Fatty acid-related modulations of membrane fluidity in cells: detection and implications

Abstract

Metabolic homeostasis of fatty acids is complex and well-regulated in all organisms. The biosynthesis of saturated fatty acids (SFA) in mammals provides substrates for b-oxidation and ATP production. Monounsaturated fatty acids (MUFA) are products of desaturases that introduce a methylene group in cis geometry in SFA. Polyunsaturated fatty acids (n-6 and n-3 PUFA) are products of elongation and desaturation of the essential linoleic acid and a-linolenic acid, respectively. The liver processes dietary fatty acids and exports them in lipoproteins for distribution and storage in peripheral tissues. The three types of fatty acids are integrated in membrane phospholipids and determine their biophysical properties and functions. This study was aimed at investigating effects of fatty acids on membrane biophysical properties under varying nutritional and pathological conditions, by integrating lipidomic analysis of membrane phospholipids with functional two-photon microscopy (fTPM) of cellular membranes. This approach was applied to two case studies: first, pancreatic beta-cells, to investigate hormetic and detrimental effects of lipids. Second, red blood cells extracted from a genetic mouse model defective in lipoproteins, to understand the role of lipids in hepatic diseases and metabolic syndrome and their effect on circulating cells.ARTICLE HISTORY

Hippocampal lipidome and transcriptome profile alterations triggered by acute exposure of mice to GSM 1800 MHz mobile phone radiation: An exploratory study

“…properties of membranes, as well as change of membrane protein and channel functioning (Maulucci et al, 2016), that could also be the case in our study following RF-EMR exposure.…”

“…Those experiments showed that PUFA consumption was not occurring, but instead a remodeling response of the phospholipid fatty acid moieties with an increase in unsaturated components was taking place. This response can be indicated as the “first” sensitization targeting tissue lipids with an increase in unsaturation index, known in its turn to increase fluidity and permeability properties of membranes, as well as change of membrane protein and channel functioning (Maulucci et al., ), that could also be the case in our study following RF‐EMR exposure.…”

Functional lipidomics in patients on home parenteral nutrition: Effect of lipid emulsions

“…The membrane fluidity index, represented by the SFA/MUFA ratio, was normal in all the HPN groups, with the OO-IVLE group showing the greatest membrane fluidity. The maintenance of physiological cell membrane fluidity is a prerequisite for proper membrane function because it has a pivotal role in modulating the activity of the membrane enzymes, receptors, channels and transporters[25]. The inflammatory index, (expressed by the n-6/n-3 PUFA ratio), and the cardiovascular index (represented by the sum of the n-3 PUFAs) showed better values in the SMOF-IVLE group, reflecting the replacement of n-6 PUFAs with n-3 PUFAs in the RBC membrane, in agreement with the higher n-3 and the lower n-6 contents of the SMOF-IVLE.…”

The Nootropic Drug Α-Glyceryl-Phosphoryl-Ethanolamine Exerts Neuroprotective Effects in Human Hippocampal Cells

“…Memory decline and the reduced learning abilities in the elderly are supposed to be the consequence of a decreased quantity of phospholipids (PLs) and/or PUFAs in the brain. Not surprisingly, the changes in the lipid composition of brain cells have been correlated with neurodegenerative disease onset [6,7] and the presence of unsaturated membranes has been linked to shorter life span in different animal species [8][9][10]. Since PLs can promote PUFA transport, external PLs can restore the physiological composition of brain cellular membranes and produce valuable therapeutic effects in brain aging [4,5,11,12].…”