We don't usually think of belly fat as a good thing. But that flab may contain enough stems cells to repair a damaged heart.
This week two research teams reported the results from clinical trials in which heart patients were treated with stems cells derived from their own fat.
Many scientists have great hopes for stem cells because of their ability to turn into every specialized cell in the body. In theory, at least, they could be used to fix diseased organs. But the work has been highly controversial because the best source of stem cells is human embryos.
So scientists have been trying to isolate a sufficient supply of stems cells from the tissues of adults. And, based on the new research released this week, it now appears that fat could be a viable option. The finding were presented in Chicago at the annual meeting of the American Heart Association.
In both trials, each patient underwent liposuction to remove belly fat – about enough to fill a can of pop. The fat was put though a special stem-cell extracting machine developed by Cytori Therapeutics, a California-based regenerative medicine company. The stem cells – numbering about 20 million – were then injected into the patient's damaged heart muscle.
One trial, led by Emerson Perin of the Texas Heart Institute in Houston, involved 27 patients who could barely function because they suffered from advanced heart disease.
The other trial, led by Henricus Duckers of Erasmus University Medical Center in Rotterdam, included 14 patients who had just experienced massive heart attacks.
The primary goal of the research was to test the safety of the procedure before progressing to larger trials. In each study, some of the patients received a placebo that lacked stem cells. Those who got the real treatment didn't suffer serious side effects and even showed signs of improved heart function.
In the case of the heart-attack patients, the amount of damaged, orscarred, heart muscle shrank substantially within six months of treatment.
So how do adult stem cells help repair an injured heart? Dr. Perin said they are not as versatile as embryonic stems cells which can morph into any tissue type. However, adult stem cells still assist the regenerative process in a wide variety of ways.
"They produce dozens of different proteins ... reacting with other tissues and make things grow," he said. For instance, some of them turn into new blood vessels that increase the supply of blood flowing to the oxygen-starved heart muscle.
He noted the regenerative stem cells are simply doing what comes naturally to them. But the medical procedure provides "a big boost" to the repair process by delivering a huge number of the cells to the site of injury.
Dr. Duckers is already making plans for a large international trial that will likely include Canadian medical centres in Toronto and Montreal. Working on the assumption that more is better, he hopes to inject damaged hearts with a greater number of stems cells than in the initial trials.