Interplay Between Serum Bile Acids and Lipoproteins in the Postprandial Period: analysis of lipoprotein profile using NMR

• Grant number: 25/08547-6
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: July 28, 2025
• End date: November 27, 2025
• Field of knowledge: Biological Sciences - Biochemistry - Metabolism and Bioenergetics
• Principal Investigator: Jarlei Fiamoncini
• Grantee: Isabela Sinopoli Piccolo
• Supervisor: Lorraine Brennan
• Host Institution: Faculdade de Ciências Farmacêuticas (FCF). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: University College Dublin, Ireland
• Associated to the scholarship: 24/11650-0 - Oxidative Stress during the Posprandial Period in Women, BP.IC

Abstract

Lipoproteins are macromolecular complexes that mediate the transport of lipids through the bloodstream, playing a pivotal role in lipid metabolism. Postprandial lipid metabolism involves coordinated secretion and clearance of lipoproteins and their metabolizing enzymes. Bile acids (BA) are metabolites produced by the host and its intestinal microbiota. Due to the activation of nuclear and G protein-coupled receptors, these molecules influence lipoprotein, lipid and glucose metabolism. Particularly, the activation of Farnesoid X receptor by BA affects apolipoprotein expression and reverse cholesterol transport, impacting postprandial lipoprotein metabolism. Nuclear Magnetic Resonance (NMR) spectroscopy offers a powerful approach to analyze lipoprotein subclasses beyond conventional lipid measurements, providing a more detailed understanding of lipid metabolism. The aim of the study is to characterize postprandial lipoprotein profiles in females that exhibit distinct patterns of BA kinetics in plasma during a dietary challenge (ingestion of a high-fat, high-sugar meal) using NMR spectroscopy and their relationship with BA metabolism and postprandial kinetics. The study is composed of two phases: Phase 1 recruited 150 females for screening their postprandial BA kinetic during a dietary challenge (this phase has been recently completed); in Phase 2, 40 participants will be selected based on their postprandial plasma BA levels and will go through a second dietary challenge to sample blood (serum) at multiple time points up to six hours during the dietary challenge to quantify lipoproteins using NMR. These analyses will be carried out during the internship at Prof. Lorraine Brennan's laboratory at University College Dublin. The findings may advance our understanding of how lipoprotein dynamics in the postprandial state (which are known risk factors for cardiovascular diseases) are modulated by the postprandial kinetics of BA in plasma.