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Environmental Health Perspectives Dec 1985The reduction of oxygen by the ene-diol tautomer of simple monosaccharides produces hydrogen peroxide and alpha-oxoaldehydes. This process, termed monosaccharide...
The reduction of oxygen by the ene-diol tautomer of simple monosaccharides produces hydrogen peroxide and alpha-oxoaldehydes. This process, termed monosaccharide autoxidation, occurs at physiological pH and temperature and may contribute to the development of several pathological processes. Enolization of the monosaccharide to an ene-diol tautomer is a prerequisite for the reaction of the monosaccharides with oxygen. The reaction kinetics suggest a two step process: the enolization of the monosaccharide to the ene-diol followed by the reaction of the ene-diol with oxygen. Free-radical reactive intermediates are formed by the reaction of the ene-diol with oxygen: superoxide, semidione, and 1-hydroxyalkyl radicals are formed under physiological conditions (hydroxyl radicals are also detected at high pH). The autoxidation of monosaccharides stimulates the oxidation of oxyhemoglobin in erythrocytes, producing methemoglobin and hydrogen peroxide, and the oxidation of reduced pyridine nucleotides NAD(P)H to the oxidized congener NAD(P)+ and enzymatically inactive nucleotide. This stimulates oxidative metabolism (via the hexose monophosphate shunt) and alpha-oxoaldehyde metabolism (via the glyoxalase system) in erythrocytes in vitro. The oxidative challenge is relatively mild even with very high concentrations (50 mM) of monosaccharide. However, crosslinking of membrane proteins by alpha-oxoaldehydes is enhanced; this effect may exacerbate ageing and decrease the lifetime of erythrocytes in circulation. In vivo, the autoxidation of monosaccharides is expected to be a chronic oxidative process occurring in biological tissue which utilises simple monosaccharides, e.g., in glycolysis and gluconeogenesis. Monosaccharide autoxidation is suggested to be a determinant in the control of cellular mitosis and ageing, providing physiological substrates for the glyoxalase system, and may contribute to the chronic disease processes associated with diabetes mellitus and the smoking of tobacco.
Topics: Aging; Carbohydrate Metabolism; Disease; Electron Spin Resonance Spectroscopy; Free Radicals; Humans; Hydrogen Peroxide; Kinetics; Mitosis; Monosaccharides; NAD; NADP; Oxidation-Reduction; Oxygen Consumption
PubMed: 3007096
DOI: 10.1289/ehp.8564297 -
Bioconjugate Chemistry Aug 2022Methylcyclopropene (Cyoc)-tagged tetra-acetylated monosaccharides, and in particular mannosamine derivatives, are promising tools for medical imaging of cancer using...
Methylcyclopropene (Cyoc)-tagged tetra-acetylated monosaccharides, and in particular mannosamine derivatives, are promising tools for medical imaging of cancer using metabolic oligosaccharide engineering and the extremely fast inverse electron-demand Diels-Alder bioorthogonal reaction. However, the potential of these monosaccharide derivatives has yet to be fully explored due to their low aqueous solubility. To address this issue, we sought to vary the extent of acetylation of Cyoc-tagged monosaccharides and probe its effect on the extent of glycan labeling in various cancer cell lines. We demonstrate that, in the case of AcManNCyoc, tri- and diacetylated derivatives generated significantly enhanced cell labeling compared to the tetra-acetylated monosaccharide. In contrast, for the more readily soluble azide-tagged sugars, a decrease in acetylation led to decreased glycan labeling. AcManNCyoc gave better labeling than the azido-tagged AcManNAz and has significant potential for and imaging of glycosylated cancer biomarkers.
Topics: Acetylation; Monosaccharides; Neoplasms; Polysaccharides; Staining and Labeling
PubMed: 35876696
DOI: 10.1021/acs.bioconjchem.2c00169 -
Cellular and Molecular Life Sciences :... May 2009A large number of compounds mimicking the structures of monosaccharides or oligosaccharides have been discovered from natural sources. Such sugar mimics inhibit... (Review)
Review
A large number of compounds mimicking the structures of monosaccharides or oligosaccharides have been discovered from natural sources. Such sugar mimics inhibit carbohydrate-degrading enzymes because of a structural resemblance to the sugar moiety of the natural substrate. Carbohydrate-degrading enzymes are involved in a wide range of important biological processes, such as intestinal digestion, posttranslational processing of the sugar chain of glycoproteins, their quality control mechanisms, lysosomal catabolism of glycoconjugates, and some viral infections. It has now been realized that inhibitors of the enzymes have enormous therapeutic potential in diabetes and lysosomal storage disorders. In this review, the general bioactivity, current applications, and the prospects for new therapeutic applications are described.
Topics: Animals; Binding, Competitive; Carbohydrate Metabolism; Diabetes Mellitus; Enzyme Inhibitors; Glycogen; Glycoside Hydrolases; Humans; Lysosomal Storage Diseases; Mice; Monosaccharides; Protein Folding; Rabbits; Rats
PubMed: 19132292
DOI: 10.1007/s00018-008-8522-3 -
Seminars in Cell & Developmental Biology Aug 2010In the last decade, over 40 inherited human glycosylation disorders were identified. Most patients have hypomorphic, rather than null alleles. The phenotypic spectrum is... (Review)
Review
In the last decade, over 40 inherited human glycosylation disorders were identified. Most patients have hypomorphic, rather than null alleles. The phenotypic spectrum is broad and most of the disorders affect embryonic and early post-natal development; a few appear in adult life. Some deficiencies can be treated with simple dietary sugar (monosaccharide) supplements. Here we focus on four glycosylation disorders that have been treated with supplements in patients or in model systems, primarily the mouse. Surprisingly, small differences in the amount of exogenous sugar have a major impact on the diseases in specific cells or organs while others are unaffected. The underlying mechanisms are mostly unknown, but changes in the contributions of the de novo, salvage and dietary pathways may contribute to the beneficial outcome. Clearly, the metabolic chart is not flat; all arrows are not equally robust at all points of time and space. This metabolic perspective may help explain some of these observations and guide the development of other vertebrate models of glycosylation disorders that can respond to dietary manipulation.
Topics: Animals; Disease Models, Animal; Glycosylation; Humans; Metabolism, Inborn Errors; Monosaccharides; Phenotype; Polysaccharides
PubMed: 20363348
DOI: 10.1016/j.semcdb.2010.03.011 -
Jornal de Pediatria 2019This narrative review aimed to provide practitioners a synthesis of the current knowledge on the role of a low Fermentable Oligosaccharides Disaccharides Monosaccharides... (Review)
Review
OBJECTIVE
This narrative review aimed to provide practitioners a synthesis of the current knowledge on the role of a low Fermentable Oligosaccharides Disaccharides Monosaccharides and Polyols diet in reducing symptoms associated with functional abdominal pain disorders in children. This review is focused on the pathophysiology, efficacy and criticism of low Fermentable Oligosaccharides Disaccharides Monosaccharides and Polyols diet in children.
SOURCES
Cochrane Database, Pubmed and Embase were searched using specific terms for Fermentable Oligosaccharides Disaccharides Monosaccharides and Polyols diet interventions and functional abdominal pain disorders.
SUMMARY OF THE FINDINGS
In children, only one Randomized Control Trial and one open-label study reported positive results of low Fermentable Oligosaccharides Disaccharides Monosaccharides and Polyols diet; one Randomized Control Trial showed exacerbation of symptoms with fructans in children with Irritable Bowel Syndrome; no effect was found for the lactose-free diet whilst fructose-restricted diets were effective in 5/6 studies.
CONCLUSIONS
In children there are few trials evaluating low Fermentable Oligosaccharides Disaccharides Monosaccharides and Polyols in functional abdominal pain disorders, with encouraging data on the therapeutic efficacy particularly of fructose-restricted diet. Additional efforts are still needed to fill this research gap and clarify the most efficient way for tailoring dietary restrictions based on the patient's tolerance and/or identification of potential biomarkers of low Fermentable Oligosaccharides Disaccharides Monosaccharides and Polyols efficacy, to maintain nutritional adequacy and to simplify the adherence to diet by labeling Fermentable Oligosaccharides Disaccharides Monosaccharides and Polyols content in commercial products.
Topics: Abdominal Pain; Diet; Diet, Carbohydrate-Restricted; Disaccharides; Humans; Irritable Bowel Syndrome; Monosaccharides; Oligosaccharides
PubMed: 31028745
DOI: 10.1016/j.jped.2019.03.004 -
Physiologia Plantarum Jan 2023Plants adapt to freezing stress through cold acclimation, which is induced by nonfreezing low temperatures and accompanied by growth arrest. A later increase in...
Plants adapt to freezing stress through cold acclimation, which is induced by nonfreezing low temperatures and accompanied by growth arrest. A later increase in temperature after cold acclimation leads to rapid loss of freezing tolerance and growth resumption, a process called deacclimation. Appropriate regulation of the trade-off between freezing tolerance and growth is necessary for efficient plant development in a changing environment. The cell wall, which mainly consists of polysaccharide polymers, is involved in both freezing tolerance and growth. Still, it is unclear how the balance between freezing tolerance and growth is affected during cold acclimation and deacclimation by the changes in cell wall structure and what role is played by its monosaccharide composition. Therefore, to elucidate the regulatory mechanisms controlling freezing tolerance and growth during cold acclimation and deacclimation, we investigated cell wall changes in detail by sequential fractionation and monosaccharide composition analysis in the model plant Arabidopsis thaliana, for which a plethora of information and mutant lines are available. We found that arabinogalactan proteins and pectic galactan changed in close coordination with changes in freezing tolerance and growth during cold acclimation and deacclimation. On the other hand, arabinan and xyloglucan did not return to nonacclimation levels after deacclimation but stabilized at cold acclimation levels. This indicates that deacclimation does not completely restore cell wall composition to the nonacclimated state but rather changes it to a specific novel composition that is probably a consequence of the loss of freezing tolerance and provides conditions for growth resumption.
Topics: Freezing; Acclimatization; Cold Temperature; Arabidopsis; Cell Wall; Monosaccharides; Arabidopsis Proteins; Gene Expression Regulation, Plant
PubMed: 36461890
DOI: 10.1111/ppl.13837 -
BioMed Research International 2014Glycosaminoglycans (GAGs) play an important role in many biological processes in the extracellular matrix. In a theoretical approach, structures of monosaccharide...
Glycosaminoglycans (GAGs) play an important role in many biological processes in the extracellular matrix. In a theoretical approach, structures of monosaccharide building blocks of natural GAGs and their sulfated derivatives were optimized by a B3LYP6311ppdd//B3LYP/6-31+G(d) method. The dependence of the observed conformational properties on the applied methodology is described. NMR chemical shifts and proton-proton spin-spin coupling constants were calculated using the GIAO approach and analyzed in terms of the method's accuracy and sensitivity towards the influence of sulfation, O1-methylation, conformations of sugar ring, and ω dihedral angle. The net sulfation of the monosaccharides was found to be correlated with the (1)H chemical shifts in the methyl group of the N-acetylated saccharides both theoretically and experimentally. The ω dihedral angle conformation populations of free monosaccharides and monosaccharide blocks within polymeric GAG molecules were calculated by a molecular dynamics approach using the GLYCAM06 force field and compared with the available NMR and quantum mechanical data. Qualitative trends for the impact of sulfation and ring conformation on the chemical shifts and proton-proton spin-spin coupling constants were obtained and discussed in terms of the potential and limitations of the computational methodology used to be complementary to NMR experiments and to assist in experimental data assignment.
Topics: Glycosaminoglycans; Magnetic Resonance Spectroscopy; Models, Molecular; Molecular Conformation; Molecular Dynamics Simulation; Monosaccharides; Protons; Quantum Theory
PubMed: 24804247
DOI: 10.1155/2014/808071 -
Alimentary Pharmacology & Therapeutics Jun 2015Dietary fibre supplements have been advocated for the management of chronic constipation (CC) and irritable bowel syndrome (IBS). Recently, a fermentable... (Review)
Review
BACKGROUND
Dietary fibre supplements have been advocated for the management of chronic constipation (CC) and irritable bowel syndrome (IBS). Recently, a fermentable oligosaccharide, disaccharide, monosaccharide and polyol (FODMAP) restricted diet has been recommended for IBS.
AIM
To systematically examine recent evidence for dietary interventions with fibre in CC and IBS and FODMAP-restricted diet in IBS, and provide recommendations.
METHODS
We searched PUBMED, MEDLINE, OVID and COCHRANE databases from 2004 to 2014. Published studies in adults with CC and IBS and constipation-predominant IBS (IBS-C) that compared fibre with placebo/alternative and FODMAP-restricted diet with alternative were included.
RESULTS
Of 550 potentially eligible clinical trials on fibre, 11 studies were found and of 23 potentially eligible studies on FODMAPs, six were found. A meta-analysis was not performed due to heterogeneity and methodological quality. Fibre was beneficial in 5/7 studies in CC and 3/3 studies in IBS-C. FODMAP-restricted diet improved overall IBS symptoms in 4/4 and IBS-C symptoms in 1/3 studies and three studies did not meet inclusion criteria. There were significant disparities in subject selection, interventions and outcome assessments in both fibre and FODMAPs studies.
CONCLUSIONS
Fibre supplementation is beneficial in mild to moderate CC and IBS-C, although larger, more rigorous and long-term RCTs are needed (Fair evidence-Level II, Grade B). Although the FODMAP-restricted diet may be effective in short-term management of selected patients with IBS (Fair evidence-Level II, Grade C) and IBS-C (Poor evidence-Level III, Grade C), more rigorous trials are needed to establish long-term efficacy and safety, particularly on colonic health and microbiome.
Topics: Adult; Constipation; Diet Therapy; Dietary Fiber; Disaccharides; Disease Management; Fermentation; Humans; Irritable Bowel Syndrome; Monosaccharides; Oligosaccharides; Polymers
PubMed: 25903636
DOI: 10.1111/apt.13167 -
International Journal of Molecular... Sep 2022The edible fungus was shown to have a high molecular weight (1.87 × 10 kDa) bioactive polysaccharide, denoted as TFP-F1. Monosaccharide composition and NMR analysis of...
The edible fungus was shown to have a high molecular weight (1.87 × 10 kDa) bioactive polysaccharide, denoted as TFP-F1. Monosaccharide composition and NMR analysis of the polysaccharide and its derivatives indicated it contained fucose (Fuc), xylose (Xyl), mannose (Man), and glucuronic acid (GlcA) in a ratio of 0.9:1.0:3.2:1.2. Using IR, NMR, and GC-MS spectroscopic data, the structure of TFP-F1 was elucidated as {→3)-[-D-GlcA-(1→2)]--D-Man-(1→3)--D-Man-(1→3)-[-L-Fuc-(1→2)--D-Xyl-(1→2)]--D-Man-(1→}, with partial acetylation of C6-OH in mannoses. Furthermore, at a concentration of 1 μg/mL, TFP-F1 was found to stimulate the secretion of TNF-α and IL-6 in J774A.1 macrophage cells in vitro via interaction with toll-like receptor 4 (TLR4). The removal of -acetyl groups led to the loss of immunomodulatory activities, demonstrating that -acetyl groups play an essential role in enhancing the production of pro-inflammatory cytokines.
Topics: Acetylation; Basidiomycota; Cytokines; Dietary Carbohydrates; Fucose; Glucuronic Acid; Immunomodulation; Interleukin-6; Mannose; Monosaccharides; Polysaccharides; Toll-Like Receptor 4; Tumor Necrosis Factor-alpha; Xylose
PubMed: 36142298
DOI: 10.3390/ijms231810392 -
FEBS Letters May 2007Mesophyll cells and most types of storage cells harbor large central vacuoles representing the main cellular store for sugars and other primary metabolites like... (Review)
Review
Mesophyll cells and most types of storage cells harbor large central vacuoles representing the main cellular store for sugars and other primary metabolites like carboxylic- or and amino acids. The general biochemical characteristics of sugar transport across the vacuolar membrane are already known since a couple of years but only recently the first tonoplast sugar carriers have been identified on the molecular level. A candidate sucrose carrier has been identified in a proteomic approach. In Arabidopsis, the tonoplast monosaccharide transporters (TMT) represent a small protein family comprising only three members, which reside in the vacuolar membrane. Two of three tmt genes are induced upon cold, drought or salt stress and tmt knock out mutants exhibit altered monosaccharide levels upon cold induction. These observations indicate that TMT proteins represent the first examples of tonoplast sugar carriers involved in the cellular response upon osmotic stress stimuli.
Topics: Arabidopsis; Arabidopsis Proteins; Biological Transport, Active; Carbohydrate Metabolism; Disaccharides; Genes, Plant; Intracellular Membranes; Monosaccharide Transport Proteins; Monosaccharides; Osmotic Pressure; Plants; Vacuoles
PubMed: 17307167
DOI: 10.1016/j.febslet.2007.02.003