scholarly journals Polyunsaturated-fatty-acid oxidation in Hydra: regioselectivity, substrate-dependent enantioselectivity and possible biological role

1994 ◽  
Vol 300 (2) ◽  
pp. 501-507 ◽  
Author(s):  
V Di Marzo ◽  
C Gianfrani ◽  
L De Petrocellis ◽  
A Milone ◽  
G Cimino
Keyword(s):  
Fatty Acids ◽  
Arachidonic Acid ◽  
Acid Oxidation ◽  
Reaction Products ◽  
Double Bonds ◽  
Regenerative Processes ◽  
Hydra Vulgaris ◽  
Degree Of Unsaturation ◽  
Keto Acids ◽  
Linoelaidic Acid

A novel and abundant lipoxygenase-like activity converting cis-eicosa-5,8,11,14-tetraenoic acid (arachidonic acid) into (11R)-hydroxyeicosatetraenoic acid has been recently described in homogenates of the freshwater hydrozoan Hydra vulgaris. In this study, other substrates for this enzyme were selected from the polyunsaturated fatty acids (PUFAs) present in H. vulgaris, and the chemical natures of the hydroperoxy and hydroxy derivatives produced, as well as the activity of some of the latter on hydroid tentacle regeneration, were investigated. The highest conversion among C20 fatty acids was observed for arachidonic acid, and among C18 fatty acids for cis-octadeca-9,12,15- and cis-octadeca-6,9,12-trienoic (alpha- and gamma-linolenic) acids. Cis double bonds on the 10th carbon atom from the aliphatic end of the substrate (e.g. C-9, C-11 and C-13 respectively in C18, C20 and C22 PUFAs) were regiospecifically peroxidized. Conversely, trans-octadeca-9,12-dienoic (linoelaidic) acid was not a substrate for lipoxygenase activity. Enantioselectivity of lipoxygenation depended on the degree of unsaturation of the substrate, with the amount of the R enantiomer increasing when passing, for example, from cis-eicosa-11,14-dienoic to cis-eicosa-5,8,11,14,17-pentaenoic acid. Regiospecific formation of keto acids was observed only when incubating C18 PUFAs. Commercially available hydroxyacids corresponding to the reaction products of some of the most abundant H. vulgaris PUFAs were tested for effects on Hydra tentacle regeneration. An enhancement of average tentacle number, in a fashion depending on the stereochemistry and on the number of double bonds, was found for two compounds, thus suggesting for the 11-lipoxygenase-like enzyme a role in the production of metabolites potentially active in the control of hydroid regenerative processes.

Effect of unilateral ureteral obstruction on metabolism of renal lipids in the rat

1983 ◽  
Vol 245 (2) ◽  
pp. F254-F262
Author(s):  
J. Tannenbaum ◽  
M. L. Purkerson ◽  
S. Klahr
Keyword(s):  
Fatty Acids ◽  
Arachidonic Acid ◽  
Oleic Acid ◽  
Ureteral Obstruction ◽  
Total Phospholipid ◽  
Unilateral Ureteral Obstruction ◽  
Phospholipid Content ◽  
Acid Oxidation ◽  
Contralateral Kidney

The metabolism of lipids in the cortex and inner medulla of control and experimental kidneys of rats with unilateral ureteral obstruction (UUO) was studied in vitro. A marked increase in the tissue triglyceride content was noted after 24 h of obstruction in the experimental kidney compared with the contralateral kidney of rats with UUO and normal kidneys from sham-operated rats. A decrease in total phospholipid content was seen in the experimental kidney after 24 h of obstruction. The incorporation of [1-14C]oleic acid or [14C]arachidonic acid into tissue triglycerides was significantly increased in the cortex and medulla of the experimental kidney of rats with UUO compared with either the contralateral kidney of the same animals or kidneys from sham-operated rats. The oxidation of [1-14C]oleic acid to 14CO2 and the incorporation of [14C]arachidonic acid into tissue phospholipids or free fatty acids were significantly lower in the experimental kidney of rats with UUO. The results strongly suggest an increase in the net synthetic rate of triglycerides in the experimental kidney of UUO rats. This increase may be related to both a decrease in fatty acid oxidation and an increased release of fatty acids from phospholipids presumably due to increased phospholipase activity.

Effect of degree of unsaturation in dietary fatty acids on arachidonic acid mobilization by peritoneal macrophages

Lipids ◽  
1996 ◽  
Vol 31 (6) ◽  
pp. 661-666 ◽  
Author(s):  
María T. Mitjavila ◽  
María C. Rodríguez ◽  
María P. Sáiz ◽  
Sergio Lloret ◽  
Juan J. Moreno
Keyword(s):  
Fatty Acids ◽  
Arachidonic Acid ◽  
Peritoneal Macrophages ◽  
Dietary Fatty Acids ◽  
Degree Of Unsaturation

On the Reaction of 2,5-Dihydroxy-[1,4]-benzoquinone with Diamines – Strain-induced Reactivity Effects

2020 ◽  
Vol 24 ◽  
Author(s):  
Hubert Hettegger ◽  
Andreas Hofinger ◽  
Thomas Rosenau
Keyword(s):  
Nucleophilic Substitution ◽  
Product Structure ◽  
Carbonyl Groups ◽  
Reaction Products ◽  
Double Bonds ◽  
Oh Groups ◽  
Natural Geometry ◽  
Quinoid Structure ◽  
Bond Localization

: The regioselectivity of the reaction of 2,5-dihydroxy-[1,4]-benzoquinone (DHBQ) with diamines could not be explained satisfactorily so far. In general, the reaction products can be derived from the tautomeric ortho-quinoid structure of a hypothetical 4,5-dihydroxy-[1,2]-benzoquinone. However, both aromatic and aliphatic 1,2-diamines form in some cases phenazines, formally by diimine formation on the quinoid carbonyl groups, and in other cases the corresponding 1,2- diamino-[1,2]-benzoquinones, by nucleophilic substitution of the OH groups, the regioselectivity apparently not following any discernible pattern. The reactivity was now explained by an adapted theory of strain-induced bond localization (SIBL). Here, the preservation of the "natural" geometry of the two quinoid C–C double bonds (C3=C4 and C5=C6) as well as the N–N distance of the co-reacting diamine are crucial. A decrease of the annulation angle sum (N–C4–C5 + C4–C5–N) is tolerated well and the 4,5-diamino-ortho-quinones, having relatively short N–N spacings are formed. An increase in the angular sum is energetically unfavorable, so that diamines with a larger N–N distance afford the corresponding ortho-quinone imines. Thus, for the reaction of DHBQ with diamines, exact predictions of the regioselectivity, and the resulting product structure, can be made on the basis of simple computations of bond spacings and product geometries.

scholarly journals Impact of n-6 Polyunsaturated Fatty Acids on Growth of Multidrug-Resistant Pseudomonas aeruginosa: Interactions with Amikacin and Ceftazidime

2000 ◽  
Vol 44 (8) ◽  
pp. 2187-2189 ◽  
Author(s):  
E. J. Giamarellos-Bourboulis ◽  
P. Grecka ◽  
A. Dionyssiou-Asteriou ◽  
H. Giamarellou
Keyword(s):  
Fatty Acids ◽  
Pseudomonas Aeruginosa ◽  
Arachidonic Acid ◽  
Experimental Infection ◽  
Multidrug Resistant ◽  
Gamma Linolenic Acid ◽  
Infection Models ◽  
Over Time ◽  
In Vitro Interactions

ABSTRACT Twenty-six multidrug-resistant Pseudomonas aeruginosaisolates were exposed over time to 300 μg of gamma-linolenic acid or arachidonic acid per ml or to the combination of both acids at 150 μg/ml each with ceftazidime and amikacin with or without albumin to observe the in vitro interactions of the antibiotics. Antibiotics and albumin were applied at their levels found in serum. Synergy between acids and antibiotics was found against 13 isolates, and it was expressed after 5 h of growth in the presence of albumin. The results indicate that further application in experimental infection models is merited.

scholarly journals Mitochondrial Fission Governed by Drp1 Regulates Exogenous Fatty Acid Usage and Storage in Hela Cells

Metabolites ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 322
Author(s):  
Jae-Eun Song ◽  
Tiago C. Alves ◽  
Bernardo Stutz ◽  
Matija Šestan-Peša ◽  
Nicole Kilian ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Oxidation ◽  
Lipid Droplets ◽  
Mitochondrial Fission ◽  
Acid Oxidation ◽  
Mitochondrial Morphology ◽  
Mitochondrial Fatty Acid Oxidation ◽  
Mitochondrial Fatty Acid ◽  
And Storage

In the presence of high abundance of exogenous fatty acids, cells either store fatty acids in lipid droplets or oxidize them in mitochondria. In this study, we aimed to explore a novel and direct role of mitochondrial fission in lipid homeostasis in HeLa cells. We observed the association between mitochondrial morphology and lipid droplet accumulation in response to high exogenous fatty acids. We inhibited mitochondrial fission by silencing dynamin-related protein 1(DRP1) and observed the shift in fatty acid storage-usage balance. Inhibition of mitochondrial fission resulted in an increase in fatty acid content of lipid droplets and a decrease in mitochondrial fatty acid oxidation. Next, we overexpressed carnitine palmitoyltransferase-1 (CPT1), a key mitochondrial protein in fatty acid oxidation, to further examine the relationship between mitochondrial fatty acid usage and mitochondrial morphology. Mitochondrial fission plays a role in distributing exogenous fatty acids. CPT1A controlled the respiratory rate of mitochondrial fatty acid oxidation but did not cause a shift in the distribution of fatty acids between mitochondria and lipid droplets. Our data reveals a novel function for mitochondrial fission in balancing exogenous fatty acids between usage and storage, assigning a role for mitochondrial dynamics in control of intracellular fuel utilization and partitioning.

Ozonolysis of unsaturated fatty acids. II. Esterification of the total products from the oxidative decomposition of ozonides with 2,2-dimethoxypropane

1967 ◽  
Vol 45 (13) ◽  
pp. 1405-1410 ◽  
Author(s):  
John D. Castell ◽  
R. G. Ackman
Keyword(s):  
Fatty Acids ◽  
Liquid Chromatography ◽  
Unsaturated Fatty Acids ◽  
Performic Acid ◽  
Acid Oxidation ◽  
Gas Liquid Chromatography ◽  
Positional Isomers ◽  
Flame Ionization ◽  
Hydrogen Flame

The total acidic products from the performic acid oxidation of the ozonide of methyl oleate formed in methanol may be esterified directly in a few hours with 2,2-dimethoxypropane. The ester concentrations are adequate for the determination of the positional isomers of monoethylenic fatty acids directly from the reaction mixture, using a hydrogen flame ionization gas–liquid chromatography detector. Dimethyl sulfoxide was not required to prevent the breakdown of 2,2-dimethoxypropane under the conditions employed.

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