Also at the Select Biosciences meeting, John Shockcor, Ph.D., director of metabolic profiling business development at Waters, will discuss the impact of reverse-phase ultra performance liquid chromatography (UPLC) on the analysis of lipids from biological samples. Previously, normal-phase chromatography provided certain benefits but the long runs and poor resolution limited its utility for the study of lipids.
“UPLC has brought something that is revolutionary,” says Dr. Shockcor. “We can obtain sharper peaks and resolve large numbers of lipids with little overlap. One of the key features is that these runs are approximately 15 minutes and, in addition, the improved resolution and sensitivity allow a lot more to be performed with the same instrument.” Dr. Shockcor and collaborators have used this approach to collect structural information about specific lipids, which could not have been obtained with any other approaches.
This promises to improve our understanding of metabolic perturbations that occur during complex medical conditions such as diabetes and osteoporosis. While certain people appear to be perfectly healthy for a long time despite increased serum triglyceride or LDL levels, others develop heart disease much earlier and at lower concentrations, and the molecular basis of this phenomenon is insufficiently understood.
“The key to understanding these diseases is to gain a much better insight into lipid metabolism and especially into events that occur early during their progression,” says Dr. Shockcor. “We need to understand lipid biochemistry, and we cannot do that until we have the tools to understand what is going on in depth, within a reasonable time frame.”
Creating Metabolomics Databases
In other recent developments in the metabolomics arena, David S. Wishart, Ph.D., professor in the departments of computing science and biological sciences at University of Alberta, and collaborators have established a fully searchable human metabolome database that currently contains over 6,800 metabolites, ranging from the more abundant (>1 µM) to the more rare ones (<1 nM).
This represents the largest and most comprehensive organism-specific metabolomics database assembled to date and contains chemical, clinical, and molecular information about human metabolites and metabolic enzymes collected from urine, blood, and cerebrospinal fluid samples, according to Dr. Wishart. “The ultimate goal is to identify and quantify as many of the metabolites as we could find,” he adds.
Investigators in Dr. Wishart’s group previously characterized the cerebrospinal fluid metabolome and are currently focusing on establishing a database of metabolites exclusively found in the human serum. The comprehensive inventory of these body fluids provides a valuable resource for investigators from various fields such as biology, medicine, and environmental and plant sciences, who will be able to use the composition lists during their own work.
MetaboAnalyst, a web-based tool developed in Dr. Wishart’s lab, offers several options for data processing and statistical analyses during high-throughput metabolomic studies. “We want to be able to identify the metabolites that we are seeing and to give absolute concentrations. This represents a central challenge and also the key to making metabolomics a true omics science,” explains Dr. Wishart.