Rat kidney microsomal fraction is able to catalyze the enzymatic desaturation of eicosatrienoic acid (20:3n-6) to arachidonic acid (20:4n-6) by the delta 5 desaturase pathway, in the presence of reduced nicotinamide adenine dinucleotide (NADH), adenosinetriphosphate (ATP) and coenzyme A (CoA). The substrate of the reaction [1-14C]eicosa-8,11,14-trienoic acid (20:3n-6), was separated from the product [1-14C]eicosa-5,8,11,14-tetraenoic acid (20:4n-6) by reverse phase high-pressure liquid chromatography (RP-HPLC). These fatty acids were individually collected by monitoring the eluent at 205 nm and their radioactivity was measured by liquid scintillation counting. The delta 5 desaturase activity in kidney microsomes increased linearly with the substrate concentration up to 20 microM. Enzymatic activity was sensitive to pH with the maximum at 7.0 and was proportional with incubation time up to 10 min. The apparent Km and Vmax of delta 5 desaturase were 56 microM and 60 pmoles.min-1.mg-1 microsomal protein, respectively. Neither the cytosolic renal fraction nor the cytosolic liver fraction enhanced the delta 5 desaturase activity. Contrary to a report but in accordance to others, the present results suggest that rat kidneys can synthesize arachidonic acid at least to satisfy partially their needs for eicosanoid production.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/BF00926573 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
High levels of serum dihomo-γ-linolenic acid are associated with non-alcoholic fatty liver disease in type 2 diabetic patients.
Diabetol Int
January 2025
Division of Diabetes, Metabolism, and Endocrinology, Department of Medicine, Toho University Graduate School of Medicine, Tokyo, Japan.
An elevated level of saturated fatty acids (SFAs) can cause non-alcoholic fatty liver disease (NAFLD). While n-3 polyunsaturated fatty acids (PUFAs) were shown to improve NAFLD, the effects of n-6 PUFAs in the liver have not been fully elucidated. We examined the association between NAFLD and n-6 PUFAs, particularly dihomo-γ-linolenic acid (DGLA), in patients with type 2 diabetes.
View Article and Find Full Text PDFDocosahexaenoic and Eicosapentaenoic Acid Supplementation Could Attenuate Negative Effects of Maternal Metabolic Syndrome on Liver Lipid Metabolism and Liver Betacellulin Expression in Male and Female Rat Offspring.
Metabolites
January 2025
Department of Chemistry and Biochemistry, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10000 Zagreb, Croatia.
: This study investigated the effects of maternal metabolic syndrome during pregnancy on hepatic fatty acid metabolism and betacellulin expression in rat offspring. A rat model of maternal metabolic syndrome was created with a high-fructose diet (15% fructose in drinking water for six months). : The females with metabolic syndrome were divided into the CON group, the HF group, which received fructose in drinking water, and the HF-DHA group, which received fructose in water and increased amounts of DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid) in the diet (2.
View Article and Find Full Text PDFGenetically Predicted Gene Expression Effects on Changes in Red Blood Cell and Plasma Polyunsaturated Fatty Acids.
Genet Epidemiol
January 2025
Division of Epidemiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, USA.
Polyunsaturated fatty acids (PUFAs) including omega-3 and omega-6 are obtained from diet and can be measured objectively in plasma or red blood cells (RBCs) membrane biomarkers, representing different dietary exposure windows. In vivo conversion of omega-3 and omega-6 PUFAs from short- to long-chain counterparts occurs via a shared metabolic pathway involving fatty acid desaturases and elongase. This analysis leveraged genome-wide association study (GWAS) summary statistics for RBC and plasma PUFAs, along with expression quantitative trait loci (eQTL) to estimate tissue-specific genetically predicted gene expression effects for delta-5 desaturase (FADS1), delta-6 desaturase (FADS2), and elongase (ELOVL2) on changes in RBC and plasma biomarkers.
View Article and Find Full Text PDFSpecific activity of mouse liver desaturases and elongases: Time course effects using n-3 and n-6 PUFA substrates and inhibitory responses of delta-6 desaturase.
Biochim Biophys Acta Mol Cell Biol Lipids
January 2025
Department of Nutritional Sciences, Temerty Faculty of Medicine, University of Toronto, Toronto, Canada.
The synthesis of n-3 and n-6 polyunsaturated acids (PUFAs) is associated with physiological functions in mammals, being catalyzed by Δ-5D and Δ-6D desaturases and elongases Elovl-2 and Elovl-5. In this context, we aimed to study the chief kinetic features of PUFA liver anabolism, looking upon (i) the time-dependency for the specific activity of Δ-6D, Δ-5D, Elovl2, Elovl2/5 and Elovl5, using n-3 and n-6 precursors between 0 and 240 min ex vivo in mouse liver.; and (ii) the specific activity-substrate (α-linolenic acid; ALA) concentration responses of Δ-6D in the absence and presence of linoleic acid (LA), arachidonic acid (ARA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), an enzyme regarded as the rate-limiting step in PUFA anabolism.
View Article and Find Full Text PDFSupplying LSD1 with FAD in pancreatic cancer: A matter of protein-protein interaction?
Arch Biochem Biophys
February 2025
Department of Biosciences, Biotechnologies, and Environment, University of Bari Aldo Moro, Italy. Electronic address:
Lysine-specific demethylase 1 (LSD1) is a key regulator in cancer epigenetic, and its activity is reliant on flavin adenine dinucleotide (FAD) as a cofactor. In this study, we investigated the correlation between LSD1 and FAD synthase isoform 2 (FADS2) protein levels in pancreatic ductal adenocarcinoma (PDAC) cell lines. We first assessed LSD1 protein and mRNA levels in mutant p53-expressing PANC-1 and MiaPaCa2 cells and p53-null AsPc-1 cells, compared to human pancreatic ductal epithelial (HPDE) controls.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!