Multi-Organ Contribution to the Metabolic Plasma Profile Using Hierarchical Modelling

Area of Science:

• Metabolomics
• Systems Biology
• Physiology

Background:

• Understanding the origin of plasma metabolites is crucial for diagnosing metabolic disorders.
• Previous studies have not fully elucidated the specific contributions of individual organs to the overall plasma metabolic profile.

Purpose of the Study:

• To identify organs contributing to plasma metabolite levels using hierarchical modeling.
• To elucidate the role of specific organs in metabolite absorption, transport, and excretion.

Main Methods:

• Hierarchical modeling applied to plasma and organ samples from mice.
• Gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) for sample analysis.
• Multivariate analysis including Principal Component Analysis (PCA) and Orthogonal Projections to Latent Structures (OPLS).

Main Results:

• Each organ exhibited a unique metabolic profile.
• The gut, kidney, and liver showed the most significant contributions to the plasma metabolic pattern.
• Demonstrated metabolite absorption in the gut, excretion of branched-chain amino acids (BCAAs) by kidneys, and fatty acid transport to muscles and liver.
• Identified lactic acid transport from the pancreas to plasma.

Conclusions:

• Hierarchical modeling is effective for identifying organ contributions to plasma metabolite profiles.
• The study provides insights into organ-specific metabolic functions and metabolite trafficking.
• This approach can aid in attributing unknown metabolites to their organ of origin.