Scientists recycle fat into "liquid gold"

By Sheilah Downey - sheilahd at foodconsumer dot org

Using liposection leftovers, scientists at Stanford University have found a way to transform globs of gluttonous fat into useful stem cells that may regenerate tissues.

"We've identified a great natural resource," said Stanford co-author Dr.  Michael Longaker, who refers to the fatty leftovers as "liquid gold," according to a news release.

The human fat removed from patients during liposuction hide versatile cells that can be coaxed into induced pluripotent stem cells, or iPS cells, said scientists. The iPS cells are the ones used for research.

By reprogramming the adult cells to function like embryonic cells, say researchers, they can create cells lines to regenerate tissue or study specific diseases in the laboratory.

Recycling for science

As an added bonus, said scientists, they have found a way to recycle a rapidly growing natural resource.

"Thirty to 40 percent of adults in this country are obese," said Dr. Joseph Wu, senior author and cardiologist at Stanford. "Not only can we start with a lot of cells, we can reprogram them much more efficiently."

Wu said that while skin cells must be grown in the lab for three weeks before they are ready to use, the fat stem cells are "ready to go right away."

Another advantage to using the iPS cells, in addition to the fact that they aren't embryonic, is they are not derived from feeder cells taken from mice. Scientists worry that feeder cells, often used for growing human skin cells outside the body, can cause cross-species contamination.

The cells taken from fat have a pre-existing flexibility, said scientists, and can easily morph into bone, fat, or muscle as needed for research.

"These cells are not as far along on the differentiation pathway, so they're easier to back up to an earlier state," said first author Dr. Ning Sun, who conducted the research. "They are more embryonic-like than fibroblasts (skin cells), which take more effort to reprogram."

Into the future

Researchers are now investigating whether the gene profiles of the fat stem cells may be reprogrammed more efficiently.

"The idea of reprogramming a cell from your body to become anything your body needs is very exciting," said Dr. Longaker. "The field now needs to move forward in ways that the Food and Drug Administration would approve -- with cells that can be efficiently reprogrammed without the risk of cross-contamination -- and Stanford is an ideal place for that to happen."

Another possible use of the fat stem cells, said Dr. Wu, is in the treatment of serious, often fatal, diseases.

"Imagine if we could isolate fat cells from a patient with some type of congenital cardiac disease," he said. "We could then differentiate them into cardiac cells, study how they respond to different drugs or stimuli and see how they compare to normal cells. This would be a great advance."

The study was published online in the Proceedings of the National Academy of Sciences.