De novo synthesis of phospholipids and sphingomyelin in multipotent stromal cells - Monitoring studies by mass spectrometry

2020 ◽  
Vol 232 ◽  
pp. 104965
Author(s):  
Patricia Prabutzki ◽  
Jenny Leopold ◽  
Susanna Schubert ◽  
Jürgen Schiller ◽  
Ariane Nimptsch
Keyword(s):  
Mass Spectrometry ◽  
Stromal Cells ◽  
De Novo ◽  
Multipotent Stromal Cells ◽  
De Novo Synthesis

De Novo Synthesis of 4,5-Dimethoxycatechol and 2,5-Dimethoxyhydroquinone by the Brown Rot FungusGloeophyllum trabeum

1999 ◽  
Vol 65 (2) ◽  
pp. 674-679 ◽  
Author(s):  
Andrzej Paszczynski ◽  
Ronald Crawford ◽  
David Funk ◽  
Barry Goodell
Keyword(s):  
Mass Spectrometry ◽  
Methylene Chloride ◽  
De Novo ◽  
Brown Rot ◽  
Gas Chromatography Mass Spectrometry ◽  
Gloeophyllum Trabeum ◽  
De Novo Synthesis ◽  
Brown Rot Fungus ◽  
Synthetic Standard ◽  
Brown Rot Decay

ABSTRACT The new dimethoxycatechol 4,5-dimethoxy-1,2-benzenediol (DMC) and the new dimethoxyhydroquinone 2,5-dimethoxy-1,4-benzenediol (DMH) were isolated from stationary cultures of the brown rot fungusGloeophyllum trabeum growing on a glucose mineral medium protected from light. The structure was elucidated by gas chromatography-mass spectrometry through comparison to a synthetic standard. Further confirmation was obtained by forming a dimethoxyoxazole derivative by condensation of DMC with methylene chloride and through examination of methylated derivatives. DMC and DMH may serve as ferric chelators, oxygen-reducing agents, and redox-cycling molecules, which would include functioning as electron transport carriers to Fenton’s reactions. Thus, they appear to be important components of the brown rot decay system of the fungus.

scholarly journals Functional Heterogeneity of Protein Kinase A Activation in Multipotent Stromal Cells

2020 ◽  
Vol 21 (12) ◽  
pp. 4442
Author(s):  
Pyotr A. Tyurin-Kuzmin ◽  
Maxim N. Karagyaur ◽  
Konstantin Yu. Kulebyakin ◽  
Daniyar T. Dyikanov ◽  
Vadim I. Chechekhin ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Protein Kinase A ◽  
Stromal Cells ◽  
Molecular Mechanisms ◽  
De Novo ◽  
Multipotent Stromal Cells ◽  
Adenylyl Cyclases ◽  
Functional Heterogeneity ◽  
Pka Pathway ◽  
Kinase A

Multipotent stromal cells (MSC) demonstrate remarkable functional heterogeneity; however, its molecular mechanisms remain largely obscure. In this study, we explored MSC response to hormones, which activate Gs-protein / cyclic AMP (cAMP) / protein kinase A (PKA) dependent signaling, at the single cell level using genetically encoded biosensor PKA-Spark. For the first time, we demonstrated that about half of cultured MSCs are not able to activate the cAMP/PKA pathway, possibly due to the limited availability of adenylyl cyclases. Using this approach, we showed that MSC subpopulations responding to various hormones largely overlapped, and the share of responding cells did not exceed 40%. Using clonal analysis, we showed that signaling heterogeneity of MSC could be formed de novo within 2 weeks.

Distribution of Newly Formed Fatty Acids Among Glycerolipids of Isolated Perfused Rat Liver

1975 ◽  
Vol 53 (5) ◽  
pp. 509-518 ◽  
Author(s):  
A. Kuksis ◽  
J. J. Myher ◽  
L. Marai ◽  
S. K. F. Yeung ◽  
I. Steiman ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Fatty Acids ◽  
Gas Chromatography ◽  
Subcellular Distribution ◽  
Blood Cells ◽  
De Novo ◽  
Acyl Transfer ◽  
Isolated Perfused Rat Liver ◽  
Perfused Rat Liver ◽  
De Novo Synthesis

Livers of chow fed rats were perfused 1–3 h with buffer, glucose, albumin, and red blood cells, made up in 100% D2O. Glycerolipids were isolated and the deuterated fatty acids determined by gas chromatography with mass spectrometry on Silar 5 CP. Percentage of replacement by deuterated acids ranged from 1 to 14, of which palmitate was 87%. Differences were found in total lipid class and in subcellular distribution of the newly synthesized acids. Microsomes had 37% more deuterated acids than the total or floating fat. At 3 h the highest replacement was found in diacylglycerols (17%) and free fatty acids (11%). Of the palmitate in hepatic choline and ethanolamine phosphatides, 6.9% and 4.7%, respectively, contained dueterium. The serine and inositol phosphatides had a higher proportion of deuterated palmitate (7.7%) than other phosphatides. The data support the hypothesis that palmitate is incorporated into glycerolipids largely via de novo synthesis while stearate enters them by deacylation – acyl transfer replacement.

scholarly journals Metabolic flux analysis of the neural cell glycocalyx reveals differential utilization of monosaccharides

Glycobiology ◽  
2020 ◽  
Vol 30 (11) ◽  
pp. 859-871
Author(s):  
Maurice Wong ◽  
Gege Xu ◽  
Mariana Barboza ◽  
Izumi Maezawa ◽  
Lee-Way Jin ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Cell Differentiation ◽  
Metabolic Flux Analysis ◽  
Metabolic Flux ◽  
Isotope Labeling ◽  
De Novo ◽  
Cell Metabolism ◽  
Flux Analysis ◽  
De Novo Synthesis ◽  
Direct Incorporation

Abstract Saccharides in our diet are major sources of carbon for the formation of biomass such as proteins, lipids, nucleic acids and glycans. Among the dietary monosaccharides, glucose occupies a central role in metabolism, but human blood contains regulated levels of other monosaccharides as well. Their influence on metabolism and how they are utilized have not been explored thoroughly. Applying metabolic flux analysis on glycan synthesis can reveal the pathways that supply glycosylation precursors and provide a snapshot of the metabolic state of the cell. In this study, we traced the incorporation of six 13C uniformly labeled monosaccharides in the N-glycans, O-glycans and glycosphingolipids of both pluripotent and neural NTERA-2 cells. We gathered detailed isotopologue data for hundreds of glycoconjugates using mass spectrometry methods. The contributions of de novo synthesis and direct incorporation pathways for glucose, mannose, fructose, galactose, N-acetylglucosamine and fucose were determined based on their isotope incorporation. Co-feeding studies revealed that fructose incorporation is drastically decreased by the presence of glucose, while mannose and galactose were much less affected. Furthermore, increased sialylation slowed down the turnover of glycans, but fucosylation attenuated this effect. Our results demonstrated that exogenous monosaccharide utilization can vary markedly depending on the cell differentiation state and monosaccharide availability, and that the incorporation of carbons can also differ among different glycan structures. We contend that the analysis of metabolic isotope labeling of glycans can yield new insights about cell metabolism.

Characterization of Monocyte-Associated Factor V

1993 ◽  
Vol 70 (02) ◽  
pp. 273-280 ◽  
Author(s):  
Janos Kappelmayer ◽  
Satya P Kunapuli ◽  
Edward G Wyshock ◽  
Robert W Colman
Keyword(s):  
Monoclonal Antibody ◽  
Light Chain ◽  
Peripheral Blood ◽  
De Novo ◽  
Factor V ◽  
Blood Monocytes ◽  
De Novo Synthesis ◽  
Hep G2 ◽  
Hep G2 Cells ◽  
Peripheral Blood Monocytes

SummaryWe demonstrate that in addition to possessing binding sites for intact factor V (FV), unstimulated peripheral blood monocytes also express activated factor V (FVa) on their surfaces. FVa was identified on the monocyte surface by monoclonal antibody B38 recognizing FVa light chain and by human oligoclonal antibodies H1 (to FVa light chain) and H2 (to FVa heavy chain) using immunofluorescence microscopy and flow cytometry. On Western blots, partially cleaved FV could be identified as a 220 kDa band in lysates of monocytes. In addition to surface expression of FVa, monocytes also contain intracellular FV as detected only after permeabilization by Triton X-100 by monoclonal antibody B10 directed specifically to the Cl domain not present in FVa. We sought to determine whether the presence of FV in peripheral blood monocytes is a result of de novo synthesis.Using in situ hybridization, no FV mRNA could be detected in monocytes, while in parallel control studies, factor V mRNA was detectable in Hep G2 cells and CD18 mRNA in monocytes. In addition, using reverse transcriptase and the polymerase chain reaction, no FV mRNA was detected in mononuclear cells or in U937 cells, but mRNA for factor V was present in Hep G2 cells using the same techniques. These data suggest that FV is present in human monocytes, presumably acquired by binding of plasma FV, and that the presence of this critical coagulation factor is not due to de novo synthesis.

Platelets Stimulate Thromboplastin Synthesis in Human Endothelial Cells

1983 ◽  
Vol 49 (02) ◽  
pp. 069-072 ◽  
Author(s):  
U L H Johnsen ◽  
T Lyberg ◽  
K S Galdal ◽  
H Prydz
Keyword(s):  
Endothelial Cells ◽  
De Novo ◽  
Umbilical Vein ◽  
Time Dependent ◽  
De Novo Synthesis ◽  
Human Endothelial Cells ◽  
Tumor Promotor ◽  
Coagulation Assay ◽  
Platelet Aggregates ◽  
Umbilical Vein Endothelial Cells

SummaryHuman umbilical vein endothelial cells in culture synthesize thromboplastin upon stimulation with phytohaemagglutinin (PHA) or the tumor promotor 12-O-tetradecanoyl-phorbol-13-acetate (TPA). The thromboplastin activity is further strongly enhanced in a time dependent reaction by the presence of gel-filtered platelets or platelet aggregates. This effect was demonstrable at platelet concentrations lower than those normally found in plasma, it may thus be of pathophysiological relevance. The thromboplastin activity increased with increasing number of platelets added. Cycloheximide inhibited the increase, suggesting that de novo synthesis of the protein component of thromboplastin, apoprotein III, is necessary.When care was taken to remove monocytes no thromboplastin activity and no apoprotein HI antigen could be demonstrated in suspensions of gel-filtered platelets, platelets aggregated with thrombin or homogenized platelets when studied with a coagulation assay and an antibody neutralization technique.

DE NOVO SYNTHESIS OF STEROIDS BY THE TESTES OF THE HUMAN FOETUS AT MIDGESTATION

1971 ◽  
Vol 68 (1_Supplb) ◽  
pp. S135 ◽  
Author(s):  
R. S. Mathur ◽  
N. Wiqvist ◽  
E. Diczfalusy
Keyword(s):  
De Novo ◽  
De Novo Synthesis ◽  
Human Foetus
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