Researchers from the University of California Medical School have discovered a way of changing adult fat cells into smooth muscle that could one day be used to help repair or replace damaged tissue. The technique uses multipotent stem cells derived from adipose (fat) cells - smooth muscle cells have previously been derived from adult brain and bone marrow but acquiring stem cells from fat cells is much easier and most patients would have a plentiful supply readily available.
Smooth muscle is found in hollow organs such as the bladder, blood vessels and arteries. The team found that after treating the stem cells with a cocktail of growth factors the new cells expressed proteins specific to smooth muscle. They then tested the functionality of the cells using a new device that tracked movement of microbeads dispersed in collagen gel embedded in the cells. Associate Professor of Bioengineering Dr Benjamin Wu, whose team developed the new technology, said, 'We found that the cells did indeed function just like smooth muscle. The new device allowed us to evaluate drug-induced changes in the physical properties of smooth muscle at the cell level'.
Scientists have been looking for a source of smooth muscle cells that could be used to repair organs and could help treat heart disease, gastrointestinal diseases and bladder dysfunction. Transplants using cells derived from the patient's own body remove the need for anti-rejection drugs, and do not suffer from the same controversy as embryonic stem cells. Lead researcher Dr Larissa V. Rodriguez, Assistant Professor in the Department of Urology at the David Geffen School of Medicine at UCLA, confirmed that the transformation was reproducible by cloning an adipose stem cell and repeating the smooth muscle transformation on the cloned population of cells. 'We wanted to make sure it wasn't an isolated case or particular conditions in the cell cultures that allowed us to create or select out already existing smooth muscle cells', said Rodriguez, adding 'We are surprised and pleased with the results and are excited about future applications'. The research is published in the Proceedings of the National Academy of Sciences.