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Title: Exogenous gangliosides may affect methylation mechanisms in neuronal cell cultures

Abstract

Primary neurons in culture from chick embryo cerebral hemispheres were treated with a mixture of gangliosides added to the growth medium (final concentration: 10(-5)M and 10(-8)M) from the 3rd to the 6th day in vitro. Under these conditions methylation processes measured with (3H) and (35S) methionine and (3H)ethanolamine as precursors showed an increased methylation of (3H)ethanolamine containing phospholipids, a correspondent increased conversion of these compounds to (3H)choline containing phospholipids, and a general increased methylation of trichloroacetic acid precipitable macromolecules containing labeled methionine. A small increase in protein synthesis was observed after incubation of neurons with (3H)- and (35S)methionine. This was confirmed after electrophoretic separation of a protein extract with increased 3H- and 35S-labeling in protein bands with moecular weights between 50 and 60 KDaltons. A protein band of about 55 KDaltons appeared to be preferentially labelled when (3H) methionine was the precursor. The treatment with gangliosides increased the incorporation of (methyl-3H) label after incubation of neurons with (3H) methionine, into total DNA and decreased that of total RNA. The treatment of neurons in culture with exogenous gangliosides hence affects differently methylation processes, a finding which may confirm the involvement of gangliosides on the intracellular mediation of neuronal information mechanisms.

Authors:
; ; ;  [1]
  1. (Centre de Neurochimie du CNRS, Strasbourg (France))
Publication Date:
OSTI Identifier:
5031766
Resource Type:
Journal Article
Resource Relation:
Journal Name: Neurochemical Research; (United States); Journal Volume: 16:2
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; GANGLIOSIDES; BIOCHEMICAL REACTION KINETICS; NERVE CELLS; BIOCHEMISTRY; PHOSPHOLIPIDS; METHYLATION; BRAIN; CELL CULTURES; CHICKENS; CHOLINE; DNA; EMBRYOS; METHIONINE; MOLECULAR WEIGHT; RNA; SULFUR 35; TRACER TECHNIQUES; TRITIUM COMPOUNDS; ALCOHOLS; AMINES; AMINO ACIDS; AMMONIUM COMPOUNDS; ANIMAL CELLS; ANIMALS; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; BIRDS; BODY; CARBOHYDRATES; CARBOXYLIC ACIDS; CENTRAL NERVOUS SYSTEM; CHEMICAL REACTIONS; CHEMISTRY; DAYS LIVING RADIOISOTOPES; DRUGS; ESTERS; EVEN-ODD NUCLEI; FOWL; GLYCOLIPIDS; HYDROGEN COMPOUNDS; HYDROXY COMPOUNDS; ISOTOPE APPLICATIONS; ISOTOPES; KINETICS; LIGHT NUCLEI; LIPIDS; LIPOTROPIC FACTORS; NERVOUS SYSTEM; NUCLEI; NUCLEIC ACIDS; ORGANIC ACIDS; ORGANIC COMPOUNDS; ORGANIC PHOSPHORUS COMPOUNDS; ORGANIC SULFUR COMPOUNDS; ORGANS; QUATERNARY COMPOUNDS; RADIOISOTOPES; REACTION KINETICS; SACCHARIDES; SOMATIC CELLS; SULFUR ISOTOPES; VERTEBRATES; 550201* - Biochemistry- Tracer Techniques

Citation Formats

Ferret, B., Hubsch, A., Dreyfus, H., and Massarelli, R.. Exogenous gangliosides may affect methylation mechanisms in neuronal cell cultures. United States: N. p., 1991. Web. doi:10.1007/BF00965701.
Ferret, B., Hubsch, A., Dreyfus, H., & Massarelli, R.. Exogenous gangliosides may affect methylation mechanisms in neuronal cell cultures. United States. doi:10.1007/BF00965701.
Ferret, B., Hubsch, A., Dreyfus, H., and Massarelli, R.. 1991. "Exogenous gangliosides may affect methylation mechanisms in neuronal cell cultures". United States. doi:10.1007/BF00965701.
@article{osti_5031766,
title = {Exogenous gangliosides may affect methylation mechanisms in neuronal cell cultures},
author = {Ferret, B. and Hubsch, A. and Dreyfus, H. and Massarelli, R.},
abstractNote = {Primary neurons in culture from chick embryo cerebral hemispheres were treated with a mixture of gangliosides added to the growth medium (final concentration: 10(-5)M and 10(-8)M) from the 3rd to the 6th day in vitro. Under these conditions methylation processes measured with (3H) and (35S) methionine and (3H)ethanolamine as precursors showed an increased methylation of (3H)ethanolamine containing phospholipids, a correspondent increased conversion of these compounds to (3H)choline containing phospholipids, and a general increased methylation of trichloroacetic acid precipitable macromolecules containing labeled methionine. A small increase in protein synthesis was observed after incubation of neurons with (3H)- and (35S)methionine. This was confirmed after electrophoretic separation of a protein extract with increased 3H- and 35S-labeling in protein bands with moecular weights between 50 and 60 KDaltons. A protein band of about 55 KDaltons appeared to be preferentially labelled when (3H) methionine was the precursor. The treatment with gangliosides increased the incorporation of (methyl-3H) label after incubation of neurons with (3H) methionine, into total DNA and decreased that of total RNA. The treatment of neurons in culture with exogenous gangliosides hence affects differently methylation processes, a finding which may confirm the involvement of gangliosides on the intracellular mediation of neuronal information mechanisms.},
doi = {10.1007/BF00965701},
journal = {Neurochemical Research; (United States)},
number = ,
volume = 16:2,
place = {United States},
year = 1991,
month = 2
}
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  • Trichloroethylene (TCE)-transforming aquifer methanotrophs were evaluated for the influence of TCE oxidation toxicity and the effect of reductant availability on TCE transformation rates during methane starvation. TCE oxidation at relatively low (6 mg liter{sup {minus}1}) TCE concentrations significantly reduced subsequent methane utilization in mixed and pure cultures tested and reduced the number of viable cells in the pure culture Methylomonas sp. strain MM2 by an order of magnitude. Perchloroethylene, tested at the same concentration, had no effect on the cultures. Neither the TCE itself nor the aqueous intermediates were responsible for the toxic effect, and it is suggested that TCEmore » oxidation toxicity may have resulted from reactive intermediates that attacked cellular macromolecules. During starvation, all methanotrophs tested exhibited a decline in TCE transformation rates, and this decline followed exponential decay. Formate, provided as an exogenous electron donor, increased TCE transformation rates in Methylomonas sp. strain MM2, but not in mixed culture MM1 or unidentified isolate, CSC-1. Mixed culture MM2 did not transform TCE after 15 h of starvation, but mixed cultures MM1 and MM3 did. The methanotrophs in mixed cultures MM1 and MM3, and the unidentified isolate CSC-1 that was isolated from mixed culture MM1 contained lipid inclusions, whereas the methanotrophs of mixed culture MM2 and Methylomonas sp. strain MM2 did not. It is proposed that lipid storage granules serve as an endogenous source of electrons for TCE oxidation during methane starvation.« less