The complex (plasma) lipidome quantified

There are thousands of lipid species in our bodies that represent 6 categories, but we only usually hear about the subcategories of cholesterol and triglycerides.  We don’t yet understand how they are all altered in response to various nutrients, dietary and lifestyle patterns and so on.  Recent advancements have made it possible to analyze a large number of lipid species from work by the LIPID MAPS Consortium, which is:

LIPID Metabolites And Pathways Strategy (LIPID MAPS) is a multi-institutional effort created in 2003 to identify and quantitate, using a systems biology approach and sophisticated mass spectrometers, all of the major — and many minor — lipid species in mammalian cells, as well as to quantitate the changes in these species in response to perturbation.

The ultimate goal of our research is to better understand lipid metabolism and the active role lipids play in diabetes, stroke, cancer, arthritis, Alzheimer’s and other lipid-based diseases in order to facilitate development of more effective treatments.

Quehenberger et al. took on this challenge and reported the results in a paper here.  The plasma sample standard originally came from 100 subjects 40 to 50 years old, with an equal number of men and women and ethnicities that were proportional to the US population.

In total, 588 lipid species were quantified between the 6 categories of: fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, sterol lipids, and prenol lipids.  The number in each category, as well as simplified relationships were reported in their following figure:

Though there are still some limitations in accuracy with current methods, this is the first in efforts to establish profile references of the lipidome for healthy contexts to compare to diseased contexts or dietary challenges, etc.  Currently, only triglycerides and cholesterol are usually clinically assessed, and while we know a lot about how nutrition effects these, their causal roles in disease or as biomarkers are controversial.  Assessing the entire lipidome will help to better understand the role of lipids in disease and produce new drug candidates as well.

Reference

Quehenberger O, Armando AM, Brown AH, Milne SB, Myers DS, Merrill AH, Bandyopadhyay S, Jones KN, Kelly S, Shaner RL, Sullards CM, Wang E, Murphy RC, Barkley RM, Leiker TJ, Raetz CR, Guan Z, Laird GM, Six DA, Russell DW, McDonald JG, Subramaniam S, Fahy E, & Dennis EA (2010). Lipidomics reveals a remarkable diversity of lipids in human plasma. Journal of lipid research PMID: 20671299