Soy Lecithin in High-Fat Diets Exerts Dual Effects on Adipose Tissue Versus Ileum.

SCOPE: Lipopolysaccharides and their transporters, LBP and sCD14, are involved in systemic inflammation following a high-fat diet. Natural emulsifiers such as soy lecithin, rich in soybean polar lipids (SPL), are often used by the food industry but little is known about effects of associating SPL with different oils. METHODS AND RESULTS: Thus, this study investigates the effects of 4 weeks feeding of palm (P) or rapeseed (R) oil-enriched diets with or without SPL in mice, on white adipose tissue (WAT) inflammation, on ileum permeability, and on microbiota composition. When SPL are associated with rapeseed oil, a greater gene expression of leptin and inflammation in WAT is observed compared to P-SPL. In ileum, R-SPL group results in a lower expression of TLR4, IAP that detoxify bacterial LPS and tight junction proteins than R group. In turn, the gene expression of Reg3ß and Reg3γ, which have antimicrobial activity, is higher in ileum of R-SPL group than in R group. SPL in rapeseed oil increases specific bacterial species belonging to Lachnospiraceae, Alistipes, and Bacteroidales. CONCLUSION: The incorporation of SPL in a diet with rapeseed oil exerts differential effect on WAT and ileum, with respectively an inflammation of WAT and an antimicrobial activity in ileum, associated with specific microbiota changes.

Bis(monoacylglycero)phosphate, a new lipid signature of endosome-derived extracellular vesicles.

Bis(monoacylglycero)phosphate (BMP), also known as lysobisphosphatidic acid (LBPA), is a phospholipid specifically enriched in the late endosome-lysosome compartment playing a crucial role for the fate of endocytosed components. Due to its presence in extracellular fluids during diseases associated with endolysosomal dysfunction, it is considered as a possible biomarker of disorders such as genetic lysosomal storage diseases and cationic amphiphilic drug-induced phospholipidosis. However, there is no true validation of this biomarker in human studies, nor a clear identification of the carrier of this endolysosome-specific lipid in biofluids. The present study demonstrates that in absence of any sign of renal failure, BMP, especially all docosahexaenoyl containing species, are significantly increased in the urine of patients treated with the antiarrhythmic drug amiodarone. Such urinary BMP increase could reflect a generalized drug-induced perturbation of the endolysosome compartment as observed in vitro with amiodarone-treated human macrophages. Noteworthy, BMP was associated with extracellular vesicles (EVs) isolated from human urines and extracellular medium of human embryonic kidney HEK293 cells and co-localizing with classical EV protein markers CD63 and ALIX. In the context of drug-induced endolysosomal dysfunction, increased BMP-rich EV release could be useful to remove excess of undigested material. This first human pilot study not only reveals BMP as a urinary biomarker of amiodarone-induced endolysosomal dysfunction, but also highlights its utility to prove the endosomal origin of EVs, also named as exosomes. This peculiar lipid already known as a canonical late endosome-lysosome marker, may be thus considered as a new lipid marker of urinary exosomes.