Myofibrillar protein-based matrices are associated with altered intestinal lipid handling and enterohepatic signalling in adolescent female mice.
TL;DR
A potential application of the MP matrix is indicated to reduce dietary lipid absorption by promoting bile acid binding and regulating intestinal and hepatic lipid-related gene expression.
Abstract
Dietary lipids are typically ingested within complex protein-lipid matrices, where the protein source serves as a primary determinant of lipid digestion and bioavailability. However, the role of myofibrillar proteins, which are major components of meat, in influencing lipid handling and systemic lipid metabolism remains unclear. In this study, we examined the effects of four dietary protein matrices, i.e., myofibrillar protein (MP), sarcoplasmic protein (SP), casein (CAS), and soy protein isolate (SPI) on lipid bioavailability and enterohepatic metabolism in adolescent female C57BL/6J mice. Adolescent female C57BL/6J mice received daily oral gavage of 0.2 mL protein-lipid matrices consisting of soybean oil and protein solution (1 : 1, v/v; 10 mg mL-1 protein) for 32 days. The MP-Oil group exhibited significantly higher fecal excretion of lipids and bile acids, alongside reduced serum total cholesterol and low-density lipoprotein cholesterol (LDL-C) levels compared to the other protein groups. The MP-Oil treatment was also associated with downregulation of intestinal genes involved in lipid uptake (Cd36, Fabp2), re-esterification (Mogat2, Dgat1), and chylomicron assembly (Mttp). In addition, Asbt, Ostα, Fxr, and Fgf15 were downregulated in the ileum but upregulated Cyp7a1 in the liver. These findings indicate a potential application of the MP matrix to reduce dietary lipid absorption by promoting bile acid binding and regulating intestinal and hepatic lipid-related gene expression.