Control of adipogenesis by oxylipins, GPCRs and PPARs

Abstract

Oxylipins are bioactive metabolites derived from the oxygenation of ω3 and ω6 polyunsaturated fatty acids, triggered essentially by cyclooxygenase and lipoxygenase activities. Oxylipins are involved in the development and function of adipose tissue and their productions are strictly related to diet quality and quantity. Oxylipins signal via cell surface membrane (G Protein-coupled receptors) and nuclear receptors (peroxisome proliferator-activated receptors), two pathways playing a pivotal role in adipocyte biology. In this review, we made an attempt to cover the available knowledge about synthesis and molecular function of oxylipins known to modulate adipogenesis, adipocyte function and phenotype conversion, with a focus on their interaction with peroxisome proliferator-activated nuclear receptor family.

Potential Impact of Nutrition on Immune System Recovery from Heavy Exertion: A Metabolomics Perspective

“…Lipids are essential for biological processes, are important components of signaling pathways, and are closely linked to disease processes. The role of lipid mediators in the pathogenesis of disease, particularly inflammation, is an active, new area of research endeavor [82,83,84,85]. …”

“…Most of the PUFA substrate is esterified within cell membrane phospholipids, but can be rapidly released in response to inflammatory or injury stimuli through the enzyme phospholipase A2 (PLA2) [83]. The released PUFAs are changed through both enzymatic and nonenzymatic activities to form oxygenated derivatives called oxylipins [76,83]. Oxylipins can be divided into eicosanoids (synthesized from C20 PUFAs such as arachidonic acid and EPA) and docosanoids (synthesized from C22 PUFAs such as DHA), and also include linoleic acid oxygenated derivatives such as the HODEs.…”

“…Arachidonic acid can be oxygenated by a variety of different enzymes, including lipoxygenases (LOX), cyclooxygenases (COX), and epoxygenases that are catalyzed by cytochrome P450s (CYP), and can be converted to a complex mixture of eicosanoid oxygenated products as a result of lipid peroxidation [76,83]. Figure 8 shows that lipid mediators can also be produced non-enzymatically by autoxidation or by reactive oxygen species (ROS) [84].…”

“…n -3-PUFAs (EPA, DHA) have multiple double bonds and are highly susceptible to oxidation (Figure 9). DHA can be oxidized enzymatically via COX, LOX, or CYP pathways, and nonenzymatically through ROS reactions [76,83]. Both oxidation mechanisms produce a large variety of docosanoid oxidative metabolites.…”

Impact of dietary ω3 polyunsaturated fatty acid supplementation on brown and brite adipocyte function

“…In vivo, brite adipocytes stem from progenitors or emerge by direct conversion of mature white adipocytes (22)(23)(24). Several studies have demonstrated the involvement of oxylipins in fat mass development through the modulation of white and brown/brite adipocyte differentiation and activity (25). Mice exposed to diets with high levels of ω6 PUFA during the perinatal period display progressive accumulation of body fat across generations (26).…”