Newsroom

OTTAWA, August 20, 2002 - Researchers from the Ottawa Hospital Research Institute (OHRI) have discovered that a type of self-destructing cell activity, previously believed to only be detrimental, is in fact necessary for the proper formation of muscle tissue. The findings Dr. Lynn Megeney, Dr. Pasan Fernando and their laboratory team appear in the August 20 edition of the prestigious Proceedings of the National Academy of Sciences, USA.

In many disease conditions, such as stroke, heart failure and muscular dystrophy, affected cells go through an organized form of destruction or cell 'suicide', called apoptosis. This process is carried out by a group of killer proteins. As a result, to stop this self-destruction, therapies are being developed that block the activity of the killer proteins.

However, the laboratory team of Dr. Megeney has made the surprising discovery that one class of cell-killing proteins, called caspases, are actually vital to normal cellular function. Dr. Megeney and his colleague Dr. Pasan Fernando have demonstrated that the normal maturation process of muscle is critically dependent on the function of these 'killer' proteins. "While we cannot rule out the role that caspases play in inducing apoptosis, we know that they are capable of performing some very critical non-death roles, such as making muscle stem cells grow into mature muscle tissue," says Megeney, who is also Assistant Professor in the Departments of Medicine and Cellular and Molecular Medicine at the University of Ottawa.

Consequently, Drs. Megeney and Fernando agree that the implication of their findings may result in a significant rethinking of the way in which certain diseases are treated. "The idea that you can block the activity of these factors and halt the progress of a specific disease may still be valid in some cases. However, at the same time, this blocking action will likely impair a vital cellular function in another location," says Megeney. While the focus of the study was on the development of skeletal muscle cells, the findings may extend much further. In fact, the researchers believe that these factors may be 'rehabilitated killers' in many cell types, such as brain and heart cells. "We've also observed similar features in other vital cell types. This would suggest a more universal concept than we initially anticipated, which makes this very exciting indeed," says Dr. Fernando.

Dr. Megeney and his team are able to push the boundaries of discovery in molecular medicine thanks to support from the Canadian Foundation for Innovation, the Heart and Stroke Foundation of Canada, the Muscular Dystrophy Association (USA) and the Canadian Institutes of Health Research.

Dr. Ron Worton, CEO and Scientific Director of the OHRI, is enthusiastic about the study's findings. "The mandate of the OHRI is to advance our understanding of health and disease. This important study from Dr. Megeney and his talented group of researchers is helping us fulfill that mandate," said Dr. Worton.

The OHRI is the research arm of The Ottawa Hospital, and a major part of the University of Ottawa Faculty of Medicine and Faculty of Health Sciences. Its research programs are grouped into: Molecular Medicine, Cancer Therapeutics, Clinical Epidemiology, Diseases of Aging, Hormones, Growth and Development, Neuroscience, and Vision. With over 100 scientists, 225 students and 400 support staff, and $34 million in external funding, the OHRI is one of the fastest growing, and most respected hospital-based research institutes in Canada.

For enquiries about the contents of the study, please contact: Office of News and Public Information (ONPI) at (202) 334-2138

To request a follow-up interview with Drs. Megeney and/or Fernando, contact: Ron Vezina, Media Relations Officer, (613) 737-8460, e-mail: rvezina@ottawahospital.on.ca

Back to news