A team of University of British Columbia researchers has identified fat-producing cells that possess "dual-personalities" and may further the development of treatments for muscle diseases such as muscular dystrophy and fibrosis.
The team found a new type of fibro/adipogenic progenitors, or FAPs, that generate fatty fibrous tissues when transplanted into damaged muscles in mice. Progenitors are similar to stem cells in their capacity to differentiate, but are limited in the number of times they can divide.
The findings are published in the current issue of Nature Cell Biology.
"These cells are typically dormant in muscle tissues," says lead author Fabio Rossi, Canada Research Chair in Regenerative Medicine. "Once activated by damage, they produce signals that coordinate tissue regeneration and then disappear. That's the Dr. Jekyll side of FAPs.
"In chronic muscle diseases such as muscular dystrophy, however, FAPs persist and may be contributing to over-production of scar tissues, resulting in fibrosis. That's the Mr. Hyde side," says Rossi, associate professor in the Department of Medical Genetics and the Biomedical Research Centre.
Better understanding of the role of FAPs could help encourage their healthy function or repress their negative impact, the researchers say. In the long term, drugs targeting these cells may be useful in a range of diseases characterized by fibrosis ranging from cardiovascular to lung and kidney disease, to organ transplantation. In addition, the cells' ability to generate new fat tissue could be exploited to target metabolic disease.
The study was supported by funding from the Canadian Institutes of Health Research, the Michael Smith Foundation for Health Research and The Foundation for Cell Therapy. The Biomedical Research Centre is affiliated with the Vancouver Coastal Health Research Institute.
The UBC Faculty of Medicine provides innovative programs in the health and life sciences, teaching students at the undergraduate, graduate and postgraduate levels, and generates more than $200 million in research funding each year. In 2007/08, out of the total UBC research endeavour, 53 per cent, or $247 million, came from academic and clinical teams in the Faculty of Medicine. For more information, visit www.med.ubc.ca.
The Biomedical Research Centre is an interdisciplinary research centre with the goal to generate new knowledge about how the immune system and adult stem cells accomplish their vital tasks, and how disturbances in these processes result in disease. The aim is to translate this new knowledge into innovative treatments for chronic diseases like arthritis, Alzheimer's disease, asthma, diabetes, and cancer. www.brc.ubc.ca.
VCH Research Institute is the research body of Vancouver Coastal Health Authority. In academic partnership with UBC, the institute advances health research and innovation across B.C., Canada, and beyond. www.vchri.ca.
Journal
Nature Cell Biology