Fatty Acids in Membranes as Homeostatic, Metabolic and Nutritional Biomarkers: Recent Advancements in Analytics and Diagnostics

Abstract

Fatty acids, as structural components of membranes and inflammation/anti-inflammatory mediators, have well-known protective and regulatory effects. They are studied as biomarkers of pathological conditions, as well as saturated and unsaturated hydrophobic moieties in membrane phospholipids that contribute to homeostasis and physiological functions. Lifestyle, nutrition, metabolism and stress—with an excess of radical and oxidative processes—cause fatty acid changes that are examined in the human body using blood lipids. Fatty acid-based membrane lipidomics represents a powerful diagnostic tool for assessing the quantity and quality of fatty acid constituents and also for the follow-up of the membrane fatty acid remodeling that is associated with different physiological and pathological conditions. This review focuses on fatty acid biomarkers with two examples of recent lipidomic research and health applications: (i) monounsaturated fatty acids and the analytical challenge offered by hexadecenoic fatty acids (C16:1); and (ii) the cohort of 10 fatty acids in phospholipids of red blood cell membranes and its connections to metabolic and nutritional status in healthy and diseased subjects.

Occurrence and biological activity of palmitoleic acid isomers in phagocytic cells

“…For these experiments, we prepared fatty acid methyl esters of cellular fatty acids, which were then converted into DMDS derivatives. DMDS derivatization provides unambiguous analytical resolution of positional isomers because methyl sulfide substituents add to the two carbon atoms of the double bond, thus preventing isomerization (41). Figure 1 shows a GC/MS analysis of a mixture of four commercial 16:1 isomers, namely 16:1n-10, 16:1n-9, 16:1n-7, and palmitvaccenic acid (16:1n-5).…”

“…Originally described in human sebum and later in hairs and nails, 16:1n-10 was commonly thought not to be present anywhere else in the human body (15,49,50). However, 16:1n-10 has recently been identified in erythrocyte membranes (41). Thus, our identification in circulating human monocytes was certainly no surprise, although the low levels at which the fatty acid presents in monocytes and macrophages make it difficult to envision a biological role for it in innate immunity and inflammation.…”

A Case Study of Familiar Gastrointestinal Pathologies at Risk of Cancer. Early Detection of Degenerative Signals by Oxidative Stress Biomarkers

“…An aliquot (1ml) of each blood sample was used for the fatty acid analysis of erythrocyte membrane performed by the procedure described in [30 -32]. This procedure is effected by an automatism set up at Lipinutragen [31], a spin-off company of the National Council of Research (CNR) in Bologna (Italy), connected with the calculation of the membrane unbalance index. The membrane fatty acid cluster used in the analysis is made of ten cisfatty acids and two trans fatty acids [31].…”

A method to determine the double bond position in unsaturated fatty acids by solvent plasmatization using liquid chromatography-mass spectrometry

“…Fatty acids (FAs) are the central components of living organisms as they constitute biological membranes in the form of lipid, can be converted into physiologically active signal molecules (i.e. eicosanoids and lysophospholipids), and serve as energy sources (1)(2)(3). Their chemical biological activities and are considered to be important subjects for studying human health (2,4,5).…”