesicular and cellular systems. PMID:26161035

  6. Moderate Perinatal Choline Deficiency Elicits Altered Physiology and Metabolomic Profiles in the Piglet.

    PubMed

    Getty, Caitlyn M; Dilger, Ryan N

    2015-01-01

    Few studies have evaluated the impact of dietary choline on the health and well-being of swine, and those pivotal papers were aimed at determining dietary requirements for sows and growing pigs. This is of importance as the piglet is becoming a widely accepted model for human infant nutrition, but little is known about the impacts of perinatal choline status on overall health and metabolism of the growing piglet. In the present study, sows were provided either a choline deficient (CD, 625 mg choline/kg dry matter) or choline sufficient (CS, 1306 mg choline/kg dry matter) diet for the last 65 d of gestation (prenatal intervention). Piglets were weaned from the sow 48 h after farrowing and provided either a CD (477 mg choline/kg dry matter) or CS (1528 mg choline/kg dry matter) milk replacer (postnatal intervention) for 29 ± 2 d, resulting in a factorial arrangement of 4 treatment (prenatal/postnatal) groups: CS/CS, CS/CD, CD/CS, and CD/CD. Piglet growth was normal for artificially-reared piglets, and was not impacted by perinatal choline status. Piglets receiving the postnatal CD treatment had lower (P < 0.01) plasma choline and choline-containing phospholipid concentrations and higher (P < 0.05) liver enzyme (alkaline phosphatase and gamma-glutamyl transferase) values compared with piglets receiving the postnatal CS treatment. Hepatic lipid content of piglets receiving the postnatal CD treatment was higher (P < 0.01) compared with piglets receiving the postnatal CS treatment. Additionally, postnatally CD piglets had lower (P = 0.01) plasma cholesterol than postnatally CS piglets. Brain development was also impacted by perinatal choline status, with brains of piglets exposed to prenatal CD being smaller (P = 0.01) than those of prenatally CS piglets. These findings support the hypothesis that the piglet is a sensitive model for choline deficiency during the perinatal period. In the present study, piglets exhibited similarities in health markers and metabolomic

  7. Moderate Perinatal Choline Deficiency Elicits Altered Physiology and Metabolomic Profiles in the Piglet

    PubMed Central

    Getty, Caitlyn M.; Dilger, Ryan N.

    2015-01-01

    Few studies have evaluated the impact of dietary choline on the health and well-being of swine, and those pivotal papers were aimed at determining dietary requirements for sows and growing pigs. This is of importance as the piglet is becoming a widely accepted model for human infant nutrition, but little is known about the impacts of perinatal choline status on overall health and metabolism of the growing piglet. In the present study, sows were provided either a choline deficient (CD, 625 mg choline/kg dry matter) or choline sufficient (CS, 1306 mg choline/kg dry matter) diet for the last 65 d of gestation (prenatal intervention). Piglets were weaned from the sow 48 h after farrowing and provided either a CD (477 mg choline/kg dry matter) or CS (1528 mg choline/kg dry matter) milk replacer (postnatal intervention) for 29 ± 2 d, resulting in a factorial arrangement of 4 treatment (prenatal/postnatal) groups: CS/CS, CS/CD, CD/CS, and CD/CD. Piglet growth was normal for artificially-reared piglets, and was not impacted by perinatal choline status. Piglets receiving the postnatal CD treatment had lower (P < 0.01) plasma choline and choline-containing phospholipid concentrations and higher (P < 0.05) liver enzyme (alkaline phosphatase and gamma-glutamyl transferase) values compared with piglets receiving the postnatal CS treatment. Hepatic lipid content of piglets receiving the postnatal CD treatment was higher (P < 0.01) compared with piglets receiving the postnatal CS treatment. Additionally, postnatally CD piglets had lower (P = 0.01) plasma cholesterol than postnatally CS piglets. Brain development was also impacted by perinatal choline status, with brains of piglets exposed to prenatal CD being smaller (P = 0.01) than those of prenatally CS piglets. These findings support the hypothesis that the piglet is a sensitive model for choline deficiency during the perinatal period. In the present study, piglets exhibited similarities in health markers and metabolomic

  8. Choline magnesium trisalicylate in patients with aspirin-induced asthma.

    PubMed

    Szczeklik, A; Nizankowska, E; Dworski, R

    1990-05-01

    Treatment of inflammatory diseases of asthmatics can be a serious problem since some patients show intolerance to aspirin and other non-steroidal, anti-inflammatory drugs that are cyclooxygenase inhibitors. Salicylates were believed to be well tolerated, but recent reports have demonstrated that diflunisal and salicylsalicylic acid can precipitate asthma attacks in aspirin-intolerant patients. This study was designed to determine the tolerance of choline magnesium trisalicylate (CMT), a nonacetylated salicylate with potent analgesic and anti-inflammatory activity, in 23 asthmatics with aspirin hypersensitivity confirmed by oral challenge. The study consisted of three phases: 1) patients received increasing doses (50-1,500 mg) of CMT under a single-blind protocol; 2) patients received either a placebo or CMT challenge in a double-blind, randomized, cross-over design; 3) patients received CMT at daily 3,000 mg doses for 1 week. Throughout the study, pulmonary function tests, peak nasal inspiratory flow, and serum salicylate and thromboxane B2 (TXB2) levels were monitored. Results showed no airway obstruction, nasal congestion or rhinorrhea after CMT. There was no significant decrease in serum TXB2 levels, indicating the absence of cyclooxygenase inhibition with CMT. We conclude that choline magnesium trisalicylate is a safe drug for treatment of different anti-inflammatory disorders in asthmatics with aspirin hypersensitivity. PMID:2198165

  9. Brucella abortus Synthesizes Phosphatidylcholine from Choline Provided by the Host

    PubMed Central

    Comerci, Diego J.; Altabe, Silvia; de Mendoza, Diego; Ugalde, Rodolfo A.

    2006-01-01

    The Brucella cell envelope is characterized by the presence of phosphatidylcholine (PC), a common phospholipid in eukaryotes that is rare in prokaryotes. Studies on the composition of Brucella abortus 2308 phospholipids revealed that the synthesis of PC depends on the presence of choline in the culture medium, suggesting that the methylation biosynthetic pathway is not functional. Phospholipid composition of pmtA and pcs mutants indicated that in Brucella, PC synthesis occurs exclusively via the phosphatidylcholine synthase pathway. Transformation of Escherichia coli with an expression vector containing the B. abortus pcs homologue was sufficient for PC synthesis upon induction with IPTG (isopropyl-β-d-thiogalactopyranoside), while no PC formation was detected when bacteria were transformed with a vector containing pmtA. These findings imply that Brucella depends on choline provided by the host cell to form PC. We could not detect any obvious associated phenotype in the PC-deficient strain under vegetative or intracellular growth conditions in macrophages. However, the pcs mutant strain displays a reproducible virulence defect in mice, which suggests that PC is necessary to sustain a chronic infection process. PMID:16484204

  10. Brucella abortus synthesizes phosphatidylcholine from choline provided by the host.

    PubMed

    Comerci, Diego J; Altabe, Silvia; de Mendoza, Diego; Ugalde, Rodolfo A

    2006-03-01

    The Brucella cell envelope is characterized by the presence of phosphatidylcholine (PC), a common phospholipid in eukaryotes that is rare in prokaryotes. Studies on the composition of Brucella abortus 2308 phospholipids revealed that the synthesis of PC depends on the presence of choline in the culture medium, suggesting that the methylation biosynthetic pathway is not functional. Phospholipid composition of pmtA and pcs mutants indicated that in Brucella, PC synthesis occurs exclusively via the phosphatidylcholine synthase pathway. Transformation of Escherichia coli with an expression vector containing the B. abortus pcs homologue was sufficient for PC synthesis upon induction with IPTG (isopropyl-beta-d-thiogalactopyranoside), while no PC formation was detected when bacteria were transformed with a vector containing pmtA. These findings imply that Brucella depends on choline provided by the host cell to form PC. We could not detect any obvious associated phenotype in the PC-deficient strain under vegetative or intracellular growth conditions in macrophages. However, the pcs mutant strain displays a reproducible virulence defect in mice, which suggests that PC is necessary to sustain a chronic infection process. PMID:16484204

  11. Morphometric affinities of gigantopithecus.

    PubMed

    Gelvin, B R

    1980-11-01

    Multivariate analyses, supplemented by univariate statistical methods, of measurements from mandibular tooth crown dimensions and the mandible of Gigantopithecus blacki, G. bilaspurensis, Plio-Plelstocene hominids, Homo erectus, and seven Neogene ape species from the genera Proconsul, Sivapithecus, Ouranopithecus, and Dryopithecus were used to assess the morphometric affinities of Gigantopithecus. The results show that Gigantopithecus displays affinities to Ouranopithecus and to the hominids, particularly the Plio-Plelstocene hominids, rather than to the apes. Ouranopithecus demonstrated dental resemblances to G. bilaspurensis and the Plio-Pleistocene hominids but mandibular similarities to the apes. Results of analyses of tooth and mandibular shape indices, combined with multivariate distance and temporal relationships, suggest that Ouranopithecus is a more likely candidate for Gigantopithecus ancestry than is Silvapithecus indicus. Shape and allometric differences between G. bilaspurensis and the robust australopithecines weaken the argument for an ancestral-descendant relationship between these groups. The results support the hypothesis that Gigantopithecus is an extinct side branch of the Hominidae. PMID:7468790

  12. The crystal structure of choline kinase reveals a eukaryotic protein kinase fold

    SciTech Connect

    Peisach, D.; Gee, P.; Kent, K.; Xu, Z.

    2010-03-08

    Choline kinase catalyzes the ATP-dependent phosphorylation of choline, the first committed step in the CDP-choline pathway for the biosynthesis of phosphatidylcholine. The 2.0 {angstrom} crystal structure of a choline kinase from C. elegans (CKA-2) reveals that the enzyme is a homodimeric protein with each monomer organized into a two-domain fold. The structure is remarkably similar to those of protein kinases and aminoglycoside phosphotransferases, despite no significant similarity in amino acid sequence. Comparisons to the structures of other kinases suggest that ATP binds to CKA-2 in a pocket formed by highly conserved and catalytically important residues. In addition, a choline binding site is proposed to be near the ATP binding pocket and formed by several structurally flexible loops.

  13. Live-cell vibrational imaging of choline metabolites by stimulated Raman scattering coupled with isotope-based metabolic labeling

    PubMed Central

    Hu, Fanghao; Wei, Lu; Zheng, Chaogu; Shen, Yihui

    2014-01-01

    Choline is a small molecule that occupies a key position in the biochemistry of all living organisms. Recent studies have strongly implicated choline metabolites in cancer, atherosclerosis and nervous system development. To detect choline and its metabolites, existing physical methods such as magnetic resonance spectroscopy and positron emission tomography, are often limited by the poor spatial resolution and substantial radiation dose. Fluorescence imaging, although with submicrometer resolution, requires introduction of bulky fluorophores and thus is difficult in labeling the small choline molecule. By combining the emerging bond-selective stimulated Raman scattering microscopy with metabolic incorporation of deuterated choline, herein we have achieved high resolution imaging of choline-containing metabolites in living mammalian cell lines, primary hippocampal neurons and multicellular organism C. elegans. Different subcellular distributions of choline metabolites are observed between cancer cells and non-cancer cells, which may reveal functional difference in the choline metabolism and lipid-mediated signaling events. In neurons, choline incorporation is visualized within both soma and neurites, where choline metabolites are more evenly distributed compared to the protein. Furthermore, choline localization is also observed in the pharynx region of C. elegans larvae, consistent with its organogenesis mechanism. These applications demonstrate the potential of isotope-based stimulated Raman scattering microscopy for future choline-related disease detection and development monitoring in vivo. PMID:24555181

  14. Evidence for negative selection of gene variants that increase dependence on dietary choline in a Gambian cohort.

    PubMed

    Silver, Matt J; Corbin, Karen D; Hellenthal, Garrett; da Costa, Kerry-Ann; Dominguez-Salas, Paula; Moore, Sophie E; Owen, Jennifer; Prentice, Andrew M; Hennig, Branwen J; Zeisel, Steven H

    2015-08-01

    Choline is an essential nutrient, and the amount needed in the diet is modulated by several factors. Given geographical differences in dietary choline intake and disparate frequencies of single-nucleotide polymorphisms (SNPs) in choline metabolism genes between ethnic groups, we tested the hypothesis that 3 SNPs that increase dependence on dietary choline would be under negative selection pressure in settings where choline intake is low: choline dehydrogenase (CHDH) rs12676, methylenetetrahydrofolate reductase 1 (MTHFD1) rs2236225, and phosphatidylethanolamine-N-methyltransferase (PEMT) rs12325817. Evidence of negative selection was assessed in 2 populations: one in The Gambia, West Africa, where there is historic evidence of a choline-poor diet, and the other in the United States, with a comparatively choline-rich diet. We used 2 independent methods, and confirmation of our hypothesis was sought via a comparison with SNP data from the Maasai, an East African population with a genetic background similar to that of Gambians but with a traditional diet that is higher in choline. Our results show that frequencies of SNPs known to increase dependence on dietary choline are significantly reduced in the low-choline setting of The Gambia. Our findings suggest that adequate intake levels of choline may have to be reevaluated in different ethnic groups and highlight a possible approach for identifying novel functional SNPs under the influence of dietary selective pressure. PMID:25921832

  15. Feeding a diet devoid of choline to lactating rodents restricts growth and lymphocyte development in offspring.

    PubMed

    Lewis, E D; Goruk, S; Richard, C; Dellschaft, N S; Curtis, J M; Jacobs, R L; Field, C J

    2016-09-01

    The nutrient choline is necessary for membrane synthesis and methyl donation, with increased requirements during lactation. The majority of immune development occurs postnatally, but the importance of choline supply for immune development during this critical period is unknown. The objective of this study was to determine the importance of maternal supply of choline during suckling on immune function in their offspring among rodents. At parturition, Sprague-Dawley dams were randomised to either a choline-devoid (ChD; n 7) or choline-sufficient (ChS, 1 g/kg choline; n 10) diet with their offspring euthanised at 3 weeks of age. In a second experiment, offspring were weaned to a ChS diet until 10 weeks of age (ChD-ChS, n 5 and ChS-ChS, n 9). Splenocytes were isolated, and parameters of immune function were measured. The ChD offspring received less choline in breast milk and had lower final body and organ weight compared with ChS offspring (P<0·05), but this effect disappeared by week 10 with choline supplementation from weaning. ChD offspring had a higher proportion of T cells expressing activation markers (CD71 or CD28) and a lower proportion of total B cells (CD45RA+) and responded less to T cell stimulation (lower stimulation index and less IFN-γ production) ex vivo (P<0·05). ChD-ChS offspring had a lower proportion of total and activated CD4+ T cells, and produced less IL-6 after mitogen stimulation compared with cells from ChS-ChS (P<0·05). Our study suggests that choline is required in the suckling diet to facilitate immune development, and choline deprivation during this critical period has lasting effects on T cell function later in life. PMID:27480608

  16. Non-invasive in vivo imaging of early metabolic tumor response to therapies targeting choline metabolism.

    PubMed

    Mignion, Lionel; Danhier, Pierre; Magat, Julie; Porporato, Paolo E; Masquelier, Julien; Gregoire, Vincent; Muccioli, Giulio G; Sonveaux, Pierre; Gallez, Bernard; Jordan, Bénédicte F

    2016-04-15

    The cholinic phenotype, characterized by elevated phosphocholine and a high production of total-choline (tCho)-containing metabolites, is a metabolic hallmark of cancer. It can be exploited for targeted therapy. Non-invasive imaging biomarkers are required to evaluate an individual's response to targeted anticancer agents that usually do not rapidly cause tumor shrinkage. Because metabolic changes can manifest at earlier stages of therapy than changes in tumor size, the aim of the current study was to evaluate (1)H-MRS and diffusion-weighted MRI (DW-MRI) as markers of tumor response to the modulation of the choline pathway in mammary tumor xenografts. Inhibition of choline kinase activity was achieved with the direct pharmacological inhibitor H-89, indirect inhibitor sorafenib and down-regulation of choline-kinase α (ChKA) expression using specific short-hairpin RNA (shRNA). While all three strategies significantly decreased tCho tumor content in vivo, only sorafenib and anti-ChKA shRNA significantly repressed tumor growth. The increase of apparent-diffusion-coefficient of water (ADCw) measured by DW-MRI, was predictive of the induced necrosis and inhibition of the tumor growth in sorafenib treated mice, while the absence of change in ADC values in H89 treated mice predicted the absence of effect in terms of tumor necrosis and tumor growth. In conclusion, (1)H-choline spectroscopy can be useful as a pharmacodynamic biomarker for choline targeted agents, while DW-MRI can be used as an early marker of effective tumor response to choline targeted therapies. DW-MRI combined to choline spectroscopy may provide a useful non-invasive marker for the early clinical assessment of tumor response to therapies targeting choline signaling. PMID:26595604

  17. AtKUP1: an Arabidopsis gene encoding high-affinity potassium transport activity.

    PubMed Central

    Kim, E J; Kwak, J M; Uozumi, N; Schroeder, J I

    1998-01-01

    Because plants grow under many different types of soil and environmental conditions, we investigated the hypothesis that multiple pathways for K+ uptake exist in plants. We have identified a new family of potassium transporters from Arabidopsis by searching for homologous sequences among the expressed sequence tags of the GenBank database. The deduced amino acid sequences of AtKUP (for Arabidopsis thaliana K+ uptake transporter) cDNAs are highly homologous to the non-plant Kup and HAK1 potassium transporters from Escherichia coli and Schwanniomyces occidentalis, respectively. Interestingly, AtKUP1 and AtKUP2 are able to complement the potassium transport deficiency of an E. coli triple mutant. In addition, transgenic Arabidopsis suspension cells overexpressing AtKUP1 showed increased Rb+ uptake at micromolar concentrations with an apparent K(m) of approximately 22 microM, indicating that AtKUP1 encodes a high-affinity potassium uptake activity in vivo. A small, low-affinity Rb+ uptake component was also detected in AtKUP1-expressing cells. RNA gel blot analysis showed that the various members of the AtKUP family have distinct patterns of expression, with AtKUP3 transcript levels being strongly induced by K+ starvation. It is proposed that plants contain multiple potassium transporters for high-affinity uptake and that the AtKUP family may provide important components of high- and low-affinity K+ nutrition and uptake into various plant cell types. PMID:9477571

  18. Adjoint affine fusion and tadpoles

    NASA Astrophysics Data System (ADS)

    Urichuk, Andrew; Walton, Mark A.

    2016-06-01

    We study affine fusion with the adjoint representation. For simple Lie algebras, elementary and universal formulas determine the decomposition of a tensor product of an integrable highest-weight representation with the adjoint representation. Using the (refined) affine depth rule, we prove that equally striking results apply to adjoint affine fusion. For diagonal fusion, a coefficient equals the number of nonzero Dynkin labels of the relevant affine highest weight, minus 1. A nice lattice-polytope interpretation follows and allows the straightforward calculation of the genus-1 1-point adjoint Verlinde dimension, the adjoint affine fusion tadpole. Explicit formulas, (piecewise) polynomial in the level, are written for the adjoint tadpoles of all classical Lie algebras. We show that off-diagonal adjoint affine fusion is obtained from the corresponding tensor product by simply dropping non-dominant representations.

  19. UPTAKE OF RADIONUCLIDE METALS BY SPME FIBERS

    SciTech Connect

    Duff, M; S Crump, S; Robert02 Ray, R; Keisha Martin, K; Donna Beals, D

    2006-08-28

    The Federal Bureau of Investigation (FBI) Laboratory currently does not have on site facilities for handling radioactive evidentiary materials and there are no established FBI methods or procedures for decontaminating high explosive (HE) and fire debris (FD) evidence while maintaining evidentiary value. One experimental method for the isolation of HE and FD residue involves using solid phase microextraction or SPME fibers to remove residue of interest. Due to their high affinity for organics, SPME fibers should have little affinity for most metals. However, no studies have measured the affinity of radionuclides for SPME fibers. The focus of this research was to examine the affinity of dissolved radionuclide ({sup 239/240}Pu, {sup 238}U, {sup 237}Np, {sup 85}Sr, {sup 133}Ba, {sup 137}Cs, {sup 60}Co and {sup 226}Ra) and stable radionuclide surrogate metals (Sr, Co, Ir, Re, Ni, Ba, Cs, Nb, Zr, Ru, and Nd) for SPME fibers at the exposure conditions that favor the uptake of HE and FD residues. Our results from radiochemical and mass spectrometric analyses indicate these metals have little measurable affinity for these SPME fibers during conditions that are conducive to HE and FD residue uptake with subsequent analysis by liquid or gas phase chromatography with mass spectrometric detection.

  20. Motor Neuron-Specific Overexpression of the Presynaptic Choline Transporter: Impact on Motor Endurance and Evoked Muscle Activity

    PubMed Central

    Lund, David; Ruggiero, Alicia M.; Ferguson, Shawn M.; Wright, Jane; English, Brett A.; Reisz, Peter A.; Whitaker, Sarah M.; Peltier, Amanda C.; Blakely, Randy D.

    2010-01-01

    The presynaptic, hemicholinium-3 sensitive, high-affinity choline transporter (CHT) supplies choline for acetylcholine (ACh) synthesis. In mice, a homozygous deletion of CHT (CHT−/−) leads to premature cessation of spontaneous or evoked neuromuscular signaling and is associated with perinatal cyanosis and lethality within 1 hr. Heterozygous (CHT+/−) mice exhibit diminished brain ACh levels and demonstrate an inability to sustain vigorous motor activity. We sought to explore the contribution of CHT gene dosage to motor function in greater detail using transgenic mice where CHT is expressed under control of the motor neuron promoter Hb9 (Hb9:CHT). On a CHT−/− background, the Hb9:CHT transgene conferred mice with the ability to move and breath for a postnatal period of ~24 hrs, thus increasing survival. Conversely, Hb9:CHT expression on a wild-type background (CHT+/+;Hb9:CHT) leads to an increased capacity for treadmill running compared to wild-type littermates. Analysis of the stimulated compound muscle action potential (CMAP) in these animals under basal conditions established that CHT+/+;Hb9:CHT mice display an unexpected, bidirectional change, producing either elevated or reduced CMAP amplitude, relative to CHT+/+ animals. To examine whether these two groups arise from underlying changes in synaptic properties, we used high-frequency stimulation of motor axons to assess CMAP recovery kinetics. Although CHT+/+;Hb9:CHT mice in the two groups display an equivalent, time-dependent reduction in CMAP amplitude, animals with a higher basal CMAP amplitude demonstrate a significantly enhanced rate of recovery. To explain our findings, we propose a model whereby CHT support for neuromuscular signaling involves contributions to ACh synthesis as well as cholinergic synaptic vesicle availability. PMID:20888396

  1. Hyperhomocysteinemia induced by guanidinoacetic acid is effectively suppressed by choline and betaine in rats.

    PubMed

    Setoue, Minoru; Ohuchi, Seiya; Morita, Tatsuya; Sugiyama, Kimio

    2008-07-01

    Rats were fed 25% casein (25C) diets differing in choline levels (0-0.5%) with and without 0.5% guanidinoacetic acid (GAA) or 0.75% L-methionine for 7 d to determine the effects of dietary choline level on experimental hyperhomocysteinemia. The effects of dietary choline (0.30%) and betaine (0.34%) on GAA- and methionine-induced hyperhomocysteinemia were also compared. Dietary choline suppressed hyperhomocysteinemia induced by GAA, but not by methionine, in a dose-dependent manner. GAA-induced enhancement of the plasma homocysteine concentration was suppressed by choline and betaine to the same degree, but the effects of these compounds were relatively small on methionine-induced hyperhomocysteinemia. Dietary supplementation with choline and betaine significantly increased the hepatic betaine concentration in rats fed a GAA diet, but not in rats fed a methionine diet. These results indicate that choline and betaine are effective at relatively low levels in reducing plasma homocysteine, especially under the condition of betaine deficiency without a loading of homocysteine precursor. PMID:18603787

  2. Maternal dietary intake of choline in mice regulates development of the cerebral cortex in the offspring.

    PubMed

    Wang, Yanyan; Surzenko, Natalia; Friday, Walter B; Zeisel, Steven H

    2016-04-01

    Maternal diets low in choline, an essential nutrient, increase the risk of neural tube defects and lead to low performance on cognitive tests in children. However, the consequences of maternal dietary choline deficiency for the development and structural organization of the cerebral cortex remain unknown. In this study, we fed mouse dams either control (CT) or low-choline (LC) diets and investigated the effects of choline on cortical development in the offspring. As a result of a low choline supply between embryonic day (E)11 and E17 of gestation, the number of 2 types of cortical neural progenitor cells (NPCs)-radial glial cells and intermediate progenitor cells-was reduced in fetal brains (P< 0.01). Furthermore, the number of upper layer cortical neurons was decreased in the offspring of dams fed an LC diet at both E17 (P< 0.001) and 4 mo of age (P< 0.001). These effects of LC maternal diet were mediated by a decrease in epidermal growth factor receptor (EGFR) signaling in NPCs related to the disruption of EGFR posttranscriptional regulation. Our findings describe a novel mechanism whereby low maternal dietary intake of choline alters brain development.-Wang, Y., Surzenko, N., Friday, W. B., Zeisel, S. H. Maternal dietary intake of choline in mice regulates development of the cerebral cortex in the offspring. PMID:26700730

  3. Prenatal choline supplementation advances hippocampal development and enhances MAPK and CREB activation.

    PubMed

    Mellott, Tiffany J; Williams, Christina L; Meck, Warren H; Blusztajn, Jan Krzysztof

    2004-03-01

    Choline is an essential nutrient for animals and humans. Previous studies showed that supplementing the maternal diet with choline during the second half of gestation in rats permanently enhances memory performance of the adult offspring. Here we show that prenatal choline supplementation causes a 3-day advancement in the ability of juvenile rats to use relational cues in a water maze task, indicating that the treatment accelerates hippocampal maturation. Moreover, phosphorylation and therefore activation of hippocampal mitogen-activated protein kinase (MAPK) and cAMP-response element binding protein (CREB) in response to stimulation by glutamate, N-methyl-D-aspartate, or depolarizing concentrations of K+ were increased by prenatal choline supplementation and reduced by prenatal choline deficiency. These data provide the first evidence that developmental plasticity of the hippocampal MAPK and CREB signaling pathways is controlled by the supply of a single essential nutrient, choline, during fetal development and point to these pathways as candidate mechanisms for the developmental and long-term cognitive enhancement induced by prenatal choline supplementation. PMID:14715695

  4. Synthesis of acetylcholine from choline derived from phosphatidylcholine in a human neuronal cell line

    SciTech Connect

    Blusztajn, J.K.; Liscovitch, M.; Richardson, U.I.

    1987-08-01

    Cholinergic neurons are unique among cells since they alone utilize choline not only as a component of major membrane phospholipids, such as phosphatidylcholine (Ptd-Cho), but also as a precursor of their neurotransmitter acetylcholine (AcCho). It has been hypothesized that choline-phospholipids might serve as a storage pool of choline for AcCho synthesis. The selective vulnerability of cholinergic neurons in certain neurodegenerative diseases (e.g., Alzheimer disease, motor neuron disorders) might result from the abnormally accelerated liberation of choline (to be used a precursor of AcCho) from membrane phospholipids, resulting in altered membrane composition and function and compromised neuronal viability. However, the proposed metabolic link between membrane turnover and AcCho synthesis has been difficult to demonstrate because of the heterogeneity of the preparations used. Here the authors used a population of purely cholinergic cells (human neuroblastomas, LA-N-2), incubated in the presence of (methyl-/sup 3/H)methionine to selectively label PtdCho synthesized by methylation of phosphatidylethanolamine, the only pathway of de novo choline synthesis. Three peaks of radioactive material that cochromatographed with authentic AcCho, choline, and phosphocholine were observed when the water-soluble metabolites of the (/sup 3/H)PtdCho were purified by high-performance liquid chromatography. The results demonstrate that AcCho can be synthesized from choline derived from the degradation of endogenous PtdCho formed de novo by methylation of phosphatidylethanolamine.

  5. Comparison of the computational NMR chemical shifts of choline with the experimental data

    NASA Astrophysics Data System (ADS)

    Alcorn, C.; Cuperlovic-Culf, M.; Ghandi, K.

    2012-02-01

    One of the main biological markers of the presence of cancer in living patients is an over-expression of total choline (tCho), which is the sum of free choline and its derivatives. 1H Magnetic Resonance Spectroscopy, or H-MRS, enables the quantification of tCho via its proton spectra, and thus has the potential to be a diagnostic tool for the presence of cancer and an accurate early indicator of the response of cancer to treatment. However, it remains difficult to quantify individual choline derivatives, since they share a large structural similarity ((CH3)3-N+-CH2-CH2-O-), of which the strongest signal detectable by MRS is that of the choline "head group": the three methyl groups bonded to the nitrogen. This work used ACENet, a high performance computing system, to attempt to model the NMR parameters of choline derivatives, with the focus of this report being free choline. Optimized structures were determined using Density Functional Theory and the B3LYP electron correlation functional. The Polarizable Continuum Model was used to evaluate solvent effects. The Gauge-Invariant Atomic Orbital method was found to be the superior method for calculating the NMR parameters of cholines.

  6. Choline oxidase, a catabolic enzyme in Arthrobacter pascens, facilitates adaptation to osmotic stress in Escherichia coli.

    PubMed Central

    Rozwadowski, K L; Khachatourians, G G; Selvaraj, G

    1991-01-01

    Choline oxidase (EC 1.1.3.17) is a bifunctional enzyme that is capable of catalyzing glycine betaine biosynthesis from choline via betaine aldehyde. A gene (cox) encoding this enzyme in the gram-positive soil bacterium Arthrobacter pascens was isolated and characterized. This gene is contained within a 1.9-kb fragment that encodes a polypeptide of approximately 66 kDa. Transfer of this gene to an Escherichia coli mutant that is defective in betaine biosynthesis resulted in an osmotolerant phenotype. This phenotype was associated with the ability of the host to synthesize and assemble an enzymatically active choline oxidase that could catalyze biosynthesis of glycine betaine from an exogenous supply of choline. Although glycine betaine functions as an osmolyte in several different organisms, it was not found to have this role in A. pascens. Instead, both choline and glycine betaine were utilized as carbon sources. In A. pascens synthesis and activity of choline oxidase were modulated by carbon sources and were susceptible to catabolite repression. Thus, cox, a gene concerned with carbon utilization in A. pascens, was found to play a role in adaptation to an environmental stress in a heterologous organism. In addition to providing a possible means of manipulating osmotolerance in other organisms, the cox gene offers a model system for the study of choline oxidation, an important metabolic process in both procaryotes and eucaryotes. Images PMID:1987142

  7. Choline acetate enhanced the catalytic performance of Candida rogusa lipase in AOT reverse micelles.

    PubMed

    Xue, Luyan; Zhao, Yin; Yu, Lijie; Sun, Yanwen; Yan, Keqian; Li, Ying; Huang, Xirong; Qu, Yinbo

    2013-05-01

    Choline acetate is an ionic liquid composed of a kosmotropic anion and a chaotropic cation. According to Hofmeister series, a kosmotropic anion and/or a chaotropic cation could stabilize an enzyme, thereby facilitating the retention of the catalytic activity of the enzyme. In this work, we first report the influence of choline acetate on the activity and stability of lipase in AOT/water/isooctane reverse micelles. The indicator reaction is the lipase-catalyzed hydrolysis of 4-nitrophenyl butyrate. The results show that a low level of choline acetate does not affect the microstructure of the AOT reverse micelles, but the ionic liquid can improve the catalytic efficiency of lipase. Fluorescence spectra show that a high level of choline acetate has an impact on the conformation of lipase, so the activation is mainly due to the influence of choline acetate on the nucleophilicity of water. Infrared spectra demonstrate that choline acetate can form stronger hydrogen bonds with water surrounding lipase, and therefore enhance the nucleophilicity of the water, which makes it easier to attack the acyl enzyme intermediate, thereby increasing the activity of the lipase-catalyzed hydrolysis of the ester. A study on the stability of lipase in AOT reverse micelles indicates that the ionic liquid is able to maintain the activity of lipase to a certain extent. The effect of choline acetate is consistent with that predicted based on Hofmeister series. PMID:23352950

  8. Choline supplementation in children with Fetal Alcohol Spectrum Disorders (FASD) has high feasibility and tolerability

    PubMed Central

    Wozniak, Jeffrey R.; Fuglestad, Anita J.; Eckerle, Judith K.; Kroupina, Maria G.; Miller, Neely C.; Boys, Christopher J.; Brearley, Ann M.; Fink, Birgit A.; Hoecker, Heather L.; Zeisel, Steven H.; Georgieff, Michael K.

    2013-01-01

    There are no biological treatments for fetal alcohol spectrum disorders (FASD), lifelong conditions associated with physical anomalies, brain damage, and neurocognitive abnormalities. In pre-clinical studies, choline partially ameliorates memory and learning deficits from prenatal alcohol exposure. This Phase I pilot study evaluated the feasibility, tolerability, and potential adverse effects of choline supplementation in children with FASD. We hypothesized that choline would be well-tolerated with minimal adverse events. The study design was a double-blind, randomized, placebo-controlled trial. Participants included 20 children, ages 2.5–4.9y, with prenatal alcohol exposure and FASD diagnoses. Participants were randomly assigned to 500 mg. choline or placebo daily for nine months (10 active; 10 placebo). Primary outcome measures included feasibility, tolerability, adverse effects, and serum choline levels. Seventeen participants completed the study. Compliance was 82–87% as evidenced by parent-completed logsheets and dose counts. Periodic 24-hour dietary recalls showed no evidence of dietary confounding. Adverse events were minimal and were equivalent in the active and placebo arms with the exception of fishy body odor, which occurred only in the active group. There were no serious adverse events to research participants. This Phase I pilot study demonstrates that choline supplementation at 500 mg per day for nine months in children ages 2–5 is feasible and has high tolerability. Further examination of the efficacy of choline supplementation in FASD is currently underway. PMID:24176229

  9. No Acute Effects of Choline Bitartrate Food Supplements on Memory in Healthy, Young, Human Adults

    PubMed Central

    Lippelt, D. P.; van der Kint, S.; van Herk, K.; Naber, M.

    2016-01-01

    Choline is a dietary component and precursor of acetylcholine, a crucial neurotransmitter for memory-related brain functions. In two double-blind, placebo-controlled cross-over experiments, we investigated whether the food supplement choline bitartrate improved declarative memory and working memory in healthy, young students one to two hours after supplementation. In experiment 1, 28 participants performed a visuospatial working memory task. In experiment 2, 26 participants performed a declarative picture memorization task. In experiment 3, 40 participants performed a verbal working memory task in addition to the visuospatial working memory and declarative picture task. All tasks were conducted approximately 60 minutes after the ingestion of 2.0–2.5g of either choline bitartrate or placebo. We found that choline did not significantly enhance memory performance during any of the tasks. The null hypothesis that choline does not improve memory performance as compared to placebo was strongly supported by Bayesian statistics. These results are in contrast with animal studies suggesting that choline supplementation boosts memory performance and learning. We conclude that choline likely has no acute effects on cholinergic memory functions in healthy human participants. PMID:27341028

  10. No Acute Effects of Choline Bitartrate Food Supplements on Memory in Healthy, Young, Human Adults.

    PubMed

    Lippelt, D P; van der Kint, S; van Herk, K; Naber, M

    2016-01-01

    Choline is a dietary component and precursor of acetylcholine, a crucial neurotransmitter for memory-related brain functions. In two double-blind, placebo-controlled cross-over experiments, we investigated whether the food supplement choline bitartrate improved declarative memory and working memory in healthy, young students one to two hours after supplementation. In experiment 1, 28 participants performed a visuospatial working memory task. In experiment 2, 26 participants performed a declarative picture memorization task. In experiment 3, 40 participants performed a verbal working memory task in addition to the visuospatial working memory and declarative picture task. All tasks were conducted approximately 60 minutes after the ingestion of 2.0-2.5g of either choline bitartrate or placebo. We found that choline did not significantly enhance memory performance during any of the tasks. The null hypothesis that choline does not improve memory performance as compared to placebo was strongly supported by Bayesian statistics. These results are in contrast with animal studies suggesting that choline supplementation boosts memory performance and learning. We conclude that choline likely has no acute effects on cholinergic memory functions in healthy human participants. PMID:27341028

  11. Behavioural effects of chronic manipulations of dietary choline in senescent rats.

    PubMed

    Fundaro, A; Paschero, A

    1990-01-01

    1. Senescent rats were maintained on choline-deficient and choline-enriched diets. The modifications in rat behaviour caused by the chronic manipulations of dietary choline were studied in two schedules of operant conditioning. 2. In the "periodic conditioning" test, the schedule of reinforcement, in a 100 min trial, was changed from a fixed ratio to a fixed interval schedule. In the "reversal" test the contingency for food delivery was switched four times from one lever to the other in a two lever Skinner box. 3. In the "periodic conditioning" test, the choline enriched group (430 mg/Kg/day) showed the same reduction of responses/reinforcement as controls, from the beginning to the end of trial; in the same group the time course reduction of responses/reinforcement became significant earlier than in the control group. The deficient-choline group in the last 40 min of "periodic conditioning" trial gave a reduction of responses/reinforcement greater than controls and one rat in the group did not learn the change of experimental schedule and extinguished its operant behaviour. 4. In the "reversal" test, the choline-enriched diet (320 mg/Kg/day) improved the reinforced responses in the IV reversal; one rat of the deficient-choline group could not learn the new operant schedule since the first reversal and continued to respond on the same lever during the whole of the test. PMID:2277854

  12. A pharmacokinetic comparison of choline magnesium trisalicylate and soluble aspirin.

    PubMed

    Helliwell, M; Gibson, T; Berry, D; Volans, G

    1984-11-01

    Claims that twice-daily dosage of choline magnesium trisalicylate (CMT) may alter salicylate disposal kinetics and result in sustained plasma levels were examined. Plasma levels, urine excretion and pharmacokinetics of salicylate were estimated in six men following the recommended twice-daily dose of CMT and a smaller dose of soluble aspirin. The plasma salicylate levels achieved with CMT were lower than those seen in previous studies but this probably reflected differences of methodology. Salicylate levels were not sustained between doses and elimination rates and half-life were similar for both preparations. No major alteration of disposal kinetics could be demonstrated for CMT with the dose used in the present study. PMID:6487934

  13. Choline requirements of White Pekin ducks from hatch to 21 days of age.

    PubMed

    Wen, Z G; Tang, J; Hou, S S; Guo, Y M; Huang, W; Xie, M

    2014-12-01

    A dose-response experiment with 8 dietary choline levels (302, 496, 778, 990, 1,182, 1,414, 1,625, and 1,832 mg/kg) was conducted with male White Pekin ducks to estimate the choline requirement from hatch to 21 d of age. Three hundred eighty-four 1-d-old male White Pekin ducks were randomly assigned to 8 dietary treatments, each containing 6 replicate pens with 8 birds per pen. At 21 d of age, weight gain, feed intake, and feed/gain from each pen were calculated for feeding period, and 2 ducks selected randomly from each pen were euthanized and the liver was collected to determine total lipids, triglycerides, and phospholipids. In our study, perosis, poor growth, and high liver fat were all observed in choline-deficient ducks and incidence of perosis was zero when dietary choline was 1,182 mg/kg. As dietary choline increased, the weight gain and feed intake increased linearly or quadratically (P < 0.05). On the other hand, as dietary choline increased, the total lipid and triglyceride in liver decreased linearly and liver phospholipid increased linearly (P < 0.05), and the lipotropic activity of choline may be associated with increasing phospholipid at a high dietary choline level. According to broken-line regression, the choline requirements for weight gain and feed intake were 810 and 823 mg/kg, respectively, but higher requirement should be considered to prevent perosis and excess liver lipid deposition completely. PMID:25260528

  14. Molecular Docking and Pharmacological Investigations of Rivastigmine-Fluoxetine and Coumarin–Tacrine hybrids against Acetyl Choline Esterase

    PubMed Central

    Babitha, Pallikkara Pulikkal; Sahila, Mohammed Marunnan; Bandaru, Srinivas; Nayarisseri, Anuraj; Sureshkumar, Sivanpillai

    2015-01-01

    The present AChE inhibitors have been successful in the treatment of Alzheimer׳s Diseases however suffers serious side effects. Therefore in this view, the present study was sought to identify compounds with appreciable pharmacological profile targeting AChE. Analogue of Rivastigmine and Fluoxetine hybrid synthesized by Toda et al, 2003 (dataset1), and Coumarin−Tacrine hybrids synthesized by Qi Sun et al (dataset2) formed the test compounds for the present pharmacological evaluation. p-cholorophenyl substituted Rivastigmine and Fluoxetine hybrid compound (26d) from dataset 1 and −OCH3 substitute Coumarin−Tacrine hybrids (1h) from dataset 2 demonstrated superior pharmacological profile. 26 d showed superior pharmacological profile comparison to the entire compounds in either dataset owing to its better electrostatic interactions and hydrogen bonding patterns. In order to identify still better compound with pharmacological profile than 26 d and 1h, virtual screening was performed. The best docked compound (PubCId: PubCid: 68874404) showed better affinity than its parent 26 d, however showed poor ADME profile and AMES toxicity. CHEMBL2391475 (PubCid: 71699632) similar to 1h had reduced affinity in comparison to its parent compound 1h. From, our extensive analysis involving binding affinity analysis, ADMET properties predictions and pharmacophoric mappings, we report p-cholorophenyl substituted rivastigmine and fluoxetine hybrid (26d) to be a potential candidate for AcHE inhibition which in addition can overcome narrow therapeutic window of present AChE inhibitors in clinical treatment of Alzheimer׳s disease. Abbreviations AD - Alzheimer׳s Disease, AChE - Acetyl Choline Estarase, OPLS - Optimized Potentials for Liquid Simulations, PDB - Protein Data Bank. PMID:26420918

  15. Raising gestational choline intake alters gene expression in DMBA-evoked mammary tumors and prolongs survival

    PubMed Central

    Kovacheva, Vesela P.; Davison, Jessica M.; Mellott, Tiffany J.; Rogers, Adrianne E.; Yang, Shi; O'Brien, Michael J.; Blusztajn, Jan Krzysztof

    2009-01-01

    Choline is an essential nutrient that serves as a donor of metabolic methyl groups used during gestation to establish the epigenetic DNA methylation patterns that modulate tissue-specific gene expression. Because the mammary gland begins its development prenatally, we hypothesized that choline availability in utero may affect the gland’s susceptibility to cancer. During gestational days 11–17, pregnant rats were fed a control, choline-supplemented, or choline-deficient diet (8, 36, and 0 mmol/kg of choline, respectively). On postnatal day 65, the female offspring received 25 mg/kg of a carcinogen 7,12-dimethylbenz[α]anthracene. Approximately 70% of the rats developed mammary adenocarcinomas; prenatal diet did not affect tumor latency, incidence, size, and multiplicity. Tumor growth rate was inversely related to choline content in the prenatal diet, resulting in 50% longer survival until euthanasia, determined by tumor size, of the prenatally choline-supplemented rats compared with the prenatally choline-deficient rats. This was accompanied by distinct expression patterns of ∼70 genes in tumors derived from the three dietary groups. Tumors from the prenatally choline-supplemented rats overexpressed genes that confer favorable prognosis in human cancers (Klf6, Klf9, Nid2, Ntn4, Per1, and Txnip) and underexpressed those associated with aggressive disease (Bcar3, Cldn12, Csf1, Jag1, Lgals3, Lypd3, Nme1, Ptges2, Ptgs1, and Smarcb1). DNA methylation within the tumor suppressor gene, stratifin (Sfn, 14-3-3σ), was proportional to the prenatal choline supply and correlated inversely with the expression of its mRNA and protein in tumors, suggesting that an epigenetic mechanism may underlie the altered molecular phenotype and tumor growth. Our results suggest a role for adequate maternal choline nutrition during pregnancy in prevention/alleviation of breast cancer in daughters.—Kovacheva, V. P., Davison, J. M., Mellott, T. J., Rogers, A. E., Yang, S., O’Brien, M

  16. Intensity Modulated Radiation Therapy Dose Painting for Localized Prostate Cancer Using {sup 11}C-choline Positron Emission Tomography Scans

    SciTech Connect

    Chang, Joe H.; Lim Joon, Daryl; Lee, Sze Ting; Gong, Sylvia J.; Anderson, Nigel J.; Scott, Andrew M.; Davis, Ian D.; Clouston, David; Bolton, Damien; Hamilton, Christopher S.; Khoo, Vincent

    2012-08-01

    Purpose: To demonstrate the technical feasibility of intensity modulated radiation therapy (IMRT) dose painting using {sup 11}C-choline positron emission tomography PET scans in patients with localized prostate cancer. Methods and Materials: This was an RT planning study of 8 patients with prostate cancer who had {sup 11}C-choline PET scans prior to radical prostatectomy. Two contours were semiautomatically generated on the basis of the PET scans for each patient: 60% and 70% of the maximum standardized uptake values (SUV{sub 60%} and SUV{sub 70%}). Three IMRT plans were generated for each patient: PLAN{sub 78}, which consisted of whole-prostate radiation therapy to 78 Gy; PLAN{sub 78-90}, which consisted of whole-prostate RT to 78 Gy, a boost to the SUV{sub 60%} to 84 Gy, and a further boost to the SUV{sub 70%} to 90 Gy; and PLAN{sub 72-90}, which consisted of whole-prostate RT to 72 Gy, a boost to the SUV{sub 60%} to 84 Gy, and a further boost to the SUV{sub 70%} to 90 Gy. The feasibility of these plans was judged by their ability to reach prescription doses while adhering to published dose constraints. Tumor control probabilities based on PET scan-defined volumes (TCP{sub PET}) and on prostatectomy-defined volumes (TCP{sub path}), and rectal normal tissue complication probabilities (NTCP) were compared between the plans. Results: All plans for all patients reached prescription doses while adhering to dose constraints. TCP{sub PET} values for PLAN{sub 78}, PLAN{sub 78-90}, and PLAN{sub 72-90} were 65%, 97%, and 96%, respectively. TCP{sub path} values were 71%, 97%, and 89%, respectively. Both PLAN{sub 78-90} and PLAN{sub 72-90} had significantly higher TCP{sub PET} (P=.002 and .001) and TCP{sub path} (P<.001 and .014) values than PLAN{sub 78}. PLAN{sub 78-90} and PLAN{sub 72-90} were not significantly different in terms of TCP{sub PET} or TCP{sub path}. There were no significant differences in rectal NTCPs between the 3 plans. Conclusions: IMRT dose painting for

  17. Affinity chromatography: a historical perspective.

    PubMed

    Hage, David S; Matsuda, Ryan

    2015-01-01

    Affinity chromatography is one of the most selective and versatile forms of liquid chromatography for the separation or analysis of chemicals in complex mixtures. This method makes use of a biologically related agent as the stationary phase, which provides an affinity column with the ability to bind selectively and reversibly to a given target in a sample. This review examines the early work in this method and various developments that have lead to the current status of this technique. The general principles of affinity chromatography are briefly described as part of this discussion. Past and recent efforts in the generation of new binding agents, supports, and immobilization methods for this method are considered. Various applications of affinity chromatography are also summarized, as well as the influence this field has played in the creation of other affinity-based separation or analysis methods. PMID:25749941

  18. Hepatic Effects of a Methionine-Choline-Deficient Diet in Hepatocyte RXRα-null Mice

    PubMed Central

    Gyamfi, Maxwell Afari; Tanaka, Yuji; He, Lin; Klaassen, Curtis D.; Wan, Yu-Jui Yvonne

    2009-01-01

    Retinoid X receptor-α (RXRα) is an obligate partner for several nuclear hormone receptors that regulate important physiological processes in the liver. In this study the impact of hepatocyte RXRα deficiency on methionine and choline deficient (MCD) diet-induced steatosis, oxidative stress, inflammation, and hepatic transporters gene expression were examined. The mRNA of sterol regulatory element-binding protein (SREBP)-regulated genes, important for lipid synthesis, were not altered in wild type (WT) mice, but were increased 2.0- to 5.4-fold in hepatocyte RXRα-null (H-RXRα-null) mice fed a MCD diet for 14 days. Furthermore, hepatic mRNAs and proteins essential for fatty acid β-oxidation were not altered in WT mice, but were decreased in the MCD diet-fed H-RXRα-null mice, resulting in increased hepatic free fatty acid levels. Cyp2e1 enzyme activity and lipid peroxide levels were induced only in MCD-fed WT mice. In contrast, hepatic mRNA levels of pro-inflammatory factors were increased only in H-RXRα-null mice fed the MCD diet. Hepatic uptake transporters Oatp1a1 and Oatp1b2 mRNA levels were decreased in WT mice fed the MCD diet, whereas the efflux transporter Mrp4 was increased. However, in the H-RXRα-null mice, the MCD diet only moderately decreased Oatp1a1 and induced both Oatp1a4 and Mrp4 gene expression. Whereas the MCD diet increased serum bile acid levels and alkaline phosphatase activity in both WT and H-RXRα-null mice, serum ALT levels were induced (2.9-fold) only in the H-RXRα-null mice. In conclusion, these data suggest a critical role for RXRα in hepatic fatty acid homeostasis and protection against MCD-induced hepatocyte injury. PMID:18952117

  19. Hepatic effects of a methionine-choline-deficient diet in hepatocyte RXR{alpha}-null mice

    SciTech Connect

    Gyamfi, Maxwell Afari; Tanaka, Yuji; He Lin; Klaassen, Curtis D.; Wan, Y.-J.Y.

    2009-01-15

    Retinoid X receptor-{alpha} (RXR{alpha}) is an obligate partner for several nuclear hormone receptors that regulate important physiological processes in the liver. In this study the impact of hepatocyte RXR{alpha} deficiency on methionine and choline deficient (MCD) diet-induced steatosis, oxidative stress, inflammation, and hepatic transporters gene expression were examined. The mRNA of sterol regulatory element-binding protein (SREBP)-regulated genes, important for lipid synthesis, were not altered in wild type (WT) mice, but were increased 2.0- to 5.4-fold in hepatocyte RXR{alpha}-null (H-RXR{alpha}-null) mice fed a MCD diet for 14 days. Furthermore, hepatic mRNAs and proteins essential for fatty acid {beta}-oxidation were not altered in WT mice, but were decreased in the MCD diet-fed H-RXR{alpha}-null mice, resulting in increased hepatic free fatty acid levels. Cyp2e1 enzyme activity and lipid peroxide levels were induced only in MCD-fed WT mice. In contrast, hepatic mRNA levels of pro-inflammatory factors were increased only in H-RXR{alpha}-null mice fed the MCD diet. Hepatic uptake transporters Oatp1a1 and Oatp1b2 mRNA levels were decreased in WT mice fed the MCD diet, whereas the efflux transporter Mrp4 was increased. However, in the H-RXR{alpha}-null mice, the MCD diet only moderately decreased Oatp1a1 and induced both Oatp1a4 and Mrp4 gene expression. Whereas the MCD diet increased serum bile acid levels and alkaline phosphatase activity in both WT and H-RXR{alpha}-null mice, serum ALT levels were induced (2.9-fold) only in the H-RXR{alpha}-null mice. In conclusion, these data suggest a critical role for RXR{alpha} in hepatic fatty acid homeostasis and protection against MCD-induced hepatocyte injury.

  20. Rational stabilization of the C-LytA affinity tag by protein engineering.

    PubMed

    Hernández-Rocamora, Víctor M; Maestro, Beatriz; Mollá-Morales, Almudena; Sanz, Jesús M

    2008-12-01

    The C-LytA protein constitutes the choline-binding module of the LytA amidase from Streptococcus pneumoniae. Owing to its affinity for choline and analogs, it is regularly used as an affinity tag for the purification of proteins in a single chromatographic step. In an attempt to build a robust variant against thermal denaturation, we have engineered several salt bridges on the protein surface. All the stabilizing mutations were pooled in a single variant, C-LytAm7, which contained seven changes: Y25K, F27K, M33E, N51K, S52K, T85K and T108K. The mutant displays a 7 degrees C thermal stabilization compared with the wild-type form, together with a complete reversibility upon heating and a higher kinetic stability. Moreover, the accumulation of intermediates in the unfolding of C-LytA is virtually abolished for C-LytAm7. The differences in stability become more evident when the proteins are bound to a DEAE-cellulose affinity column, as most of wild-type C-LytA is denatured at approximately 65 degrees C, whereas C-LytAm7 may stand temperatures up to 90 degrees C. Finally, the change in the isoelectric point of C-LytAm7 enhances its solubility at acidic pHs. Therefore, C-LytAm7 behaves as an improved affinity tag and supports the engineering of surface salt bridges as an effective approach for protein stabilization. PMID:18840883

  1. MTHFR C677T genotype influences the isotopic enrichment of one-carbon metabolites in folate-compromised men consuming d9-choline123

    PubMed Central

    Yan, Jian; Wang, Wei; Gregory, Jesse F; Malysheva, Olga; Brenna, J Thomas; Stabler, Sally P; Allen, Robert H; Caudill, Marie A

    2011-01-01

    Background: Homozygosity for the variant 677T allele in the methylenetetrahydrofolate reductase (MTHFR) gene increases the requirement for folate and may alter the metabolic use of choline. The choline adequate intake is 550 mg/d for men, although the metabolic consequences of consuming extra choline are unclear. Objective: Deuterium-labeled choline (d9-choline) as tracer was used to determine the differential effects of the MTHFR C677T genotype and the effect of various choline intakes on the isotopic enrichment of choline derivatives in folate-compromised men. Design: Mexican American men with the MTHFR 677CC or 677TT genotype consumed a diet providing 300 mg choline/d plus supplemental choline chloride for total choline intakes of 550 (n = 11; 4 with 677CC and 7 with 677TT) or 1100 (n = 12; 4 with 677CC and 8 with 677TT) mg/d for 12 wk. During the last 3 wk, 15% of the total choline intake was provided as d9-choline. Results: Low but measurable enrichments of the choline metabolites were achieved, including that of d3-phosphatidylcholine (d3-PtdCho)—a metabolite produced in the de novo pathway via choline-derived methyl groups. Men with the MTHFR 677TT genotype had a higher urinary enrichment ratio of betaine to choline (P = 0.041), a higher urinary enrichment of sarcosine (P = 0.041), and a greater plasma enrichment ratio of d9-betaine to d9-PtdCho with the 1100 mg choline/d intake (P = 0.033). Conclusion: These data show for the first time in humans that choline itself is a source of methyl groups for de novo PtdCho biosynthesis and indicate that the MTHFR 677TT genotype favors the use of choline as a methyl donor. PMID:21123458

  2. Methionine and choline regulate the metabolic phenotype of a ketogenic diet.

    PubMed

    Pissios, Pavlos; Hong, Shangyu; Kennedy, Adam Richard; Prasad, Deepthi; Liu, Fen-Fen; Maratos-Flier, Eleftheria

    2013-01-01

    Low-carbohydrate ketogenic diets are commonly used as weight loss alternatives to low-fat diets, however the physiological and molecular adaptations to these diets are not completely understood. It is assumed that the metabolic phenotype of the ketogenic diet (KD) is caused by the absence of carbohydrate and high fat content, however in rodents the protein content of KD affects weight gain and ketosis. In this study we examined the role of methionine and choline in mediating the metabolic effects of KD. We have found that choline was more effective than methionine in decreasing the liver steatosis of KD-fed mice. On the other hand, methionine supplementation was more effective than choline in restoring weight gain and normalizing the expression of several fatty acid and inflammatory genes in the liver of KD-fed mice. Our results indicate that choline and methionine restriction rather than carbohydrate restriction underlies many of the metabolic effects of KD. PMID:24049742

  3. Formulation and utilization of choline based samples for dissolution dynamic nuclear polarization

    NASA Astrophysics Data System (ADS)

    Bowen, Sean; Ardenkjaer-Larsen, Jan Henrik

    2013-11-01

    Hyperpolarization by the dissolution dynamic nuclear polarization (DNP) technique permits the generation of high spin polarization of solution state. However, sample formulation for dissolution-DNP is often difficult, as concentration and viscosity must be optimized to yield a dissolved sample with sufficient concentration, while maintaining polarization during the dissolution process. The unique chemical properties of choline permit the generation of highly soluble salts as well as deep eutectic mixtures with carboxylic acids and urea. We describe the formulation of these samples and compare their performance to more traditional sample formulations. Choline yields stable samples with exceptional polarization performance while simultaneously offering the capability to easily remove the choline after dissolution, perform experiments with the hyperpolarized choline, or anything in between.

  4. Choline metabolism as a basis for the selective vulnerability of cholinergic neurons

    NASA Technical Reports Server (NTRS)

    Wurtman, R. J.

    1992-01-01

    The unique propensity of cholinergic neurons to use choline for two purposes--ACh and membrane phosphatidylcholine synthesis--may contribute to their selective vulnerability in Alzheimer's disease and other cholinergic neurodegenerative disorders. When physiologically active, the neurons use free choline taken from the 'reservoir' in membrane phosphatidylcholine to synthesize ACh; this can lead to an actual decrease in the quantity of membrane per cell. Alzheimer's disease (but not Down's syndrome, or other neurodegenerative disorders) is associated with characteristic neurochemical lesions involving choline and ethanolamine: brain levels of these compounds are diminished, while those of glycerophosphocholine and glycerophosphoethanolamine (breakdown products of their respective membrane phosphatides) are increased, both in cholinergic and noncholinergic brain regions. Perhaps this metabolic disturbance and the tendency of cholinergic neurons to 'export' choline--in the form of ACh--underlie the selective vulnerability of the neurons. Resulting changes in membrane composition could abnormally expose intramembraneous proteins such as amyloid precursor protein to proteases.

  5. Transcriptional regulation of methionine synthase by homocysteine and choline in Aspergillus nidulans.

    PubMed Central

    Kacprzak, Magdalena M; Lewandowska, Irmina; Matthews, Rowena G; Paszewski, Andrzej

    2003-01-01

    Roles played by homocysteine and choline in the regulation of MS (methionine synthase) have been examined in fungi. The Aspergillus nidulans metH gene encoding MS was cloned and characterized. Its transcription was not regulated by methionine, but was enhanced by homocysteine and repressed by choline and betaine. MS activity levels were regulated in a similar way. The repression by betaine was due to its metabolic conversion to choline, which was found to be very efficient in A. nidulans. Betaine and choline supplementation stimulated growth of leaky metH mutants apparently by decreasing the demand for methyl groups and thus saving methionine and S -adenosylmethionine. We have also found that homocysteine stimulates transcription of MS-encoding genes in Saccharomyces cerevisiae and Schizosaccharomyces pombe. PMID:12954077

  6. Cellular uptake of metallated cobalamins.

    PubMed

    Tran, Mai Thanh Quynh; Stürup, Stefan; Lambert, Ian Henry; Gammelgaard, Bente; Furger, Evelyne; Alberto, Roger

    2016-03-16

    Cellular uptake of vitamin B12-cisplatin conjugates was estimated via detection of their metal constituents (Co, Pt, and Re) by inductively coupled plasma mass spectrometry (ICP-MS). Vitamin B12 (cyano-cob(iii)alamin) and aquo-cob(iii)alamin [Cbl-OH2](+), which differ in the β-axial ligands (CN(-) and H2O, respectively), were included as control samples. The results indicated that B12 derivatives delivered cisplatin to both cellular cytosol and nuclei with an efficiency of one third compared to the uptake of free cisplatin cis-[Pt(II)Cl2(NH3)2]. In addition, uptake of charged B12 derivatives including [Cbl-OH2](+), [{Co}-CN-{cis-PtCl(NH3)2}](+), [{Re}-{Co}-CN-{cis-PtCl(NH3)2}](+), and [{Co}-CN-{trans-Pt(Cyt)(NH3)2}](2+) (Cyt = cytarabin) was high compared to neutral B12, which implied the existence of an additional internalization pathway for charged B12 vitamin analogs. The affinities of the charged B12 derivatives to the B12 transporters HC, IF and TC were similar to that of native vitamin B12. PMID:26739575

  7. [Diagnostic relevance of choline-PET / CT in patients with prostate cancer].

    PubMed

    Zengerling, F; Schrader, A J; Schrader, M; Jentzmik, F

    2012-01-01

    The choline-positron emissiontomography / computed tomography (choline-PET / CT) is a widely used imaging method for prostate cancer. This review concentrates on the relevance of choline-PET / CT for primary diagnosis, staging and re-staging of prostate cancer and highlights possible -applications in clinical practice. Therefore, we performed a systematic literature research via Pubmed and Medline database for original articles, reviews and editorials on choline-PET / CT and prostate cancer. Choline-PET / CT should not be routinely used for primary diagnosis of prostate cancer due to a lack of data. With regard to the definition of the local tumour extent (T-stag-ing) choline-PET / CT plays only a minor role, in contrast, for the evaluation of lymph node involvement it has a high positive predictive value and is equal to conventional scintigraphy in detecting bone metastases. Moreover, in cases of biochemical relapse following local therapy, choline-PET / CT seems to be appropriate for differentiating between local recurrence and systemic prostate cancer metastasis, particularly when patients are selected by defined criteria (PSA value > 1.0  ng / mL and / or PSAdt < 6  months and / or Gleason score > 7 and / or primary radiotherapy). The non-critical routine use of choline-PET / CT for patients with prostate cancer cannot be recommended, and this not only because of its high costs. It should be applied to definite clinical questions after thorough selection of appropriate patients. PMID:21769763

  8. Choline and betaine intakes are associated with reduced risk of nasopharyngeal carcinoma in adults: a case–control study

    PubMed Central

    Zeng, F-f; Xu, C-h; Liu, Y-t; Fan, Y-y; Lin, X-l; Lu, Y-k; Zhang, C-x; Chen, Y-m

    2014-01-01

    Background: Intakes of choline and betaine have been inversely related to the risk of various neoplasms, but scant data exist on nasopharyngeal carcinoma (NPC). We examined the association between consumption of choline and betaine and risk of NPC. Methods: We conducted a case–control study with 600 incident NPC patients and 600 controls 1 : 1 matched by age, sex and household type in Guangdong, China. Dietary intake was assessed by a food frequency questionnaire through face-to-face interview. Results: Intakes of total choline, betaine and choline+betaine were inversely related to NPC after adjustment for various lifestyle and dietary factors (all P-trend <0.001). Adjusted odds ratios (95% CI) for quartile 4 (vs quartile 1) were 0.42 (0.29, 0.61) for total choline, 0.50 (0.35, 0.72) for betaine and 0.44 (0.30, 0.64) for betaine+total choline. Regarding various sources of choline, lower NPC risk was associated with greater intakes of choline from phosphatidylcholine, free choline, glycerophosphocholine and phosphocholine, but not sphingomyelin. Conclusion: These findings are consistent with a beneficial effect of choline and betaine intakes on carcinogenesis. PMID:24169354

  9. Prenatal choline supplementation attenuates spatial learning deficits of offspring rats exposed to low-protein diet during fetal period.

    PubMed

    Zhu, Cui-Hong; Wu, Ting; Jin, Yu; Huang, Bi-Xia; Zhou, Rui-Fen; Wang, Yi-Qin; Luo, Xiao-Lin; Zhu, Hui-Lian

    2016-06-01

    Prenatal intake of choline has been reported to lead to enhanced cognitive function in offspring, but little is known about the effects on spatial learning deficits. The present study examined the effects of prenatal choline supplementation on developmental low-protein exposure and its potential mechanisms. Pregnant female rats were fed either a normal or low-protein diet containing sufficient choline (1.1g/kg choline chloride) or supplemented choline (5.0g/kg choline chloride) until delivery. The Barnes maze test was performed at postnatal days 31-37. Choline and its metabolites, the synaptic structural parameters of the CA1 region in the brain of the newborn rat, were measured. The Barnes maze test demonstrated that prenatal low-protein pups had significantly greater error scale values, hole deviation scores, strategy scores and spatial search strategy and had lesser random search strategy values than normal protein pups (all P<.05). These alterations were significantly reversed by choline supplementation. Choline supplementation increased the brain levels of choline, betaine, phosphatidylethanolamine and phosphatidylcholine of newborns by 51.35% (P<.05), 33.33% (P<.001), 28.68% (P<.01) and 23.58% (P<.05), respectively, compared with the LPD group. Prenatal choline supplementation reversed the increased width of the synaptic cleft (P<.05) and decreased the curvature of the synaptic interface (P<.05) induced by a low-protein diet. Prenatal choline supplementation could attenuate the spatial learning deficits caused by prenatal protein malnutrition by increasing brain choline, betaine and phospholipids and by influencing the hippocampus structure. PMID:27142732

  10. Evidence for negative selection of gene variants that increase dependence on dietary choline in a Gambian cohort

    PubMed Central

    Silver, Matt J.; Corbin, Karen D.; Hellenthal, Garrett; da Costa, Kerry-Ann; Dominguez-Salas, Paula; Moore, Sophie E.; Owen, Jennifer; Prentice, Andrew M.; Hennig, Branwen J.; Zeisel, Steven H.

    2015-01-01

    Choline is an essential nutrient, and the amount needed in the diet is modulated by several factors. Given geographical differences in dietary choline intake and disparate frequencies of single-nucleotide polymorphisms (SNPs) in choline metabolism genes between ethnic groups, we tested the hypothesis that 3 SNPs that increase dependence on dietary choline would be under negative selection pressure in settings where choline intake is low: choline dehydrogenase (CHDH) rs12676, methylenetetrahydrofolate reductase 1 (MTHFD1) rs2236225, and phosphatidylethanolamine-N-methyltransferase (PEMT) rs12325817. Evidence of negative selection was assessed in 2 populations: one in The Gambia, West Africa, where there is historic evidence of a choline-poor diet, and the other in the United States, with a comparatively choline-rich diet. We used 2 independent methods, and confirmation of our hypothesis was sought via a comparison with SNP data from the Maasai, an East African population with a genetic background similar to that of Gambians but with a traditional diet that is higher in choline. Our results show that frequencies of SNPs known to increase dependence on dietary choline are significantly reduced in the low-choline setting of The Gambia. Our findings suggest that adequate intake levels of choline may have to be reevaluated in different ethnic groups and highlight a possible approach for identifying novel functional SNPs under the influence of dietary selective pressure.—Silver, M. J., Corbin, K. D., Hellenthal, G., da Costa, K.-A., Dominguez-Salas, P., Moore, S. E., Owen, J., Prentice, A. M., Hennig, B. J., Zeisel, S. H. Evidence for negative selection of gene variants that increase dependence on dietary choline in a Gambian cohort. PMID:25921832

  11. Choline and N,N-Dimethylethanolamine as Direct Substrates for Methanogens

    PubMed Central

    Watkins, Andrew J.; Roussel, Erwan G.; Webster, Gordon; Parkes, R. John

    2012-01-01

    Choline (N,N,N-trimethylethanolamine), which is widely distributed in membrane lipids and is a component of sediment biota, has been shown to be utilized anaerobically by mixed prokaryote cultures to produce methane but not by pure cultures of methanogens. Here, we show that five recently isolated Methanococcoides strains from a range of sediments (Aarhus Bay, Denmark; Severn Estuary mudflats at Portishead, United Kingdom; Darwin Mud Volcano, Gulf of Cadiz; Napoli mud volcano, eastern Mediterranean) can directly utilize choline for methanogenesis producing ethanolamine, which is not further metabolized. Di- and monomethylethanolamine are metabolic intermediates that temporarily accumulate. Consistent with this, dimethylethanolamine was shown to be another new growth substrate, but monomethylethanolamine was not. The specific methanogen inhibitor 2-bromoethanesulfonate (BES) inhibited methane production from choline. When choline and trimethylamine are provided together, diauxic growth occurs, with trimethylamine being utilized first, and then after a lag (∼7 days) choline is metabolized. Three type strains of Methanococcoides (M. methylutens, M. burtonii, and M. alaskense), in contrast, did not utilize choline. However, two of them (M. methylutens and M. burtonii) did metabolize dimethylethanolamine. These results extend the known substrates that can be directly utilized by some methanogens, giving them the advantage that they would not be reliant on bacterial syntrophs for their substrate supply. PMID:23001649

  12. Quantum Chemical Insight into the Interactions and Thermodynamics Present in Choline Chloride Based Deep Eutectic Solvents.

    PubMed

    Wagle, Durgesh V; Deakyne, Carol A; Baker, Gary A

    2016-07-14

    We report quantum chemical calculations performed on three popular deep eutectic solvents (DESs) in order to elucidate the molecular interactions, charge transfer interactions, and thermodynamics associated with these systems. The DESs studied comprise 1:2 choline chloride/urea (reline), 1:2 choline chloride/ethylene glycol (ethaline), and 1:1 choline chloride/malonic acid (maloline). The excellent correlation between calculated and experimental vibrational spectra allowed for identification of dominant interactions in the DES systems. The DESs were found to be stabilized by both conventional hydrogen bonds and C-H···O/C-H···π interactions between the components. The hydrogen-bonding network established in the DES is clearly distinct from that which exists within the neat hydrogen-bond donor dimer. Charge decomposition analysis indicates significant charge transfer from choline and chloride to the hydrogen-bond donor with a higher contribution from the cation, and a density of states analysis confirms the direction of the charge transfer. Consequently, the sum of the bond orders of the choline-Cl(-) interactions in the DESs correlates directly with the melting temperatures of the DESs, a correlation that offers insight into the effect of the tuning of the choline-Cl(-) interactions by the hydrogen-bond donors on the physical properties of the DESs. Finally, the differences in the vibrational entropy changes upon DES formation are consistent with the trend in the overall entropy changes upon DES formation. PMID:27268431

  13. Choline chloride-thiourea, a deep eutectic solvent for the production of chitin nanofibers.

    PubMed

    Mukesh, Chandrakant; Mondal, Dibyendu; Sharma, Mukesh; Prasad, Kamalesh

    2014-03-15

    Deep eutectic solvents (DESs) consisting of the mixtures of choline halide (chloride/bromide)-urea and choline chloride-thiourea were used as solvents to prepare α-chitin nanofibers (CNFs). CNFs of diameter 20-30 nm could be obtained using the DESs comprising of the mixture of choline chloride and thiourea (CCT 1:2); however, NFs could not be obtained using the DESs having urea (CCU 1:2) as hydrogen bond donor. The physicochemical properties of thus obtained NFs were compared with those obtained using a couple of imidazolium based ionic liquids namely, 1-butyl-3-methylimidazolium hydrogen sulphate [(Bmim)HSO4] and 1-methylimidazolium hydrogen sulphate [(Hmim)HSO4] as well as choline based bio-ILs namely, choline hydrogen sulphate [(Chol)HSO4] and choline acrylate. The CNFs obtained using the DES as a solvent were used to prepare calcium alginate bio-nanocomposite gel beads having enhanced elasticity in comparison to Ca-alginate beads. The bio-nanocomposite gel beads thus obtained were used to study slow release of 5-fluorouracil, an anticancer drug. PMID:24528755

  14. Oxidative damage lipid peroxidation in the kidney of choline-deficient rats.

    PubMed

    Ossani, Georgina; Dalghi, Marianela; Repetto, Marisa

    2007-01-01

    Phosphatidylcholine is the most abundant phospholipid constituent of cell membranes and choline is a quaternary amine required for phosphatidylcholine synthesis. The impairment of membrane functions is considered as an indication of oxidative damage. In order to kinetically analyze the time course of the pathogenesis of renal necrosis following to choline deficiency in weanling rats, we determined markers of membrane lipid peroxidation (thiobarbituric acid reactive substances; TBARS and hydroperoxide-induced chemiluminescence (BOOH-CL) ) and studied the histopathological damage. Plasma TBARS (t(1/2) = 2.5 days) was an early indicator of systemic oxidative stress, likely involving liver and kidney. The levels of TBARS an BOOH-CL increased by 80% and by 183%, respectively, in kidney homogenates with t(1/2) = 1.5 days and 4 days, respectively. The levels of BOOH-CL were statistically higher in rats fed a choline-deficient diet at day 6, in a mixture of membranes (from plasmatic, smooth and rough endoplasmic reticulum and Golgi), in mitochondrial membranes and in lysosomal membranes. The results indicate that choline deficiency produces oxidative damage in kidney subcellular membranes. Necrosis involved mainly convoluted tubules and appeared with a t(1/2) = 5.5 days. An increase in the production of reactive oxygen species, triggered by NADH overproduction in the mitochondrial dysfunction associated with choline deficiency appears as one of the pathogenic mechanism of mitochondrial and cellular oxidative damage in choline-deficiency. PMID:17127370

  15. Role of Teichoic Acid Choline Moieties in the Virulence of Streptococcus pneumoniae▿

    PubMed Central

    Gehre, Florian; Spisek, Radek; Kharat, Arun S.; Matthews, Phillip; Kukreja, Anjli; Anthony, Robert M.; Dhodapkar, Madhav V.; Vollmer, Waldemar; Tomasz, Alexander

    2009-01-01

    In recent reports it was shown that genetically modified choline-free strains of Streptococcus pneumoniae (D39Cho−licA64 and D39ChiplicB31) expressing the type II capsular polysaccharide were virtually avirulent in the murine sepsis model, in sharp contrast to the isogenic and highly virulent strains D39Cho− and D39Chip, which have retained the choline residues at their surface. We now demonstrate that this choline-associated virulence is independent of Toll-like receptor 2 recognition. Also, despite the lack of virulence, choline-free strains of S. pneumoniae were able to activate splenic dendritic cells, induce secretion of proinflammatory cytokines, and produce specific protective immunity against subsequent challenge. However, after this transient engagement of the immune system the choline-free bacteria were rapidly cleared from the blood, while the isogenic virulent strain D39Cho− continued to grow, accompanied by prolonged expression of cytokines, eventually killing the experimental animals. The critical contribution of choline residues to the virulence potential of pneumococci appears to be the role that these amino alcohol residues play in a pneumococcal immune evasion strategy, the mechanism of which is unknown at the present time. PMID:19433549

  16. Effect of CDP-choline on learning and memory processes in rodents.

    PubMed

    Petkov, V D; Mosharrof, A H; Kehayov, R; Petkov, V V; Konstantinova, E; Getova, D

    1992-10-01

    The effects of cytidine (5') diphosphocholine (CDP-choline) on learning and memory were studied using conditioned reflex methods for passive avoidance and active avoidance with punishment reinforcement (step-through, step-down, shuttle box and maze), for active avoidance with alimentary reinforcement (staircase maze), and the Morris water maze. The majority of experiments involved comparative studies of the nootropic drugs meclofenoxate and/or piracetam. CDP-choline was administered orally, in some of the experiments also intraperitoneally, at doses of 10-500 mg/kg body weight once or twice daily for 5 or 7 days. In separate cases only single doses were administered. Trainings started one hour after the last dose of the drugs. Retention tests were given 3 h, 24 h, 7 days or 10 days after training. The results obtained with the different methods document CDP-choline's ability to improve learning and memory in rats and mice. No essential differences in the effects of CDP-choline were established upon oral and intraperitoneal administration of the drug. The learning- and memory-facilitating effects of CDP-choline were similar to those of meclofenoxate and piracetam. The results of the present study permit us to define CDP-choline as a substance capable of improving cognitive levels. PMID:1494300

  17. Choline requirements of male White Pekin ducks from 21 to 42 d of age.

    PubMed

    Wen, Z G; Hou, S S; Tang, J; Feng, Y L; Huang, W; Guo, Y M; Xie, M

    2014-01-01

    1. A dose-response experiment with 6 dietary choline concentrations (0, 342, 779, 1285, 1662 and 1962 mg/kg) was conducted with male White Pekin ducks to estimate the choline requirement from 21 to 42 d of age. 2. Ninety 21-d-old male White Pekin ducks were allotted to 6 dietary treatments, each containing 5 replicate pens with three birds per pen. At 42 d of age, final weight, weight gain, feed intake and feed/gain were measured. Liver was collected to determine total liver lipid, triglyceride and phospholipids. 3. Significant positive effects of dietary choline on final weight, weight gain and feed intake were observed. In addition, dietary choline supplementation significantly decreased liver lipid and triglyceride content and increased liver phospholipids of Pekin ducks. 4. According to broken-line regression analysis, the choline requirements of male White Pekin ducks from 21 to 42 d of age for weight gain, feed intake and total liver lipid were 980, 950 and 1130 mg/kg. Pekin ducks needed more choline to prevent excess liver lipid deposition than to maintain growth. PMID:25005232

  18. Choline and N,N-dimethylethanolamine as direct substrates for methanogens.

    PubMed

    Watkins, Andrew J; Roussel, Erwan G; Webster, Gordon; Parkes, R John; Sass, Henrik

    2012-12-01

    Choline (N,N,N-trimethylethanolamine), which is widely distributed in membrane lipids and is a component of sediment biota, has been shown to be utilized anaerobically by mixed prokaryote cultures to produce methane but not by pure cultures of methanogens. Here, we show that five recently isolated Methanococcoides strains from a range of sediments (Aarhus Bay, Denmark; Severn Estuary mudflats at Portishead, United Kingdom; Darwin Mud Volcano, Gulf of Cadiz; Napoli mud volcano, eastern Mediterranean) can directly utilize choline for methanogenesis producing ethanolamine, which is not further metabolized. Di- and monomethylethanolamine are metabolic intermediates that temporarily accumulate. Consistent with this, dimethylethanolamine was shown to be another new growth substrate, but monomethylethanolamine was not. The specific methanogen inhibitor 2-bromoethanesulfonate (BES) inhibited methane production from choline. When choline and trimethylamine are provided together, diauxic growth occurs, with trimethylamine being utilized first, and then after a lag (∼7 days) choline is metabolized. Three type strains of Methanococcoides (M. methylutens, M. burtonii, and M. alaskense), in contrast, did not utilize choline. However, two of them (M. methylutens and M. burtonii) did metabolize dimethylethanolamine. These results extend the known substrates that can be directly utilized by some methanogens, giving them the advantage that they would not be reliant on bacterial syntrophs for their substrate supply. PMID:23001649

  19. Affinities of methylphenidate derivatives for dopamine, norepinephrine and serotonin transporters.

    PubMed

    Gatley, S J; Pan, D; Chen, R; Chaturvedi, G; Ding, Y S

    1996-01-01

    We have synthesized several derivative of dl-threo-methylphenidate (Ritalin) bearing substituents on the phenyl ring. IC50 values for binding these compounds to rat brain monoamine transporters were assessed using [3H]WIN 35,428 (striatal membranes, dopamine transporters, DAT), [3H]nisoxetine (frontal cortex membranes, norepinephrine transporters, NET) and [3H]paroxetine (brain stem membranes, 5HT transporters, 5HTT). Affinities (1/Ki) decreased in the order: DAT > NET > 5HTT. Substitution at the para position of dl-threo-methylphenidate generally led to retained or increased affinity for the dopamine transporter (bromo > iodo > methoxy > hydroxy). Substitution at the meta position also increased affinity for the DAT (m-bromo > methylphenidate; m-iodo-p-hydroxy > p-hydroxy). Substitution at the ortho position with bromine considerably decreased affinity. Similar IC50 values for binding of o-bromomethylphenidate to the dopamine transporter were measured at 0, 22 and 37 degrees. N-Methylation of the piperidine ring of methylphenidate also considerably reduced affinity. The dl-erythro isomer of o-bromomethylphenidate did not bind to the DAT (IC50 > 50,000 nM). Affinities at the dopamine and norepinephrine transporters for substituted methylphenidate derivatives were well correlated (r2=0.90). Abilities of several methylphenidate derivatives to inhibit [3H]dopamine uptake in striatal synaptosomes corresponded well with inhibition of [3H]WIN 35, 428 binding. None of the compounds examined exhibited significant affinity to dopamine D1 or D2 receptors (IC50 > 500 or 5,000 nM, respectively), as assessed by inhibition of binding of [3H]SCH 23390 or [123I]epidepride, respectively, to striatal membranes. PMID:8786705

  20. PET/CT in prostate cancer: non-choline radiopharmaceuticals

    PubMed Central

    CASTELLUCCI, P.; JADVAR, H.

    2012-01-01

    In this brief review, the major potential clinical applications of 18F-FDG, 11C-acetate, 18F-FDHT, 18F-FLT, 18F-FMAU, and anti-18F-FACBC in the imaging evaluation of men with prostate cancer are discussed. 18F-FDG has a limited role in primary diagnosis and staging but it may be able to reflect tumour aggressiveness, detect sites of recurrence in some men with high serum PSA after biochemical failure and assess response to chemo- and hormonal treatment in metastatic disease. 11C-acetate has been investigated for intra-prostatic primary tumour detection and staging as well as for re-staging in case of biochemical relapse with results that are overall similar to those with 18F- and 11C-labeled choline. 18F-FDHT targets the androgen receptor and may be particularly useful in the assessment of the pharmacodynamics of the androgen signalling pathway. PET in conjunction with 18F-FLT or 18F-FMAU that track the thymidine salvage pathway of DNA synthesis has also been investigated for imaging cellular proliferation in prostate cancer. Initial exprience with the radiolabeked synthetic amino acid, anti-18F-FACBC, which displays slow urinary excretion has been encouraging but further studies will be needed to decipher its exact role in the imaging management of men with prostate cancer. PMID:23013666

  1. Electrostatic Forces Mediated by Choline Dihydrogen Phosphate Stabilize Collagen.

    PubMed

    Mehta, Ami; Rao, J Raghava; Fathima, N Nishad

    2015-10-01

    Cross-linkers aid in improving biostability of collagen via different mechanisms. Choline dihydrogen phosphate (cDHP), a biocompatible ionic liquid, has been reported as a potential cross-linker for collagen. However, its mechanism is yet unclear. This study explores the effect of cDHP on the physicochemical stability of collagen and nature of its interaction. Dielectric behavior of collagen-cDHP composites signifies that cDHP enhances intermolecular forces. This was demonstrated by an increase in cross-linked groups and high denaturation temperature of collagen-cDHP composites. XRD measurements reveal minor conformational change in helices. Molecular modeling studies illustrate that the force existing between collagen and cDHP is electrostatic in nature. Herein, it is postulated that dihydrogen phosphate anion attaches to cationic functional groups of collagen, resulting in closer vicinity of various side chains of collagen, forming physical and chemical cross-links within collagen, contributing to its structural stability. Our study suggests that dihydrogen phosphate anions can be employed for developing a new class of biocompatible cross-linkers. PMID:26388068

  2. Facile pulping of lignocellulosic biomass using choline acetate.

    PubMed

    Cheng, Fangchao; Wang, Hui; Chatel, Gregory; Gurau, Gabriela; Rogers, Robin D

    2014-07-01

    Treating ground bagasse or Southern yellow pine in the biodegradable ionic liquid (IL), choline acetate ([Cho][OAc]), at 100°C for 24h led to dissolution of hemicellulose and lignin, while leaving the cellulose pulp undissolved, with a 54.3% (bagasse) or 34.3% (pine) reduction in lignin content. The IL solution of the dissolved biopolymers can be separated from the undissolved particles either by addition of water (20 wt% of IL) followed by filtration or by centrifugation. Hemicellulose (19.0 wt% of original bagasse, 10.2 wt% of original pine, containing 14-18 wt% lignin) and lignin (5.0 wt% of original bagasse, 6.0 wt% of original pine) could be subsequently precipitated. The pulp obtained from [Cho][OAc] treatment can be rapidly dissolved in 1-ethyl-3-methylimidazolium acetate (e.g., 17 h for raw bagasse vs. 7h for pulp), and precipitated as cellulose-rich material (CRM) with a lower lignin content (e.g., 23.6% for raw bagasse vs. 10.6% for CRM). PMID:24874879

  3. Saltatory conduction precedes remyelination in axons demyelinated with lysophosphatidyl choline.

    PubMed

    Smith, K J; Bostock, H; Hall, S M

    1982-04-01

    The changing electrical and morphological properties of demyelinating and remyelinating nerve fibres have been studied in rat ventral roots after intrathecal injection of lysophosphatidyl choline (LPC). The spatial distribution of electrical excitability within the lesion has been studied in undissected single fibres using high-resolution longitudinal current analysis. The distribution of excitability has been correlated with the ultrastructure of the fibres and with the distribution of the surrounding Schwann cells. Demyelinated axolemma was initially not excited, but conduction across demyelinated internodes appeared progressively from the 4th day after LPC injection. Conduction was never continuous, but proceeded via new foci of inward membrane current as early as 4 days after LPC injection, i.e. 3 days before the onset of remyelination. It is suggested that these foci (termed phi-nodes to distinguish them from the nodes of Ranvier distributed along myelinated nerve fibres) are precursors of nodes of Ranvier, and may indicate aggregates of sodium channels which form along the demyelinated axolemma prior to remyelination. PMID:6804606

  4. Tailor-Made pH-Responsive Poly(choline phosphate) Prodrug as a Drug Delivery System for Rapid Cellular Internalization.

    PubMed

    Wang, Wenliang; Wang, Bo; Ma, Xiaojing; Liu, Sanrong; Shang, Xudong; Yu, Xifei

    2016-06-13

    Rapid cellular uptake and efficient drug release in tumor cells are two of the major challenges for cancer therapy. Herein, we designed and synthesized a novel pH-responsive polymer-drug conjugate system poly(2-(methacryloyloxy)ethyl choline phosphate)-b-poly(2-methoxy-2-oxoethyl methacrylate-hydrazide-doxorubicin) (PCP-Dox) to overcome these two challenges simultaneously. It has been proved that PCP-Dox can be easily and rapidly internalized by various cancer cells due to the strong interaction between multivalent choline phosphate (CP) groups and cell membranes. Furthermore, Dox, linked to the polymer carrier via acid-labile hydrazone bond, can be released from carriers due to the increased acidity in lysosome/endosome (pH 5.0-5.5) after the polymer prodrug was internalized into the cancer cells. The cell viability assay demonstrated that this novel polymer prodrug has shown enhanced cytotoxicity in various cancer cells, indicating its great potential as a new drug delivery system for cancer therapy. PMID:27151282

  5. [Anti-platelet actions of salicylates: in vivo, ex vivo and in vitro effects of choline salicylate].

    PubMed

    Irino, O; Saitoh, K; Ohkubo, K

    1985-07-01

    Effects of choline salicylate, sodium salicylate, choline chloride and acetylsalicylic acid on platelet aggregation in vivo, ex vivo and in vitro in mice were studied. These drugs all inhibited adenosine diphosphate (ADP)-induced respiratory depression, which is closely related to platelet aggregation in vivo, with choline salicylate showing the strongest inhibitory effect. Choline salicylate had a tendency to reduce the mortality of animals injected intravenously with endotoxin, but the other drugs had no such effect. The inhibitory effects of these drugs on ADP-induced platelet aggregation ex vivo were in the order of choline salicylate greater than acetylsalicylic acid congruent to sodium salicylate greater than choline chloride congruent to no effect, and plasma concentrations of protein-unbound salicylic acid at 1 hr after oral administration of drugs were in the order of choline salicylate greater than acetylsalicylic acid congruent to sodium salicylate. The in vitro effects of these drugs were in the order of choline salicylate congruent to sodium salicylate greater than choline chloride congruent to acetylsalicylic acid congruent to no effect. Therefore, it was considered that salicylic acid played an important role on the in vivo, ex vivo and in vitro effects of choline salicylate and that choline increased plasma concentrations of salicylic acid and consequently enhanced the in vivo and ex vivo effects of salicylic acid. Furthermore, the ex vivo effects of choline salicylate were found when ADP-induced platelet aggregation was measured with platelet-rich plasma prepared from blood collected with heparin as anti-coagulant, but not when blood was collected with citrate.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:4043866

  6. Higher Dietary Choline and Betaine Intakes Are Associated with Better Body Composition in the Adult Population of Newfoundland, Canada

    PubMed Central

    Gao, Xiang; Wang, Yongbo; Randell, Edward; Pedram, Pardis; Yi, Yanqing; Gulliver, Wayne; Sun, Guang

    2016-01-01

    Background Choline is an essential nutrient and betaine is an osmolyte and methyl donor. Both are important to maintain health including adequate lipid metabolism. Supplementation of dietary choline and betaine increase muscle mass and reduce body fat in animals. However, little data is available regarding the role of dietary choline and betaine on body composition in humans. Objective To investigate the association between dietary choline and betaine intakes with body composition in a large population based cross-sectional study. Design A total of 3214 subjects from the CODING (Complex Disease in Newfoundland population: Environment and Genetics) study were assessed. Dietary choline and betaine intakes were computed from the Willett Food Frequency questionnaire. Body composition was measured using dual-energy X-ray absorptiometry following a 12-hour fast. Major confounding factors including age, sex, total calorie intake and physical activity level were controlled in all analyses. Result Significantly inverse correlations were found between dietary choline and betaine intakes, with all obesity measurements: total percent body fat (%BF), percent trunk fat (%TF), percent android fat (%AF), percent gynoid fat (%GF) and anthropometrics: weight, body mass index, waist circumference, waist-to-hip ratio in both women and men (r range from -0.13 to -0.47 for choline and -0.09 to -0.26 for betaine, p<0.001 for all). Dietary choline intake had stronger association than betaine. Moreover, obese subjects had the lowest dietary choline and betaine intakes, with overweight subjects in the middle, and normal weight subjects consumed the highest dietary choline and betaine (p<0.001). Vice versa, when subjects were ranked according to dietary choline and betaine intakes, subjects with the highest intake of both had the lowest %TF, %AF, %GF, %BF and highest %LM among the groups in both sexes. Conclusion Our findings indicate that high dietary choline and betaine intakes are

  7. Prenatal choline availability modulates hippocampal neurogenesis and neurogenic responses to enriching experiences in adult female rats

    PubMed Central

    Glenn, Melissa J.; Gibson, Erin M.; Kirby, Elizabeth D.; Mellott, Tiffany J.; Blusztajn, Jan K.; Williams, Christina L.

    2008-01-01

    Increased dietary intake of choline early in life improves performance of adult rats on memory tasks and prevents their age-related memory decline. Because neurogenesis in the adult hippocampus also declines with age, we investigated whether prenatal choline availability affects hippocampal neurogenesis in adult Sprague–Dawley rats and modifies their neurogenic response to environmental stimulation. On embryonic days (ED) 12−17, pregnant rats ate a choline-supplemented (SUP-5 g/kg), choline sufficient (SFF-1.1 g/kg), or choline-free (DEF) semisynthetic diet. Adult offspring either remained in standard housing or were given 21 daily visits to explore a maze. On the last ten exploration days, all rats received daily injections of 5-bromo-2-deoxyuridine (BrdU, 100 mg/kg). The number of BrdU+ cells was significantly greater in the dentate gyrus in SUP rats compared to SFF or DEF rats. While maze experience increased the number of BrdU+ cells in SFF rats to the level seen in the SUP rats, this enriching experience did not alter cell proliferation in DEF rats. Similar patterns of cell proliferation were obtained with immunohistochemical staining for neuronal marker doublecortin, confirming that diet and exploration affected hippocampal neurogenesis. Moreover, hippocampal levels of the brain-derived neurotrophic factor (BDNF) were increased in SUP rats as compared to SFF and DEF animals. We conclude that prenatal choline intake has enduring effects on adult hippocampal neurogenesis, possibly via up-regulation of BDNF levels, and suggest that these alterations of neurogenesis may contribute to the mechanism of life-long changes in cognitive function governed by the availability of choline during gestation. PMID:17445242

  8. The effect of centrally injected CDP-choline on respiratory system; involvement of phospholipase to thromboxane signaling pathway.

    PubMed

    Topuz, Bora B; Altinbas, Burcin; Yilmaz, Mustafa S; Saha, Sikha; Batten, Trevor F; Savci, Vahide; Yalcin, Murat

    2014-05-01

    CDP-choline is an endogenous metabolite in phosphatidylcholine biosynthesis. Exogenous administration of CDP-choline has been shown to affect brain metabolism and to exhibit cardiovascular, neuroendocrine neuroprotective actions. On the other hand, little is known regarding its respiratory actions and/or central mechanism of its respiratory effect. Therefore the current study was designed to investigate the possible effects of centrally injected CDP-choline on respiratory system and the mediation of the central cholinergic receptors and phospholipase to thromboxane signaling pathway on CDP-choline-induced respiratory effects in anaesthetized rats. Intracerebroventricularly (i.c.v.) administration of CDP-choline induced dose- and time-dependent increased respiratory rates, tidal volume and minute ventilation of male anaesthetized Spraque Dawley rats. İ.c.v. pretreatment with atropine failed to alter the hyperventilation responses to CDP-choline whereas mecamylamine, cholinergic nicotinic receptor antagonist, mepacrine, phospholipase A2 inhibitor, and neomycin phospholipase C inhibitor, blocked completely the hyperventilation induced by CDP-choline. In addition, central pretreatment with furegrelate, thromboxane A2 synthesis inhibitor, also partially blocked CDP-choline-evoked hyperventilation effects. These data show that centrally administered CDP-choline induces hyperventilation which is mediated by activation of central nicotinic receptors and phospholipase to thromboxane signaling pathway. PMID:24560778

  9. Effects of Choline on DNA Methylation and Macronutrient Metabolic Gene Expression in In Vitro Models of Hyperglycemia

    PubMed Central

    Jiang, Xinyin; Greenwald, Esther; Jack-Roberts, Chauntelle

    2016-01-01

    Choline is an essential nutrient that plays an important role in lipid metabolism and DNA methylation. Studies in rodents suggest that choline may adversely affect glycemic control, yet studies in humans are lacking. Using the human hepatic and placental cells, HepG2 and BeWo, respectively, we examined the interaction between choline and glucose treatments. In HepG2 cells, choline supplementation (1 mM) increased global DNA methylation and DNA methyltransferase expression in both low-glucose (5 mM) and high-glucose (35 mM) conditions. Choline supplementation increased the expression of peroxisomal acyl-coenzyme A oxidase 1 (ACOX1), which mediates fatty acid β-oxidation, especially in the high-glucose condition. High-glucose exposure increased the transcription of the gluconeogenic gene phosphoenolpyruvate carboxykinase (PEPCK), while choline supplementation mitigated such increase. Compared to HepG2 cells, the placenta-derived BeWo cells were relatively unresponsive to either high-glucose or -choline treatment. In conclusion, choline and glucose interacted to affect macronutrient metabolic genes, yet there was no indication that choline may worsen glycemic control in these in vitro human cell culture models. PMID:27081315

  10. Hepatotoxicity and endothelial dysfunction induced by high choline diet and the protective effects of phloretin in mice.

    PubMed

    Ren, Daoyuan; Liu, Yafei; Zhao, Yan; Yang, Xingbin

    2016-08-01

    The involvement of choline and its metabolite trimethylamine-N-oxide (TMAO) in endothelial dysfunction and atherosclerosis has been repeatedly confirmed. Phloretin, a dihydrochalcone flavonoid usually present in apples, possesses a variety of biological activities including vascular nutrition. This study was designed to investigate whether phloretin could alleviate or prevent high choline-induced vascular endothelial dysfunction and liver injury in mice. Mice were provided with 3% high choline water and given phloretin orally daily for 10 weeks. The high choline-treated mice showed the significant dyslipidemia and hyperglycemia with the impaired liver and vascular endothelium (p < 0.01). Administration of phloretin at 200 and 400 mg/kg bw significantly reduced the choline-induced elevation of serum TC, TG, LDL-C, AST, ALT, ET-1 and TXA2 (p < 0.01), and markedly antagonized the choline-induced decrease of serum PGI2, HDL-C and NO levels. Furthermore, phloretin elevated hepatic SOD and GSH-Px activities and decreased hepatic MDA levels of the mice exposed to high choline water. Moreover, histopathological test with the H&E and Oil Red O staining of liver sections confirmed the high choline diet-caused liver steatosis and the hepatoprotective effect of phloretin. These findings suggest that high choline causes oxidative damage, and phloretin alleviate vascular endothelial dysfunction and liver injury. PMID:27316781

  11. Volumetric Modulated Arc Therapy Planning for Primary Prostate Cancer With Selective Intraprostatic Boost Determined by {sup 18}F-Choline PET/CT

    SciTech Connect

    Kuang, Yu; Wu, Lili; Hirata, Emily; Miyazaki, Kyle; Sato, Miles

    2015-04-01

    Purpose: This study evaluated expected tumor control and normal tissue toxicity for prostate volumetric modulated arc therapy (VMAT) with and without radiation boosts to an intraprostatically dominant lesion (IDL), defined by {sup 18}F-choline positron emission tomography/computed tomography (PET/CT). Methods and Materials: Thirty patients with localized prostate cancer underwent {sup 18}F-choline PET/CT before treatment. Two VMAT plans, plan{sub 79} {sub Gy} and plan{sub 100-105} {sub Gy}, were compared for each patient. The whole-prostate planning target volume (PTV{sub prostate}) prescription was 79 Gy in both plans, but plan{sub 100-105} {sub Gy} added simultaneous boost doses of 100 Gy and 105 Gy to the IDL, defined by 60% and 70% of maximum prostatic uptake on {sup 18}F-choline PET (IDL{sub suv60%} and IDL{sub suv70%}, respectively, with IDL{sub suv70%} nested inside IDL{sub suv60%} to potentially enhance tumor specificity of the maximum point dose). Plan evaluations included histopathological correspondence, isodose distributions, dose-volume histograms, tumor control probability (TCP), and normal tissue complication probability (NTCP). Results: Planning objectives and dose constraints proved feasible in 30 of 30 cases. Prostate sextant histopathology was available for 28 cases, confirming that IDL{sub suv60%} adequately covered all tumor-bearing prostate sextants in 27 cases and provided partial coverage in 1 case. Plan{sub 100-105} {sub Gy} had significantly higher TCP than plan{sub 79} {sub Gy} across all prostate regions for α/β ratios ranging from 1.5 Gy to 10 Gy (P<.001 for each case). There were no significant differences in bladder and femoral head NTCP between plans and slightly lower rectal NTCP (endpoint: grade ≥ 2 late toxicity or rectal bleeding) was found for plan{sub 100-105} {sub Gy}. Conclusions: VMAT can potentially increase the likelihood of tumor control in primary prostate cancer while observing normal tissue tolerances through

  12. Norepinephrine uptake by rat jejunum: Modulation by angiotensin II

    SciTech Connect

    Suvannapura, A.; Levens, N.R. )

    1988-02-01

    Angiotensin II (ANG II) is believed to stimulate sodium and water absorption from the small intestine by enhancing sympathetic nerve transmission. This study is designed to determine whether ANG II can enhance sympathetic neurotransmission within the small intestine by inhibition norepinephrine (NE) uptake. Intracellular NE accumulation by rat jejunum was concentration dependent and resolved into high- and low-affinity components. The high-affinity component (uptake 1) exhibited a Michaelis constant (K{sub m}) of 1.72 {mu}M and a maximum velocity (V{sub max}) of 1.19 nmol {center dot} g{sup {minus}1} {center dot} 10 min{sup {minus}1}. The low-affinity component (uptake 2) exhibited a K{sub m} of 111.1 {mu}M and a V{sub max} of 37.1 nmol {center dot} g{sup {minus}1} {center dot} 10 min{sup {minus}1}. Cocaine, an inhibitor of neuronal uptake, inhibited the intracellular accumulation of label by 80%. Treatment of animals with 6-hydroxydopamine, which depletes norepinephrine from sympathetic terminals, also attenuated NE uptake by 60%. Thus accumulation within sympathetic nerves constitutes the major form of ({sup 3}H)NE uptake into rat jejunum. ANG II inhibited intracellular ({sup 3}H)NE uptake in a concentration-dependent manner. At a dose of 1 mM, ANG II inhibited intracellular ({sup 3}H)NE accumulation by 60%. Cocaine failed to potentiate the inhibition of ({sup 3}H)NE uptake produced by ANG II. Thus ANG II appears to prevent ({sup 3}H)NE accumulation within rat jejunum by inhibiting neuronal uptake.

  13. Brain protection against ischemic stroke using choline as a new molecular bypass treatment

    PubMed Central

    Jin, Xin; Wang, Ru-huan; Wang, Hui; Long, Chao-liang; Wang, Hai

    2015-01-01

    Aim: To determine whether administration of choline could attenuate brain injury in a rat model of ischemic stroke and the underlying mechanisms. Methods: A rat model of ischemic stroke was established through permanent middle cerebral artery occlusion (pMCAO). After the surgery, the rats were treated with choline or choline plus the specific α7 nAChR antagonist methyllycaconitine (MLA), or with the control drug nimodipine for 10 days. The neurological deficits, brain-infarct volume, pial vessel density and the number of microvessels in the cortex were assessed. Rat brain microvascular endothelial cells (rBMECs) cultured under hypoxic conditions were used in in vitro experiments. Results: Oral administration of choline (100 or 200 mg·kg−1·d−1) or nimodipine (20 mg·kg−1·d−1) significantly improved neurological deficits, and reduced infarct volume and nerve cell loss in the ischemic cerebral cortices in pMCAO rats. Furthermore, oral administration of choline, but not nimodipine, promoted the pial arteriogenesis and cerebral-cortical capillary angiogenesis in the ischemic regions. Moreover, oral administration of choline significantly augmented pMCAO-induced increases in the expression levels of α7 nAChR, HIF-1α and VEGF in the ischemic cerebral cortices as well as in the serum levels of VEGF. Choline-induced protective effects were prevented by co-treatment with MLA (1 mg·kg−1·d−1, ip). Treatment of rBMECs cultured under hypoxic conditions in vitro with choline (1, 10 and 100 μmol/L) dose-dependently promoted the endothelial-cell proliferation, migration and tube formation, as well as VEGF secretion, which were prevented by co-treatment with MLA (1 μmol/L) or by transfection with HIF-1α siRNA. Conclusion: Choline effectively attenuates brain ischemic injury in pMCAO rats, possibly by facilitating pial arteriogenesis and cerebral-cortical capillary angiogenesis via upregulating α7 nAChR levels and inducing the expression of HIF-1α and VEGF

  14. Physical and chemical immobilization of choline oxidase onto different porous solid supports: Adsorption studies.

    PubMed

    Passos, Marieta L C; Ribeiro, David S M; Santos, João L M; Saraiva, M Lúcia M F S

    2016-08-01

    This work carries out for the first time the comparison between the physical and chemical immobilization of choline oxidase onto aminated silica-based porous supports. The influence on the immobilization efficiency of concentration, pH, temperature and contact time between the support and choline oxidase, was evaluated. The immobilization efficiency was estimated taking into consideration the choline oxidase activity, which was assessed by using cadmium telluride (CdTe) quantum dots (QDs), obtained by hydrothermal synthesis, as photoluminescent probes. Hydrogen peroxide produced by enzyme activity was capable of quenching CdTe QDs photoluminescence. The magnitude of the PL quenching process was directly related with the enzyme activity. By comparing the chemical process with the physical adsorption, it was observed that the latter provided the highest choline oxidase immobilization. The equilibrium data were analyzed using Langmuir and Freundlich isotherms and kinetic data were fitted to the pseudo-first-order and pseudo-second-order models. Thermodynamic parameters, such as Gibbs free energy and entropy were also calculated. These results will certainly contribute to the development of new sensing schemes for choline, taking into account the growing demand for its quantification in biological samples. PMID:27241295

  15. Suppressed expression of choline monooxygenase in sugar beet on the accumulation of glycine betaine.

    PubMed

    Yamada, Nana; Takahashi, Hiroyuki; Kitou, Kunihide; Sahashi, Kosuke; Tamagake, Hideto; Tanaka, Yoshito; Takabe, Teruhiro

    2015-11-01

    Glycine betaine (GB) is an important osmoprotectant and synthesized by two-step oxidation of choline. Choline monooxygenase (CMO) catalyzes the first step of the pathway and is believed to be a rate limiting step for GB synthesis. Recent studies have shown the importance of choline-precursor supply for GB synthesis. In order to investigate the role of CMO for GB accumulation in sugar beet (Beta vulgaris), transgenic plants carrying the antisense BvCMO gene were developed. The antisense BvCMO plants showed the decreased activity of GB synthesis from choline compared to wild-type (WT) plants which is well related to the suppressed level of BvCMO protein. However, GB contents were similar between transgenic and WT plants with the exception of young leaves and storage roots. Transgenic plants showed enhanced susceptibility to salt stress than WT plants. These results suggest the importance of choline-precursor-supply for GB accumulation, and young leaves and storage root are sensitive sites for GB accumulation. PMID:26302482

  16. Structural and kinetic studies on the Ser101Ala variant of choline oxidase: Catalysis by compromise

    SciTech Connect

    Finnegan, S.; Orville, A.; Yuan, H.; Wang, Y.-F.; Weber, I. T.; Gadda, G.

    2010-09-15

    The oxidation of choline catalyzed by choline oxidase includes two reductive half-reactions where FAD is reduced by the alcohol substrate and by an aldehyde intermediate transiently formed in the reaction. Each reductive half-reaction is followed by an oxidative half-reaction where the reduced flavin is oxidized by oxygen. Here, we have used mutagenesis to prepare the Ser101Ala mutant of choline oxidase and have investigated the impact of this mutation on the structural and kinetic properties of the enzyme. The crystallographic structure of the Ser101Ala enzyme indicates that the only differences between the mutant and wild-type enzymes are the lack of a hydroxyl group on residue 101 and a more planar configuration of the flavin in the mutant enzyme. Kinetics established that replacement of Ser101 with alanine yields a mutant enzyme with increased efficiencies in the oxidative half-reactions and decreased efficiencies in the reductive half-reactions. This is accompanied by a significant decrease in the overall rate of turnover with choline. Thus, this mutation has revealed the importance of a specific residue for the optimization of the overall turnover of choline oxidase, which requires fine-tuning of four consecutive half-reactions for the conversion of an alcohol to a carboxylic acid.

  17. Plasmodium falciparum Choline Kinase Inhibition Leads to a Major Decrease in Phosphatidylethanolamine Causing Parasite Death.

    PubMed

    Serrán-Aguilera, Lucía; Denton, Helen; Rubio-Ruiz, Belén; López-Gutiérrez, Borja; Entrena, Antonio; Izquierdo, Luis; Smith, Terry K; Conejo-García, Ana; Hurtado-Guerrero, Ramon

    2016-01-01

    Malaria is a life-threatening disease caused by different species of the protozoan parasite Plasmodium, with P. falciparum being the deadliest. Increasing parasitic resistance to existing antimalarials makes the necessity of novel avenues to treat this disease an urgent priority. The enzymes responsible for the synthesis of phosphatidylcholine and phosphatidylethanolamine are attractive drug targets to treat malaria as their selective inhibition leads to an arrest of the parasite's growth and cures malaria in a mouse model. We present here a detailed study that reveals a mode of action for two P. falciparum choline kinase inhibitors both in vitro and in vivo. The compounds present distinct binding modes to the choline/ethanolamine-binding site of P. falciparum choline kinase, reflecting different types of inhibition. Strikingly, these compounds primarily inhibit the ethanolamine kinase activity of the P. falciparum choline kinase, leading to a severe decrease in the phosphatidylethanolamine levels within P. falciparum, which explains the resulting growth phenotype and the parasites death. These studies provide an understanding of the mode of action, and act as a springboard for continued antimalarial development efforts selectively targeting P. falciparum choline kinase. PMID:27616047

  18. Amperometric Choline Biosensor Fabricated through Electrostatic Assembly of Bienzyme/Polyelectrolyte Hybrid Layers on Carbon Nanotubes

    SciTech Connect

    Wang, Jun; Liu, Guodong; Lin, Yuehe

    2006-03-01

    We report a flow injection amperometric choline biosensors based on the electrostatic assembly of an enzyme of choline oxidase (ChO) and a bi-enzyme of ChO and horseradish peroxidase (HRP) onto multi-wall carbon nanotubes (MWCNT) modified glassy carbon (GC) electrodes. These choline biosensors were fabricated by immobilization of enzymes on the negatively charged MWCNT surface through alternatively assembling a cationic polydiallydiimethylammonium chloride (PDDA) layer and an enzyme layer. Using this layer-by-layer assembling approach, bioactive nanocomposite film of a PDDA/ChO/PDDA/HRP/PDDA/CNT (ChO/HRP/CNT) and a PDDA/ChO/PDDA/ CNT (ChO/ CNT) were fabricated on GC surface, respectively. Owning to the electrocatalytic effect of carbon nanotubes, the measurement of faradic responses resulting from enzymatic reactions has been realized at low potential with acceptable sensitivity. It is found the ChO/HRP/CNT biosensor is more sensitive than the ChO/CNT one. Experimental parameters affecting the sensitivity of biosensors, e.g. applied potential, flow rate, etc. were optimized and potential interference was examined. The response time for this choline biosensor is fast (less than a few seconds). The linear range of detection for the choline biosensor is from 5 x 10-5 to 5 x 10-3 M and the detection limit is determined to be about 1.0 x 10-5 M.

  19. Choline Ameliorates Disease Phenotypes in Human iPSC Models of Rett Syndrome.

    PubMed

    Chin, Eunice W M; Marcy, Guillaume; Yoon, Su-In; Ma, Dongliang; Rosales, Francisco J; Augustine, George J; Goh, Eyleen L K

    2016-09-01

    Rett syndrome (RTT) is a postnatal neurodevelopmental disorder that primarily affects girls. Mutations in the methyl-CpG-binding protein 2 (MECP2) gene account for approximately 95 % of all RTT cases. To model RTT in vitro, we generated induced pluripotent stem cells (iPSCs) from fibroblasts of two RTT patients with different mutations (MECP2 (R306C) and MECP2 (1155Δ32)) in their MECP2 gene. We found that these iPSCs were capable of differentiating into functional neurons. Compared to control neurons, the RTT iPSC-derived cells had reduced soma size and a decreased amount of synaptic input, evident both as fewer Synapsin 1-positive puncta and a lower frequency of spontaneous excitatory postsynaptic currents. Supplementation of the culture media with choline rescued all of these defects. Choline supplementation may act through changes in the expression of choline acetyltransferase, an important enzyme in cholinergic signaling, and also through alterations in the lipid metabolite profiles of the RTT neurons. Our study elucidates the possible mechanistic pathways for the effect of choline on human RTT cell models, thereby illustrating the potential for using choline as a nutraceutical to treat RTT. PMID:27379379

  20. Estimation of usual intake and food sources of choline and betaine in New Zealand reproductive age women.

    PubMed

    Mygind, Vanessa L; Evans, Sophie E; Peddie, Meredith C; Miller, Jody C; Houghton, Lisa A

    2013-01-01

    Recently, choline has been associated with neurodevelopment, cognitive function and neural tube defect incidence. However, data on usual intakes are limited, and estimates of dietary intakes of choline and its metabolite betaine, are not available for New Zealanders. The objective of the present study was to determine usual intake and food sources of choline and betaine in a group of New Zealand reproductive age women. Dietary intake data were collected from a sample of 125 women, aged 18-40 years, by means of a 3-day weighed food record, and usual choline and betaine intake distributions were determined. The mean (SD) daily intakes of choline and betaine were 316 (66) mg and 178 (66) mg, respectively. The total choline intake relative to energy intake and body weight was 0.18 mg/kcal and 5.1 mg/kg, respectively. Only 16% of participants met or exceeded the Adequate Intake (AI) for adult women of 425 mg of choline. The top five major food contributors of choline were eggs, red meat, milk, bread and chicken; and of betaine were bread, breakfast cereal, pasta, grains and root vegetables (carrots, parsnips, beetroot, swedes). Our findings contribute towards the recent emergence of published reports on the range of dietary choline and betaine intakes consumed by free-living populations. In our sample of New Zealand women, few participants were meeting or exceeding the AI level. Given recent epidemiological evidence suggesting health benefits of increased choline and betaine intakes, recommendations should be made to encourage the consumption of choline and betaine-rich foods. PMID:23635379

  1. Overview of affinity tags for protein purification.

    PubMed

    Kimple, Michelle E; Sondek, John

    2004-09-01

    Addition of an affinity tag is a useful method for differentiating recombinant proteins expressed in bacterial and eukaryotic expression systems from the background of total cellular proteins, and for detecting protein-protein interactions. This overview describes the historical basis for the development of affinity tags, affinity tags that are commonly used today, how to choose an appropriate affinity tag for a particular purpose, and several recently developed affinity tag technologies that may prove useful in the near future. PMID:18429272

  2. Overview of affinity tags for protein purification.

    PubMed

    Kimple, Michelle E; Brill, Allison L; Pasker, Renee L

    2013-01-01

    Addition of an affinity tag is a useful method for differentiating recombinant proteins expressed in bacterial and eukaryotic expression systems from the background of total cellular proteins, as well as for detecting protein-protein interactions. This overview describes the historical basis for the development of affinity tags, affinity tags that are commonly used today, how to choose an appropriate affinity tag for a particular purpose, and several recently developed affinity tag technologies that may prove useful in the near future. PMID:24510596

  3. Functional analysis of the ferric uptake requlator gene, fur, in Xanthomonas vesicatoria

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Iron is essential for the growth and survival of many organisms. Intracellular iron homeostasis must be maintained for cell survival and protection against iron toxicity. The ferric uptake regulator protein (Fur) regulates the high-affinity ferric uptake system in many bacteria. To investigate the f...

  4. Hepatotoxicity associated with choline magnesium trisalicylate: case report and review of salicylate-induced hepatotoxicity.

    PubMed

    Cersosimo, R J; Matthews, S J

    1987-01-01

    A case of a 21-year-old woman who had developed mild hepatotoxicity while receiving choline magnesium trisalicylate therapy is described. She presented with fever and mild hepatic enzyme elevations before salicylate therapy was instituted. Liver function tests (LFT) returned to normal within five days of hospitalization but she continued to develop daily fevers. Blood, urine, and throat cultures were negative. An acute viral illness or reactivation of systemic lupus erythematosus were the suspected diagnoses. Choline magnesium trisalicylate was then administered in an effort to control her fever, and was successful. After three days of salicylate therapy her LFT values began to rise. They continued to rise for five more days before salicylate hepatotoxicity was suspected. Choline magnesium trisalicylate was discontinued after eight days and the patient's LFT quickly returned to normal. The source of fever was never identified, although infection with cytomegalovirus was considered the most likely cause. Salicylate-induced hepatotoxicity is reviewed. PMID:3301251

  5. Evolutionary Design of Choline-Inducible and -Repressible T7-Based Induction Systems.

    PubMed

    Ike, Kohei; Arasawa, Yusuke; Koizumi, Satoshi; Mihashi, Satoshi; Kawai-Noma, Shigeko; Saito, Kyoichi; Umeno, Daisuke

    2015-12-18

    By assembly and evolutionary engineering of T7-phage-based transcriptional switches made from endogenous components of the bet operon on the Escherichia coli chromosome, genetic switches inducible by choline, a safe and inexpensive compound, were constructed. The functional plasticity of the BetI repressor was revealed by rapid and high-frequency identification of functional variants with various properties, including those with high stringency, high maximum expression level, and reversed phenotypes, from a pool of BetI mutants. The plasmid expression of BetI mutants resulted in the choline-inducible (Bet-ON) or choline-repressible (Bet-OFF) switching of genes under the pT7/betO sequence at unprecedentedly high levels, while keeping the minimal leaky expression in uninduced conditions. PMID:26289535

  6. Effect of chlorphentermine on incorporation of (/sup 14/C)choline in the rat lung phospholipids

    SciTech Connect

    Gonmori, K.; Morita, T.; Mehendale, H.M.

    1986-03-01

    The effect of chlorphentermine (CP) treatment (50 mg/kg/day, per os (po)) on the incorporation of (/sup 14/C)choline into rat lung phospholipid was studied. Total phospholipid content was increased 2.0-fold and 1.7-fold after seven and /sup 14/ days, respectively, compared with the pair-fed rats. The incorporation of (14C)choline into phosphatidylcholine (PC) was significantly inhibited by either seven or 14 days of CP treatment. Nevertheless, the PC content was significantly increased by day 7 and stayed elevated at day 14 of CP treatment. Choline and phosphorylcholine contents were significantly decreased by the CP treatment. These results suggest that the higher accumulation of PC is due to inhibition of enzymes involved in the hydrolysis of phospholipids rather than to a stimulation of the phospholipid synthesis.

  7. Interaction and dynamics of ionic liquids based on choline and amino acid anions

    SciTech Connect

    Campetella, M.; Bodo, E. Caminiti, R. Martino, A.; Gontrani, L.; D’Apuzzo, F.; Lupi, S.

    2015-06-21

    The combination of amino acid anions with the choline cation gives origin to a new and potentially important class of organic ionic liquids that might represent a viable and bio-compatible alternative with respect to the traditional ones. We present here a detailed study of the bulk phase of the prototype system composed of the simplest amino acid (alanine) anion and the choline cation, based on ab initio and classical molecular dynamics. Theoretical findings have been validated by comparing with accurate experimental X-ray diffraction data and infrared spectra. We find that hydrogen bonding (HB) features in these systems are crucial in establishing their local geometric structure. We have also found that these HBs once formed are persistent and that the proton resides exclusively on the choline cation. In addition, we show that a classical force field description for this particular ionic liquid can be accurately performed by using a slightly modified version of the generalized AMBER force field.

  8. Interaction and dynamics of ionic liquids based on choline and amino acid anions

    NASA Astrophysics Data System (ADS)

    Campetella, M.; Bodo, E.; Caminiti, R.; Martino, A.; D'Apuzzo, F.; Lupi, S.; Gontrani, L.

    2015-06-01

    The combination of amino acid anions with the choline cation gives origin to a new and potentially important class of organic ionic liquids that might represent a viable and bio-compatible alternative with respect to the traditional ones. We present here a detailed study of the bulk phase of the prototype system composed of the simplest amino acid (alanine) anion and the choline cation, based on ab initio and classical molecular dynamics. Theoretical findings have been validated by comparing with accurate experimental X-ray diffraction data and infrared spectra. We find that hydrogen bonding (HB) features in these systems are crucial in establishing their local geometric structure. We have also found that these HBs once formed are persistent and that the proton resides exclusively on the choline cation. In addition, we show that a classical force field description for this particular ionic liquid can be accurately performed by using a slightly modified version of the generalized AMBER force field.

  9. Affine Contractions on the Plane

    ERIC Educational Resources Information Center

    Celik, D.; Ozdemir, Y.; Ureyen, M.

    2007-01-01

    Contractions play a considerable role in the theory of fractals. However, it is not easy to find contractions which are not similitudes. In this study, it is shown by counter examples that an affine transformation of the plane carrying a given triangle onto another triangle may not be a contraction even if it contracts edges, heights or medians.…

  10. Quantifying Affinity among Chinese Dialects.

    ERIC Educational Resources Information Center

    Cheng, Chin-Chuan

    A study of the relationships between Chinese dialects based on a quantitative measure of dialect affinity is summarized. First, tone values in all the dialect localities available in the early 1970s were used to calculate the dialectal differences in terms of tone height with respect to the "yin and yang" split. In the late 1970s, calculations of…

  11. Influence of 11C-choline PET/CT on radiotherapy planning in prostate cancer

    PubMed Central

    López, Escarlata; Lazo, Antonio; Gutiérrez, Antonio; Arregui, Gregorio; Núñez, Isabel; Sacchetti, Antonio

    2014-01-01

    Aim To evaluate the influence of 11C-choline PET/CT on radiotherapy planning in prostate cancer patients. Background Precise information on the extension of prostate cancer is crucial for the choice of an appropriate therapeutic strategy. 11C-choline positron emission tomography (11C-choline PET/CT) has two roles in radiation oncology (RT): (1) patient selection for treatment and (2) target volume selection and delineation. In conjunction with high-accuracy techniques, it might offer an opportunity of dose escalation and better tumour control while sparing healthy tissues. Materials and methods We carried out a retrospective study in order to analyse RT planning modification based on 11C-choline PET/CT in 16 prostate cancer patients. Patients were treated with hypofractionated step-and-shoot Intensity Modulated Radiotherapy (IMRT), or Volumetric Modulated Arc Therapy (VMAT), and a daily cone-beam CT for Image Guided Radiation Therapy (IGRT). All patients underwent a 11C-choline-PET/CT scan prior to radiotherapy. Results In 37.5% of cases, a re-delineation and new dose prescription occurred. Data show good preliminary clinical results in terms of biochemical control and toxicity. No gastrointestinal (GI)/genitourinary (GU) grade III toxicities were observed after a median follow-up of 9.5 months. Conclusions In our experience, concerning the treatment of prostate cancer (PCa), 11C-choline PET/CT may be helpful in radiotherapy planning, either for dose escalation or exclusion of selected sites. PMID:25859399

  12. Dietary folate, but not choline, modifies neural tube defect risk in Shmt1 knockout mice12345

    PubMed Central

    Beaudin, Anna E; Abarinov, Elena V; Malysheva, Olga; Perry, Cheryll A; Caudill, Marie; Stover, Patrick J

    2012-01-01

    Background: Low dietary choline intake has been proposed to increase the risk of neural tube defects (NTDs) in human populations. Mice with reduced Shmt1 expression exhibit a higher frequency of NTDs when placed on a folate- and choline-deficient diet and may represent a model of human NTDs. The individual contribution of dietary folate and choline deficiency to NTD incidence in this mouse model is not known. Objective: To dissociate the effects of dietary folate and choline deficiency on Shmt1-related NTD sensitivity, we determined NTD incidence in embryos from Shmt1-null dams fed diets deficient in either folate or choline. Design: Shmt1+/+ and Shmt1−/− dams were maintained on a standard AIN93G diet (Dyets), an AIN93G diet lacking folate (FD), or an AIN93G diet lacking choline (CD). Virgin Shmt1+/+ and Shmt1−/− dams were crossed with Shmt1+/− males, and embryos were examined for the presence of NTDs at embryonic day (E) 11.5 or E12.5. Results: Exencephaly was observed only in Shmt1−/− embryos isolated from dams maintained on the FD diet (P = 0.004). Approximately 33% of Shmt1−/−embryos (n = 18) isolated from dams maintained on the FD diet exhibited exencephaly. NTDs were not observed in any embryos isolated from dams maintained on the CD (n = 100) or control (n = 152) diets or in any Shmt1+/+ (n = 78) or Shmt1+/− embryos (n = 182). Conclusion: Maternal folate deficiency alone is sufficient to induce NTDs in response to embryonic Shmt1 disruption. PMID:22134951

  13. How polar are choline chloride-based deep eutectic solvents?

    PubMed

    Pandey, Ashish; Rai, Rewa; Pal, Mahi; Pandey, Siddharth

    2014-01-28

    Developing and characterizing green solvents with low toxicity and cost is one of the most important issues in chemistry. Deep Eutectic Solvents (DESs), in this regard, have shown tremendous promise. Compared to popular organic solvents, DESs possess negligible VOCs and are non-flammable. Compared to ionic liquids, which share many characteristics but are ionic compounds and not ionic mixtures, DESs are cheaper to make, much less toxic and mostly biodegradable. An estimate of the polarity associated with DESs is essential if they are to be used as green alternatives to common organic solvents in industries and academia. As no one physical parameter can satisfactorily represent solute-solvent interactions within a medium, polarity of DESs is assessed through solvatochromic optical spectroscopic responses of several UV-vis absorbance and molecular fluorescence probes. Information on the local microenvironment (i.e., the cybotactic region) that surrounds several solvatochromic probes [betaine dye, pyrene, pyrene-1-carboxaldehyde, 1-anilino-8-naphthalene sulfonate (ANS), p-toluidinyl-6-naphthalene sulfonate (TNS), 6-propionyl-2-(dimethylaminonaphthalene) (PRODAN), coumarin-153, and Nile Red] for four common and popular DESs formed from choline chloride combined with 1,2-ethanediol, glycerol, urea, and malonic acid, respectively, in 1 : 2 molar ratios termed ethaline, glyceline, reline, and maline is obtained and used to assess the effective polarity afforded by each of these DESs. The four DESs as indicated by these probe responses are found to be fairly dipolar in nature. Absorbance probe betaine dye and fluorescence probes ANS, TNS, PRODAN, coumarin-153, and Nile Red, whose solvatochromic responses are based on photoinduced charge-transfer, imply ethaline and glyceline, DESs formed using alcohol-based H-bond donors, to be relatively more dipolar in nature as compared to reline and maline. The pyrene polarity scale, which is based on polarity-induced changes in

  14. Na sup + uptake into colonic enterocyte membrane vesicles

    SciTech Connect

    Bridges, R.J.; Garty, H.; Benos, D.J.; Rummel, W. Weizmann Institute of Science, Rehovot Univ. of Alabama, Birmingham )

    1988-04-01

    Na{sup +} uptake was studied in colonic enterocyte membrane vesicles prepared from normal and dexamethasone-treated rats. Vesicles from rats treated with dexamethasone demonstrated a fivefold greater {sup 22}Na{sup +} uptake compared with vesicles from normal rats. Most of the tracer uptake in membranes derived from treated rats occurred through a conductive, amiloride-blockable pathway located in vesicles with low native K{sup +} permeability and high Cl{sup {minus}} permeability. Kinetic analysis of the amiloride inhibition curve revealed the presence of two amiloride-blockable pathways, one with a high affinity accounting for 85% of the uptake, and one with a low affinity accounting for only 12% of the uptake. Only the low-affinity pathway was detected with vesicles from normal rats. The high sensitivity to amiloride, the dependence on dexamethasone pretreatment, and the relative permeabilities to K{sup +} and Cl{sup {minus}} indicate that most of the {sup 22}Na{sup +} uptake in membranes derived from treated rats is through a Na{sup +}-specific channel located in apical membrane vesicles. Preincubation of the isolated cells from dexamethasone-treated rats at 37{degree}C in Ca{sup 2+}-free solutions before homogenization and membrane vesicle purification caused a 5- to 10-fold increase in amiloride-blockable {sup 22}Na{sup +} uptake compared with vesicles derived from cells maintained at 0{degree}C. The addition of Ca{sup 2+}, but not of Mg{sup 2+}, to the incubation solution markedly reduced this temperature-dependent enhancement in {sup 22}Na{sup +} uptake. These results suggest that Na{sup +} transport in colonic enterocytes from dexamethasone-treated rats is regulated by a Ca{sup 2+}-dependent, temperature-sensitive process which causes a sustained change in the apical membrane.

  15. Choline chloride based ionic liquid analogues as tool for the fabrication of agar films with improved mechanical properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the present paper, we test the suitability of Choline-Cl/urea (DES-U) and Choline-Cl/glycerol (DES-G) eutectic mixtures at 1:2 molar ratios for the production of agar biodegradable films. A three-step process is proposed: pre-solubilization of polymer in DES followed by compression-molding and s...

  16. Choline, Its Potential Role in Nonalcoholic Fatty Liver Disease, and the Case for Human and Bacterial Genes.

    PubMed

    Sherriff, Jill L; O'Sullivan, Therese A; Properzi, Catherine; Oddo, Josephine-Lee; Adams, Leon A

    2016-01-01

    Our understanding of the impact of poor hepatic choline/phosphatidylcholine availability in promoting the steatosis characteristic of human nonalcoholic fatty liver disease (NAFLD) has recently advanced and possibly relates to phosphatidylcholine/phosphatidylethanolamine concentrations in various, membranes as well as cholesterol dysregulation. A role for choline/phosphatidylcholine availability in the progression of NAFLD to liver injury and serious hepatic consequences in some individuals requires further elucidation. There are many reasons for poor choline/phosphatidylcholine availability in the liver, including low intake, estrogen status, and genetic polymorphisms affecting, in particular, the pathway for hepatic de novo phosphatidylcholine synthesis. In addition to free choline, phosphatidylcholine has been identified as a substrate for trimethylamine production by certain intestinal bacteria, thereby reducing host choline bioavailability and providing an additional link to the increased risk of cardiovascular disease faced by those with NAFLD. Thus human choline requirements are highly individualized and biomarkers of choline status derived from metabolomics studies are required to predict those at risk of NAFLD induced by choline deficiency and to provide a basis for human intervention trials. PMID:26773011

  17. Effects of CDP-choline on neurologic deficits and cerebral glucose metabolism in a rat model of cerebral ischemia

    SciTech Connect

    Kakihana, M.; Fukuda, N.; Suno, M.; Nagaoka, A.

    1988-02-01

    The effects of cytidine 5'-diphosphocholine (CDP-choline) on neurologic deficits and cerebral glucose metabolism were studied in a rat model of transient cerebral ischemia. Cerebral ischemia was induced by occluding both common carotid arteries for 20 or 30 minutes 24 hours after the vertebral arteries were permanently occluded by electrocautery. CDP-choline was administered intraperitoneally twice daily for 4 days after reestablishing carotid blood flow. CDP-choline at two dosages (50 and 250 mg/kg) shortened the time required for recovery of spontaneous motor activity in a dose-related manner; recovery time was measured early after reperfusion. Neurologic signs were observed for 10 days. High-dose CDP-choline improved neurologic signs in the rats within 20-30 minutes of ischemia. When cerebral glucose metabolism was assessed on Day 4, increases in the levels of glucose and pyruvate were accompanied by decreases in the synthesis of labeled acetylcholine from uniformly labeled (/sup 14/C)glucose measured in the cerebral cortex of rats with 30 minutes of ischemia. High-dose CDP-choline also attenuated changes in these variables. CDP-(1,2-/sup 14/C)choline injected intravenously 10 minutes after reperfusion was used for membrane lipid biosynthesis. These results indicate that CDP-choline has beneficial effects on brain dysfunction induced by cerebral ischemia, which may be due in part to the restorative effects of CDP-choline on disturbed cerebral glucose metabolism, probably by stimulating phospholipid biosynthesis.

  18. 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...

  19. Are dietary choline and betaine intakes determinants of total homocysteine concentration?1234

    PubMed Central

    Lee, Jung Eun; Jacques, Paul F; Dougherty, Lauren; Selhub, Jacob; Giovannucci, Edward; Zeisel, Steven H

    2010-01-01

    Background: Elevated homocysteine concentrations are associated with an increased risk of cardiovascular disease and a decline in cognitive function. Intakes of choline and betaine, as methyl donors, may affect homocysteine concentrations. Objective: The objective was to examine whether choline and betaine intakes, assessed from food-frequency questionnaires, are associated with total plasma homocysteine concentrations under both fasting and post–methionine-load conditions in both pre– and post–folic acid fortification periods in the United States. Design: We assessed the association between choline and betaine intakes and fasting and post–methionine-load homocysteine concentrations using the US Department of Agriculture revised food-composition tables and evaluated whether the associations varied by folic acid fortification periods in 1325 male and 1407 female participants in the sixth examination (1995–1998) of the Framingham Offspring Study. Results: A higher choline-plus-betaine intake was associated with lower concentrations of post–methionine-load homocysteine; the multivariate geometric means were 24.1 μmol/L (95% CI: 23.4, 24.9 μmol/L) in the top quintile of intake and 25.0 μmol/L (95% CI: 24.2, 25.7 μmol/L) in the bottom quintile (P for trend = 0.01). We found an inverse association between choline-plus-betaine intake and fasting homocysteine concentrations; the multivariate geometric mean fasting homocysteine concentrations were 9.6 μmol/L (95% CI: 9.3, 9.9 μmol/L) in the top quintile and 10.1 μmol/L (95% CI: 9.8, 10.4 μmol/L) in the bottom quintile (P for trend < 0.001). When we stratified by plasma folate and vitamin B-12 concentrations, the inverse association was limited to participants with low plasma folate or vitamin B-12 concentrations. In the postfortification period, the inverse association between choline-plus-betaine intake and either fasting or post–methionine-load homocysteine was no longer present. Conclusions: Choline

  20. Plasma free choline, betaine and cognitive performance: the Hordaland Health Study.

    PubMed

    Nurk, Eha; Refsum, Helga; Bjelland, Ingvar; Drevon, Christian A; Tell, Grethe S; Ueland, Per M; Vollset, Stein E; Engedal, Knut; Nygaard, Harald A; Smith, David A

    2013-02-14

    Choline and betaine are nutrients involved in one-carbon metabolism. Choline is essential for neurodevelopment and brain function. We studied the associations between cognitive function and plasma concentrations of free choline and betaine. In a cross-sectional study, 2195 subjects (55 % women), aged 70-74 years, underwent extensive cognitive testing including the Kendrick Object Learning Test (KOLT), Trail Making Test (part A, TMT-A), modified versions of the Digit Symbol Test (m-DST), Block Design (m-BD), Mini-Mental State Examination (m-MMSE) and Controlled Oral Word Association Test (COWAT). Compared with low concentrations, high choline (>8·4 μmol/l) was associated with better test scores in the TMT-A (56·0 v. 61·5, P=0·004), m-DST (10·5 v. 9·8, P=0·005) and m-MMSE (11·5 v. 11·4, P=0·01). A generalised additive regression model showed a positive dose-response relationship between the m-MMSE and choline (P=0·012 from a corresponding linear regression model). Betaine was associated with the KOLT, TMT-A and COWAT, but after adjustments for potential confounders, the associations lost significance. Risk ratios (RR) for poor test performance roughly tripled when low choline was combined with either low plasma vitamin B₁₂ (≤257 pmol/l) concentrations (RR(KOLT)=2·6, 95 % CI 1·1, 6·1; RR(m-MMSE)=2·7, 95 % CI 1·1, 6·6; RR(COWAT)=3·1, 95 % CI 1·4, 7·2) or high methylmalonic acid (MMA) (≥3·95 μmol/l) concentrations (RR(m-BD)=2·8, 95 % CI 1·3, 6·1). Low betaine (≤31·1 μmol/l) combined with high MMA was associated with elevated RR on KOLT (RR(KOLT)=2·5, 95 % CI 1·0, 6·2). Low plasma free choline concentrations are associated with poor cognitive performance. There were significant interactions between low choline or betaine and low vitamin B₁₂ or high MMA on cognitive performance. PMID:22717142

  1. Transformation of Synechococcus with a gene for choline oxidase enhances tolerance to salt stress.

    PubMed

    Deshnium, P; Los, D A; Hayashi, H; Mustardy, L; Murata, N

    1995-12-01

    Choline oxidase, isolated from the soil bacterium Arthrobacter globiformis, converts choline to glycinebetaine (N-trimethylglycine) without a requirement for any cofactors. The gene for this enzyme, designated codA, was cloned and introduced into the cyanobacterium Synechococcus sp. PCC 7942. The codA gene was expressed under the control of a strong constitutive promoter, and the transformed cells accumulated glycinebetaine at intracellular levels of 60-80 mM. Consequently the cells acquired tolerance to salt stress, as evaluated in terms of growth, accumulation of chlorophyll and photosynthetic activity. PMID:8555454

  2. Myasthenic syndrome: effect of choline, plasmapheresis and tests for circulating factor.

    PubMed Central

    Kranz, H; Caddy, D J; Williams, A M; Gay, W

    1980-01-01

    In a patient with myasthenic syndrome neuro-muscular transmission was characterised by depression and facilitation. The relative extent of these two processes varied between muscles, and in the one muscle with time. Guanidine HCl treatment corrected the electrophysiological defect. Oral choline increased muscle action potential amplitude in response to single shocks. Intravenous choline produced features indicating cholinergic autonomic stimulation. Pimozide and plasmapheresis had no effect. Animal in-vivo and in-vitro studies performed to detect a circulating factor which interferes with neuro-muscular transmission were negative. PMID:6110709

  3. Effects of Choline on Meat Quality and Intramuscular Fat in Intrauterine Growth Retardation Pigs.

    PubMed

    Li, Bo; Li, Wei; Ahmad, Hussain; Zhang, Lili; Wang, Chao; Wang, Tian

    2015-01-01

    The aim of this study was to investigate the effects of choline supplementation on intramuscular fat (IMF) and lipid oxidation in IUGR pigs. Twelve normal body weight (NBW) and twelve intrauterine growth retardation (IUGR) newborn piglets were collected and distributed into 4 treatments (Normal: N, Normal+Choline: N+C, IUGR: I, and IUGR+Choline: I+C) with 6 piglets in each treatment. At 23 d of age, NBW and IUGR pigs were fed basal or choline supplemented diets. The results showed that the IUGR pigs had significantly lower (P<0.05) BW as compared with the NBW pigs at 23 d, 73 d, and 120 d of age, however, there was a slight decreased (P>0.05) in BW of IUGR pigs than the NBW pigs at 200 d. Compared with the NBW pigs, pH of meat longissimus dorsi muscle was significantly lower (P<0.05), and the meat color was improved in IUGR pigs. The malondialdehyde (MDA) levels were significantly decreased (P<0.05), while triglyceride (TG) and IMF contents were significantly higher (P<0.05) in the IUGR pigs than the NBW pigs. IUGR up-regulated the mRNA gene expression of fatty acid synthetase (FAS) and acetyl-CoA carboxylase (ACC). Dietary choline significantly increased (P<0.05) the BW at 120d of age, however, significantly decreased (P<0.05) the TG and IMF contents in both IUGR and NBW pigs. FAS and sterol regulatory element-binding proteins 1 (SREBP1) mRNA gene expressions were increased (P<0.05) while the muscle-carnitine palmityl transferase (M-CPT) and peroxisome proliferators-activated receptorγ (PPARγ) mRNA (P<0.05) gene expressions were decreased in the muscles of the IUGR pigs by choline supplementation. Furthermore, choline supplementation significantly increased (P<0.05) the MDA content as well as the O2•¯ scavenging activity in meat of IUGR pigs. The results suggested that IUGR pigs showed a permanent stunting effect on the growth performance, increased fat deposition and oxidative stress in muscles. However, dietary supplementation of choline improved the fat

  4. Morphological effects of cytidin-diphosphate-choline on rats with lesions of the substantia nigra: study using horse radish peroxidase method.

    PubMed

    Stanzani, S

    1981-09-15

    Morphological effects of Cytidin-diphosphate-Choline (CDP-choline) (Ni-cholin) on rat brain with Substantia nigra lesions were studied by using the horse radish peroxidase method (HRP). Three groups of animals were studied. Post-lesion axonal and cellular regeneration was detected only in the group of rats treated with CDP-choline q.d. i.m. for 15 days. PMID:7306424

  5. Theoretical proton affinity and fluoride affinity of nerve agent VX.

    PubMed

    Bera, Narayan C; Maeda, Satoshi; Morokuma, Keiji; Viggiano, Al A

    2010-12-23

    Proton affinity and fluoride affinity of nerve agent VX at all of its possible sites were calculated at the RI-MP2/cc-pVTZ//B3LYP/6-31G* and RI-MP2/aug-cc-pVTZ//B3LYP/6-31+G* levels, respectively. The protonation leads to various unique structures, with H(+) attached to oxygen, nitrogen, and sulfur atoms; among which the nitrogen site possesses the highest proton affinity of -ΔE ∼ 251 kcal/mol, suggesting that this is likely to be the major product. In addition some H(2), CH(4) dissociation as well as destruction channels have been found, among which the CH(4) + [Et-O-P(═O)(Me)-S-(CH(2))(2)-N(+)(iPr)═CHMe] product and the destruction product forming Et-O-P(═O)(Me)-SMe + CH(2)═N(+)(iPr)(2) are only 9 kcal/mol less stable than the most stable N-protonated product. For fluoridization, the S-P destruction channel to give Et-O-P(═O)(Me)(F) + [S-(CH(2))(2)-N-(iPr)(2)](-) is energetically the most favorable, with a fluoride affinity of -ΔE ∼ 44 kcal. Various F(-) ion-molecule complexes are also found, with the one having F(-) interacting with two hydrogen atoms in different alkyl groups to be only 9 kcal/mol higher than the above destruction product. These results suggest VX behaves quite differently from surrogate systems. PMID:21117653

  6. Homogeneous liquid-liquid extraction of neodymium(III) by choline hexafluoroacetylacetonate in the ionic liquid choline bis(trifluoromethylsulfonyl)imide.

    PubMed

    Onghena, Bieke; Jacobs, Jeroen; Van Meervelt, Luc; Binnemans, Koen

    2014-08-14

    The ionic liquid choline bis(trifluoromethylsulfonyl)imide, [Chol][Tf2N], was used for the extraction of neodymium(III), in combination with choline hexafluoroacetylacetonate, [Chol][hfac], as the extractant. The binary mixture of [Chol][Tf2N] and water shows temperature-dependent phase behavior, with an upper critical solution temperature of 72 °C. A novel extraction technique, homogeneous liquid-liquid extraction (HLLE), was applied to this solvent system. HLLE is based on the use of thermomorphic solvent mixtures and has the advantage of forming a homogeneous phase during mixing. Extraction is not kinetically hindered by an interface and the extraction equilibrium is reached faster than in the case of heterogeneous mixing in conventional solvent extraction. Several extraction parameters were studied for the extraction of neodymium(III) with [Chol][hfac]: temperature, pH, extractant concentration and loading of the ionic liquid phase. A speciation study was performed to determine the stoichiometry of the extracted neodymium(III) complex and a plausible extraction mechanism is proposed. Neodymium is extracted as a tetrakis hexafluoroacetylacetonate complex with one choline cation as counter ion. The crystal structure of the extracted complex showed the presence of a coordination bond between the choline counter ion and the neodymium(III) center, resulting in a coordination number of nine. The stripping of the loaded neodymium and the influence of acid and extractant concentrations on the phase behavior of the [Chol][Tf2N]-H2O system were investigated. PMID:24938933

  7. Central injection of CDP-choline suppresses serum ghrelin levels while increasing serum leptin levels in rats.

    PubMed

    Kiyici, Sinem; Basaran, Nesrin Filiz; Cavun, Sinan; Savci, Vahide

    2015-10-01

    In this study we aimed to test central administration of CDP-choline on serum ghrelin, leptin, glucose and corticosterone levels in rats. Intracerebroventricular (i.c.v.) 0.5, 1.0 and 2.0 µmol CDP-choline and saline were administered to male Wistar-Albino rats. For the measurement of serum leptin and ghrelin levels, blood samples were obtained baseline and at 5, 15, 30, 60 and 120 min following i.c.v. CDP-choline injection. Equimolar doses of i.c.v. choline (1.0 µmol) and cytidine (1.0 µmol) were administered and measurements were repeated throughout the second round of the experiment. Atropine (10 µg) and mecamylamine (50 µg) were injected intracerebroventricularly prior to CDP-choline and measurements repeated in the third round of the experiment. After 1 µmol CDP-choline injection, serum ghrelin levels were suppressed significantly at 60 min (P=0.025), whereas serum leptin levels were increased at 60 and 120 min (P=0.012 and P=0.017 respectively). CDP-choline injections also induced a dose- and time-dependent increase in serum glucose and corticosterone levels. The effect of choline on serum leptin and ghrelin levels was similar with CDP-choline while no effect was seen with cytidine. Suppression of serum ghrelin levels was eliminated through mecamylamine pretreatment while a rise in leptin was prevented by both atropine and mecamylamine pretreatments. In conclusion; centrally injected CDP-choline suppressed serum ghrelin levels while increasing serum leptin levels. The observed effects following receptor antagonist treatment suggest that nicotinic receptors play a role in suppression of serum ghrelin levels,whereas nicotinic and muscarinic receptors both play a part in the increase of serum leptin levels. PMID:26162700

  8. High affinity dopamine D2 receptor radioligands. 1. Regional rat brain distribution of iodinated benzamides.

    PubMed

    Kessler, R M; Ansari, M S; de Paulis, T; Schmidt, D E; Clanton, J A; Smith, H E; Manning, R G; Gillespie, D; Ebert, M H

    1991-08-01

    Five 125I-labeled substituted benzamides, which are close structural analogues of (S)-sulpiride, eticlopride, and isoremoxipride, were evaluated for their selective in vivo uptake into dopamine D2 receptor rich tissue of the rat brain. "Iodopride" (KD 0.88 nM), an iodine substituted benzamide structurally related to sulpiride, displayed a maximal striatum: cerebellar uptake ratio of 7.6. Demonstration of saturation of the receptor with [125I]iodopride in striatum required uptake in frontal cortex to be used, rather than cerebellar uptake, to define nonspecific binding. Two other ligands structurally related to eticlopride, "iclopride" (KD 0.23 nM) and "itopride" (KD 0.16 nM), displayed maximal striatal: cerebellar uptake ratios of 9.8 and 3.3, respectively. The most potent ligands, "epidepride" (KD 0.057 nM) and "ioxipride" (KD 0.070 nM) showed striatal:cerebellar uptake ratios of 234 and 65, respectively. The observed uptake ratios correlated poorly with the affinity constants for the dopamine D2 receptor alone, but were highly correlated (r = 0.92) with the product of the receptor dissociation constant (KD) and the apparent lipophilicity (kw), as determined by reverse-phase HPLC at pH 7.5. Total striatal uptake also appeared dependent on lipophilicity, with maximal uptake occurring for ligands having log kw 2.4-2.8. PMID:1831229

  9. High affinity dopamine D2 receptor radioligands. 1. Regional rat brain distribution of iodinated benzamides

    SciTech Connect

    Kessler, R.M.; Ansari, M.S.; de Paulis, T.; Schmidt, D.E.; Clanton, J.A.; Smith, H.E.; Manning, R.G.; Gillespie, D.; Ebert, M.H. )

    1991-08-01

    Five 125I-labeled substituted benzamides, which are close structural analogues of (S)-sulpiride, eticlopride, and isoremoxipride, were evaluated for their selective in vivo uptake into dopamine D2 receptor rich tissue of the rat brain. Iodopride (KD 0.88 nM), an iodine substituted benzamide structurally related to sulpiride, displayed a maximal striatum: cerebellar uptake ratio of 7.6. Demonstration of saturation of the receptor with (125I)iodopride in striatum required uptake in frontal cortex to be used, rather than cerebellar uptake, to define nonspecific binding. Two other ligands structurally related to eticlopride, iclopride (KD 0.23 nM) and itopride (KD 0.16 nM), displayed maximal striatal: cerebellar uptake ratios of 9.8 and 3.3, respectively. The most potent ligands, epidepride (KD 0.057 nM) and ioxipride (KD 0.070 nM) showed striatal:cerebellar uptake ratios of 234 and 65, respectively. The observed uptake ratios correlated poorly with the affinity constants for the dopamine D2 receptor alone, but were highly correlated (r = 0.92) with the product of the receptor dissociation constant (KD) and the apparent lipophilicity (kw), as determined by reverse-phase HPLC at pH 7.5. Total striatal uptake also appeared dependent on lipophilicity, with maximal uptake occurring for ligands having log kw 2.4-2.8.

  10. Comparative uptake kinetics and transport of cadmium and phosphate in Phleum pratense-Glomus deserticolum associations

    SciTech Connect

    Arnold, P.T.; Kapustka, L.A. )

    1993-01-01

    Mycorrhizal plants (timothy grass, Phleum pretense with Glomus deserticolum) were compared to nonmycorrhizal timothy grass to determine the effect of the mycorrhizal condition on the uptake and transport of cadmium. Companion experiments were conducted to ascertain phosphate uptake kinetics of mycorrhizal and nonmycorrhizal plants. Divalent cation competition experiments also were employed in this study. Comparisons of the high-affinity uptake mechanisms between mycorrhizal and nonmycorrhizal plants identified higher levels of phosphate uptake were due to an increase in the number of uptake sites rather than to differences in affinity. The respective values for K[sub m] for high-affinity phosphate uptake were 2.5 [plus minus] 1.3 [mu]MP (mycorrhizal) and 3.4 [plus minus] 1.3 [mu]MP (nonmycorrhizal), but these values were not statistically different at the [alpha] = 0.05 level. High-affinity Cd[sup 2+] uptake differed significantly between mycorrhizal (4.5 [plus minus] 2.8 [mu]M) and nonmycorrhizal (2.8 [plus minus] 1.1 [mu]M) plants. Presence of Ca[sup 2+] at 1.0mM concentration conferred considerable competitive protection in both the mycorrhizal and the nonmycorrhizal conditions. The effect of Ca[sup 2+] was an approximate fourfold increase in the respective K[sub m] values.

  11. Lectin affinity chromatography of glycolipids

    SciTech Connect

    Torres, B.V.; Smith, D.F.

    1987-05-01

    Since glycolipids (GLs) are either insoluble or form mixed micelles in water, lectin affinity chromatography in aqueous systems has not been applied to their separation. They have overcome this problem by using tetrahydrofuran (THF) in the mobile phase during chromatography. Affinity columns prepared with the GalNAc-specific Helix pomatia agglutinin (HPA) and equilibrated in THF specifically bind the (/sup 3/H)oligosaccharide derived from Forssman GL indicating that the immobilized HPA retained its carbohydrate-binding specificity in this solvent. Intact Forssman GL was bound by the HPA-column equilibrated in THF and was specifically eluted with 0.1 mg/ml GalNAc in THF. Purification of the Forssman GL was achieved when a crude lipid extract of sheep erythrocyte membranes was applied to the HPA-column in THF. Non-specifically bound GLs were eluted from the column using a step gradient of aqueous buffer in THF, while the addition of GalNAc was required to elute the specifically bound GLs. Using this procedure the A-active GLs were purified from a crude lipid extract of type A human erythrocytes in a single chromatographic step. The use of solvents that maintain carbohydrate-binding specificity and lipid solubility will permit the application of affinity chromatography on immobilized carbohydrate-binding proteins to intact GLs.

  12. Dietary intakes of choline: What We Eat In America, NHANES 2007-2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this report is to present data on the choline intake of the U.S. population and the food categories that contribute to intake. The dietary data was from twenty-four hour recall provided by all 9,118 individuals who participated in What We Eat In America, NHANES 2007–2008. The analys...

  13. Comparable Stability of Hoogsteen and Watson–Crick Base Pairs in Ionic Liquid Choline Dihydrogen Phosphate

    PubMed Central

    Tateishi-Karimata, Hisae; Nakano, Miki; Sugimoto, Naoki

    2014-01-01

    The instability of Hoogsteen base pairs relative to Watson–Crick base pairs has limited biological applications of triplex-forming oligonucleotides. Hydrated ionic liquids (ILs) provide favourable environments for a wide range of chemical reactions and are known to impact the stabilities of Watson–Crick base pairs. We found that DNA triplex formation was significantly stabilized in hydrated choline dihydrogen phosphate as compared with an aqueous buffer at neutral pH. Interestingly, the stability of Hoogsteen base pairs was found to be comparable with that of Watson–Crick base pairs in the hydrated IL. Molecular dynamics simulations of a DNA triplex in the presence of choline ions revealed that the DNA triplex was stabilized because of the binding of choline ion around the third strand in the grooves. Our finding will facilitate the development of new DNA materials. Our data also indicate that triplex formation may be stabilized inside cells where choline ions and their derivatives are abundant in vivo. PMID:24399194

  14. Choline-releasing glycerophosphodiesterase EDI3 links the tumor metabolome to signaling network activities.

    PubMed

    Marchan, Rosemarie; Lesjak, Michaela S; Stewart, Joanna D; Winter, Roland; Seeliger, Janine; Hengstler, Jan G

    2012-12-15

    Recently, EDI3 was identified as a key factor for choline metabolism that controls tumor cell migration and is associated with metastasis in endometrial carcinomas. EDI3 cleaves glycerophosphocholine (GPC) to form choline and glycerol-3-phosphate (G3P). Choline is then further metabolized to phosphatidylcholine (PtdC), the major lipid in membranes and a key player in membrane-mediated cell signaling. The second product, G3P, is a precursor molecule for several lipids with central roles in signaling, for example lysophosphatidic acid (LPA), phosphatidic acid (PA) and diacylglycerol (DAG). LPA activates intracellular signaling pathways by binding to specific LPA receptors, including membrane-bound G protein-coupled receptors and the intracellular nuclear receptor, PPARγ. Conversely, PA and DAG mediate signaling by acting as lipid anchors that bind and activate several signaling proteins. For example, binding of GTPases and PKC to PA and DAG, respectively, increases the activation of signaling networks, mediating processes such as migration, adhesion, proliferation or anti-apoptosis-all relevant for tumor development. We present a concept by which EDI3 either directly generates signaling molecules or provides "membrane anchors" for downstream signaling factors. As a result, EDI3 links choline metabolism to signaling activities resulting in a more malignant phenotype. PMID:23114620

  15. Studies on the riboflavin, pantothenic acid, nicotinic acid and choline requirements of young Embden geese

    USGS Publications Warehouse

    Serafin, J.A.

    1981-01-01

    Four experiments were conducted to examine the riboflavin, pantothenic acid, nicotinic acid, and choline requirements of young Embden geese fed purified diets. Goslings fed diets deficient in either riboflavin, pantothenic acid, nicotinic acid, or choline grew poorly. Feeding a pantothenic acid-deficient diet resulted in 100% mortality. Goslings fed diets containing 530 mg/kg of choline or less developed perosis. Under the conditions of these experiments it was found that: 1) goslings require no more than 3.84 mg/kg of riboflavin and 31.2 mg/kg of nicotinic acid in the diet for rapid growth and normal development, 2) the pantothenic acid requirement of goslings is no more than 12.6 mg/kg of diet, and 3) a dietary choline level of 1530 mg/kg is adequate for both the prevention of perosis and rapid growth of goslings. The levels of vitamins found to support normal growth and development of goslings appear to be similar to requirements of other species that have been examined.

  16. Dietary CDP-Choline Supplementation Prevents Memory Impairment Caused by Impoverished Environmental Conditions in Rats

    ERIC Educational Resources Information Center

    Teather, Lisa A.; Wurtman, Richard J.

    2005-01-01

    The authors previously showed that dietary cytidine (5')-diphosphocholine (CDP-choline) supplementation could protect against the development of memory deficits in aging rats. In the present study, younger rats exposed to impoverished environmental conditions and manifesting hippocampal-dependent memory impairments similar to those observed in the…

  17. Studies on the riboflavin, pantothenic acid, nicotinic acid, and choline requirements of young Embden geese.

    PubMed

    Serafin, J A

    1981-08-01

    Four experiments were conducted to examine the riboflavin, pantothenic acid, nicotinic acid, and choline requirements of young Embden geese fed purified diets. Goslings fed diets deficient in either riboflavin, pantothenic acid, nicotinic acid, or choline grew poorly. Feeding a pantothenic acid-deficient diet resulted in 100% mortality. Goslings fed diets containing 530 mg/kg of choline or less developed perosis. Under the conditions of these experiments it was found that: 1) goslings require no more than 3.84 mg/kg of riboflavin and 31.2 mg/kg of nicotinic acid in the diet for rapid growth and normal development, 2) the pantothenic acid requirement of goslings is no more than 12.6 mg/kg of diet, and 3) a dietary choline level of 1530 mg/kg is adequate for both the prevention of perosis and rapid growth of goslings. The levels of vitamins found to support normal growth and development of goslings appear to be similar to requirements of other species that have been examined. PMID:7322986

  18. Regulation of betaine synthesis by precursor supply and choline monooxygenase expression in Amaranthus tricolor.

    PubMed

    Bhuiyan, Nazmul H; Hamada, Akira; Yamada, Nana; Rai, Vandna; Hibino, Takashi; Takabe, Teruhiro

    2007-01-01

    In plants, betaine is synthesized upon abiotic stress via choline oxidation, in which choline monooxygenase (CMO) is a key enzyme. Although it had been thought that betaine synthesis is well regulated to protect abiotic stress, it is shown here that an exogenous supply of precursors such as choline, serine, and glycine in the betaine-accumulating plant Amaranthus tricolor further enhances the accumulation of betaine under salt stress, but not under normal conditions. Addition of isonicotinic acid hydrazide, an inhibitor of glycine decarboxylase, inhibited the salinity-induced accumulation of betaine. Salt-induced accumulation of A. tricolor CMO (AmCMO) and betaine was much slower in roots than in leaves, and a transient accumulation of proline was observed in the roots. Antisense expression of AmCMO mRNA suppressed the salt-induced accumulation of AmCMO and betaine, but increased the level of choline approximately 2- 3-fold. This indicates that betaine synthesis is highly regulated by AmCMO expression. The genomic DNA, including the upstream region (1.6 kbp), of AmCMO was isolated. Deletion analysis of the AmCMO promoter region revealed that the 410 bp fragment upstream of the translation start codon contains the sequence responsive to salt stress. These data reveal that the promoter sequence of CMO, in addition to precursor supply, is important for the accumulation of betaine in the betaine-accumulating plant A. tricolor. PMID:18182425

  19. Evaluation of toxicity and biodegradability of choline chloride based deep eutectic solvents.

    PubMed

    Radošević, Kristina; Bubalo, Marina Cvjetko; Srček, Višnje Gaurina; Grgas, Dijana; Dragičević, Tibela Landeka; Redovniković, Ivana Radojčić

    2015-02-01

    Deep eutectic solvents (DESs) have been dramatically expanding in popularity as a new generation of environmentally friendly solvents with possible applications in various industrial fields, but their ecological footprint has not yet been thoroughly investigated. In the present study, three choline chloride-based DESs with glucose, glycerol and oxalic acid as hydrogen bond donors were evaluated for in vitro toxicity using fish and human cell line, phytotoxicity using wheat and biodegradability using wastewater microorganisms through closed bottle test. Obtained in vitro toxicity data on cell lines indicate that choline chloride: glucose and choline chloride:glycerol possess low cytotoxicity (EC50>10 mM for both cell lines) while choline chloride:oxalic acid possess moderate cytotoxicity (EC50 value 1.64 mM and 4.19 mM for fish and human cell line, respectively). Results on phytotoxicity imply that tested DESs are non-toxic with seed germination EC50 values higher than 5000 mg L(-1). All tested DESs were classified as'readily biodegradable' based on their high levels of mineralization (68-96%). These findings indicate that DESs have a green profile and a good prospect for a wider use in the field of green technologies. PMID:25463852

  20. Human Serial Learning: Enhancement with Arecholine and Choline and Impairment with Scopolamine

    ERIC Educational Resources Information Center

    Sitaram, N.; Weingartner, Herbert

    1978-01-01

    The effects of particular drugs in human memory abilities was examined. The degree of memory enhancement produced by arecholine and choline and the impairment after scopolamaine were inversely proportional to the subject's performance in placebo; that is, "poor" performers were more vulnerable to the drugs than were "good" performers. (Author/CP)

  1. Methanogenesis from choline by a coculture of Desulfovibrio sp. and Methanosarcina barkeri

    SciTech Connect

    Fiebig, K.; Gottschalk, G.

    1983-01-01

    A sulfate-reducing vibrio was isolated from a methanogenic enrichment with choline as the sole added organic substrate. This oganism was identified as a member of the genus Desulfovibrio and was designated Desulfovibrio strain G1. In a defined medium devoid of sulfate, a pure culture of Desulfovibrio strain G1 fermented choline to trimethylamine, acetate, and ethanol. In the presence of sulfate, more acetate and less ethanol were formed from choline than in the absence of sulfate. When grown in a medium containing sulfate, a coculture of Desulfovibrio strain G1 and Methanosarcina barkeri strain Fusaro degraded chloline almost completely to methane, ammonia, and hydrogen sulfide and presumably to carbon dioxide. Methanogenesis occurred in two distinct phases separated by a lag of about 6 days. During the first phase of methanogenesis choline was completely converted to trimethylamine, acetate, hydrogen sulfide, and traces of ethanol by the desulfovibrio.M. barkeri fermented trimethylamine to methane, ammonia, and presumably carbon dioxide via dimethyl- and methylamine as intermediates. Simultaneously, about 60% of the acetate expected was metabolized. In the second phase of methanogenesis, the residual acetate was almost completely catabolized.

  2. PROLONGED SURVIVAL OF FEMALE AKR MICE FED DIETS SUPPLEMENTED WITH METHIONINE AND CHOLINE

    EPA Science Inventory

    Female mice of the AKR/J(AK) strain were fed a control diet (Purina chow) or a lipotrope-supplemented diet (Purina chow plus 2% D.L-methionine and 1% choline chloride) beginning at one week after weaning. ice of this inbred strain spontaneously develop thymic lymphoma, with close...

  3. Biocompatibility of choline salts as crosslinking agents for collagen based biomaterials.

    PubMed

    Vijayaraghavan, R; Thompson, B C; MacFarlane, D R; Kumar, Ramadhar; Surianarayanan, M; Aishwarya, S; Sehgal, P K

    2010-01-14

    A series of novel choline based salts, some of which can be described as ionic liquids, are prepared and evaluated for their biocompatibility; when combined with collagenous biomaterials they exhibit good cell viability and adhesion properties as required for biomedical implant applications. PMID:20024356

  4. Studies on the riboflavin, niacin, pantothenic acid and choline requirements of young bobwhite quail

    USGS Publications Warehouse

    Serafin, J.A.

    1974-01-01

    Four experiments were conducted to examine the riboflavin, niacin, pantothenic acid and choline requirements of young Bobwhite quail. Quail fed purified diets deficient in either riboflavin, niacin, pantothenic acid or choline grew poorly and high mortality occurred by 5 weeks of age. Under the conditions of these experiments, it was found that: (1) young quail require approximately 3.8 mg. riboflavin/kg. diet for satisfactory growth and survival; (2) no more than 31 mg. niacin/kg. diet are required for normal growth and survival of young quail; (3) the requirement for pantothenic acid is higher than has previously been reported, quail in these studies requiring 12.6 mg. pantothenic acid/kg. feed for growth and survival; and (4) the requirement for choline for reducing mortality is approximately 1000 mg./kg., while the amount necessary for normal growth of young quail is no greater than 1500 mg./kg. when the diet contains ample amounts of methionine. Quail fed a niacin-deficient diet developed stiff, shortened feathers and an erythema about the head; those receiving a riboflavin-deficient ration developed enlarged hocks and bowed legs, as did quail fed diets low or devoid of choline. Aside from slow growth, poor feathering was the only other indication that a deficient diet was being fed when quail were placed on a basal ration without pantothenic acid for five weeks.

  5. Relationship Between Choline and Apparent Diffusion Coefficient in Patients With Gliomas

    PubMed Central

    Khayal, Inas S.; Crawford, Forrest W.; Saraswathy, Suja; Lamborn, Kathleen R.; Chang, Susan M.; Cha, Soonmee; McKnight, Tracy R.; Nelson, Sarah J.

    2011-01-01

    Purpose To examine the relationship between apparent diffusion coefficients (ADC) from diffusion weighted imaging (DWI) and choline levels from proton magnetic resonance spectroscopic imaging (MRSI) in newly diagnosed Grade II and IV gliomas within distinct anatomic regions. Materials and Methods A total of 37 patients with Grade II and 28 patients with Grade IV glioma were scanned on a 1.5T system with 3D MRSI and DWI. Region level analysis included Spearman rank correlation between median normalized ADC and choline for each patient per grade within each distinct abnormal anatomical region. Voxel level analysis calculated a Spearman rank correlation per region, per patient. Results Grade II lesions showed no evidence of a correlation between normalized ADC and choline using either the region or voxel level analysis. Region level analysis of Grade IV lesions did not appear to correlate in the contrast enhancement or necrotic core, but did suggest a significant negative correlation in the more heterogeneous nonenhancing and combined regions. Conclusion There appears to be differences in the relationship between ADC and choline levels in Grade II and Grade IV gliomas. Correlation within these regions in Grade IV lesions was strongest when all regions were included, suggesting heterogeneity may be driving the relationship. PMID:18383265

  6. Comparable stability of Hoogsteen and Watson-Crick base pairs in ionic liquid choline dihydrogen phosphate.

    PubMed

    Tateishi-Karimata, Hisae; Nakano, Miki; Sugimoto, Naoki

    2014-01-01

    The instability of Hoogsteen base pairs relative to Watson-Crick base pairs has limited biological applications of triplex-forming oligonucleotides. Hydrated ionic liquids (ILs) provide favourable environments for a wide range of chemical reactions and are known to impact the stabilities of Watson-Crick base pairs. We found that DNA triplex formation was significantly stabilized in hydrated choline dihydrogen phosphate as compared with an aqueous buffer at neutral pH. Interestingly, the stability of Hoogsteen base pairs was found to be comparable with that of Watson-Crick base pairs in the hydrated IL. Molecular dynamics simulations of a DNA triplex in the presence of choline ions revealed that the DNA triplex was stabilized because of the binding of choline ion around the third strand in the grooves. Our finding will facilitate the development of new DNA materials. Our data also indicate that triplex formation may be stabilized inside cells where choline ions and their derivatives are abundant in vivo. PMID:24399194

  7. Maternal Choline Supplementation: A Potential Prenatal Treatment for Down Syndrome and Alzheimer's Disease.

    PubMed

    Strupp, Barbara J; Powers, Brian E; Velazquez, Ramon; Ash, Jessica A; Kelley, Christy M; Alldred, Melissa J; Strawderman, Myla; Caudill, Marie A; Mufson, Elliott J; Ginsberg, Stephen D

    2016-01-01

    Although Down syndrome (DS) can be diagnosed prenatally, currently there are no effective treatments to lessen the intellectual disability (ID) which is a hallmark of this disorder. Furthermore, starting as early as the third decade of life, DS individuals exhibit the neuropathological hallmarks of Alzheimer's disease (AD) with subsequent dementia, adding substantial emotional and financial burden to their families and society at large. A potential therapeutic strategy emerging from the study of trisomic mouse models of DS is to supplement the maternal diet with additional choline during pregnancy and lactation. Studies demonstrate that maternal choline supplementation (MCS) markedly improves spatial cognition and attentional function, as well as normalizes adult hippocampal neurogenesis and offers protection to basal forebrain cholinergic neurons (BFCNs) in the Ts65Dn mouse model of DS. These effects on neurogenesis and BFCNs correlate significantly with spatial cognition, suggesting functional relationships. In this review, we highlight some of these provocative findings, which suggest that supplementing the maternal diet with additional choline may serve as an effective and safe prenatal strategy for improving cognitive, affective, and neural functioning in DS. In light of growing evidence that all pregnancies would benefit from increased maternal choline intake, this type of recommendation could be given to all pregnant women, thereby providing a very early intervention for individuals with DS, and include babies born to mothers unaware that they are carrying a fetus with DS. PMID:26391046

  8. Choline and Fructooligosaccharide: Non-alcoholic Fatty Liver Disease, Cardiac Fat Deposition, and Oxidative Stress Markers

    PubMed Central

    Borges Haubert, Nadia Juliana Beraldo Goulart; Marchini, Julio Sergio; Carvalho Cunha, Selma Freire; Suen, Vivian Marques Miguel; Padovan, Gilberto Joao; Jordao, Alceu Afonso; Marchini Alves, Claudia Maria Meirelles; Marchini, Julio Flavio Meirelles; Vannucchi, Helio

    2015-01-01

    This study investigates the treatment of non-alcoholic fatty liver disease (NAFLD) in rats with choline and fructooligosaccharide (FOS). The healthy control group received standard diet. The other three groups consisted of animals with NAFLD. Group Estr received standard diet; group Echo received standard diet plus choline (3 g/100 g diet); and group Efos received standard diet plus FOS (10 g/100 g diet). Food intake, weight, urinary nitrogen, urinary ammonia, total cholesterol, serum triacylglyceride, liver and heart weights, tissue nitrogen, tissue fat, vitamin E, TBARS, and reduced glutathione (GSH) were measured in hepatic and heart tissue. Choline and FOS treatments resulted in total mean fat reduction in liver and heart tissue of 0.2 and 1.7 g, respectively. Both treatments were equally effective in reducing hepatic and cardiac steatosis. There were no differences in the TBARS level among experimental and control groups, indicating that the proposed treatments had no added protection against free radicals. While all experimental groups had increased vitamin E and GSH levels, choline treatment led to a significant increase compared to control. PMID:25987847

  9. The mechanism of zinc uptake by cultured rat liver cells.

    PubMed Central

    Taylor, J A; Simons, T J

    1994-01-01

    1. The initial rate of 65Zn uptake into cultured rat hepatocytes has been measured over a range of Zn2+ concentrations from 3 x 10(-10) M to 5 x 10(-6) M. Histidine and albumin were used to buffer Zn2+ ions at concentrations below 1 x 10(-6) M. 2. The results suggest there are two mechanisms for Zn2+ uptake; a high-affinity, saturable pathway, with a maximum velocity (Vmax) of 20-30 pmol (mg protein)-1 min-1 and a Michaelis-Menten constant (Km) of about 2 x 10(-9) M Zn2+ (with histidine), and a low-affinity, linear pathway, that only makes a significant contribution to Zn2+ uptake at Zn2+ concentrations above 1 x 10(-6) M. 3. Transport via the high-affinity pathway is dependent on the concentration of Zn2+ ions and not on the concentrations of Zn(2+)-ligand complexes, suggesting that Zn2+ is the transported species. 4. The affinity of the saturable pathway for Zn2+ is slightly lower in the presence of albumin, with a Km of about 1.3 x 10(-8) M. The reason for this is uncertain. PMID:8014898

  10. Doubly ionic hydrogen bond interactions within the choline chloride-urea deep eutectic solvent.

    PubMed

    Ashworth, Claire R; Matthews, Richard P; Welton, Tom; Hunt, Patricia A

    2016-07-21

    Deep eutectic solvents (DESs) are exemplars of systems with the ability to form neutral, ionic and doubly ionic H-bonds. Herein, the pairwise interactions of the constituent components of the choline chloride-urea DES are examined. Evidence is found for a tripodal CHCl doubly ionic H-bond motif. Moreover it is found that the covalency of doubly ionic H-bonds can be greater than, or comparable with, neutral and ionic examples. In contrast to many traditional solvents, an "alphabet soup" of many different types of H-bond (OHO[double bond, length as m-dash]C, NHO[double bond, length as m-dash]C, OHCl, NHCl, OHNH, CHCl, CHO[double bond, length as m-dash]C, NHOH and NHNH) can form. These H-bonds exhibit substantial flexibility in terms of number and strength. It is anticipated that H-bonding will have a significant impact on the entropy of the system and thus could play an important role in the formation of the eutectic. The 2 : 1 urea : choline-chloride eutectic point of this DES is often associated with the formation of a [Cl(urea)2](-) complexed anion. However, urea is found to form a H-bonded urea[choline](+) complexed cation that is energetically competitive with [Cl(urea)2](-). The negative charge on [Cl(urea)2](-) is found to remain localised on the chloride, moreover, the urea[choline](+) complexed cation forms the strongest H-bond studied here. Thus, there is potential to consider a urea[choline](+)·urea[Cl](-) interaction. PMID:27328990

  11. Choline intake during pregnancy and child cognition at age 7 years.

    PubMed

    Boeke, Caroline E; Gillman, Matthew W; Hughes, Michael D; Rifas-Shiman, Sheryl L; Villamor, Eduardo; Oken, Emily

    2013-06-15

    Animal models indicate that exposure to choline in utero improves visual memory through cholinergic transmission and/or epigenetic mechanisms. Among 895 mothers in Project Viva (eastern Massachusetts, 1999-2002 to 2008-2011), we estimated the associations between intakes of choline, vitamin B12, betaine, and folate during the first and second trimesters of pregnancy and offspring visual memory (measured by the Wide Range Assessment of Memory and Learning, Second Edition (WRAML2), Design and Picture Memory subtests) and intelligence (measured using the Kaufman Brief Intelligence Test, Second Edition (KBIT-2)) at age 7 years. Mean second-trimester intakes were 328 (standard deviation (SD), 63) mg/day for choline, 10.5 (SD, 5.1) µg/day for vitamin B12, 240 (SD, 104) mg/day for betaine, and 1,268 (SD, 381) µg/day for folate. Mean age 7 test scores were 17.2 (SD, 4.4) points on the WRAML 2 Design and Picture Memory subtests, 114.3 (SD, 13.9) points on the verbal KBIT-2, and 107.8 (SD, 16.5) points on the nonverbal KBIT-2. In a model adjusting for maternal characteristics, the other nutrients, and child's age and sex, the top quartile of second-trimester choline intake was associated with a child WRAML2 score 1.4 points higher (95% confidence interval: 0.5, 2.4) than the bottom quartile (P-trend = 0.003). Results for first-trimester intake were in the same direction but weaker. Intake of the other nutrients was not associated with the cognitive tests administered. Higher gestational choline intake was associated with modestly better child visual memory at age 7 years. PMID:23425631

  12. A microelectrochemical biosensor for real-time in vivo monitoring of brain extracellular choline.

    PubMed

    Baker, Keeley L; Bolger, Fiachra B; Lowry, John P

    2015-06-01

    A first generation Pt-based polymer enzyme composite biosensor developed for real-time neurochemical monitoring was characterised in vivo for sensitive and selective detection of choline. Confirmation that the sensor responds to changes in extracellular choline was achieved using local perfusion of choline which resulted in an increase in current, and the acetylcholinesterase inhibitor neostigmine which produced a decrease. Interference by electroactive species was tested using systemic administration of sodium ascorbate which produced a rapid increase in extracellular levels before gradually returning towards baseline over several hours. There was no overall change in the response of the biosensor during the same period of monitoring. Oxygen interference was examined using pharmacological agents known to change tissue oxygenation. Chloral hydrate produced an immediate increase in O2 before gradually returning to baseline levels over 3 h. The biosensor signal displayed an initial brief decrease before increasing to a maximum after 1 h and returning to baseline within 2 h. L-NAME caused a decrease in O2 before returning to baseline levels after ca. 1.5 h. In contrast, the biosensor current increased over the same time period before slowly returning to baseline levels over several hours. Such differences in time course and direction suggest that changes in tissue O2 levels do not affect the ability of the sensor to monitor choline reliably. Although it was found to rapidly respond to behavioural activation, examination of baseline in vivo data suggests a stable viable signal for at least 14 days after implantation. Using in vitro calibration data the basal extracellular concentration of choline was estimated to be 6.3 μM. PMID:25519498

  13. Metabolism of choline in brain of the aged CBF-1 mouse

    SciTech Connect

    Saito, M.; Kindel, G.; Karczmar, A.G.; Rosenberg, A.

    1986-01-01

    In order to quantify the changes that occur in the cholinergic central nervous system with aging, we have compared acetylcholine (Ach) formation in brain cortex slice preparations from 2-year-old aged CBF-1 mouse brains and compared the findings with those in 2-4-month-old young adult mouse brain slices. Incorporation of exogenous radioactively labelled choline (31 nM (/sup 3/H) choline) into acetyl choline in incubated brain slices was linear with time for 90 min. Percentage of total choline label distributed into Ach remained constant from 5 min after starting the incubation to 90 min. In contrast, distribution of label into intracellular free choline (Ch) and phosphorylcholine (Pch) changed continuously over this period suggesting that the Ch pool for Ach synthesis in brain cortex is different from that for Pch synthesis. Incorporation of radioactivity into Ach was not influenced by administration of 10 microM eserine, showing that the increment of radioactivity in Ach reflects rate of Ach formation, independently from degradation by acetylcholine esterases. Under our experimental conditions, slices from cortices of aged 24-month-old mouse brain showed a significantly greater (27%) incorporation of radioactivity into intracellular Ach than those from young, 2-4-month-old, brain cortices. Inhibitors of Ach release, 1 mM ATP or GABA, had no effect. Since concentration of radioactive precursor in the incubation medium was very low (31 nM), the Ch pool for Ach synthesis in slices was labelled without measurably changing the size of the endogenous pool. These data suggest a compensatory acceleration of Ach synthesis or else a smaller precursor pool specific for Ach synthesis into which labelled Ch migrated in aged brain.

  14. Choline Intake During Pregnancy and Child Cognition at Age 7 Years

    PubMed Central

    Boeke, Caroline E.; Gillman, Matthew W.; Hughes, Michael D.; Rifas-Shiman, Sheryl L.; Villamor, Eduardo; Oken, Emily

    2013-01-01

    Animal models indicate that exposure to choline in utero improves visual memory through cholinergic transmission and/or epigenetic mechanisms. Among 895 mothers in Project Viva (eastern Massachusetts, 1999–2002 to 2008–2011), we estimated the associations between intakes of choline, vitamin B12, betaine, and folate during the first and second trimesters of pregnancy and offspring visual memory (measured by the Wide Range Assessment of Memory and Learning, Second Edition (WRAML2), Design and Picture Memory subtests) and intelligence (measured using the Kaufman Brief Intelligence Test, Second Edition (KBIT-2)) at age 7 years. Mean second-trimester intakes were 328 (standard deviation (SD), 63) mg/day for choline, 10.5 (SD, 5.1) µg/day for vitamin B12, 240 (SD, 104) mg/day for betaine, and 1,268 (SD, 381) µg/day for folate. Mean age 7 test scores were 17.2 (SD, 4.4) points on the WRAML 2 Design and Picture Memory subtests, 114.3 (SD, 13.9) points on the verbal KBIT-2, and 107.8 (SD, 16.5) points on the nonverbal KBIT-2. In a model adjusting for maternal characteristics, the other nutrients, and child's age and sex, the top quartile of second-trimester choline intake was associated with a child WRAML2 score 1.4 points higher (95% confidence interval: 0.5, 2.4) than the bottom quartile (P-trend = 0.003). Results for first-trimester intake were in the same direction but weaker. Intake of the other nutrients was not associated with the cognitive tests administered. Higher gestational choline intake was associated with modestly better child visual memory at age 7 years. PMID:23425631

  15. Effect of dimethylaminoethanol, an inhibitor of betaine production, on the disposition of choline in the rat kidney

    SciTech Connect

    Lohr, J.; Acara, M. )

    1990-01-01

    The choline metabolite betaine has been shown to be an important organic osmoregulatory solute in the kidney. The isolated perfused rat kidney and kidney slice incubations were used to investigate the effect of 2-dimethylaminoethanol (DMAE), a choline oxidase inhibitor, on the renal excretion and metabolism of choline. In the isolated perfused kidney, ({sup 14}C)choline, at an initial perfusate concentration of 300 microM, was effectively removed from the perfusate over 25 min, with nearly all the {sup 14}C in the perfusate accounted for by betaine during the remainder of the 90-min perfusion. DMAE at concentrations of 3.0 or 5.0 mM significantly decreased the rate of removal of ({sup 14}C)choline from the perfusate and the rate of addition of ({sup 14}C)betaine to the perfusate, yet (14C)betaine remained the only metabolite of choline in perfusate and urine. In kidney tissue slice experiments, conversion of ({sup 14}C)choline to ({sup 14}C)betaine was found in cortical, outer medullary and inner medullary regions of rat kidney. DMAE at 5.0 mM significantly inhibited ({sup 14}C)betaine production in each of the three regions studied. These data show that DMAE is an effective inhibitor of betaine production by the kidney and, as such, may be an important agent for the study of osmoregulation by the kidney.

  16. CHOLINE PARTIALLY PREVENTS THE IMPACT OF ETHANOL ON THE LIPID RAFT DEPENDENT FUNCTIONS OF L1 CELL ADHESION MOLECULE

    PubMed Central

    Tang, Ningfeng; Bamford, Penny; Jones, Jace; He, Min; Kane, Maureen A.; Mooney, Sandra M.; Bearer, Cynthia F.

    2014-01-01

    Background Fetal Alcohol Spectrum Disorder, the leading known cause of mental retardation, is caused by alcohol exposure during pregnancy. One mechanism of ethanol teratogenicity is the disruption of the function of L1 cell adhesion molecule (L1). These functions include enhancement of neurite outgrowth, trafficking through lipid rafts, and signal transduction. Recent data have shown that choline supplementation of rat pups reduces the effects of ethanol on neurobehavior. We sought to determine if choline could prevent the effect of ethanol on L1 function using a simple experimental system. Methods Cerebellar granule neurons (CGN) from postnatal day 6 rat pups were cultured with and without supplemental choline, and the effects on L1 signaling, lipid raft distribution and neurite outgrowth were measured in the presence or absence of ethanol. Results Choline significantly reduced the effect of ethanol on L1 signaling, the distribution of L1 in lipid rafts and L1 mediated neurite outgrowth. However, choline supplemented ethanol exposed cultures remained significantly different than controls. Conclusions Choline pretreatment of CGN significantly reduces the disruption of L1 function by ethanol, but does not completely return L1 function to baseline. This experimental system will enable discovery of the mechanism of the neuroprotective effect of choline. PMID:25421509

  17. Role of central arginine vasopressin receptors in the analgesic effect of CDP-choline on acute and neuropathic pain.

    PubMed

    Bagdas, Deniz; Yucel-Ozboluk, Hasret; Orhan, Fulya; Kanat, Ozkan; Isbil-Buyukcoskun, Naciye; Gurun, Mine S

    2013-12-01

    Recent studies have demonstrated that arginine vasopressin (AVP) plays a crucial role in pain modulation. In addition, our previous studies have proven that centrally administered cytidine-5'-diphosphate-choline (CDP-choline; citicoline) elicits an analgesic effect in different pain models in rats. Given that CDP-choline enhances central and peripheral vasopressin levels, the present study was designed to investigate the role of central AVP receptors in the analgesic effect of CDP-choline in acute and chronic constriction injury-induced neuropathic pain models. For this purpose, rats were pretreated intracerebroventricularly with the AVP V1 or AVP V2 receptor antagonist 15 min before intracerebroventricular injection of CDP-choline or saline, and pain threshold was determined using the Randall-Selitto test. AVP V1 and AVP V2 receptor antagonist blocked the CDP-choline-induced analgesic effect either in acute or neuropathic models of pain in rats. These results suggest, for the first time, that central AVP receptors are involved in the CDP-choline-elicited analgesic effect. PMID:24089014

  18. Micromolar-Affinity Benzodiazepine Receptors Regulate Voltage-Sensitive Calcium Channels in Nerve Terminal Preparations

    NASA Astrophysics Data System (ADS)

    Taft, William C.; Delorenzo, Robert J.

    1984-05-01

    Benzodiazepines in micromolar concentrations significantly inhibit depolarization-sensitive Ca2+ uptake in intact nerve-terminal preparations. Benzodiazepine inhibition of Ca2+ uptake is concentration dependent and stereospecific. Micromolar-affinity benzodiazepine receptors have been identified and characterized in brain membrane and shown to be distinct from nanomolar-affinity benzodiazepine receptors. Evidence is presented that micromolar, and not nanomolar, benzodiazepine binding sites mediate benzodiazepine inhibition of Ca2+ uptake. Irreversible binding to micromolar benzodiazepine binding sites also irreversibly blocked depolarization-dependent Ca2+ uptake in synaptosomes, indicating that these compounds may represent a useful marker for identifying the molecular components of Ca2+ channels in brain. Characterization of benzodiazepine inhibition of Ca2+ uptake demonstrates that these drugs function as Ca2+ channel antagonists, because benzodiazepines effectively blocked voltage-sensitive Ca2+ uptake inhibited by Mn2+, Co2+, verapamil, nitrendipine, and nimodipine. These results indicate that micromolar benzodiazepine binding sites regulate voltage-sensitive Ca2+ channels in brain membrane and suggest that some of the neuronal stabilizing effects of micromolar benzodiazepine receptors may be mediated by the regulation of Ca2+ conductance.

  19. Characterization and Detection of a Widely Distributed Gene Cluster That Predicts Anaerobic Choline Utilization by Human Gut Bacteria

    PubMed Central

    Martínez-del Campo, Ana; Bodea, Smaranda; Hamer, Hilary A.; Marks, Jonathan A.; Haiser, Henry J.; Turnbaugh, Peter J.

    2015-01-01

    ABSTRACT Elucidation of the molecular mechanisms underlying the human gut microbiota’s effects on health and disease has been complicated by difficulties in linking metabolic functions associated with the gut community as a whole to individual microorganisms and activities. Anaerobic microbial choline metabolism, a disease-associated metabolic pathway, exemplifies this challenge, as the specific human gut microorganisms responsible for this transformation have not yet been clearly identified. In this study, we established the link between a bacterial gene cluster, the choline utilization (cut) cluster, and anaerobic choline metabolism in human gut isolates by combining transcriptional, biochemical, bioinformatic, and cultivation-based approaches. Quantitative reverse transcription-PCR analysis and in vitro biochemical characterization of two cut gene products linked the entire cluster to growth on choline and supported a model for this pathway. Analyses of sequenced bacterial genomes revealed that the cut cluster is present in many human gut bacteria, is predictive of choline utilization in sequenced isolates, and is widely but discontinuously distributed across multiple bacterial phyla. Given that bacterial phylogeny is a poor marker for choline utilization, we were prompted to develop a degenerate PCR-based method for detecting the key functional gene choline TMA-lyase (cutC) in genomic and metagenomic DNA. Using this tool, we found that new choline-metabolizing gut isolates universally possessed cutC. We also demonstrated that this gene is widespread in stool metagenomic data sets. Overall, this work represents a crucial step toward understanding anaerobic choline metabolism in the human gut microbiota and underscores the importance of examining this microbial community from a function-oriented perspective. PMID:25873372

  20. Centrally administered CDP-choline induced cardiovascular responses are mediated by activation of the central phospholipase-prostaglandin signaling cascade.

    PubMed

    Topuz, Bora B; Altinbas, Burcin; Ilhan, Tuncay; Yilmaz, Mustafa S; Erdost, Hatice; Saha, Sikha; Savci, Vahide; Yalcin, Murat

    2014-05-14

    The present study was designed to determine the involvement of central prostaglandin synthesis on the pressor and bradycardic effect of cytidine 5'-diphosphocholine (CDP-choline). Intracerebroventricular (i.c.v.) administration of CDP-choline was made and blood pressure and heart rate were recorded in male Sprague Dawley rats throughout this study. Microdialysis and immunohistochemical studies were performed to measure extracellular total prostaglandin concentration and to show cyclooxygenase-1 and -2 (COX-1 and -2) immunoreactivities, respectively, in the posterior hypothalamic area. Moreover, rats were pretreated (i.c.v) with mepacrine [a phospholipase A2 (PLA2) inhibitor], ibuprofen [a nonselective COX inhibitor], neomycine [a phospholipase C (PLC) inhibitor] or furegrelate [a thromboxane A2 (TXA2) synthesis inhibitor] 5 min prior to the injection of CDP-choline to determine the effects of these inhibitors on cardiovascular responses to CDP-choline. Control rats were pretreated (i.c.v) with saline. CDP-choline caused a dose- and time-dependent increase in blood pressure and decrease in heart rate. Immunohistochemical studies showed that CDP-choline increased COX-1 and -2 immunoreactivities in the posterior hypothalamic area. CDP-choline also elevated hypothalamic extracellular total prostaglandin concentration by 62%, as shown in microdialysis studies. Mepacrine or ibuprofen pretreatments almost completely blocked the pressor and bradycardic responses to CDP-choline while neomycine or furegrelate partially attenuated the drug-induced cardiovascular effects. The results suggest that CDP-choline may stimulate prostaglandin synthesis through the activation of PLA2, cyclooxygenases (COX-1 and -2) and prostaglandins and at least TXA2, may mediate the drug׳s cardiovascular effects. PMID:24704528

  1. Usual choline and betaine dietary intake and incident coronary heart disease: the Atherosclerosis Risk in Communities (ARIC) Study

    PubMed Central

    Bidulescu, Aurelian; Chambless, Lloyd E; Siega-Riz, Anna Maria; Zeisel, Steven H; Heiss, Gerardo

    2007-01-01

    Background Low dietary intake of the essential nutrient choline and its metabolite betaine may increase atherogenesis both through effects on homocysteine methylation pathways as well as through choline's antioxidants properties. Nutrient values for many common foods for choline and betaine have recently become available in the U.S. nutrient composition database. Our objective was to assess the association of dietary intake of choline and betaine with incident coronary heart disease (CHD), adjusting for dietary intake measurement error. Methods We conducted a prospective investigation of the relation between usual intake of choline and betaine with the risk of CHD in 14,430 middle-aged men and women of the biethnic Atherosclerosis Risk in Communities study. A semi-quantitative food frequency questionnaire was used to assess nutrient intake. Proportional hazard regression models were used to calculate the risk of incident CHD. A regression calibration method was used to adjust for measurement error. Results During an average 14 years of follow-up (1987–2002), 1,072 incident CHD events were documented. Compared with the lowest quartile of intake, incident CHD risk was slightly and non-significantly higher in the highest quartile of choline and choline plus betaine, HR = 1.22 (0.91, 1.64) and HR = 1.14 (0.85, 1.53), controlling for age, sex, education, total energy intake, dietary intakes of folate, methionine and vitamin B6. No association was found between dietary choline intake and incident CHD when correcting for measurement error. Conclusion Higher intakes of choline and betaine were not protective for incident CHD. Similar investigations in other populations are of interest. PMID:17629908

  2. Uptake As Language Awareness.

    ERIC Educational Resources Information Center

    Ellis, Rod

    1995-01-01

    Investigates the sincerity and validity of uptake as a measure of language learning by comparing the words students report they have learned after completing a listening task with the words they score correctly on a translation test. Results indicate that whereas uptake may have construct validity, its concurrent validity is uncertain. (16…

  3. ( sup 14 C)-Sucrose uptake by guard cell protoplasts of pisum sativum, argenteum mutant

    SciTech Connect

    Rohrig, K.; Raschke, K. )

    1991-05-01

    Guard cells rely on import for their supply with reduced carbon. The authors tested by silicone oil centrifugation the ability of guard cell protoplasts to accumulated ({sup 14}C)-sucrose. Uptake rates were corrected after measurement of {sup 14}C-sorbitol and {sup 3}H{sub 2}O spaces. Sucrose uptake followed biphasic kinetics, with a high-affinity component below 1 mM external sucrose (apparent K{sub m} 0.8 mM at 25C) and a low-affinity nonsaturable component above. Uptake depended on pH (optimum at pH 5.0). Variations in the concentrations of external KCl, CCCP, and valinomycin indicated that about one-half of the sucrose uptake rate could be related to an electrochemical gradient across the plasmalemma. Total uptake rates measured at 5 mM external sucrose seem to be sufficient to replenish emptied plastids with starch within a few hours.

  4. Nanoparticle Surface Affinity as a Predictor of Trophic Transfer.

    PubMed

    Geitner, Nicholas K; Marinakos, Stella M; Guo, Charles; O'Brien, Niall; Wiesner, Mark R

    2016-07-01

    Nanoscale materials, whether natural, engineered, or incidental, are increasingly acknowledged as important components in large, environmental systems with potential implications for environmental impact and human health. Mathematical models are a useful tool for handling the rapidly increasing complexity and diversity of these materials and their exposure routes. Presented here is a mathematical model of trophic transfer driven by nanomaterial surface affinity for environmental and biological surfaces, developed in tandem with an experimental functional assay for determining these surface affinities. We found that nanoparticle surface affinity is a strong predictor of uptake through predation in a simple food web consisting of the algae Chlorella vulgaris and daphnid Daphnia magna. The mass of nanoparticles internalized by D. magna through consuming nanomaterial-contaminated algae varied linearly with surface-attachment efficiency. Internalized quantities of gold nanoparticles in D. magna ranged from 8.3 to 23.6 ng/mg for nanoparticle preparations with surface-attachment efficiencies ranging from 0.07 to 1. This model, coupled with the functional-assay approach, may provide a useful screening tool for existing materials as well as a predictive model for their development. PMID:27249534

  5. Endoscopic evaluation of the comparative effects of acetylsalicylic acid and choline magnesium trisalicylate on human gastric and duodenal mucosa.

    PubMed

    Kilander, A; Dotevall, G

    1983-02-01

    A new salicylate product, choline magnesium trisalicylate (Trilisate tablets), and acetylsalicylic acid were compared for their local effects in equipotent doses on the gastroduodenal mucosa in a randomized, double-blind, cross-over study, using 10 healthy volunteers. After five-day periods of administration, gastroduodenoscopy was performed and photographs were obtained. All subjects given acetylsalicylic acid developed multiple mucosal lesions, but in only four subjects given choline magnesium trisalicylate were slight mucosal changes noted. Mean serum salicylate levels were similar in the two groups. Our data suggest that the risk of developing mucosal lesions is much less during treatment with choline magnesium trisalicylate than with acetylsalicylic acid. PMID:6337663

  6. Immobilized metal ion affinity chromatography.

    PubMed

    Yip, T T; Hutchens, T W

    1992-01-01

    Immobilized metal ion affinity chromatography (IMAC) (1,2) is also referred to as metal chelate chromatography, metal ion interaction chromatography, and ligand-exchange chromatography. We view this affinity separation technique as an intermediate between highly specific, high-affinity bioaffinity separation methods, and wider spectrum, low-specificity adsorption methods, such as ion exchange. The IMAC stationary phases are designed to chelate certain metal ions that have selectivity for specific groups (e.g., His residues) in peptides (e.g., 3-7) and on protein surfaces (8-13). The number of stationary phases that can be synthesized for efficient chelation of metal ions is unlimited, but the critical consideration is that there must be enough exposure of the metal ion to interact with the proteins, preferably in a biospecific manner. Several examples are presented in Fig. 1. The challenge to produce new immobilized chelating groups, including protein surface metal-binding domains (14,15) is being explored continuously. Table 1 presents a list of published procedures for the synthesis and use of stationary phases with immobilized chelating groups. This is by no means exhaustive, and is intended only to give an idea of the scope and versatility of IMAC. Fig. 1 Schematic illustration of several types of immobilized metal-chelating groups, including, iminodiacetate (IDA), tris(carboxymethyl) ethylenediamine (TED), and the metal-binding peptides (GHHPH)(n)G (where n = 1,2,3, and 5) (14,15). Table 1 Immobilized Chelating Groups and Metal Ions Used for Immobilized Metal Ion Affinity Chromatography Chelating group Suitable metal ions Reference Commercial source Immodiacetate Transitional1,2 Pharmacia LKB Pierce Sigma Boehringer Mannheim TosoHaas 2-Hydroxy-3[N-(2- pyrtdylmethyl) glycme]propyl Transitional3 Not available ?-Alky1 mtrilo triacetic acid Transitional4 Not available Carboxymethylated asparhc acid Ca(II)13 Not available Tris (carboxy- methyl) ethylene Diamme

  7. The Interplay of Antigen Affinity, Internalization, and Pharmacokinetics on CD44-Positive Tumor Targeting of Monoclonal Antibodies.

    PubMed

    Glatt, Dylan M; Beckford Vera, Denis R; Parrott, Matthew C; Luft, J Christopher; Benhabbour, S Rahima; Mumper, Russell J

    2016-06-01

    Monoclonal antibodies (mAbs) offer promise as effective tumor targeting and drug delivery agents for cancer therapy. However, comparative biological and clinical characteristics of mAbs targeting the same tumor-associated antigen (TAA) often differ widely. This study examined the characteristics of mAbs that impact tumor targeting using a panel of mAb clones specific to the cancer-associated cell-surface receptor and cancer stem cell marker CD44. CD44 mAbs were screened for cell-surface binding, antigen affinity, internalization, and CD44-mediated tumor uptake by CD44-positive A549 cells. It was hypothesized that high-affinity, rapidly internalizing CD44 mAbs would result in high tumor uptake and prolonged tumor retention. Although high-affinity clones rapidly bound and were internalized by A549 cells in vitro, an intermediate-affinity clone demonstrated significantly greater tumor uptake and retention than high-affinity clones in vivo. Systemic exposure, rather than high antigen affinity or rapid internalization, best associated with tumor targeting of CD44 mAbs in A549 tumor-bearing mice. PMID:27079967

  8. Intravenously injected CDP-choline increases blood pressure and reverses hypotension in haemorrhagic shock: effect is mediated by central cholinergic activation.

    PubMed

    Savci, Vahide; Goktalay, Gokhan; Cansev, Mehmet; Cavun, Sinan; Yilmaz, M Sertac; Ulus, Ismail H

    2003-05-01

    Intravenous (i.v.) administration of cytidine-5'-diphosphate choline (CDP-choline) (100, 250 and 500 mg/kg) increased blood pressure in normal rats and reversed hypotension in haemorrhagic shock. Choline (54 mg/kg; i.v.), at the dose equimolar to 250 mg/kg CDP-choline decreased blood pressure of rats in both conditions and caused the death of all hypotensive animals within 2-5 min. Equimolar dose of cytidine (124 mg/kg; i.v.) did not change cardiovascular parameters. Choline levels in plasma, lateral cerebral ventricle and hypothalamus increased after CDP-choline administration. Intracerebroventricular (i.c.v.) hemicholinium-3 pretreatment (20 microg), greatly attenuated the pressor effect of CDP-choline in both conditions. Atropine pretreatment (10 microg; i.c.v.) did not change the pressor effect of CDP-choline while mecamylamine (50 microg; i.c.v.) abolished the pressor response to drug. Besides, acetylcholine (1 micromol; i.c.v.) produced similar increases in blood pressure in normal and hypotensive conditions to that observed in CDP-choline given rats. CDP-choline (250 mg/kg; i.v.) increased plasma catecholamines and vasopressin levels but not plasma renin activity. Pretreatment of rats with either prazosin (0.5 mg/kg; i.v.) or vasopressin V(1) receptor antagonist, [beta-mercapto,beta,beta-cyclopentamethylenepropionyl(1),O-Me-Tyr(2)-Arg(8)]vasopressin (10 microg/kg; i.v.), attenuated the pressor response to CDP-choline while simultaneous administration of these antagonists before CDP-choline injection completely blocked the pressor effect. Results show that i.v. CDP-choline increases blood pressure and reverses hypotension in haemorrhagic shock. Activation of central nicotinic cholinergic mechanisms by the increases in plasma and brain choline concentrations appears to be involved in the pressor effect of this drug. Moreover, the increases in plasma catecholamines and vasopressin levels mediate these effects. PMID:12742520

  9. Maternal choline supplementation programs greater activity of the phosphatidylethanolamine N-methyltransferase (PEMT) pathway in adult Ts65Dn trisomic mice.

    PubMed

    Yan, Jian; Ginsberg, Stephen D; Powers, Brian; Alldred, Melissa J; Saltzman, Arthur; Strupp, Barbara J; Caudill, Marie A

    2014-10-01

    Maternal choline supplementation (MCS) induces lifelong cognitive benefits in the Ts65Dn mouse, a trisomic mouse model of Down syndrome and Alzheimer's disease. To gain insight into the mechanisms underlying these beneficial effects, we conducted a study to test the hypothesis that MCS alters choline metabolism in adult Ts65Dn offspring. Deuterium-labeled methyl-d9-choline was administered to adult Ts65Dn and disomic (2N) female littermates born to choline-unsupplemented or choline-supplemented Ts65Dn dams. Enrichment of d9-choline metabolites (derived from intact choline) and d3 + d6-choline metabolites [produced when choline-derived methyl groups are used by phosphatidylethanolamine N-methyltransferase (PEMT)] was measured in harvested tissues. Adult offspring (both Ts65Dn and 2N) of choline-supplemented (vs. choline-unsupplemented) dams exhibited 60% greater (P≤0.007) activity of hepatic PEMT, which functions in de novo choline synthesis and produces phosphatidylcholine (PC) enriched in docosahexaenoic acid. Higher (P<0.001) enrichment of PEMT-derived d3 and d6 metabolites was detected in liver, plasma, and brain in both genotypes but to a greater extent in the Ts65Dn adult offspring. MCS also yielded higher (P<0.05) d9 metabolite enrichments in liver, plasma, and brain. These data demonstrate that MCS exerts lasting effects on offspring choline metabolism, including up-regulation of the hepatic PEMT pathway and enhanced provision of choline and PEMT-PC to the brain. PMID:24963152

  10. Hexadecylphosphocholine inhibits phosphatidylcholine synthesis via both the methylation of phosphatidylethanolamine and CDP-choline pathways in HepG2 cells.

    PubMed

    Jiménez-López, José M; Carrasco, María P; Segovia, Josefa L; Marco, Carmen

    2004-01-01

    We reported in a recent publication that hexadecylphosphocholine (HePC), a lysophospholipid analogue, reduces cell proliferation in HepG2 cells and at the same time inhibits the biosynthesis of phosphatidylcholine (PC) via CDP-choline by acting upon CTP:phosphocholine cytidylyltransferase (CT). We describe here the results of our study into the influence of HePC on other biosynthetic pathways of glycerolipids. HePC clearly decreased the incorporation of the exogenous precursor [1,2,3-3H]glycerol into PC and phosphatidylserine (PS) whilst increasing that of the neutral lipids diacylglycerol (DAG) and triacylglycerol (TAG). Interestingly, the uptake of L-[3-3H]serine into PS and other phospholipids remained unchanged by HePC and neither was the activity of either PS synthase or PS decarboxylase altered, demonstrating that the biosynthesis of PS is unaffected by HePC. We also analyzed the water-soluble intermediates and final product of the CDP-ethanolamine pathway and found that HePC caused an increase in the incorporation of [1,2-14C]ethanolamine into CDP-ethanolamine and phosphatidylethanolamine (PE) and a decrease in ethanolamine phosphate, which might be interpreted in terms of a stimulation of CTP:phosphoethanolamine cytidylyltransferase activity. Since PE can be methylated to give PC, we studied this process further and observed that HePC decreased the synthesis of PC from PE by inhibiting the PE N-methyltransferase activity. These results constitute the first experimental evidence that the inhibition of the synthesis of PC via CDP-choline by HePC is not counterbalanced by any increase in its formation via methylation. On the contrary, in the presence of HePC both pathways seem to contribute jointly to a decrease in the overall synthesis of PC in HepG2 cells. PMID:14592540

  11. Characterization of taurine binding, uptake, and release in the rat hypothalamus

    SciTech Connect

    Hanretta, A.T.

    1985-01-01

    The neurotransmitter criteria of specific receptors, inactivation, and release were experimentally examined for taurine in the hypothalamus. Specific membrane binding and synaptosomal uptake of taurine both displayed high affinity and low affinity systems. The neurotransmitter criterion of release was studied in superfused synaptosomes. Exposure of synaptosomes which had been preloaded with a concentration of (/sup 3/H)taurine in the high affinity uptake range (1.5 ..mu..M) to either 56 mM K/sup +/ or 100 ..mu..M veratridine evoked a Ca/sup 2 +/-independent release. Exposure of synaptosomes which had been preloaded with a concentration of (/sup 3/H)taurine in the low affinity uptake range (2 mM) to 56 mM K/sup +/ induced a Ca/sup 2 +/-independent release, whereas 100 /sup +/M veratridine did not, either in the presence or absence of Ca/sup 2 +/. Based on these results, as well as other observations, a model is proposed in which the high affinity uptake system is located on neuronal membranes and the low affinity uptake system is located on glial membranes. The mechanisms of binding, uptake, and release in relation to the cellular location of each are discussed. We conclude that the neurotransmitter criterion of activation by re-uptake is satisfied for taurine in the hypothalamus. However, the failure to demonstrate both a specific taurine receptor site and a Ca/sup 2 +/-dependent evoked release, necessitates that we conclude that taurine appears not to function as a hypothalamic neurotransmitter, at least not in the classical sense.

  12. Indian craniometric variability and affinities.

    PubMed

    Raghavan, Pathmanathan; Bulbeck, David; Pathmanathan, Gayathiri; Rathee, Suresh Kanta

    2013-01-01

    Recently published craniometric and genetic studies indicate a predominantly indigenous ancestry of Indian populations. We address this issue with a fuller coverage of Indian craniometrics than any done before. We analyse metrical variability within Indian series, Indians' sexual dimorphism, differences between northern and southern Indians, index-based differences of Indian males from other series, and Indians' multivariate affinities. The relationship between a variable's magnitude and its variability is log-linear. This relationship is strengthened by excluding cranial fractions and series with a sample size less than 30. Male crania are typically larger than female crania, but there are also shape differences. Northern Indians differ from southern Indians in various features including narrower orbits and less pronounced medial protrusion of the orbits. Indians resemble Veddas in having small crania and similar cranial shape. Indians' wider geographic affinities lie with "Caucasoid" populations to the northwest, particularly affecting northern Indians. The latter finding is confirmed from shape-based Mahalanobis-D distances calculated for the best sampled male and female series. Demonstration of a distinctive South Asian craniometric profile and the intermediate status of northern Indians between southern Indians and populations northwest of India confirm the predominantly indigenous ancestry of northern and especially southern Indians. PMID:24455409

  13. Indian Craniometric Variability and Affinities

    PubMed Central

    Raghavan, Pathmanathan; Bulbeck, David; Pathmanathan, Gayathiri; Rathee, Suresh Kanta

    2013-01-01

    Recently published craniometric and genetic studies indicate a predominantly indigenous ancestry of Indian populations. We address this issue with a fuller coverage of Indian craniometrics than any done before. We analyse metrical variability within Indian series, Indians' sexual dimorphism, differences between northern and southern Indians, index-based differences of Indian males from other series, and Indians' multivariate affinities. The relationship between a variable's magnitude and its variability is log-linear. This relationship is strengthened by excluding cranial fractions and series with a sample size less than 30. Male crania are typically larger than female crania, but there are also shape differences. Northern Indians differ from southern Indians in various features including narrower orbits and less pronounced medial protrusion of the orbits. Indians resemble Veddas in having small crania and similar cranial shape. Indians' wider geographic affinities lie with “Caucasoid” populations to the northwest, particularly affecting northern Indians. The latter finding is confirmed from shape-based Mahalanobis-D distances calculated for the best sampled male and female series. Demonstration of a distinctive South Asian craniometric profile and the intermediate status of northern Indians between southern Indians and populations northwest of India confirm the predominantly indigenous ancestry of northern and especially southern Indians. PMID:24455409

  14. Reduced Na+ uptake in the NaCl-hypersensitive sos1 mutant of Arabidopsis thaliana.

    PubMed Central

    Ding, L; Zhu, J K

    1997-01-01

    Sos1 is an Arabidopsis thaliana mutant with > 20 times higher sensitivity toward Na+ inhibition due to a defective high-affinity potassium-uptake system. We report here that sos1 accumulates less Na+ than the wild type in response to NaCl stress. The Na+ contents in sos1 seedlings exposed to 25 mM NaCl for 2 or more d are about 43% lower than those in the wild type. When assayed at 20 mM external NaCl, sos1 seedlings pretreated with low potassium have 32% lower Na+ uptake than the wild type. However, little difference in Na+ uptake could be measured when the seedlings were not pretreated with low potassium. Low-potassium treatment was shown to induce high-affinity potassium-uptake activity in Arabidopsis seedlings. No substantial difference in Na+ efflux between sos1 and the wild type was detected. The results show that the reduced Na+ accumulation in sos1 is due to a lower Na+ influx rate. Therefore, the sos1 mutation appears to disrupt low-affinity Na+ uptake in addition to its impairment of high-affinity K+ uptake. PMID:9085573

  15. Human FABP1 T94A variant enhances cholesterol uptake.

    PubMed

    Huang, Huan; McIntosh, Avery L; Landrock, Kerstin K; Landrock, Danilo; Storey, Stephen M; Martin, Gregory G; Gupta, Shipra; Atshaves, Barbara P; Kier, Ann B; Schroeder, Friedhelm

    2015-07-01

    Although expression of the human liver fatty acid binding protein (FABP1) T94A variant alters serum lipoprotein cholesterol levels in human subjects, nothing is known whereby the variant elicits these effects. This issue was addressed by in vitro cholesterol binding assays using purified recombinant wild-type (WT) FABP1 T94T and T94A variant proteins and in cultured primary human hepatocytes expressing the FABP1 T94T (genotyped as TT) or T94A (genotyped as CC) proteins. The human FABP1 T94A variant protein had 3-fold higher cholesterol-binding affinity than the WT FABP1 T94T as shown by NBD-cholesterol fluorescence binding assays and by cholesterol isothermal titration microcalorimetry (ITC) binding assays. CC variant hepatocytes also exhibited 30% higher total FABP1 protein. HDL- and LDL-mediated NBD-cholesterol uptake was faster in CC variant than TT WT human hepatocytes. VLDL-mediated uptake of NBD-cholesterol did not differ between CC and TT human hepatocytes. The increased HDL- and LDL-mediated NBD-cholesterol uptake was not associated with any significant change in mRNA levels of SCARB1, LDLR, CETP, and LCAT encoding the key proteins in lipoprotein cholesterol uptake. Thus, the increased HDL- and LDL-mediated NBD-cholesterol uptake by CC hepatocytes may be associated with higher affinity of T94A protein for cholesterol and/or increased total T94A protein level. PMID:25732850

  16. Determination of choline in pharmaceutical formulations by reversed-phase high-performance liquid chromatography and postcolumn suppression conductivity detection.

    PubMed

    Chen, S; Soneji, V; Webster, J

    1996-07-19

    Choline is a primary degradation product of succinylcholine chloride. Determination of low concentration choline in succinylcholine chloride bulk drug and formulation is a challenge, due to the lack of sensitive detection methods. A reversed-phase separation method with postcolumn suppression conductivity detection is described for the determination of choline. Hexanesulfonic acid is employed as an ion-pair reagent in the mobile phase, which allows the accomplishment of both reversed-phase separation and a sensitive conductivity detection. Detection sensitivity is significantly enhanced by passing the mobile phase through a postcolumn cation suppressor, where hexanesulfonic acid is removed and the background conductance is reduced. This method is simple and sensitive. No sample derivatization procedure is required. The detection limit for choline is about 10 pmol. PMID:8765854

  17. Three functional transporters for constitutive, diurnally regulated, and starvation-induced uptake of ammonium into Arabidopsis roots.

    PubMed Central

    Gazzarrini, S; Lejay, L; Gojon, A; Ninnemann, O; Frommer, W B; von Wirén, N

    1999-01-01

    Ammonium and nitrate are the prevalent nitrogen sources for growth and development of higher plants. 15N-uptake studies demonstrated that ammonium is preferred up to 20-fold over nitrate by Arabidopsis plants. To study the regulation and complex kinetics of ammonium uptake, we isolated two new ammonium transporter (AMT) genes and showed that they functionally complemented an ammonium uptake-deficient yeast mutant. Uptake studies with 14C-methylammonium and inhibition by ammonium yielded distinct substrate affinities between uptake into plant roots showed that nitrogen supply and time of day differentially regulated the individual carriers. Transcript levels of AtAMT1;1, which possesses an affinity in the nanomolar range, steeply increased with ammonium uptake in roots when nitrogen nutrition became limiting, whereas those of AtAMT1;3 increased slightly, with AtAMT1;2 being more constitutively expressed. All three ammonium transporters showed diurnal variation in expression, but AtAMT1;3 transcript levels peaked with ammonium uptake at the end of the light period, suggesting that AtAMT1;3 provides a link between nitrogen assimilation and carbon provision in roots. Our results show that high-affinity ammonium uptake in roots is regulated in relation to the physiological status of the plant at the transcriptional level and by substrate affinities of individual members of the AMT1 gene family. PMID:10330477

  18. Early Second Trimester Maternal Plasma Choline and Betaine Are Related to Measures of Early Cognitive Development in Term Infants

    PubMed Central

    Wu, Brian T. F.; Dyer, Roger A.; King, D. Janette; Richardson, Kelly J.; Innis, Sheila M.

    2012-01-01

    Background The importance of maternal dietary choline for fetal neural development and later cognitive function has been well-documented in experimental studies. Although choline is an essential dietary nutrient for humans, evidence that low maternal choline in pregnancy impacts neurodevelopment in human infants is lacking. We determined potential associations between maternal plasma free choline and its metabolites betaine and dimethylglycine in pregnancy and infant neurodevelopment at 18 months of age. Methodology This was a prospective study of healthy pregnant women and their full-term, single birth infants. Maternal blood was collected at 16 and 36 weeks of gestation and infant neurodevelopment was assessed at 18 months of age for 154 mother-infant pairs. Maternal plasma choline, betaine, dimethylglycine, methionine, homocysteine, cysteine, total B12, holotranscobalamin and folate were quantified. Infant neurodevelopment was evaluated using the Bayley Scales of Infant Development–III. Multivariate regression, adjusting for covariates that impact development, was used to determine the associations between maternal plasma choline, betaine and dimethylglycine and infant neurodevelopment. Results The maternal plasma free choline at 16 and 36 weeks gestation was median (interquartile range) 6.70 (5.78–8.03) and 9.40 (8.10–11.3) µmol/L, respectively. Estimated choline intakes were (mean ±SD) 383±98.6 mg/day, and lower than the recommended 450 mg/day. Betaine intakes were 142±70.2 mg/day. Significant positive associations were found between infant cognitive test scores and maternal plasma free choline (B = 6.054, SE = 2.283, p = 0.009) and betaine (B = 7.350, SE = 1.933, p = 0.0002) at 16 weeks of gestation. Maternal folate, total B12, or holotranscobalamin were not related to infant development. Conclusion We show that choline status in the first half of pregnancy is associated with cognitive development among healthy term gestation

  19. Prognostic value of choline and betaine depends on intestinal microbiota-generated metabolite trimethylamine-N-oxide

    PubMed Central

    Wang, Zeneng; Tang, W. H. Wilson; Buffa, Jennifer A.; Fu, Xiaoming; Britt, Earl B.; Koeth, Robert A.; Levison, Bruce S.; Fan, Yiying; Wu, Yuping; Hazen, Stanley L.

    2014-01-01

    Aims Recent metabolomics and animal model studies show trimethylamine-N-oxide (TMAO), an intestinal microbiota-dependent metabolite formed from dietary trimethylamine-containing nutrients such as phosphatidylcholine (PC), choline, and carnitine, is linked to coronary artery disease pathogenesis. Our aim was to examine the prognostic value of systemic choline and betaine levels in stable cardiac patients. Methods and results We examined the relationship between fasting plasma choline and betaine levels and risk of major adverse cardiac events (MACE = death, myocardial infraction, stroke) in relation to TMAO over 3 years of follow-up in 3903 sequential stable subjects undergoing elective diagnostic coronary angiography. In our study cohort, median (IQR) TMAO, choline, and betaine levels were 3.7 (2.4–6.2)μM, 9.8 (7.9–12.2)μM, and 41.1 (32.5–52.1)μM, respectively. Modest but statistically significant correlations were noted between TMAO and choline (r = 0.33, P < 0.001) and less between TMAO and betaine (r = 0.09, P < 0.001). Higher plasma choline and betaine levels were associated with a 1.9-fold and 1.4-fold increased risk of MACE, respectively (Quartiles 4 vs. 1; P < 0.01, each). Following adjustments for traditional cardiovascular risk factors and high-sensitivity C-reactive protein, elevated choline [1.34 (1.03–1.74), P < 0.05], and betaine levels [1.33 (1.03–1.73), P < 0.05] each predicted increased MACE risk. Neither choline nor betaine predicted MACE risk when TMAO was added to the adjustment model, and choline and betaine predicted future risk for MACE only when TMAO was elevated. Conclusion Elevated plasma levels of choline and betaine are each associated with incident MACE risk independent of traditional risk factors. However, high choline and betaine levels are only associated with higher risk of future MACE with concomitant increase in TMAO. PMID:24497336

  20. Maternal choline supplementation differentially alters the basal forebrain cholinergic system of young-adult Ts65Dn and disomic mice

    PubMed Central

    Kelley, Christy M.; Powers, Brian E.; Velazquez, Ramon; Ash, Jessica A.; Ginsberg, Stephen D.; Strupp, Barbara J.; Mufson, Elliott J.

    2014-01-01

    Down syndrome (DS), trisomy 21, is a multifaceted condition marked by intellectual disability and early presentation of Alzheimer’s disease (AD) neuropathological lesions including degeneration of the basal forebrain cholinergic neuron (BFCN) system. While DS is diagnosable during gestation, there is no treatment option for expectant mothers or DS individuals. Using the Ts65Dn mouse model of DS that displays age-related degeneration of the BFCN system, we investigated the effects of maternal choline supplementation on the BFCN system in adult Ts65Dn mice and disomic (2N) littermates at 4.3–7.5 mos of age. Ts65Dn dams were maintained on a choline supplemented diet (5.1 g/kg choline chloride) or a control, unsupplemented diet with adequate amounts of choline (1 g/kg choline chloride) from conception until weaning of offspring; postweaning, offspring were fed the control diet. Mice were transcardially perfused with paraformaldehyde, brains were sectioned, and immunolabeled for choline acetyltransferase (ChAT) or p75-neurotrophin receptor (p75NTR). BFCN number and size, the area of the regions, and the intensity of hippocampal labeling were determined. Ts65Dn unsupplemented mice displayed region- and immunolabel-dependent increased BFCN number, larger areas, smaller BFCNs, and overall increased hippocampal ChAT intensity compared with 2N unsupplemented mice. These effects were partially normalized by maternal choline supplementation. Taken together, the results suggest a developmental imbalance in the Ts65Dn BFCN system. Early maternal-diet choline supplementation attenuates some of the genotype-dependent alterations in the BFCN system, suggesting this naturally occurring nutrient as a treatment option for pregnant mothers with knowledge that their offspring is trisomy 21. PMID:24178831

  1. Radioactive iodine uptake

    MedlinePlus

    ... uptake may be due to: Factitious hyperthyroidism Iodine overload Subacute thyroiditis Silent (or painless) thyroiditis Amiodarone Risks ... to achieve this important distinction for online health information and services. Learn more about A.D.A. ...

  2. Affine hypersurfaces with parallel difference tensor relative to affine α-connection

    NASA Astrophysics Data System (ADS)

    Li, Cece

    2014-12-01

    Li and Zhang (2014) studied affine hypersurfaces of R n + 1 with parallel difference tensor relative to the affine α-connection ∇ (α), and characterized the generalized Cayley hypersurfaces by K n - 1 ≠ 0 and ∇ (α) K = 0 for some nonzero constant α, where the affine α-connection ∇ (α) of information geometry was introduced on affine hypersurface. In this paper, by a slightly different method we continue to study affine hypersurfaces with ∇ (α) K = 0, if α = 0 we further assume that the Pick invariant vanishes and affine metric is of constant sectional curvature. It is proved that they are either hyperquadrics or improper affine hypersphere with flat indefinite affine metric, the latter can be locally given as a graph of a polynomial of at most degree n + 1 with constant Hessian determinant. In particular, if the affine metric is definite, Lorentzian, or its negative index is 2, we complete the classification of such hypersurfaces.

  3. Comparative Physiological Evidence that β-Alanine Betaine and Choline-O-Sulfate Act as Compatible Osmolytes in Halophytic Limonium Species 1

    PubMed Central

    Hanson, Andrew D.; Rathinasabapathi, Bala; Chamberlin, Beverly; Gage, Douglas A.

    1991-01-01

    The quaternary ammonium compounds accumulated in saline conditions by five salt-tolerant species of Limonium (Plumbaginaceae) were analyzed by fast atom bombardment mass spectrometry. Three species accumulated β-alanine betaine and choline-O-sulfate; the others accumulated glycine betaine and choline-O-sulfate. Three lines of evidence indicated that β-alanine betaine and choline-O-sulfate replace glycine betaine as osmo-regulatory solutes. First, tests with bacteria showed that β-alanine betaine and choline-O-sulfate have osmoprotective properties comparable to glycine betaine. Second, when β-alanine betaine and glycine betaine accumulators were salinized, the levels of their respective betaines, plus that of choline-O-sulfate, were closely correlated with leaf solute potential. Third, substitution of sulfate for chloride salinity caused an increase in the level of choline-O-sulfate and a matching decrease in glycine betaine level. Experiments with 14C-labeled precursors established that β-alanine betaine accumulators did not synthesize glycine betaine and vice versa. These experiments also showed that β-alanine betaine synthesis occurs in roots as well as leaves of β-alanine betaine accumulators and that choline-O-sulfate and glycine betaine share choline as a precursor. Unlike glycine betaine, β-alanine betaine synthesis cannot interfere with conjugation of sulfate to choline by competing for choline and does not require oxygen. These features of β-alanine betaine may be advantageous in sulfate-rich salt marsh environments. PMID:16668509

  4. Choline magnesium trisalicylate: comparative pharmacokinetic study of once-daily and twice-daily dosages.

    PubMed

    Levitt, M J; Kann, J

    1984-07-01

    This randomized crossover study compared the pharmacokinetics of choline magnesium trisalicylate tablets administered once daily (3000 mg of salicylate) or twice daily (1500 mg of salicylate) for six d. Serum salicylate levels were measured by HPLC. Mean "trough" concentrations fell within the therapeutic range (5-30 mg/dL) with either regimen and were relatively constant, indicating that the steady state had been reached. The 24-h area under the salicylate curve (AUC0-24 h) after the final 3000-mg salicylate dose averaged about twice the mean 12-h AUC after the last 1500-mg dose, indicating that the two dosing regimens were equally bioavailable. Clinical observations and results of laboratory safety studies indicate that both dosage schedules of the drug are well tolerated. The present findings support the once-daily therapeutic use of choline magnesium trisalicylate. PMID:6470965

  5. Langevin dynamics of the choline head group in a membrane environment.

    PubMed Central

    Konstant, P H; Pearce, L L; Harvey, S C

    1994-01-01

    Computer simulations of dipalmitoylphosphatidylcholine (DPPC) have been performed using Langevin dynamics and a Marcelja-type mean field. This work has focused on the dynamics of the choline head group to parameterize the empirical constraints against phosphorus-carbon dipolar couplings (Dp-c) as measured by nuclear magnetic resonance (13C-NMR). The results show good agreement with experimental values at constraints equivalent to the choline tilt observed in joint refinement of x-ray diffraction and neutron diffraction scatterings. Quadrupolar splittings for the alpha and beta positions are also calculated and compared with 2H-NMR experiments. The model predicts torsional transition rates around the alpha-beta bonds and for the two C-O-P-O torsions. It also predicts T1 relaxation times for the alpha and beta carbons. PMID:7948684

  6. Kinesin-II Is Required for Axonal Transport of Choline Acetyltransferase in Drosophila

    PubMed Central

    Ray, Krishanu; Perez, Sharon E.; Yang, Zhaohuai; Xu, Jenny; Ritchings, Bruce W.; Steller, Hermann; Goldstein, Lawrence S.B.

    1999-01-01

    KLP64D and KLP68D are members of the kinesin-II family of proteins in Drosophila. Immunostaining for KLP68D and ribonucleic acid in situ hybridization for KLP64D demonstrated their preferential expression in cholinergic neurons. KLP68D was also found to accumulate in cholinergic neurons in axonal obstructions caused by the loss of kinesin light chain. Mutations in the KLP64D gene cause uncoordinated sluggish movement and death, and reduce transport of choline acetyltransferase from cell bodies to the synapse. The inviability of KLP64D mutations can be rescued by expression of mammalian KIF3A. Together, these data suggest that kinesin-II is required for the axonal transport of a soluble enzyme, choline acetyltransferase, in a specific subset of neurons in Drosophila. Furthermore, the data lead to the conclusion that the cargo transport requirements of different classes of neurons may lead to upregulation of specific pathways of axonal transport. PMID:10545496

  7. AzoCholine Enables Optical Control of Alpha 7 Nicotinic Acetylcholine Receptors in Neural Networks.

    PubMed

    Damijonaitis, Arunas; Broichhagen, Johannes; Urushima, Tatsuya; Hüll, Katharina; Nagpal, Jatin; Laprell, Laura; Schönberger, Matthias; Woodmansee, David H; Rafiq, Amir; Sumser, Martin P; Kummer, Wolfgang; Gottschalk, Alexander; Trauner, Dirk

    2015-05-20

    Nicotinic acetylcholine receptors (nAChRs) are essential for cellular communication in higher organisms. Even though a vast pharmacological toolset to study cholinergic systems has been developed, control of endogenous neuronal nAChRs with high spatiotemporal precision has been lacking. To address this issue, we have generated photoswitchable nAChR agonists and re-evaluated the known photochromic ligand, BisQ. Using electrophysiology, we found that one of our new compounds, AzoCholine, is an excellent photoswitchable agonist for neuronal α7 nAChRs, whereas BisQ was confirmed to be an agonist for the muscle-type nAChR. AzoCholine could be used to modulate cholinergic activity in a brain slice and in dorsal root ganglion neurons. In addition, we demonstrate light-dependent perturbation of behavior in the nematode, Caenorhabditis elegans. PMID:25741856

  8. Choline Chloride Catalyzed Amidation of Fatty Acid Ester to Monoethanolamide: A Green Approach.

    PubMed

    Patil, Pramod; Pratap, Amit

    2016-01-01

    Choline chloride catalyzed efficient method for amidation of fatty acid methyl ester to monoethanolamide respectively. This is a solvent free, ecofriendly, 100% chemo selective and economically viable path for alkanolamide synthesis. The Kinetics of amidation of methyl ester were studied and found to be first order with respect to the concentration of ethanolamine. The activation energy (Ea) for the amidation of lauric acid methyl ester catalyzed by choline chloride was found to be 50.20 KJ mol(-1). The 98% conversion of lauric acid monoethanolamide was obtained at 110°C in 1 h with 6% weight of catalyst and 1:1.5 molar ratio of methyl ester to ethanolamine under nitrogen atmosphere. PMID:26666271

  9. The maximal affinity of ligands

    PubMed Central

    Kuntz, I. D.; Chen, K.; Sharp, K. A.; Kollman, P. A.

    1999-01-01

    We explore the question of what are the best ligands for macromolecular targets. A survey of experimental data on a large number of the strongest-binding ligands indicates that the free energy of binding increases with the number of nonhydrogen atoms with an initial slope of ≈−1.5 kcal/mol (1 cal = 4.18 J) per atom. For ligands that contain more than 15 nonhydrogen atoms, the free energy of binding increases very little with relative molecular mass. This nonlinearity is largely ascribed to nonthermodynamic factors. An analysis of the dominant interactions suggests that van der Waals interactions and hydrophobic effects provide a reasonable basis for understanding binding affinities across the entire set of ligands. Interesting outliers that bind unusually strongly on a per atom basis include metal ions, covalently attached ligands, and a few well known complexes such as biotin–avidin. PMID:10468550

  10. Competitive antagonism of fluorescent gentamicin uptake in the cochlea.

    PubMed

    Wang, Qi; Kachelmeier, Allan; Steyger, P S

    2010-09-01

    Aminoglycosides enter inner ear hair cells via apical endocytosis, or mechanoelectrical transduction channels, implying that, in vivo, aminoglycosides enter hair cells from endolymph prior to exerting their cytotoxic effect. If so, circulating aminoglycosides likely cross the strial blood-labyrinth barrier and enter marginal cells prior to clearance into endolymph. We characterized the competitive antagonism of unconjugated aminoglycosides on the uptake of fluorescent gentamicin (GTTR) in the stria vascularis and kidney cells at an early time point. In mice, uptake of GTTR by kidney proximal tubule cells was competitively antagonized by gentamicin at all doses, but only weakly by kanamycin (mimicking in vitro data). GTTR fluorescence was approximately 100-fold greater in proximal tubule cells than in the stria vascularis. Furthermore, only high molar ratios of aminoglycosides significantly reduced strial uptake of GTTR. Thus, gentamicin antagonism of GTTR uptake is more efficacious in proximal tubules than in the stria vascularis. Competitive antagonism of GTTR uptake is indicative of specific cell-regulatable uptake mechanisms (e.g., ion channels, transporters) in the kidney. Strial uptake mechanisms have lower specific affinity for gentamicin, and/or density (compared to the kidney), yet may be critical to transport gentamicin across the strial blood-labyrinth barrier into marginal cells. PMID:20561573

  11. Reduced myo-inositol and total choline measured with cerebral MRS in acute thyrotoxic Graves' disease.

    PubMed

    Elberling, T V; Danielsen, E R; Rasmussen, A K; Feldt-Rasmussen, U; Waldemar, G; Thomsen, C

    2003-01-14

    Neuropsychiatric symptoms in the acute thyrotoxic phase of Graves' disease suggest involvement of brain processes. Short-echo-time proton MRS was used to measure the cerebral metabolite profile in newly diagnosed and untreated Graves' disease. Sixteen patients with Graves' disease and 18 age- and sex-matched healthy volunteers were studied. The patients had significantly reduced total choline and myo-inositol in the acute phase of Graves' thyrotoxicosis compared with the healthy volunteers. PMID:12525741

  12. 75 FR 53577 - Choline hydroxide; Exemption from the Requirement of a Tolerance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-01

    ...This regulation establishes an exemption from the requirement of a tolerance for residues of choline hydroxide (CAS Reg. No. 123-41- 1) when used as an inert ingredient that acts as a neutralizer in food use, acidic, preharvest herbicide products. The Dow AgroSciences, LLC, has submitted a petition to EPA under the Federal Food, Drug, and Cosmetic Act (FFDCA), requesting establishment of an......

  13. Methionine-choline deprivation alters liver and brain acetylcholinesterase activity in C57BL6 mice.

    PubMed

    Vučević, Danijela B; Cerović, Ivana B; Mladenović, Dušan R; Vesković, Milena N; Stevanović, Ivana; Jorgačević, Bojan Z; Ješić Vukićević, Rada; Radosavljević, Tatjana S

    2016-07-01

    Choline and methionine are precursors of acetylcholine, whose hydrolysis is catalyzed by acetylcholinesterase (AChE). Considering the possibility of their common deficiency, we investigated the influence of methionine-choline deprivation on AChE activity in liver and various brain regions (hypothalamus, hippocampus, cerebral cortex and striatum) in mice fed with methionine-choline deficient (MCD) diet. Male C57BL/6 mice (n = 28) were randomly and equally divided into following groups: control group fed with standard diet for 6 weeks (C) and groups fed with MCD diet for 2 weeks (MCD2), 4 weeks (MCD4) and for 6 weeks (MCD6). After the diet, mice were sacrificied and AChE activity in liver and brain was determined spectrophotometrically. Hepatic AChE activity was higher in MCD2, MCD4 and MCD6 compared to control (p < 0.01), with most prominent increase in MCD6. AChE activity in hypothalamus was higher in MCD4 and MCD6 vs. control (p < 0.05 and p < 0.01, respectively), as well as in MCD6 compared to MCD4 (p < 0.01). In hippocampus, increase in AChE activity was shown in MCD6 compared to control (p < 0.01). In cortex and striatum, increase in AChE activity was noted in MCD6 compared to control (p < 0.05). Our findings indicate the increase of hepatic and brain AChE activity in mice caused by methionine-choline deprivation. PMID:27174897

  14. The formation of choline O-sulphate by Pseudomonas C12B and other Pseudomonas species

    PubMed Central

    Fitzgerald, John W.

    1973-01-01

    Pseudomonas C12B and other Pseudomonas species released larger amounts of a 35S-labelled metabolite into the medium when cultured on growth-limiting concentrations of Na2SO4 as opposed to growth in SO42−-sufficient media. The metabolite was found at all stages of the culture cycle of Pseudomonas C12B and maximum quantities occurred in stationary-phase culture supernatants. The metabolite was not detected when the bacterium was cultured on growth-limiting concentrations of potassium phosphate. The amount of the metabolite present in the medium greatly exceeded that which could be extracted from intact cells and, except for choline chloride, it was independent of the carbon source used for growth. If choline chloride was present in high concentration, then larger amounts of the metabolite were found in the culture medium. The metabolite was not detected extracellularly or intracellularly when the bacterium was grown in SO42−-deficient media containing 5mm-l-cysteine. The same metabolite was also synthesized in vitro only when Pseudomonas C12B extracts were incubated with choline chloride, ATP, MgCl2 and Na235SO4. The metabolite-forming system was not subject to repression by Na2SO4 and was completely inhibited by 0.5mm-l-cysteine and activated by Na2SO4 (up to 1.0mm). The metabolite was identified as choline O-sulphate by electrophoresis, chromatography and isotope-dilution analysis. Another 35S-labelled metabolite was also detected in culture supernatants, but was not identified. PMID:4590202

  15. Direct Inhibition of Choline Kinase by a Near-Infrared Fluorescent Carbocyanine

    PubMed Central

    Arlauckas, Sean P.; Popov, Anatoliy V.; Delikatny, Edward J.

    2014-01-01

    Choline kinase alpha (ChoK) expression is increasingly being recognized as an important indicator of breast cancer prognosis, however previous efforts to non-invasively measure ChoK status have been complicated by the spectral limitations of in vivo magnetic resonance spectroscopy (MRS) and the complex network of enzymes involved in choline metabolism. The most effective ChoK inhibitors are symmetric and contain quaternary ammonium groups within heterocyclic head groups connected by an aliphatic spacer. Characterization of these bis-pyridinium and bis-quinolinium compounds has led to Phase I clinical trials to assess small molecule inhibitors of ChoK for solid tumor treatment. We report the development of a novel carbocyanine dye, JAS239, whose bis-indolium structure conforms to the parameters established for ChoK specificity and whose spacer length confers fluorescence in the near-infrared window. Fluorimetry and confocal microscopy were used to demonstrate that JAS239 rapidly enters breast cancer cells independent of the choline transporters, with accumulation in the cytosolic space where ChoK is active. Radio-tracing and 1H MRS techniques were used to determine that JAS239 binds and competitively inhibits ChoK intracellularly preventing choline phosphorylation while inducing cell death in breast cancer cell lines with similar efficacy to known ChoK inhibitors. Fluorescent molecules that report on ChoK status have potential use as companion diagnostics for non-invasive breast tumor staging, since NIR fluorescence allows for detection of real time probe accumulation in vivo. Furthermore, their ability as novel ChoK inhibitors may prove effective against aggressive, therapy-resistant tumors. PMID:25028471

  16. Computer-assisted nonlinear regression analysis of the multicomponent glucose uptake kinetics of Saccharomyces cerevisiae.

    PubMed Central

    Coons, D M; Boulton, R B; Bisson, L F

    1995-01-01

    The kinetics of glucose uptake in Saccharomyces cerevisiae are complex. An Eadie-Hofstee (rate of uptake versus rate of uptake over substrate concentration) plot of glucose uptake shows a nonlinear form typical of a multicomponent system. The nature of the constituent components is a subject of debate. It has recently been suggested that this nonlinearity is due to either a single saturable component together with free diffusion of glucose or a single constitutive component with a variable Km, rather than the action of multiple hexose transporters. Genetic data support the existence of a family of differentially regulated glucose transporters, encoded by the HXT genes. In this work, kinetic expressions and nonlinear regression analysis, based on an improved zero trans-influx assay, were used to address the nature of the components of the transport system. The results indicate that neither one component with free diffusion nor a single permease with a variable Km can explain the observed uptake rates. Results of uptake experiments, including the use of putative alternative substrates as inhibitory compounds, support the model derived from genetic analyses of a multicomponent system with at least two components, one a high-affinity carrier and the other a low-affinity carrier. This approach was extended to characterize the activity of the SNF3 protein and identify its role in the depression of high-affinity uptake. The kinetic data support a role of SNF3 as a regulatory protein that may not itself be a transporter. PMID:7768825

  17. Self-aggregation of sodium dodecyl sulfate within (choline chloride + urea) deep eutectic solvent.

    PubMed

    Pal, Mahi; Rai, Rewa; Yadav, Anita; Khanna, Rajesh; Baker, Gary A; Pandey, Siddharth

    2014-11-11

    Deep eutectic solvents (DESs) have shown tremendous promise as green solvents with low toxicity and cost. Understanding molecular aggregation processes within DESs will not only enhance the application potential of these solvents but also help alleviate some of the limitations associated with them. Among DESs, those comprising choline chloride and appropriate hydrogen-bond donors are inexpensive and easy to prepare. On the basis of fluorescence probe, electrical conductivity, and surface tension experiments, we present the first clear lines of evidence for self-aggregation of an anionic surfactant within a DES containing a small fraction of water. Namely, well-defined assemblies of sodium dodecyl sulfate (SDS) apparently form in the archetype DES Reline comprising a 1:2 molar mixture of choline chloride and urea. Significant enhancement in the solubility of organic solvents that are otherwise not miscible in choline chloride-based DESs is achieved within Reline in the presence of SDS. The remarkably improved solubility of cyclohexane within SDS-added Reline is attributed to the presence of spontaneously formed cyclohexane-in-Reline microemulsions by SDS under ambient conditions. Surface tension, dynamic light scattering (DLS), small-angle X-ray scattering (SAXS), density, and dynamic viscosity measurements along with responses from the fluorescence dipolarity and microfluidity probes of pyrene and 1,3-bis(1-pyrenyl)propane are employed to characterize these aggregates. Such water-free oil-in-DES microemulsions are appropriately sized to be considered as a new type of nanoreactor. PMID:25314953

  18. Effect of choline magnesium trisalicylate on prostacyclin production by isolated vascular tissue of the rat.

    PubMed

    Levy, J V

    1983-01-15

    Choline Magnesium Trisalicylate (Trilisate), in therapeutic concentrations of 5, 10, 15 and 30 mg/100 ml, did not significantly affect production of prostacyclin-like (PGI2) substance by rat aortic tissue in vitro. The ED50 for inhibition of aorta PGI2-like substance production by Trilisate was 1,200 mg/100 ml. This is approximately 40 times the maximum therapeutic blood concentration achieved in humans. Choline or Magnesium salicylate produced slight but insignificant inhibition of PGI2-like substance production by rat aortic tissue in vitro. The ED50 for ibuprofen (Motrin) for inhibition of PGI2-like production of rat aortic rings was 0.65-0.92 mg/100 ml. Injection of Choline Magnesium Trisalicylate into rats (124, 250, 500 mg/kg I.P.) did not affect the normal production of PGI2-like substance of aortic tissue obtained one hour after in vivo treatment. These results suggest this anti-inflammatory salicylate does not adversely affect PGI2-like production by blood vessels, in concentrations associated with therapeutic effects in man. PMID:6342204

  19. Organization of mixed dimethyldioctadecylammonium and choline modifiers on the surface of synthetic hectorite.

    PubMed

    Andriani, Yosephine; Jack, Kevin S; Gilbert, Elliot P; Edwards, Grant A; Schiller, Tara L; Strounina, Ekaterina; Osman, Azlin F; Martin, Darren J

    2013-11-01

    Understanding the nature of mixed surfactant self-assembly on the surface of organoclays is an important step toward optimizing their performance in polymer nanocomposites and for other potential applications, where selective surface interactions are crucial. In segmented thermoplastic polyurethane nanocomposite systems, dual-modified organoclays have shown significantly better performance compared to their single-modified counterparts. Until now, we had not fully characterized the physical chemistry of these dual-modified layered silicates, but had hypothesized that the enhanced composite performance arises due to some degree of nanoscale phase separation on the nanofiller surface, which enables enhanced compatibilization and more specific and inclusive interactions with the nanoscale hard and soft domains in these thermoplastic elastomers. This work examines the organization of quaternary alkyl ammonium compounds on the surface of Lucentite SWN using X-ray diffraction (XRD), thermogravimetric analysis (TGA), attenuated total reflectance Fourier-transfer infrared (ATR FT-IR), (13)C cross-polarization (CP)/magic angle spinning (MAS) nuclear magnetic resonance (NMR), and small-angle neutron scattering (SANS). When used in combination with choline, dimethyldioctadecylammonium (DMDO) was observed to self-assemble into discontinuous hydrophobic domains. The inner part of these hydrophobic domains was essentially unaffected by the choline (CC); however, surfactant intermixing was observed either at the periphery or throughout the choline-rich phase surrounding those domains. PMID:23978291

  20. Functional characterization of choline monooxygenase, an enzyme for betaine synthesis in plants.

    PubMed

    Hibino, Takashi; Waditee, Rungaroon; Araki, Etsuko; Ishikawa, Hiroshi; Aoki, Kenji; Tanaka, Yoshito; Takabe, Teruhiro

    2002-11-01

    In plants, the first step in betaine synthesis was shown to be catalyzed by a novel Rieske-type iron-sulfur enzyme, choline monooxygenase (CMO). Although CMO so far has been found only in Chenopodiaceae and Amaranthaceae, the recent genome sequence suggests the presence of a CMO-like gene in Arabidopsis, a betaine non-accumulating plant. Here, we examined the functional properties of CMO expressed in Escherichia coli, cyanobacterium, and Arabidopsis thaliana. We found that E. coli cells in which choline dehydrogenase (CDH) was replaced with spinach CMO accumulate betaine and complement the salt-sensitive phenotype of the CDH-deleted E. coli mutant. Changes of Cys-181 in spinach CMO to Ser, Thr, and Ala and His-287 to Gly, Val, and Ala abolished the accumulation of betaine. The Arabidopsis CMO-like gene was transcribed in Arabidopsis, but its protein was not detected. When the Arabidopsis CMO-like gene was expressed in E. coli, the protein was detected but was found not to promote betaine sysnthesis. Overexpression of spinach CMO in E. coli, Synechococcus sp. PCC7942, and Arabidopsis conferred resistance to abiotic stress. These facts clearly indicate that CMO, but not the CMO-like protein, could oxidize choline and that Cys-181 and His-287 are involved in the binding of Fe-S cluster and Fe, respectively. PMID:12192001

  1. Protein Complex Purification by Affinity Capture.

    PubMed

    LaCava, John; Fernandez-Martinez, Javier; Hakhverdyan, Zhanna; Rout, Michael P

    2016-01-01

    Affinity capture has become a powerful technique for consistently purifying endogenous protein complexes, facilitating biochemical and biophysical assays on otherwise inaccessible biological assemblies, and enabling broader interactomic exploration. For this procedure, cells are broken and their contents separated and extracted into a solvent, permitting access to target macromolecular complexes thus released in solution. The complexes are specifically enriched from the extract onto a solid medium coupled with an affinity reagent-usually an antibody-that recognizes the target either directly or through an appended affinity tag, allowing subsequent characterization of the complex. Here, we discuss approaches and considerations for purifying endogenous yeast protein complexes by affinity capture. PMID:27371601

  2. A Novel Vertex Affinity for Community Detection

    SciTech Connect

    Yoo, Andy; Sanders, Geoffrey; Henson, Van; Vassilevski, Panayot

    2015-10-05

    We propose a novel vertex affinity measure in this paper. The new vertex affinity quantifies the proximity between two vertices in terms of their clustering strength and is ideal for such graph analytics applications as community detection. We also developed a framework that combines simple graph searches and resistance circuit formulas to compute the vertex affinity efficiently. We study the properties of the new affinity measure empirically in comparison to those of other popular vertex proximity metrics. Our results show that the existing metrics are ill-suited for community detection due to their lack of fundamental properties that are essential for correctly capturing inter- and intra-cluster vertex proximity.

  3. Structural determinants of sigma receptor affinity

    SciTech Connect

    Largent, B.L.; Wikstroem, H.G.; Gundlach, A.L.; Snyder, S.H.

    1987-12-01

    The structural determinants of sigma receptor affinity have been evaluated by examining a wide range of compounds related to opioids, neuroleptics, and phenylpiperidine dopaminergic structures for affinity at sigma receptor-binding sites labeled with (+)-(/sup 3/H)3-PPP. Among opioid compounds, requirements for sigma receptor affinity differ strikingly from the determinants of affinity for conventional opiate receptors. Sigma sites display reverse stereoselectivity to classical opiate receptors. Multi-ringed opiate-related compounds such as morphine and naloxone have negligible affinity for sigma sites, with the highest sigma receptor affinity apparent for benzomorphans which lack the C ring of opioids. Highest affinity among opioids and other compounds occurs with more lipophilic N-substituents. This feature is particularly striking among the 3-PPP derivatives as well as the opioids. The butyrophenone haloperidol is the most potent drug at sigma receptors we have detected. Among the series of butyrophenones, receptor affinity is primarily associated with the 4-phenylpiperidine moiety. Conformational calculations for various compounds indicate a fairly wide range of tolerance for distances between the aromatic ring and the amine nitrogen, which may account for the potency at sigma receptors of structures of considerable diversity. Among the wide range of structures that bind to sigma receptor-binding sites, the common pharmacophore associated with high receptor affinity is a phenylpiperidine with a lipophilic N-substituent.

  4. Compact noncontraction semigroups of affine operators

    NASA Astrophysics Data System (ADS)

    Voynov, A. S.; Protasov, V. Yu

    2015-07-01

    We analyze compact multiplicative semigroups of affine operators acting in a finite-dimensional space. The main result states that every such semigroup is either contracting, that is, contains elements of arbitrarily small operator norm, or all its operators share a common invariant affine subspace on which this semigroup is contracting. The proof uses functional difference equations with contraction of the argument. We look at applications to self-affine partitions of convex sets, the investigation of finite affine semigroups and the proof of a criterion of primitivity for nonnegative matrix families. Bibliography: 32 titles.

  5. Effects of ethanolamine and choline on thiotepa cellular accumulation and cytotoxicity in L1210 cells

    SciTech Connect

    Egorin, M.J.; Snyder, S.W.; Wietharn, B.E. )

    1990-07-15

    The amino alcohols, ethanolamine and choline, were studied for their effects on (a) L1210 cell growth, (b) N,N{prime},N{double prime}-triethylenetheiphosphoramide (thiotepa)-induced growth inhibition of L1210 cells, and (c) 14C accumulation by L1210 cells incubated with (14C)thiotepa. Ethanolamine, at concentrations up to 300 microM, had no effect on L1210 cell growth but, at concentrations greater than 300 microM, produced a dose-dependent reduction in cell growth. Choline, at concentrations up to 20 mM, had no effect on L1210 cell growth. Neither ethanolamine, at 250 microM, nor choline, at 10 mM, altered the ability of thiotepa to reduce L1210 cell growth. Neither ethanolamine, at 250 microM, nor choline, at 10 mM, affected the rapid phase of 14C accumulation by L1210 cells incubated with (14C)thiotepa. The slow phase of 14C accumulation by L1210 cells incubated with 5 microM (14C)thiotepa, a process which is 80-85% due to production of (14C)phosphatidylethanolamine, was not affected by 250 microM choline. In contrast, ethanolamine produced a dose-dependent reduction in this slow rate of 14C accumulation. The reduction in the slow rate of 14C accumulation produced by ethanolamine was due almost entirely to a decrease in the accumulation of nonexchangeable 14C. Kinetic analysis of the inhibition of 14C accumulation produced by 25, 100, and 250 microM ethanolamine was compatible with competitive inhibition. Thin layer chromatography of cell extracts showed that the ability of ethanolamine to reduce 14C accumulation by L1210 cells incubated with (14C)thiotepa was due solely to reduction in production of (14C)phosphatidylethanolamine. These results are all compatible with and predicted by our previously described scheme wherein thiotepa enters cells by simple diffusion and serves as a prodrug for aziridine.

  6. Structure of classical affine and classical affine fractional W-algebras

    SciTech Connect

    Suh, Uhi Rinn

    2015-01-15

    We introduce a classical BRST complex (See Definition 3.2.) and show that one can construct a classical affine W-algebra via the complex. This definition clarifies that classical affine W-algebras can be considered as quasi-classical limits of quantum affine W-algebras. We also give a definition of a classical affine fractional W-algebra as a Poisson vertex algebra. As in the classical affine case, a classical affine fractional W-algebra has two compatible λ-brackets and is isomorphic to an algebra of differential polynomials as a differential algebra. When a classical affine fractional W-algebra is associated to a minimal nilpotent, we describe explicit forms of free generators and compute λ-brackets between them. Provided some assumptions on a classical affine fractional W-algebra, we find an infinite sequence of integrable systems related to the algebra, using the generalized Drinfel’d and Sokolov reduction.

  7. Scaling analysis of affinity propagation.

    PubMed

    Furtlehner, Cyril; Sebag, Michèle; Zhang, Xiangliang

    2010-06-01

    We analyze and exploit some scaling properties of the affinity propagation (AP) clustering algorithm proposed by Frey and Dueck [Science 315, 972 (2007)]. Following a divide and conquer strategy we setup an exact renormalization-based approach to address the question of clustering consistency, in particular, how many cluster are present in a given data set. We first observe that the divide and conquer strategy, used on a large data set hierarchically reduces the complexity O(N2) to O(N((h+2)/(h+1))) , for a data set of size N and a depth h of the hierarchical strategy. For a data set embedded in a d -dimensional space, we show that this is obtained without notably damaging the precision except in dimension d=2 . In fact, for d larger than 2 the relative loss in precision scales such as N((2-d)/(h+1)d). Finally, under some conditions we observe that there is a value s* of the penalty coefficient, a free parameter used to fix the number of clusters, which separates a fragmentation phase (for ss*) of the underlying hidden cluster structure. At this precise point holds a self-similarity property which can be exploited by the hierarchical strategy to actually locate its position, as a result of an exact decimation procedure. From this observation, a strategy based on AP can be defined to find out how many clusters are present in a given data set. PMID:20866473

  8. Saturable Hepatic Extraction of Gemcitabine Involves Biphasic Uptake Mediated by Nucleoside Transporters Equilibrative Nucleoside Transporter 1 and 2.

    PubMed

    Shimada, Takuya; Nakanishi, Takeo; Tajima, Hidehiro; Yamazaki, Maiko; Yokono, Rina; Takabayashi, Makiko; Shimada, Tsutomu; Sawamoto, Kazuki; Miyamoto, Ken-Ichi; Kitagawa, Hirohisa; Ohta, Tetsuo; Tamai, Ikumi; Sai, Yoshimichi

    2015-09-01

    Hepatic arterial infusion (HAI) chemotherapy with gemcitabine (GEM) is expected to be more effective and safer method to treat hepatic metastasis of pancreatic cancer compared with intravenous administration, because it affords higher tumor exposure with lower systemic exposure. Thus, a key issue for dose selection is the saturability of hepatic uptake of GEM. Therefore, we investigated GEM uptake in rat and human isolated hepatocytes. Hepatic GEM uptake involved high- and low-affinity saturable components with Km values of micromolar and millimolar order, respectively. The uptake was inhibited concentration dependently by S-(4-nitrobenzyl)-6-thioinosine (NBMPR) and was sodium-ion-independent, suggesting a contribution of equilibrative nucleoside transporters (ENTs). The concentration dependence of uptake in the presence of 0.1 μM NBMPR showed a single low-affinity binding site. Therefore, the high- and low-affinity sites correspond to ENT1 and ENT2, respectively. Our results indicate hepatic extraction of GEM is predominantly mediated by the low-affinity site (hENT2), and at clinically relevant hepatic concentrations of GEM, hENT2-mediated uptake would not be completely saturated. This is critical for HAI, because saturation of hepatic uptake would result in a marked increase of GEM concentration in the peripheral circulation, abrogating the advantage of HAI over intravenous administration in terms of severe adverse events. PMID:26037416

  9. Methods for Improving Aptamer Binding Affinity.

    PubMed

    Hasegawa, Hijiri; Savory, Nasa; Abe, Koichi; Ikebukuro, Kazunori

    2016-01-01

    Aptamers are single stranded oligonucleotides that bind a wide range of biological targets. Although aptamers can be isolated from pools of random sequence oligonucleotides using affinity-based selection, aptamers with high affinities are not always obtained. Therefore, further refinement of aptamers is required to achieve desired binding affinities. The optimization of primary sequences and stabilization of aptamer conformations are the main approaches to refining the binding properties of aptamers. In particular, sequence optimization using combined in silico sequence recombinations and in vitro functional evaluations is effective for the improvement of binding affinities, however, the binding affinities of aptamers are limited by the low hydrophobicity of nucleic acids. Accordingly, introduction of hydrophobic moieties into aptamers expands the diversity of interactions between aptamers and targets. Moreover, construction of multivalent aptamers by connecting aptamers that recognize distinct epitopes is an attractive approach to substantial increases in binding affinity. In addition, binding affinities can be tuned by optimizing the scaffolds of multivalent constructs. In this review, we summarize the various techniques for improving the binding affinities of aptamers. PMID:27043498

  10. Affine root systems and dual numbers

    NASA Astrophysics Data System (ADS)

    Kostyakov, I. V.; Gromov, N. A.; Kuratov, V. V.

    The root systems in Carroll spaces with degenerate metric are defined. It is shown that their Cartan matrices and reflection groups are affine. Due to the geometric consideration the root system structure of affine algebras is determined by a sufficiently simple algorithm.

  11. Loop realizations of quantum affine algebras

    SciTech Connect

    Cautis, Sabin; Licata, Anthony

    2012-12-15

    We give a simplified description of quantum affine algebras in their loop presentation. This description is related to Drinfeld's new realization via halves of vertex operators. We also define an idempotent version of the quantum affine algebra which is suitable for categorification.

  12. Intestinal Microbiota Composition Modulates Choline Bioavailability from Diet and Accumulation of the Proatherogenic Metabolite Trimethylamine-N-Oxide

    PubMed Central

    Romano, Kymberleigh A.; Vivas, Eugenio I.

    2015-01-01

    ABSTRACT Choline is a water-soluble nutrient essential for human life. Gut microbial metabolism of choline results in the production of trimethylamine (TMA), which upon absorption by the host is converted in the liver to trimethylamine-N-oxide (TMAO). Recent studies revealed that TMAO exacerbates atherosclerosis in mice and positively correlates with the severity of this disease in humans. However, which microbes contribute to TMA production in the human gut, the extent to which host factors (e.g., genotype) and diet affect TMA production and colonization of these microbes, and the effects TMA-producing microbes have on the bioavailability of dietary choline remain largely unknown. We screened a collection of 79 sequenced human intestinal isolates encompassing the major phyla found in the human gut and identified nine strains capable of producing TMA from choline in vitro. Gnotobiotic mouse studies showed that TMAO accumulates in the serum of animals colonized with TMA-producing species, but not in the serum of animals colonized with intestinal isolates that do not generate TMA from choline in vitro. Remarkably, low levels of colonization by TMA-producing bacteria significantly reduced choline levels available to the host. This effect was more pronounced as the abundance of TMA-producing bacteria increased. Our findings provide a framework for designing strategies aimed at changing the representation or activity of TMA-producing bacteria in the human gut and suggest that the TMA-producing status of the gut microbiota should be considered when making recommendations about choline intake requirements for humans. PMID:25784704

  13. CDP-choline attenuates scopolamine induced disruption of prepulse inhibition in rats: involvement of central nicotinic mechanism.

    PubMed

    Uslu, Gulsah; Savci, Vahide; Buyukuysal, Levent R; Goktalay, Gokhan

    2014-05-21

    It has been shown that cholinergic system plays an important role in schizophrenia-associated cognitive deficits, therefore cholinergic drugs are novel targets for the treatment of cognitive deficits seen in schizophrenia. We aimed to test the effects of CDP-choline on sensorimotor gating functioning, which is an important function for the integration of sensory and cognitive information processing and the execution of appropriate motor responses. In this study, prepulse inhibition (PPI) of the acoustic startle reflex was used to test the sensorimotor gating functioning, and the effects of CDP-choline on scopolamine induced PPI disruption were evaluated in rats. Furthermore, the contribution of the cholinergic mechanism in these effects was determined. CDP-choline (75, 250, 500mg/kg) by itself had no effect on the PPI in naïve animals. Scopolamine (0.4mg/kg; s.c.) significantly decreased the PPI levels and intraperitoneal administration of CDP-choline (250mg/kg) attenuated the effects of scopolamine. A non-specific nicotinic receptor antagonist, mecamylamine and an alpha 7 nicotinic receptor (α7-nAChR) antagonist, methyllycaconitine were used to investigate the mechanism underlying the effects of CDP-choline. Mecamylamine (3mg/kg; s.c.), and methyllycaconitine (10μg; i.c.v.) completely blocked the reversal effects of CDP-choline on scopolamine induced disruption of PPI. These results demonstrate that exogenous administration of CDP-choline attenuates scopolamine induced PPI disruption and show that the activation of central α7-nAChR may play a critical role in this effect. PMID:24708927

  14. Improving image segmentation by learning region affinities

    SciTech Connect

    Prasad, Lakshman; Yang, Xingwei; Latecki, Longin J

    2010-11-03

    We utilize the context information of other regions in hierarchical image segmentation to learn new regions affinities. It is well known that a single choice of quantization of an image space is highly unlikely to be a common optimal quantization level for all categories. Each level of quantization has its own benefits. Therefore, we utilize the hierarchical information among different quantizations as well as spatial proximity of their regions. The proposed affinity learning takes into account higher order relations among image regions, both local and long range relations, making it robust to instabilities and errors of the original, pairwise region affinities. Once the learnt affinities are obtained, we use a standard image segmentation algorithm to get the final segmentation. Moreover, the learnt affinities can be naturally unutilized in interactive segmentation. Experimental results on Berkeley Segmentation Dataset and MSRC Object Recognition Dataset are comparable and in some aspects better than the state-of-art methods.

  15. Low-affinity transport of FITC-albumin in alveolar type II epithelial cell line RLE-6TN.

    PubMed

    Tagawa, Maki; Yumoto, Ryoko; Oda, Keisuke; Nagai, Junya; Takano, Mikihisa

    2008-01-01

    FITC-albumin uptake by cultured alveolar type II epithelial cells, RLE-6TN, is mediated by high- and low-affinity transport systems. In this study, characteristics of the low-affinity transport system were evaluated. The uptake of FITC-albumin was time and temperature dependent and was inhibited by metabolic inhibitors and bafilomycin A1. Confocal laser scanning microscopic analysis showed punctate localization of the fluorescence in the cells, which was partly localized in lysosomes. FITC-albumin taken up by the cells gradually degraded over time, as shown by fluoroimage analyzer after SDS-PAGE. The uptake of FITC-albumin by RLE-6TN cells was not inhibited by caveolae-mediated endocytosis inhibitors such as nystatin, but was inhibited by clathrin-mediated endocytosis inhibitors such as phenylarsine oxide. The uptake was also inhibited by potassium depletion and hypertonicity, conditions known to inhibit clathrin-mediated endocytosis. In addition, macropinocytosis inhibitors such as 5-(N-ethyl-N-isopropyl) amiloride inhibited the uptake. These results indicate that the low-affinity transport of FITC-albumin in RLE-6TN cells is at least in part mediated by clathrin-mediated endocytosis, but not by caveolae-mediated endocytosis. Possible involvement of macropinocytosis was also suggested. PMID:18974609

  16. Acquisition with (11)C-choline and (18)F-fluorocholine PET/CT for patients with biochemical recurrence of prostate cancer: a systematic review and meta-analysis.

    PubMed

    von Eyben, Finn E; Kairemo, Kalevi

    2016-07-01

    The objective of the systematic review and meta-analysis was to evaluate whether the choice between two radiotracers, (11)C-choline ((11)C-cho) and (18)F-fluorocholine ((18)F-FCH) for PET/CT, and different acquisition protocols contributed to detect metastases for patients with biochemical recurrence of prostate cancer after radical prostatectomy or radiotherapy. We searched in January 2016 in Pubmed and Embase for articles that had used radiolabeled choline PET/CT in restaging. The meta-analysis evaluated technical and clinical aspects. Across 18 articles 1 219 of 2 213 patients (54.9 %) had a positive radiolabeled PET/CT image. Mean of the mean/median restaging PSA levels was 3.6 ± 2.7 ng/mL (range 0.5-10.7 ng/mL). Six articles with (11)C-cho PET/CT had a radiation activity of 561 ± 122 MBq and it was 293 ± 47 MBq in 12 articles with (18)F-FCH PET/CT. The difference was significant (P = 0.007, t test). Uptake time was 5 min in articles with (11)C-cho PET/CT and it was 29 ± 24 min in articles with (18)F-FCH PET/CT. The difference was significant (P = 0.02, t test). Thereby the detection rates of metastatic sites in articles with (11)C-cho (30 ± 5 %) and (18)F-FCH (39 ± 5 %) did not differ significantly (P = 0.26, t test). In linear regression analyses of the articles, the radiation activity of (11)C-cho and (18)F-FCH was not significantly associated with the detection rate of metastatic sites (P = 0.75 and P = 0.60). Restaging with radiolabeled choline PET/CT detected metastatic sites for patients with biochemical recurrence and PSA levels of 1-10 ng/mL at clinically relevant level. The choice between the two choline radiotracers and different acquisition protocols had no significant impact on detection. PMID:27173771

  17. Peptide uptake by astroglia-rich brain cultures.

    PubMed

    Schulz, M; Hamprecht, B; Kleinkauf, H; Bauer, K

    1987-09-01

    Uptake of carnosine has been investigated in astroglia-rich primary cultures derived from brains of newborn mice. It could be demonstrated that carnosine is not degraded by these cells but rapidly taken up in an energy- and sodium-dependent process. Uptake and release of carnosine by these cells were found to be mediated by a saturable, high-affinity transport system with apparent kinetic constants of Km = 50 microM and Vmax = 22.7 nmol X h-1 X mg protein-1. Uptake of carnosine is strongly inhibited by other dipeptides as well as by various oligopeptides, e.g., Leu-enkephalin. However, uptake of the radiolabeled tripeptide D-Ala-L-Ala-L-Ala was not observed. Radiolabeled Leu-enkephalin also did not accumulate intracellularly, even if degradation of the peptide was prevented by use of peptidase inhibitors. These results suggest that uptake of carnosine is catalyzed by a dipeptide-specific transport system with broad substrate specificity. With neuronal cells in primary culture, uptake of carnosine or other peptides was not observed. PMID:3612123

  18. Probable free radical effects on rat liver nuclei during early hepatocarcinogenesis with a choline-devoid low methionine diet.

    PubMed

    Rushmore, T H; Ghazarian, D M; Subrahmanyan, V; Farber, E; Ghoshal, A K

    1987-12-15

    Fischer-344 rats fed a choline-devoid diet show lipid peroxidation in the liver nuclei, beginning at 1 day, reaching a peak at 3 days, and subsequently declining by 35 days. Lipid peroxidation in the mitochondria was seen first at 3 days, increased to a maximum at 28 days, and decreased after 35 days to undetectable values at 49 days. Lipid peroxidation was found in both nuclear and mitochondrial fractions both before and after stripping of their outer membranes. No microsomal lipid peroxidation could be detected at any time up to 63 days. The animals fed the same diet supplemented with choline showed no lipid peroxidation in any liver fraction. Animals given CCl4 showed the expected lipid peroxidation in the microsomes but not in the nuclear fraction. The administration of the free radical trapping agent, N-tert-butyl-alpha-phenylnitrone, prevented completely or almost so, microsomal lipid peroxidation induced by CCl4 and nuclear lipid peroxidation in the animals fed the choline-devoid, low methionine diet. The genesis of free radicals in the livers of rats fed a choline-devoid diet is considered as a likely hypothesis for the observed lipid peroxidation. The lipid peroxidation in turn is considered to be closely related to the induction of liver cell death and to the production of alterations in DNA. The DNA alterations coupled with regenerative liver cell proliferation suggest an attractive hypothesis for the initiation of hepatocarcinogenesis in rats fed a choline-devoid diet. PMID:3677103

  19. Structural studies on choline-carboxylate bio-ionic liquids by x-ray scattering and molecular dynamics

    NASA Astrophysics Data System (ADS)

    Tanzi, Luana; Ramondo, Fabio; Caminiti, Ruggero; Campetella, Marco; Di Luca, Andrea; Gontrani, Lorenzo

    2015-09-01

    We report a X-ray diffraction and molecular dynamics study on three choline-based bio-ionic liquids, choline formate, [Ch] [For], choline propanoate, [Ch][Pro], and choline butanoate, [Ch][But]. For the first time, this class of ionic liquids has been investigated by X-ray diffraction. Experimental and theoretical structure factors have been compared for each term of the series. Local structural organization has been obtained from ab initio calculations through static models of isolated ion pairs and dynamic simulations of small portions of liquids through twelve, ten, and nine ion pairs for [Ch][For], [Ch][Pro], and [Ch][But], respectively. All the theoretical models indicate that cations and anions are connected by strong hydrogen bonding and form stable ion pairs in the liquid that are reminiscent of the static ab initio ion pairs. Different structural aspects may affect the radial distribution function, like the local structure of ion pairs and the conformation of choline. When small portions of liquids have been simulated by dynamic quantum chemical methods, some key structural features of the X-ray radial distribution function were well reproduced whereas the classical force fields here applied did not entirely reproduce all the observed structural features.

  20. Structural studies on choline-carboxylate bio-ionic liquids by x-ray scattering and molecular dynamics

    SciTech Connect

    Tanzi, Luana; Ramondo, Fabio; Caminiti, Ruggero; Campetella, Marco; Di Luca, Andrea; Gontrani, Lorenzo

    2015-09-21

    We report a X-ray diffraction and molecular dynamics study on three choline-based bio-ionic liquids, choline formate, [Ch] [For], choline propanoate, [Ch][Pro], and choline butanoate, [Ch][But]. For the first time, this class of ionic liquids has been investigated by X-ray diffraction. Experimental and theoretical structure factors have been compared for each term of the series. Local structural organization has been obtained from ab initio calculations through static models of isolated ion pairs and dynamic simulations of small portions of liquids through twelve, ten, and nine ion pairs for [Ch][For], [Ch][Pro], and [Ch][But], respectively. All the theoretical models indicate that cations and anions are connected by strong hydrogen bonding and form stable ion pairs in the liquid that are reminiscent of the static ab initio ion pairs. Different structural aspects may affect the radial distribution function, like the local structure of ion pairs and the conformation of choline. When small portions of liquids have been simulated by dynamic quantum chemical methods, some key structural features of the X-ray radial distribution function were well reproduced whereas the classical force fields here applied did not entirely reproduce all the observed structural features.

  1. Adequate Intake levels of choline are sufficient for preventing elevations in serum markers of liver dysfunction in Mexican American men but are not optimal for minimizing plasma total homocysteine increases after a methionine load2

    PubMed Central

    Veenema, Kristin; Solis, Claudia; Li, Rui; Wang, Wei; Maletz, Charles V; Abratte, Christian M; Caudill, Marie A

    2009-01-01

    Background An adequate intake of 550 mg choline/d was established for the prevention of liver dysfunction in men, as assessed by measuring serum alanine aminotransferase concentrations. Objective This controlled feeding study investigated the influence of choline intakes ranging from 300 to 2200 mg/d on biomarkers of choline status. The effect of the methylenetetrahydrofolate reductase (MTHFR) C677T genotype on choline status was also examined. Design Mexican American men (n = 60) with different MTHFR C677T genotypes (29 677TT, 31 677CC) consumed a diet providing 300 mg choline/d plus supplemental choline intakes of 0, 250, 800, or 1900 mg/d for total choline intakes of 300, 550, 1100, or 2200 mg/d, respectively, for 12 wk; 400 μg/d as dietary folate equivalents and 173 mg betaine/d were consumed throughout the study. Results Choline intake affected the response of plasma free choline and betaine (time × choline, P < 0.001); the highest concentrations were observed in the 2200 mg/d group. Phosphatidylcholine (P = 0.026) and total cholesterol (P = 0.002) were also influenced by choline intake; diminished concentrations were observed in the 300 mg/d group. Phosphatidylcholine was modified by MTHFR genotype (P = 0.035; 677TT < 677CC). After a methionine load (100 mg/kg body wt), choline intakes of 1100 and 2200 mg/d attenuated (P = 0.016) the rise in plasma homocysteine, as did the MTHFR 677TT genotype (P < 0.001). Serum alanine aminotransferase was not influenced by the choline intakes administered in this study. Conclusions These data suggest that 550 mg choline/d is sufficient for preventing elevations in serum markers of liver dysfunction in this population under the conditions of this study; higher intakes may be needed to optimize other endpoints. PMID:18779284

  2. Acute low-level microwave exposure and central cholinergic activity: studies on irradiation parameters

    SciTech Connect

    Lai, H.; Horita, A.; Guy, A.W.

    1988-01-01

    Sodium-dependent high-affinity choline uptake was measured in the striatum, frontal cortex, hippocampus, and hypothalamus of rats after acute exposure (45 min) to pulsed (2 microseconds, 500 pps) or continuous-wave 2,450-MHz microwaves in cylindrical waveguides or miniature anechoic chambers. In all exposure conditions, the average whole-body specific absorption rate was at 0.6 W/kg. Decrease in choline uptake was observed in the frontal cortex after microwave exposure in all of the above irradiation conditions. Regardless of the exposure system used, hippocampal choline uptake was decreased after exposure to pulsed but not continuous-wave microwaves. Striatal choline uptake was decreased after exposure to either pulsed or continuous-wave microwaves in the miniature anechoic chamber. No significant change in hypothalamic choline uptake was observed under any of the exposure conditions studied. We conclude that depending on the parameters of the radiation, microwaves can elicit specific and generalized biological effects.

  3. Affinity Proteomics in the mountains: Alpbach 2015.

    PubMed

    Taussig, Michael J

    2016-09-25

    The 2015 Alpbach Workshop on Affinity Proteomics, organised by the EU AFFINOMICS consortium, was the 7th workshop in this series. As in previous years, the focus of the event was the current state of affinity methods for proteome analysis, including complementarity with mass spectrometry, progress in recombinant binder production methods, alternatives to classical antibodies as affinity reagents, analysis of proteome targets, industry focus on biomarkers, and diagnostic and clinical applications. The combination of excellent science with Austrian mountain scenery and winter sports engender an atmosphere that makes this series of workshops exceptional. The articles in this Special Issue represent a cross-section of the presentations at the 2015 meeting. PMID:27118167

  4. Optimized Affinity Capture of Yeast Protein Complexes.

    PubMed

    LaCava, John; Fernandez-Martinez, Javier; Hakhverdyan, Zhanna; Rout, Michael P

    2016-01-01

    Here, we describe an affinity isolation protocol. It uses cryomilled yeast cell powder for producing cell extracts and antibody-conjugated paramagnetic beads for affinity capture. Guidelines for determining the optimal extraction solvent composition are provided. Captured proteins are eluted in a denaturing solvent (sodium dodecyl sulfate polyacrylamide gel electrophoresis sample buffer) for gel-based proteomic analyses. Although the procedures can be modified to use other sources of cell extract and other forms of affinity media, to date we have consistently obtained the best results with the method presented. PMID:27371596

  5. Aptamers in Affinity Separations: Stationary Separation

    NASA Astrophysics Data System (ADS)

    Ravelet, Corinne; Peyrin, Eric

    The use of DNA or RNA aptamers as tools in analytical chemistry is a very promising field of research because of their capabilities to bind specifically the target molecules with an affinity similar to that of antibodies. Notably, they appear to be of great interest as target-specific ligands for the separation and capture of various analytes in affinity chromatography and related affinity-based methods such as magnetic bead technology. In this chapter, the recent developments of these aptamer-based separation/capture approaches are addressed.

  6. Affinity purification of heme-tagged proteins.

    PubMed

    Asher, Wesley B; Bren, Kara L

    2014-01-01

    Protein affinity purification techniques are widely used for isolating pure target proteins for biochemical and structural characterization. Herein, we describe the protocol for affinity-based purification of proteins expressed in Escherichia coli that uses the coordination of a peptide tag covalently modified with heme c, known as a heme-tag, to an L-histidine immobilized Sepharose resin. This approach provides an affinity purification tag visible to the eye, facilitating tracking of the protein. In addition, we describe methods for specifically detecting heme-tagged proteins in SDS-PAGE gels using a heme-staining procedure and for quantifying the proteins using a pyridine hemochrome assay. PMID:24943311

  7. Hepatoblastoma evaluated by 18F-fluoromethyl choline PET/CT.

    PubMed

    Bieze, Matthanja; van Gulik, Thomas M; Bennink, Roelof J

    2013-02-01

    Hepatoblastoma is a rare carcinoma mostly seen in children. Neoadjuvant chemotherapy followed by resection and adjuvant chemotherapy is the optimal treatment. We present the case of an 18-year-old woman who presented with abdominal pain, nausea, bloating, and fatigue. MRI showed 3 hepatic lesions with high signal intensity on arterial phase T1-weighted images and slight washout on the late phase, suggestive for hepatocellular carcinoma. Laboratory examinations revealed plasma α-feto-protein of 114,245 μg/L. Subsequent baseline and posttreatment F-fluoromethyl choline PET/CT were performed to possibly evaluate extent of the disease and assess disease response after neoadjuvant chemotherapy. PMID:23334143

  8. Choline Acetyltransferase Activity in Striatum of Neonatal Rats Increased by Nerve Growth Factor

    NASA Astrophysics Data System (ADS)

    Mobley, William C.; Rutkowski, J. Lynn; Tennekoon, Gihan I.; Buchanan, Karen; Johnston, Michael V.

    1985-07-01

    Some neurodegenerative disorders may be caused by abnormal synthesis or utilization of trophic molecules required to support neuronal survival. A test of this hypothesis requires that trophic agents specific for the affected neurons be identified. Cholinergic neurons in the corpus striatum of neonatal rats were found to respond to intracerebroventricular administration of nerve growth factor with prominent, dose-dependent, selective increases in choline acetyltransferase activity. Cholinergic neurons in the basal forebrain also respond to nerve growth factor in this way. These actions of nerve growth factor may indicate its involvement in the normal function of forebrain cholinergic neurons as well as in neurodegenerative disorders involving such cells.

  9. In vitro behavior of human intestinal mucosa. The influence of acetyl choline on ion transport.

    PubMed Central

    Isaacs, P E; Corbett, C L; Riley, A K; Hawker, P C; Turnberg, L A

    1976-01-01

    The possibility that the autonomic nervous system may influence the function of intestinal mucosa was investigated by assessing the effect of acetyl choline on ion transport in human intestine. Isolated pieces of stripped ileal mucosa were mounted in Perspex flux-chambers and bathed in isotonic glucose Ringer's solution. Acetyl choline caused a rise in mean potential difference (8.8-12.3 mV, P less than 0.002) and short circuit current (287.7-417.2 muA-cm-2, P less than 0.01) (n = 12), observable at a concentration of 0.01 mM and maximal at 0.1 mM. This effect was enhanced by neostigmine and blocked by atropine. Isotopic flux determinations revealed a change from a small mean net Cl absorption (58) to a net Cl secretion (-4.3mueq-cm-2-h-1P less than 0.001) due predominantly to an increase in the serosal to mucosal unidirectional flux of Cl (10.63-14.35 mueq-cm-2-h-1P less than 0.05) and a smaller reduction in the mucosal to serosal flux (11.22 to 10.02 mueq-cm-2-h-1P less than 0.05). Unidirectional and net Na transport was unaffected. A similar electrical and ion transport response was observed in a single study of two pieces of jejunal mucosa. In the absence of glucose net chloride secretion was produced and again an insignificant effect on net sodium transport was noted. Acetyl choline did not provoke a sustained effect on mucosal cyclic adenine nucleotide levels although a short-lived cyclic adenine nucleotide response was seen in some tissues 20-30 s after drug addition. These studies demonstrate that acetyl choline does influence human intestinal ion transport by stimulating chloride secretion and suggest a possible mechanism by which the parasympathetic nervous system could be concerned in the control of ion transport. Images PMID:182722

  10. Value of bimodal (18)F-choline-PET/MRI and trimodal (18)F-choline-PET/MRI/TRUS for the assessment of prostate cancer recurrence after radiation therapy and radical prostatectomy.

    PubMed

    Paparo, Francesco; Piccardo, Arnoldo; Bacigalupo, Lorenzo; Romagnoli, Andrea; Piccazzo, Riccardo; Monticone, Michela; Cevasco, Luca; Campodonico, Fabio; Conzi, Giuseppe Maria; Carmignani, Giorgio; Rollandi, Gian Andrea

    2015-08-01

    Between 27% and 53% of all patients who undergo radical prostatectomy (RP) or radiation therapy (RT) as the first-line treatment of prostate cancer (PCa) develop a biochemical recurrence. Imaging plays a pivotal role in restaging by helping to distinguish between local relapse and metastatic disease (i.e., lymph-node and skeletal metastases). At present, the most promising tools for assessing PCa patients with biochemical recurrence are multiparametric magnetic resonance imaging (mpMRI) and positron emission tomography (PET)/computed tomography (CT) with radio-labeled choline derivatives. The main advantage of mpMRI is its high diagnostic accuracy in detecting local recurrence, while choline-PET/CT is able to identify lymph-node metastases when they are not suspicious on morphological imaging. The most recent advances in the field of fusion imaging have shown that multimodal co-registration, synchronized navigation, and combined interpretation are more valuable than the individual; separate assessment offered by different diagnostic techniques. The objective of the present essay was to describe the value of bimodal choline-PET/mpMRI fusion imaging and trimodal choline-PET/mpMRI/transrectal ultrasound (TRUS) in the assessment of PCa recurrence after RP and RT. Bimodal choline-PET/mpMRI fusion imaging allows morphological, functional, and metabolic information to be combined, thereby overcoming the limitations of each separate imaging modality. In addition, trimodal real-time choline-PET/mpMRI/TRUS fusion imaging may be useful for the planning and real-time guidance of biopsy procedures in order to obtain histological confirmation of the local recurrence. PMID:25579170

  11. High affinity binding of (/sup 3/H)cocaine to rat liver microsomes

    SciTech Connect

    El-Maghrabi, E.A.; Calligaro, D.O.; Eldefrawi, M.E.

    1988-01-01

    )/sup 3/H)cocaine bound reversible, with high affinity and stereospecificity to rat liver microsomes. Little binding was detected in the lysosomal, mitochondrial and nuclear fractions. The binding kinetics were slow and the kinetically calculated K/sub D/ was 2 nM. Induction of mixed function oxidases by phenobarbital did not produce significant change in (/sup 3/H)cocaine binding. On the other hand, chronic administration of cocaine reduced (/sup 3/H)cocaine binding drastically. Neither treatment affected the affinity of the liver binding protein for cocaine. Microsomes from mouse and human livers had less cocaine-binding protein and lower affinity for cocaine than those from rat liver. Binding of (/sup 3/H)cocaine to rat liver microsomes was insensitive to monovalent cations and > 10 fold less sensitive to biogenic amines than the cocaine receptor in rat striatum. However, the liver protein had higher affinity for cocaine and metabolites except for norcocaine. Amine uptake inhibitors displaced (/sup 3/H)cocaine binding to liver with a different rank order of potency than their displacement of (/sup 3/H)cocaine binding to striatum. This high affinity (/sup 3/H)cocaine binding protein in liver is not likely to be monooxygenase, but may have a role in cocaine-induced hepatotoxicity

  12. Crystal structure of the plant dual-affinity nitrate transporter NRT1.1

    NASA Astrophysics Data System (ADS)

    Sun, Ji; Bankston, John R.; Payandeh, Jian; Hinds, Thomas R.; Zagotta, William N.; Zheng, Ning

    2014-03-01

    Nitrate is a primary nutrient for plant growth, but its levels in soil can fluctuate by several orders of magnitude. Previous studies have identified Arabidopsis NRT1.1 as a dual-affinity nitrate transporter that can take up nitrate over a wide range of concentrations. The mode of action of NRT1.1 is controlled by phosphorylation of a key residue, Thr 101 however, how this post-translational modification switches the transporter between two affinity states remains unclear. Here we report the crystal structure of unphosphorylated NRT1.1, which reveals an unexpected homodimer in the inward-facing conformation. In this low-affinity state, the Thr 101 phosphorylation site is embedded in a pocket immediately adjacent to the dimer interface, linking the phosphorylation status of the transporter to its oligomeric state. Using a cell-based fluorescence resonance energy transfer assay, we show that functional NRT1.1 dimerizes in the cell membrane and that the phosphomimetic mutation of Thr 101 converts the protein into a monophasic high-affinity transporter by structurally decoupling the dimer. Together with analyses of the substrate transport tunnel, our results establish a phosphorylation-controlled dimerization switch that allows NRT1.1 to uptake nitrate with two distinct affinity modes.

  13. [The effect of locally applied Grisaldone or choline salicylate gel on bone healing after tooth extraction in animal experiments].

    PubMed

    Cendelin, E; Fröhlich, M

    1977-01-01

    Comparative histological and experimental animal studies of the effects upon bone wound healing of topically applied choline salicylate gel and Grisaldon showed that Grisaldon tends to hinder the course of reparation of bone, whereas choline salicylate gel has no appreciable influence upon the time course of wound healing. This essential difference is considered to be due predominantly to the exactly opposite behavior shown by the two pharmaceutical preparations in regard to their solubility in water. The difficultly watersoluble Grisaldon tends to exert a longer-drawn-out irritant effect upon the tissue and can be detected in alveoli even after twenty-eight days from administration thereof. By contrast, choline salicylate gel, which is known to be readily soluble in water, will be eliminated already after two days from administration thereof. PMID:150157

  14. Highly constrained guests in complexes of p-tert-butylcalix[6]arene dianion: Pentane-1,5-diammonium and choline

    NASA Astrophysics Data System (ADS)

    Lazzarotto, Márcio; Ferreira, Creusa Iara; Castellano, Eduardo Ernesto; Veglia, Alicia Viviana

    2014-06-01

    The structures of the complexes of choline and pentane-1,5-diammonium with p-t-bu-calix[6]arene dianion were determined. Both salts display the calixarene moiety at 1,2,3-alternate conformation, with two concave surfaces formed by three aromatic rings, and the phenolate units are at distal positions, interacting with two phenol units by hydrogen bonds. The salt of pentane-1,5-diammonium shows the diammonium connecting both calixarene dianion units, and one NH3+ is located endo-calix position and the other occupies an exo-calix position. The t-butyl groups and the calix cavity constrains the pentane-1,5-diammonium chain to near syn-eclipsed and gauche conformations. The other semi-calix accomodates a THF solvent molecule. The salt of choline shows the trimethylammonium groups of choline units immersed in these concave surfaces, with several interactions N+-C-H---π interactions with the aromatic semi-cavities.

  15. Iron uptake and metabolism in pseudomonads.

    PubMed

    Cornelis, Pierre

    2010-05-01

    Pseudomonads are ubiquitous Gram-negative gamma proteobacteria known for their extreme versatility and adaptability. Some are plant pathogens (Pseudomonas syringae) which have to survive on the surface of leaves while others can colonize the rhizosphere or survive in soil (Pseudomonas fluorescens, Pseudomonas putida), and one species, Pseudomonas entomophila, is an insect pathogen. The most investigated species, Pseudomonas aeruginosa, is known to be an opportunistic pathogen able to infect plants, nematodes, insects, and mammals, including humans. Like for other bacteria, iron is a key nutrient for pseudomonads. The fluorescent pseudomonads produce siderophores, the best known being the fluorescent high-affinity peptidic pyoverdines. Often diverse secondary siderophores of lower affinity are produced as well (pyochelin, pseudomonin, corrugatins and ornicorrugatins, yersiniabactin, and thioquinolobactin). Reflecting their large capacity of adaptation to changing environment and niche colonization, pseudomonads are able to obtain their iron from heme or from siderophores produced by other microorganisms (xenosiderophores) via the expression of outer membrane TonB-dependent receptors. As expected, iron uptake is exquisitely and hierarchically regulated in these bacteria. In this short review, the diversity of siderophores produced, receptors, and finally the way iron homeostasis is regulated in P. aeruginosa, P. syringae, P. putida, and P. fluorescens, will be presented and, when possible, put in relation with the lifestyle and the ecological niche. PMID:20352420

  16. PRINCIPLES OF AFFINITY-BASED BIOSENSORS

    EPA Science Inventory

    Despite the amount of resources that have been invested by national and international academic, government, and commercial sectors to develop affinity-based biosensor products, little obvious success has been realized through commercialization of these devices for specific applic...

  17. Minimal information to determine affine shape equivalence.

    PubMed

    Wagemans, J; Van Gool, L; Lamote, C; Foster, D H

    2000-04-01

    Participants judged the affine equivalence of 2 simultaneously presented 4-point patterns. Performance level (d') varied between 1.5 and 2.7, depending on the information available for solving the correspondence problem (insufficient in Experiment 1a, superfluous in Experiment 1b, and minimal in Experiments 1c, 2a, 2b) and on the exposure time (unlimited in Experiments 1 and 2a and 500 ms in Experiment 2b), but it did not vary much with the complexity of the affine transformation (rotation and slant in Experiment 1 and same plus tilt in Experiment 2). Performance in Experiment 3 was lower with 3-point patterns than with 4-point patterns, whereas blocking the trials according to the affine transformation parameters had little effect. Determining affine shape equivalence with minimal-information displays is based on a fast assessment of qualitatively or quasi-invariant properties such as convexity/ concavity, parallelism, and collinearity. PMID:10811156

  18. Protein purification using PDZ affinity chromatography.

    PubMed

    Walkup, Ward G; Kennedy, Mary B

    2015-01-01

    PDZ domains function in nature as protein-binding domains within scaffold and membrane-associated proteins. They comprise approximately 90 residues and undergo specific, high-affinity interactions with complementary C-terminal peptide sequences, other PDZ domains, and/or phospholipids. We have previously shown that the specific, strong interactions of PDZ domains with their ligands make them well suited for use in affinity chromatography. This unit provides protocols for the PDZ affinity chromatography procedure that are applicable for the purification of proteins that contain PDZ domains or PDZ domain-binding ligands, either naturally or introduced by genetic engineering. We detail the preparation of affinity resins composed of PDZ domains or PDZ domain peptide ligands coupled to solid supports. These resins can be used to purify proteins containing endogenous or genetically introduced PDZ domains or ligands, eluting the proteins with free PDZ domain peptide ligands. PMID:25829303

  19. Visualizing antibody affinity maturation in germinal centers.

    PubMed

    Tas, Jeroen M J; Mesin, Luka; Pasqual, Giulia; Targ, Sasha; Jacobsen, Johanne T; Mano, Yasuko M; Chen, Casie S; Weill, Jean-Claude; Reynaud, Claude-Agnès; Browne, Edward P; Meyer-Hermann, Michael; Victora, Gabriel D

    2016-03-01

    Antibodies somatically mutate to attain high affinity in germinal centers (GCs). There, competition between B cell clones and among somatic mutants of each clone drives an increase in average affinity across the population. The extent to which higher-affinity cells eliminating competitors restricts clonal diversity is unknown. By combining multiphoton microscopy and sequencing, we show that tens to hundreds of distinct B cell clones seed each GC and that GCs lose clonal diversity at widely disparate rates. Furthermore, efficient affinity maturation can occur in the absence of homogenizing selection, ensuring that many clones can mature in parallel within the same GC. Our findings have implications for development of vaccines in which antibodies with nonimmunodominant specificities must be elicited, as is the case for HIV-1 and influenza. PMID:26912368

  20. Dietary choline deficiency alters global and gene-specific DNA methylation in the developing hippocampus of mouse fetal brains.

    PubMed

    Niculescu, Mihai D; Craciunescu, Corneliu N; Zeisel, Steven H

    2006-01-01

    The availability of choline during critical periods of fetal development alters hippocampal development and affects memory function throughout life. Choline deficiency during fetal development reduces proliferation and migration of neuronal precursor cells in the mouse fetal hippocampus and these changes are associated with modifications in the protein levels of some cell cycle regulators and early differentiation markers. We fed C57 BL/6 mouse dams diets deficient or normal in choline content from days 12 to 17 of pregnancy, and then collected fetal brains on embryonic day 17. Using laser-capture micro-dissection we harvested cells from the ventricular and subventricular zones of Ammon's horn and from the prime germinal zone of the dentate gyrus (hippocampus). In the ventricular and subventricular zones from the choline-deficient group, we observed increased protein levels for kinase-associated phosphatase (Kap) and for p15(INK4b) (two cell cycle inhibitors). In the dentate gyrus, we observed increased levels of calretinin (an early marker of neuronal differentiation). In fetal brain from mothers fed a choline-deficient diet, DNA global methylation was decreased in the ventricular and subventricular zones of Ammon's horn. We also observed decreased gene-specific DNA methylation of the gene (Cdkn3) that encodes for Kap, correlating with increased expression of this protein. This was not the case for p15(INK4b) or calretinin (Cdkn2b and Calb2, respectively). These data suggest that choline deficiency-induced changes in gene methylation could mediate the expression of a cell cycle regulator and thereby alter brain development. PMID:16394266

  1. N-methyl-D-aspartate increases acetylcholine release from rat striatum and cortex: its effect is augmented by choline

    NASA Technical Reports Server (NTRS)

    Ulus, I. H.; Buyukuysal, R. L.; Wurtman, R. J.

    1992-01-01

    We examined the effects of N-methyl-D-aspartate (NMDA), a glutamate agonist, and of glutamate itself, on acetylcholine (ACh) release from superfused rat striatal slices. In a Mg(++)-free medium, NMDA (32-1000 microM) as well as glutamate (1 mM) increased basal ACh release by 35 to 100% (all indicated differences, P less than .05), without altering tissue ACh or choline contents. This augmentation was blocked by Mg++ (1.2 mM) or by MK-801 (10 microM). Electrical stimulation (15 Hz, 75 mA) increased ACh release 9-fold (from 400 to 3660 pmol/mg of protein): this was enhanced (to 4850 pmol/mg of protein) by NMDA (100 microM). ACh levels in stimulated slices fell by 50 or 65% depending on the absence or presence of NMDA. The addition of choline (40 microM) increased ACh release both basally (570 pmol/mg of protein) and with electrical stimulation (6900 pmol/mg of protein). In stimulated slices choline acted synergistically with NMDA, raising ACh release to 10,520 pmol/mg of protein. The presence of choline also blocked the fall in tissue ACh. No treatment affected tissue phospholipid or protein levels. NMDA (32-320 microM) also augmented basal ACh release from cortical but not hippocampal slices. Choline efflux from striatal and cortical (but not hippocampal) slices decreased by 34 to 50% in Mg(++)-free medium. These data indicate that NMDA-like drugs may be useful, particularly in combination with choline, to enhance striatal and cortical cholinergic activity. ACh release from rat hippocampus apparently is not affected by NMDA receptors.

  2. Folate intake and the MTHFR C677T genotype influence choline status in young Mexican American women☆

    PubMed Central

    Abratte, Christian M.; Wang, Wei; Li, Rui; Moriarty, David J.; Caudill, Marie A.

    2009-01-01

    Numerous studies have reported a relationship between folate status, the methylenetetrahydrofolate reductase (MTHFR) 677C→T variant and disease risk. Although folate and choline metabolism are inter-related, only limited data are available on the relationship between choline and folate status in humans. This study sought to examine the influences of folate intake and the MTHFR 677C→T variant on choline status. Mexican-American women (n =43; 14 CC, 12 CT and 17 TT) consumed 135 μg/day as dietary folate equivalents (DFE) for 7 weeks followed by randomization to 400 or 800 μg DFE/day for 7 weeks. Throughout the study, total choline intake remained unchanged at ∼350 mg/day. Plasma concentrations of betaine, choline, glycerophosphocholine, phosphatidylcholine and sphingomyelin were measured via LC-MS/MS for Weeks 0, 7 and 14. Phosphatidylcholine and sphingomyelin declined ( P=.001, P=.009, respectively) in response to folate restriction and increased ( P=.08, P=.029, respectively) in response to folate treatment. The increase in phosphatidylcholine occurred in response to 800 ( P=.03) not 400 ( P=.85) μg DFE/day (week×folate interaction, P=.017). The response of phosphatidylcholine to folate intake appeared to be influenced by MTHFR C677T genotype. The decline in phosphatidylcholine during folate restriction occurred primarily in women with the CC or CT genotype and not in the TT genotype (week×genotype interaction, P=.089). Moreover, when examined independent of folate status, phosphatidylcholine was higher ( P <.05) in the TT genotype relative to the CT genotype. These data suggest that folate intake and the MTHFR C677T genotype influence choline status in humans. PMID:17588738

  3. Sensitivity of binding of high-affinity dopamine receptor radioligands to increased synaptic dopamine.

    PubMed

    Gatley, S J; Gifford, A N; Carroll, F I; Volkow, N D

    2000-12-15

    PET and SPECT studies have documented that D2 radioligands of moderate affinity, but not radioligands of high affinity, are sensitive to pharmacological challenges that alter synaptic dopamine levels. The objective of this work was to determine whether the brain kinetics of high-affinity radioligands for dopamine D1 ([(3)H]SCH 23390) and D2 ([(123)I]epidepride) receptors were altered by a prolonged elevation of synaptic dopamine induced by the potent cocaine analog RTI-55. Mice were injected intravenously with radioligands either 30 min after or 4 h before intraperitoneal administration of RTI-55 (2 mg/kg). In separate experiments, the pharmacological effects of RTI-55 were assessed biochemically by measuring uptake of dopamine in synaptosomes prepared from RTI-treated mice and behaviorally by monitoring locomotor activity. Consistent with the expected elevation of synaptic dopamine, RTI-55 induced a long-lasting decrement in dopamine uptake measured ex vivo, and a prolonged increase in locomotor activity. RTI-55 injected prior to the radioligands induced a significant (P < 0.05) increase in striatal concentration of [(123)I]epidepride at 15 min, relative to saline-treated controls, but there were no differences between the two groups at later time-points. For [(3)H]SCH 23390, both initial striatal uptake and subsequent clearance were slightly increased by preadministration of RTI-55. Administration of RTI-55 4 h after the radioligands (i.e., when it was presumed that a state of near equilibrium binding of the radioligands had been reached), was associated with a significant reduction of striatal radioactivity for both radiotracers. Our results are consistent with increased competition between dopamine and radioligand for binding to both D1 and D2 receptors after treatment with RTI-55. We suggest that the magnitude of the competition is reduced by failure of the receptor binding of high-affinity radioligands to rapidly attain equilibrium. PMID:11044896

  4. Choline availability modulates human neuroblastoma cell proliferation and alters the methylation of the promoter region of the cyclin-dependent kinase inhibitor 3 gene.

    PubMed

    Niculescu, Mihai D; Yamamuro, Yutaka; Zeisel, Steven H

    2004-06-01

    Choline is an important methyl donor and a component of membrane phospholipids. In this study, we tested the hypothesis that choline availability can modulate cell proliferation and the methylation of genes that regulate cell cycling. In several other model systems, hypomethylation of cytosine bases that are followed by a guanosine (CpG) sites in the promoter region of a gene is associated with increased gene expression. We found that in choline-deficient IMR-32 neuroblastoma cells, the promoter of the cyclin-dependent kinase inhibitor 3 gene (CDKN3) was hypomethylated. This change was associated with increased expression of CDKN3 and increased levels of its gene product, kinase-associated phosphatase (KAP), which inhibits the G(1)/S transition of the cell cycle by dephosphorylating cyclin-dependent kinases. Choline deficiency also reduced global DNA methylation. The percentage of cells that accumulated bromodeoxyuridine (proportional to cell proliferation) was 1.8 times lower in the choline-deficient cells than in the control cells. Phosphorylated retinoblastoma (p110) levels were 3 times lower in the choline-deficient cells than in control cells. These findings suggest that the mechanism whereby choline deficiency inhibits cell proliferation involves hypomethylation of key genes regulating cell cycling. This may be a mechanism for our previously reported observation that stem cell proliferation in hippocampus neuroepithelium is decreased in choline-deficient rat and mouse fetuses. PMID:15147518

  5. Choline availability modulates human neuroblastoma cell proliferation and alters the methylation of the promoter region of the cyclin-dependent kinase inhibitor 3 gene

    PubMed Central

    Niculescu, Mihai D.; Yamamuro, Yutaka; Zeisel, Steven H.

    2006-01-01

    Choline is an important methyl donor and a component of membrane phospholipids. In this study, we tested the hypothesis that choline availability can modulate cell proliferation and the methylation of genes that regulate cell cycling. In several other model systems, hypomethylation of cytosine bases that are followed by a guanosine (CpG) sites in the promoter region of a gene is associated with increased gene expression. We found that in choline-deficient IMR-32 neuroblastoma cells, the promoter of the cyclin-dependent kinase inhibitor 3 gene (CDKN3) was hypomethylated. This change was associated with increased expression of CDKN3 and increased levels of its gene product, kinase-associated phosphatase (KAP), which inhibits the G1/S transition of the cell cycle by dephosphorylating cyclin-dependent kinases. Choline deficiency also reduced global DNA methylation. The percentage of cells that accumulated bromodeoxyuridine (proportional to cell proliferation) was 1.8 times lower in the choline-deficient cells than in the control cells. Phosphorylated retinoblastoma (p110) levels were 3 times lower in the choline-deficient cells than in control cells. These findings suggest that the mechanism whereby choline deficiency inhibits cell proliferation involves hypomethylation of key genes regulating cell cycling. This may be a mechanism for our previously reported observation that stem cell proliferation in hippocampus neuroepithelium is decreased in choline-deficient rat and mouse fetuses. PMID:15147518

  6. Pre-Conditioning with CDP-Choline Attenuates Oxidative Stress-Induced Cardiac Myocyte Death in a Hypoxia/Reperfusion Model

    PubMed Central

    González-Pacheco, Héctor; Méndez-Domínguez, Aurelio; Hernández, Salomón; López-Marure, Rebeca; Vazquez-Mellado, Maria J.; Aguilar, Cecilia; Rocha-Zavaleta, Leticia

    2014-01-01

    Background. CDP-choline is a key intermediate in the biosynthesis of phosphatidylcholine, which is an essential component of cellular membranes, and a cell signalling mediator. CDP-choline has been used for the treatment of cerebral ischaemia, showing beneficial effects. However, its potential benefit for the treatment of myocardial ischaemia has not been explored yet. Aim. In the present work, we aimed to evaluate the potential use of CDP-choline as a cardioprotector in an in vitro model of ischaemia/reperfusion injury. Methods. Neonatal rat cardiac myocytes were isolated and subjected to hypoxia/reperfusion using the coverslip hypoxia model. To evaluate the effect of CDP-choline on oxidative stress-induced reperfusion injury, the cells were incubated with H2O2 during reperfusion. The effect of CDP-choline pre- and postconditioning was evaluated using the cell viability MTT assay, and the proportion of apoptotic and necrotic cells was analyzed using the Annexin V determination by flow cytometry. Results. Pre- and postconditioning with 50 mg/mL of CDP-choline induced a significant reduction of cells undergoing apoptosis after hypoxia/reperfusion. Preconditioning with CDP-choline attenuated postreperfusion cell death induced by oxidative stress. Conclusion. CDP-choline administration reduces cell apoptosis induced by oxidative stress after hypoxia/reperfusion of cardiac myocytes. Thus, it has a potential as cardioprotector in ischaemia/reperfusion-injured cardiomyocytes. PMID:24578622

  7. EFFECT OF HUMIC ACID ON UPTAKE AND TRANSFER OF COPPER FROM MICROBES TO CILIATES TO COPEPODS

    EPA Science Inventory

    This research is part of an ongoing project designed to determine the effect of humic acid on the uptake and transfer of metals by marine organisms at the lower end of the food chain. Binding affinities for Cu, Cd, Zn, and Cr to Suwannee River humic acid were determined at variou...

  8. Electrochemical Deposition of Niobium onto the Surface of Copper Using a Novel Choline Chloride-Based Ionic Liquid

    SciTech Connect

    Wixtroma, Alex I.; Buhlera, Jessica E.; Reece, Charles E.; Abdel-Fattah, Tarek M.

    2013-06-01

    Recent research has shown that choline chloride-based solutions can be used to replace acid-based electrochemical polishing solutions. In this study niobium metal was successfully deposited on the surface of copper substrate via electrochemical deposition using a novel choline chloride-based ionic liquid. The niobium metal used for deposition on the Cu had been dissolved in the solution from electrochemical polishing of a solid niobium piece prior to the deposition. The visible coating on the surface of the Cu was analyzed using scanning electron microscopy (SEM) and electron dispersive x-ray spectroscopy (EDX). This deposition method effectively recycles previously dissolved niobium from electrochemical polishing.

  9. Assessing therapy response of secreting pineal germ cell tumor on simultaneous 18F-choline PET/MRI.

    PubMed

    Panagiotidis, Emmanouil; Shankar, Ananth; Afaq, Asim; Bomanji, Jamshed

    2014-09-01

    An 18-year-old man presented with 6 weeks' history of diplopia, early morning headaches, and blurred vision; on ophthalmologic examination, Parinaud syndrome was revealed. Brain MRI scan showed a calcified pineal mass. Brain simultaneous PET/MRI with 18F-choline showed an avid enhancing mass occupying the pineal region with restricted diffusion. A second examination after chemotherapy demonstrated reduction in both size and radiotracer activity of the mass. Our study emphasizes the potential of simultaneous 18F-choline PET/MRI being a useful tool for contribution in the diagnosis and treatment assessment in a convenient way with minimal radiation exposure and reduced throughput patient time. PMID:24217533

  10. Dietary choline regulates antibacterial activity, inflammatory response and barrier function in the gills of grass carp (Ctenopharyngodon idella).

    PubMed

    Zhao, Hua-Fu; Jiang, Wei-Dan; Liu, Yang; Jiang, Jun; Wu, Pei; Kuang, Sheng-Yao; Tang, Ling; Tang, Wu-Neng; Zhang, Yong-An; Zhou, Xiao-Qiu; Feng, Lin

    2016-05-01

    An 8-week feeding trial was conducted to determine the effects of graded levels of choline (197-1795 mg/kg) on antibacterial properties, inflammatory status and barrier function in the gills of grass carp. The results showed that optimal dietary choline supplementation significantly improved lysozyme and acid phosphatase activities, complement component 3 (C3) content, and the liver expressed antimicrobial peptide 2 and Hepcidin mRNA levels in the gills of fish (P < 0.05). In addition, appropriate dietary choline significantly decreased the oxidative damage, which might be partly due to increase copper, zinc superoxide dismutase (Cu/Zn-SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and glutathione reductase (GR) activities and increased glutathione content in the gills of fish (P < 0.05). Moreover, appropriate dietary choline significantly up-regulated the mRNA levels of interleukin 10 and transforming growth factor β1, Zonula occludens 1, Occludin, Claudin-b, c, 3 and 12, inhibitor of κBα, target of rapamycin, Cu/Zn-SOD, CAT, GR, GPx, GST and NF-E2-related factor 2 in the gills of fish (P < 0.05). Conversely, appropriate dietary choline significantly down-regulated the mRNA levels of pro-inflammatory cytokines, tumor necrosis factor α, interleukin 8, interferon γ, interleukin 1β, and related signaling factors, nuclear factor kappa B p65, IκB kinase β, IκB kinase γ, myosin light chain kinase and Kelch-like-ECH-associated protein 1a (Keap1a) in the gills of fish (P < 0.05). However, choline did not have a significant effect on the mRNA levels of IκB kinase α, Claudin-15 and Keap1b in the gills of fish. Collectively, appropriate dietary choline levels improved gill antibacterial properties and relative gene expression levels of tight junction proteins, and decreased inflammatory status, as well as up-regulated the mRNA levels of related signaling molecules in the gills of fish. Based on gill C3 content and AHR

  11. Non-enzymatic synthesis of the coenzymes, uridine diphosphate glucose and cytidine diphosphate choline, and other phosphorylated metabolic intermediates

    NASA Technical Reports Server (NTRS)

    Mar, A.; Dworkin, J.; Oro, J.

    1987-01-01

    Using urea and cyanamide, the two condensing agents considered to have been present on the primitive earth, uridine diphosphate glucose (UDPG), cytidine diphosphate choline (CDP-choline), glucose-1-phosphate (G1P), and glucose-6-phosphate (G6P) were synthesized under simulated prebiotic conditions. The reaction products were separated and identified using paper chromatography, thin layer chromatography, enzymatic analyses, and ion-pair reverse-phase high performance liquid chromatography. The possibility of nonenzymatic synthesis of metabolic intermediates on the primitive earth from simple precursors was thus demonstrated.

  12. Hydride transfer made easy in the oxidation of alcohols catalyzed by choline oxidase

    SciTech Connect

    Gadda, G.; Orville, A.; Pennati, A.; Francis, K.; Quaye, O.; Yuan, H.; Rungsrisuriyachai, K.; Finnegan, S.; Mijatovic, S.; Nguyen, T.

    2008-06-08

    Choline oxidase (E.C. 1.1.3.17) catalyzes the two-step, four-electron oxidation of choline to glycine betaine with betaine aldehyde as enzyme-associated intermediate and molecular oxygen as final electron acceptor (Scheme 1). The gem-diol, hydrated species of the aldehyde intermediate of the reaction acts as substrate for aldehyde oxidation, suggesting that the enzyme may use similar strategies for the oxidation of the alcohol substrate and aldehyde intermediate. The determination of the chemical mechanism for alcohol oxidation has emerged from biochemical, mechanistic, mutagenetic, and structural studies. As illustrated in the mechanism of Scheme 2, the alcohol substrate is initially activated in the active site of the enzyme by removal of the hydroxyl proton. The resulting alkoxide intermediate is then stabilized in the enzyme-substrate complex via electrostatic interactions with active site amino acid residues. Alcohol oxidation then occurs quantum mechanically via the transfer of the hydride ion from the activated substrate to the N(5) flavin locus. An essential requisite for this mechanism of alcohol oxidation is the high degree of preorganization of the activated enzyme-substrate complex, which is achieved through an internal equilibrium of the Michaelis complex occurring prior to, and independently from, the subsequent hydride transfer reaction. The experimental evidence that support the mechanism for alcohol oxidation shown in Scheme 2 is briefly summarized in the Results and Discussion section.

  13. Glutamate and Choline Levels Predict Individual Differences in Reading Ability in Emergent Readers

    PubMed Central

    Frost, Stephen J.; Rothman, Douglas L.; Hoeft, Fumiko; Del Tufo, Stephanie N.; Mason, Graeme F.; Molfese, Peter J.; Mencl, W. Einar; Grigorenko, Elena L.; Landi, Nicole; Preston, Jonathan L.; Jacobsen, Leslie; Seidenberg, Mark S.; Fulbright, Robert K.

    2014-01-01

    Reading disability is a brain-based difficulty in acquiring fluent reading skills that affects significant numbers of children. Although neuroanatomical and neurofunctional networks involved in typical and atypical reading are increasingly well characterized, the underlying neurochemical bases of individual differences in reading development are virtually unknown. The current study is the first to examine neurochemistry in children during the critical period in which the neurocircuits that support skilled reading are still developing. In a longitudinal pediatric sample of emergent readers whose reading indicators range on a continuum from impaired to superior, we examined the relationship between individual differences in reading and reading-related skills and concentrations of neurometabolites measured using magnetic resonance spectroscopy. Both continuous and group analyses revealed that choline and glutamate concentrations were negatively correlated with reading and related linguistic measures in phonology and vocabulary (such that higher concentrations were associated with poorer performance). Correlations with behavioral scores obtained 24 months later reveal stability for the relationship between glutamate and reading performance. Implications for neurodevelopmental models of reading and reading disability are discussed, including possible links of choline and glutamate to white matter anomalies and hyperexcitability. These findings point to new directions for research on gene-brain-behavior pathways in human studies of reading disability. PMID:24623786

  14. Alcohol consumption significantly influences the MR signal of frontal choline-containing compounds.

    PubMed

    Ende, Gabriele; Walter, Sigi; Welzel, Helga; Demirakca, Traute; Wokrina, Tim; Ruf, Matthias; Ulrich, Marco; Diehl, Alexander; Henn, Fritz A; Mann, Karl

    2006-08-15

    The aim of this work was to evaluate the relationship between the amount of alcohol consumption of a group of social drinkers and the magnetic resonance spectroscopy signal of choline-containing compounds (Cho) in the frontal lobe. Two independent long echo (TE = 135 ms) (1)H MRSI studies, the first comprising 24 subjects with very low alcohol consumption, the second 18 subjects with a more widespread alcohol consumption were conducted. Significant correlations of Cho measures from frontal white matter and from the anterior cingulate gyrus with alcohol consumption in the last 90 days prior to the MR examination were found. Age, gender, and smoking did not show significant effects on the metabolite measures. Partialling out the effect of the voxel white matter content did not change the correlation of choline measures with alcohol consumption. The main conclusion from the repeated finding of a positive correlation of alcohol consumption and frontal Cho signals is that monitoring for alcohol consumption is mandatory in MRS studies where pathology depended Cho changes are hypothesized. PMID:16759881

  15. In vitro inhibition of choline acetyltransferase by a series of 2-benzylidene-3-quinuclidinones

    SciTech Connect

    Capacio, B.R.

    1988-01-01

    Ten substituted 2-benzylidene-3-quinuclidinones were synthesized and evaluated for their relative potency as in vitro inhibitors of choline acetyltransferase (ChAT). Acetylcholine (ACh) synthesis was followed radiometrically by the incorporation of labeled acetate originating from {sup 14}C-acetyl-CoA. Woolf-Augustinsson-Hofstee data analysis was used to calculate Vmax, Km, and Ki values. The inhibition was found to be noncompetitive or uncompetitive with respect to choline. Quantitative structure activity relationship correlations demonstrated a primary dependence on {kappa}-{sigma}, as well as steric properties of the substituted benzene ring. Additional radiometric and spectrophotometric were performed with 2-(3{prime}-methyl)-benzylidene-3-quinuclidinone, one of the more potent analogs, to further elucidate the inhibitory mechanism. ChAT-mediated cleavage of ACh was measured spectrophotometrically by following the appearance of NADH at 340 nanometers in an enzyme coupled assay. Lineweaver-Burk analysis indicated mixed or uncompetitive inhibition with respect to both substrates of the forward reaction, suggesting interference with a rate limiting step.

  16. Multisite monitoring of choline using biosensor microprobe arrays in combination with CMOS circuitry.

    PubMed

    Frey, Olivier; Rothe, Jörg; Heer, Flavio; van der Wal, Peter D; de Rooij, Nico F; Hierlemann, Andreas

    2014-08-01

    A miniature device enabling parallel in vivo detection of the neurotransmitter choline in multiple brain regions of freely behaving rodents is presented. This is achieved by combining a biosensor microprobe array with a custom-developed CMOS chip. Each silicon microprobe comprises multiple platinum electrodes that are coated with an enzymatic membrane and a permselective layer for selective detection of choline. The biosensors, based on the principle of amperometric detection, exhibit a sensitivity of 157±35 µA mM(-1) cm(-2), a limit of detection of below 1 µM, and a response time in the range of 1 s. With on-chip digitalization and multiplexing, parallel recordings can be performed at a high signal-to-noise ratio with minimal space requirements and with substantial reduction of external signal interference. The layout of the integrated circuitry allows for versatile configuration of the current range and can, therefore, also be used for functionalization of the electrodes before use. The result is a compact, highly integrated system, very convenient for on-site measurements. PMID:24145056

  17. Choline Kinase β Mutant Mice Exhibit Reduced Phosphocholine, Elevated Osteoclast Activity, and Low Bone Mass*

    PubMed Central

    Kular, Jasreen; Tickner, Jennifer C.; Pavlos, Nathan J.; Viola, Helena M.; Abel, Tamara; Lim, Bay Sie; Yang, Xiaohong; Chen, Honghui; Cook, Robert; Hool, Livia C.; Zheng, Ming Hao; Xu, Jiake

    2015-01-01

    The maintenance of bone homeostasis requires tight coupling between bone-forming osteoblasts and bone-resorbing osteoclasts. However, the precise molecular mechanism(s) underlying the differentiation and activities of these specialized cells are still largely unknown. Here, we identify choline kinase β (CHKB), a kinase involved in the biosynthesis of phosphatidylcholine, as a novel regulator of bone homeostasis. Choline kinase β mutant mice (flp/flp) exhibit a systemic low bone mass phenotype. Consistently, osteoclast numbers and activity are elevated in flp/flp mice. Interestingly, osteoclasts derived from flp/flp mice exhibit reduced sensitivity to excessive levels of extracellular calcium, which could account for the increased bone resorption. Conversely, supplementation of cytidine 5′-diphosphocholine in vivo and in vitro, a regimen that bypasses CHKB deficiency, restores osteoclast numbers to physiological levels. Finally, we demonstrate that, in addition to modulating osteoclast formation and function, loss of CHKB corresponds with a reduction in bone formation by osteoblasts. Taken together, these data posit CHKB as a new modulator of bone homeostasis. PMID:25451916

  18. Choline kinase alpha expression during RA-induced neuronal differentiation: role of C/EBPβ.

    PubMed

    Domizi, Pablo; Aoyama, Chieko; Banchio, Claudia

    2014-04-01

    Neuronal differentiation is a complex process characterized by a halt in proliferation and extension of neurites from the cell body. This process is accompanied by changes in gene expression that mediate the redirection leading to neurite formation and function. Acceleration of membrane phospholipids synthesis is associated with neurite elongation, and phosphatidylcholine (PtdCho) is the major membrane phospholipid in mammalian cells. The transcription of two genes in particular encoding key enzymes in the CDP-choline pathway for PtdCho biosynthesis are stimulated; the Chka gene for choline kinase (CK) alpha isoform and the Pcyt1a gene for the CTP:phosphocholine cytidylyltransferase (CCT) alpha isoform. We report that the stimulation of CKα expression during retinoic acid (RA) induced differentiation depends on a promoter region that contains two CCAAT/Enhancer-binding Protein-β (C/EBPβ) sites. We demonstrate that during neuronal differentiation of Neuro-2a cells, RA induces Chka expression by a mechanism that involves ERK1/2 activation which triggers C/EBPβ expression. Elevated levels of C/EBPβ bind to the Chka proximal promoter (Box1) inducing CKα expression. In addition we identified a downstream sequence named Box2 which together with Box1 is required for the promoter to reach the full induction. This is the first elucidation of the mechanism by which the expression of Chka is coordinately regulated during neuronal differentiation. PMID:24440820

  19. Direct determination of the driving forces for taurocholate uptake into rat liver plasma membrane vesicles.

    PubMed

    Duffy, M C; Blitzer, B L; Boyer, J L

    1983-10-01

    To determine directly the driving forces for bile acid entry into the hepatocyte, the uptake of [3H]taurocholic acid into rat liver plasma membrane vesicles was studied. The membrane preparation contained predominantly right-side-out vesicles, and was highly enriched in plasma membrane marker enzymes. The uptake of taurocholate at equilibrium was inversely related to medium osmolarity, indicating transport into an osmotically sensitive space. In the presence of an inwardly directed sodium gradient (NaCl or sodium gluconate), the initial rate of uptake was rapid and taurocholate was transiently accumulated at a concentration twice that at equilibrium (overshoot). Other inwardly directed cation gradients (K+, Li+, choline+) or the presence of sodium in the absence of a gradient (Na+ equilibrated) resulted in a slower initial uptake rate and did not sustain an overshoot. Bile acids inhibited sodium-dependent taurocholate uptake, whereas bromsulphthalein inhibited both sodium-dependent and sodium-independent uptake and D-glucose had no effect on uptake. Uptake was temperature dependent, with maximal overshoots occurring at 25 degrees C. Imposition of a proton gradient across the vesicle (pHo less than pHi) in the absence of a sodium gradient failed to enhance taurocholate uptake, indicating that double ion exchange (Na+-H+, OH- -anion) is unlikely. Creation of a negative intravesicular potential by altering accompanying anions or by valinomycin-induced K+-diffusion potentials did not enhance taurocholate uptake, suggesting an electroneutral transport mechanism. The kinetics of taurocholate uptake demonstrated saturability with a Michaelis constant at 52 microM and maximum velocity of 4.5 nmol X mg-1 X protein X min-1. These studies provide definitive evidence for a sodium gradient-dependent, carrier-mediated, electrically neutral transport mechanism for hepatic taurocholate uptake. These findings are consistent with a model for bile secretion in which the basolateral

  20. D