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Fat, that much-maligned substance the medical profession warns patients to reduce, may someday save lives by becoming healing stem cells.

Stanford researchers are turning liposuctioned fat into stem cells in what could be a breakthrough for creating cells for heart repair, diabetes treatment and a host of other uses.

"You can feel lighter and the cells have a use in the future," said Stanford cardiologist and researcher Dr. Joseph Wu, an author of a paper published online in the Sept. 7 Proceedings of the National Academy of Sciences.

The researchers are excited by the findings, not only for its curative potential but also because it helps sidestep the sticky ethical debate of using stem cells culled from discarded human embryos.

Thirty to 40 percent of American adults are obese, and that's mountains -- or mountain ranges -- more fat than needed from which to extract adipose (fat) stem cells.

Adipose stem cells are more easily and quickly coaxed into becoming "induced pluripotent stem cells" (iPS) -- the most flexible of stem cells -- than are skin cells, which were discovered to have similar properties in 2007.

The iPS cells can turn into organ-specific cells, capable of regenerating heart, lung, kidney, muscle and other types of specific-purpose cells.

Both skin- and fat-derived stem cells could replace the controversial use of embryonic stem cells, according to the researchers.

The findings were published by a team of researchers including Wu, an assistant professor of cardiology and radiology at Stanford University School of Medicine, and Dr. Michael Longaker, deputy director of Stanford's Stem Cell Biology and Regenerative Medicine Institute.

The typical liposuction procedure removes one to two liters of fat from a patient, but cells can be grown from just 300 cubic centimeters, Wu said.

That's roughly "the equivalent of a can of Diet Coke, which is 360 cc.," he said.

Fat cells offer several advantages over other types of stem cells. They are easier to reprogram into the differentiated cells and provide a 24-fold yield over that of skin-cell-derived product, he said.

The fat cells can grow into the new cells in less than half the time it takes to create the same product with skin cells, he said. Skin cells typically take two or more weeks to produce a quantity sufficient to start the reprogramming process, Wu said.

The new cells take two to three weeks to become pancreatic, cardiac and other types of differentiated cells. Skin cells, in comparison, take four to five weeks.

And mouse-derived "feeder cells" that are often used to grow skin cells outside the body also aren't necessary with fat cells, removing concern of cross-species incompatibility and contamination, Wu said.

Several hurdles still need to be overcome, Wu said. Stanford researchers are "trying to isolate a sub-population of cells that would be even easier to reprogram," he said.

And researchers are trying to create a "non-viral vector" to integrate the new cells into the body.

Currently, viruses are used to carry stem cells into the body, after some of their genetic material has been removed to make them non-infectious.

Researchers don't want the body's cells to be permanently altered with the viruses' genetic material, he said. The body could also attack the viral vector, destroying the stem cells, Wu said.

"The body sees the virus as a bad product and the immune system destroys it. But a non-viral technique could potentially avoid those problems, he said.

Getting such therapies approved is a long way off, but the future is tantalizing, he said.

"In the grand scheme, we could program for pancreatic islet cells," eliminating diabetes.

"That's everybody's dream," he said.