Sources of eicosanoid precursor fatty acid pools in tissues

Abstract

Tissue arachidonic acid (AA) pools originate from the diet, and from hepatic and extrahepatic desaturationelongation of dietary linoleic acid (LA). This review summarizes the roles of absorption, transport, and formation of AA in the buildup of tissue AA pools. In humans who ingest 0.2-0.3 g of AA and 10-20 g of LA per day on a Western diet, the formation of AA from LA exceeds the dietary supply of AA. A number of factors favor the partitioning of AA to tissue phospholipids rather than adipose tissue and plasma triglycerides. The characteristics of AA transport with lipoproteins are discussed with focus on the role of lipoprotein lipase, lecithin:cholesterol acyltransferase, hepatic lipase, and the scavenger receptor BI and LDL receptors in tissue uptake of AA. Liver-derived 2-acyl-lysophosphatidylcholine and plasma free AA are two important sources of AA for extrahepatic tissues which exhibit a low rate of uptake of lipoprotein AA. Desaturation-elongation of LA to produce AA occurs both in liver and in extrahepatic tissues, plasma free LA being an important substrate particularly during fasting. The AA preference of the reacylation and transacylation reactions is crucial for the selective retention of AA in phospholipids. -Zhou, L., and Å. Nilsson. Sources of eicosanoid precursor fatty acid pools in tissues.

N-6 and n-3 fatty acid cholesteryl esters in relation to incident stroke in a Dutch adult population: A nested case–control study

“…Cholesteryl ester levels of linoleic acid, alpha-linolenic acid, EPA, and DHA are considered a reliable proxy of dietary intake of n-3 PUFA during the previous weeks [14,15], because they are not (alpha-linolenic acid and linoleic acid) or hardly (EPA and DHA) endogenously synthesized [9]. In Western diets, arachidonic levels are more influenced by synthesis from linoleic acid than by dietary intake [7].…”

“…Linoleic acid, belonging to the n-6 PUFA family, is the most abundant PUFA in the diet and it is mainly obtained from vegetable oils, such as sunflower oil and soybean oil [6]. It is an essential fatty acid that can be elongated to arachidonic acid, which is also present in meat in small quantities [7,8]. Alpha-linolenic acid is an essential fatty acid of the n-3 PUFA family and is present in soybean, canola, and flaxseed oil [6].…”

Systemic Metabolic Alterations Correlate with Islet-Level Prostaglandin E2 Production and Signaling Mechanisms That Predict β-Cell Dysfunction in a Mouse Model of Type 2 Diabetes

“…In our previously published work [7], the fatty acids and fatty acid conjugates family was the most highly significantly expressed for both polar and nonpolar metabolites in plasma from obese mice [7]. Eicosanoids are highly bioactive fatty acid metabolites, and a subset of essential polyunsaturated fatty acids (PUFAs) provides the substrates for their synthesis [17,18]. Using the METLIN-annotated metabolic features shown in Supplemental Tables S3 and S4, the entire linoleic acid elongation and desaturation pathway was downregulated in NGOB vs. WT plasma: in most cases, with statistical significance (Fig- (E) glucose-stimulated insulin secretion from islets stimulated with 1.7 mM glucose or 16.7 mM glucose ±10 nM sulprostone.…”

Regulación de la respuesta inflamatoria de las células fagocíticas por lípidos: papel del ácido araquidónico y de los isómeros del ácido palmitoleico

“…El ácido araquidónico (5,8,11,14-ácido eicosatetraenoico, AA) es un ácido graso de la familia n-6 que se obtiene directamente de la dieta, o se sintetiza a partir del ácido linoleico (18:2n-6) mediante las acciones sucesivas de las Δ6desaturasa, elongasa y Δ5-desaturasa. Se produce principalmente en el hígado, pero también en otros tejidos (88,89).…”