Heart’s Own Stem Cells Offer Hope for New Treatment of Heart Failure
Stem cells under a microscope. (Credit: Image courtesy of King’s College London)
Researchers at King’s College London have for the first time highlighted the natural regenerative capacity of a group of stem cells that reside in the heart. This new study shows that these cells are responsible for repairing and regenerating muscle tissue damaged by a heart attack which leads to heart 1) ___. The study, published August 15, 2013 in the journal Cell, shows that if the stem cells are eliminated, the heart is unable to repair after damage. If the cardiac 2) ___ cells are replaced the heart repairs itself, leading to complete cellular, anatomical and functional heart recovery, with the heart returning to normal and pumping at a regular rate. Also, if the cardiac stem cells are removed and re-injected, they naturally ‘home-in’ and repair the damaged heart, a discovery that could lead to less-invasive treatments and even early prevention of 3) ___ failure in the future.
The study, funded by the European Commission Seventh Framework Programme (FP7), set out to establish the role of cardiac stem cells (eCSCs) by first removing the cells from the hearts of rodents with heart failure. This stopped regeneration and recovery of the heart, demonstrating the intrinsic regenerative capacity of these cells for repairing the heart in response to heart failure.
Heart failure — when the heart is unable to pump 4) ___ around the body adequately — affects more than 750,000 people in the UK, causing breathlessness and impeding daily activities. Current treatments are aimed at treating the underlying causes, such as coronary heart disease, heart attack and blood pressure through lifestyle changes, medicines and in severe cases, surgery. These treatments are sometimes successful in preventing or delaying heart failure. However, once heart failure develops the only curative treatment is heart transplantation.
By revealing this robust homing mechanism, which causes cardiac stem cells to home-in and repair the heart’s damaged muscle, the findings could lead to less invasive treatments or even preventative measures aimed at maintaining or increasing the activity of the heart’s own cardiac stem 5) ___.
Dr Georgina Ellison, the first author of the paper and Professor Bernardo Nadal-Ginard, the study’s corresponding author, both from the Center of Human & Aerospace Physiological Sciences and the Center for Stem Cells and Regenerative Medicine at King’s, said: “In a healthy heart the quantity of cardiac stem cells is sufficient to repair muscle 6) ___ in the heart. However, in damaged hearts many of these cells cannot multiply or produce new muscle tissue. In these cases it could be possible to replace the damaged cardiac stem cells or add new ones by growing them in the laboratory and administering them intravenously.”
Dr Ellison added: “Understanding the role and potential of cardiac stems cells could pave the way for a variety of new ways to prevent and treat heart failure. These new approaches involve maintaining or increasing the activity of cardiac stem cells so that muscle tissue in the heart can be renewed with new heart cells, replacing old cells or those 7) ___ by wear and tear. The cardiac stem cells naturally home-in to the heart because the heart is their home — they know to go there. Current practices involve major operations such as injection through the heart’s muscle wall (intramyocardial) or coronary vessels (intracoronary). The homing mechanism shown by our research could lead to a less invasive treatment whereby cardiac stem cells are injected through a 8) ___ in the skin (intravenously).”
Professor Nadal-Ginard added: “Although an early study, our findings are very promising. Next steps include clinical trials, due to start early 2014, aimed at assessing the effectiveness of cardiac stem cells for preventing and treating heart failure in humans.”
New Way to Treat Chronic Kidney Disease and Heart Failure
Researchers at St. Michael’s Hospital in Toronto are using adult bone marrow stem cells as they investigate a completely new way of treating chronic kidney disease and heart failure in rats.
Dr. Darren Yuen and Dr. Richard Gilbert were the first to show, in 2010, that enriched stem cells improved heart and 9) ___ function in rats with both diseases. But they and other scientists wondered about the potential side effects of returning those cells to the body, such as forming tumors.
In a paper published online October 16, 2013, in the journal Stem Cells, Drs. Yuen and Gilbert said they have since found that enriched 10) ___ marrow stem cells secrete hormones in the petri dish that, if injected into rats, has the same positive impact as the stem cells. “We’ve shown that we can use these hormones, collected in the dish, to replicate the beneficial effects of the stem cells in treating animals with chronic kidney 11) ___ and heart failure,” said Dr. Yuen, a nephrologist. “In our view, this is a significant advance for stem cell therapies because it gets around having to inject stem cells.”
Dr. Yuen said they do not yet know what kind of hormone the cells are secreting. Identifying the hormone would be the first step toward the goal of developing a synthetic drug.
Chronic kidney disease is much more prevalent than was once believed, with recent estimates suggesting that up to 5% of the Canadian population may be affected. The number of people with CKD and end-stage renal failure is expected to rise as the population ages and more people develop Type 2 12) ___. People with kidney disease often develop heart disease, and many of them die from heart failure rather than kidney failure.
ANSWERS: 1) failure; 2) stem; 3) heart; 4) blood; 5) cells; 6) tissue; 7) damaged; 8) vein; 9) kidney; 10) bone; 11) disease; 12) diabetes
Source: ScienceDaily.com, Wikipedia, WebMD.com