McEwen Investigators are finding new approaches using cutting-edge technology that could be applied to help repair damaged heart tissue. A sample of current research is listed below:
Increasing the regenerative capacity of the heart
Shortly after birth, heart cells stop dividing – this may be an important factor limiting the capacity of the heart to regenerate following injury. Dr. Rudiger von Harsdorf is studying the molecular mechanisms involved in the regulation of cell division in heart cells. Their objective is to improve heart function by stimulating the proliferation of healthy heart cells which may substitute lost or damaged heart tissue.
Cellular therapy
Dr. Keller’s research uses both mouse and human embryonic stem cells to study how the different cell types found in the heart develop. One the long-term objectives of this research is to be able to efficiently direct the development of embryonic stem cells to the heart cell lineage, ultimately providing a new source of heart cells for transplantation.
Research from Dr. Ren-Ke Li and Dr. Richard Weisel has shown that a number of different cell types can be implanted into the heart to improve cardiac function following a heart attack – and that the survival of these cells in the heart and their ability to improve heart function can be enhanced by transfecting the cells with genes prior to their transplantation into the heart. They are now determining which cell types, gene enhancements and delivery techniques are most effective to restore function in the damaged heart.
Dr. Mansoor Husain’s group is characterizing and optimizing an in vitro system for the differentiation of fully functional smooth muscle cells and heart cells from embryonic stem cells, with the objective of employing these cells in regenerative therapies.
Dr. Peter Zandstra is interested in how signals between and amongst cells can be controlled to guide the development of heart tissue. His group is developing innovative bioprocesses for the production of defined populations of embryonic stem cell – derived cells for cardiac cell therapies.
Tissue engineering
Using cells grown into three-dimensional biodegradable scaffolds, Dr. Ren-Ke Li and Dr. Richard Weisel are developing “patches” which could be employed as “replacement parts” during surgical repair to restore the normal size and shape of the heart after a heart attack. They are also investigating the use of these patches to repair malformed heart and blood vessels in children with congenital heart defects.
Drs. Li and Weisel have demonstrated that the bioengineered mesh seeded with heart cells beats regularly and spontaneously in a petri dish—mimicking the activity of the heart. These patches have been used to replace damaged portions of the heart and they function well.
Click below to view a video of beating heart cells.
Credit: Keller Lab
Figure: Biomaterials (top) are used to produce a cell-engineered tissue patch (bottom) to repair portions of the heart damaged by a heart attack in experimental models. Credit: Li/Weisel labs.
Background: What is Heart Disease?
Diseases of the heart and cardiovascular system are considered the leading cause of mortality and morbidity in the world and are known to have a profound impact on the quality of life of patients—affecting both children (congenital heart diseases) and adults (heart attacks, heart failure, stroke).
Heart disease encompasses a number of processes including heart attacks (the blockage of a blood vessel), heart failure (inadequate blood flow to vital organs) and other disorders which limit heart function.
Impact of Cardiovascular Disease
17 million men and women worldwide die each year from cardiovascular diseases (World Health Organization)
29.2% of total global deaths are attributed to cardiovascular disease
74,626 Canadians died as a result of cardiovascular disease in 2002 – over a third of all deaths in the country
$18 billion is the estimated overall annual cost of cardiovascular diseases in Canada alone (Health Canada: The Economic Burden of Illness in Canada, 1998)
Current Therapies for the Treatment of Heart Disease
