Researchers find fats galore in human plasma

Human blood is famously fraught with fats; now researchers have a specific idea of just how numerous and diverse these lipids actually are. A national research team, led by scientists at the University of California, San Diego School of Medicine, has created the first ''lipidome'' of human plasma, identifying and quantifying almost 600 distinct fat species circulating in human blood.

''Everybody knows about blood lipids like cholesterol and triglycerides,'' says Edward A. Dennis, PhD, distinguished professor of pharmacology, chemistry and biochemistry at UC San Diego and principal investigator of LIPID MAPS, a US-wide consortium studying the structure and function of lipids. ''For the first time, we've identified and measured hundreds more and ultimately we might discover thousands.

These numbers and their remarkable diversity illustrate that lipids have key, specific functions, most of which we do not yet recognize or understand. This lipidome is a first step towards being able to investigate correlations between specific fat molecules and disease and developing new treatments.''

The findings will be published in the November issue of the Journal of Lipid Research.

In recent years, scientists have begun to appreciate the greater, more complex roles of lipids in human biology (among them the emergence of vitamin D). The utility of lipids in building cell membranes is well known, as is their function as repositories of stored energy. Less well-understood, however, is their role as signaling molecules.

''Fatty acids, which are common, are turning out to be very important communication conduits in some diseases,'' said co-author Oswald Quehenberger, PhD, professor of medicine at UC San Diego. ''For example, adipocytes (fat cells) use specific fatty molecules to communicate with distant tissues, a process that's been linked to insulin resistance and diabetes and may also involve inflammatory networks.''