Los Angeles: Scientists have turned fat cells into muscle cells in an experiment published in the Proceedings of the National Academy of Sciences.
The researchers said that although they would not be able to use the cells to turn fat tummies into flat ones the experiment showed how fat can be a source of master cells which could be used to repair organs. These cells are of a type that help the heart beat and blood flow, push food through the digestive system and make bladders fill and empty.
Assistant Professor Larissa Rodriguez from the Department of Urology at the University of Los Angeles medical school said the cells may prove a source to regenerate and repair damaged organs.
Rodriguez and colleagues incubated adipose-derived stem cells in a nourishing mixture of growth factors, human proteins that encouraged the cells to become smooth muscle cells.
The researchers said scientists have been looking for sources of smooth muscle for organ repair and treating heart disease, gastrointestinal diseases and bladder dysfunction. Previous studies that used cells from a patients own organ failed because the organ was damaged or diseased.
But transplants grown from a patient’s own fat could be used with no need for anti-rejection drugs. Smooth muscle cells have been produced from stem cells found in the brain and bone marrow, but acquiring stem cells from fat is much easier.
The stem cells found in fat are known as multipotent stem cells. They can produce a variety of cell and tissue types, but are not as flexible as embryonic stem cells.
Last week, President George W. Bush vetoed a bill that would have broadened federal funding of human embryonic stem cell research, saying he preferred that researchers pursue so-called adult stem cells, such as those used at UCLA.
Many groups have been looking to fat as a source of stem cells. In April, Cytori Therapeutics Inc. said it was starting a clinical trial to test whether stem cells derived from fat can be used to regenerate breast tissue.
Other researchers have been trying to get stem cells from liposuction specimens.
In a second study published in the same journal, British researchers said they found one important protein that keeps stem cells in a quiescent and non-dividing stage.
Fiona Watt of Cancer Research UK and colleagues studied stem cells from human skin and found a protein known as Lrig1 kept the skin cells from proliferating. When Lrig1 production was silenced, the stem cells began growing and dividing.
The finding may not only offer important information to stem cell researchers, but may also offer insights into cancer, Watt’s team said. In cancer, cells ignore the normal signals from the body and proliferate uncontrollably. The protein is also involved in psoriasis.