As part of the aging process, the heart grows larger and its walls thicken, often leading to a disease known as diastolic heart failure. The condition is the most common form of age-related heart failure and affects millions of Americans. At present, there is no known treatment; however, Harvard University researchers have discovered a protein that when injected into the blood of mice, is able to reverse aging in the heart within 30 days; thus, effectively turning old hearts young again. The findings were published in the journal Cell.
After many years of research, the investigators have identified a protein known as GDF-11. Because aging occurs more or less uniformly throughout the body, the researchers had long suspected that one specific factor essentially signals to all of the body’s tissues how they should function as a context of age. Study author Amy Wagers, a professor of stem cell and regenerative biology at Harvard University, and colleagues focused on the blood stream because the blood carries substances to all parts of the body; thus, it was a logical place to search. They found that GDF-11 was at a high level in the blood of young mice and low in the blood of old mice. This suggested that it might have an impact on aging.
After discovering the protein, the researchers decided to study the impact it had on cardiovascular aging. They injected GDF-11 into the blood streams of older mice in order to increase their GDF-11 levels to match the levels found in younger mice. After 30 days, they examined the hearts of the older mice, which had previously shown thickened walls similar to those in older humans. The researchers found that the thickening had reversed, and the hearts of the older mice now looked almost identical to those of the younger mice. Previous research has shown regenerative treatment through the use of stem cells in spinal and muscular-skeletal systems; however, the researchers were surprised to discover that a protein could have a regenerative effect on the heart.
Although their findings show much promise, the investigators estimate that four to five more years of testing and research still needs to be done before clinical trials could begin. However, they hope to one day use this discovery to help reverse cardiovascular aging in humans as well.
Heart failure is often classified as either systolic or diastolic. Systolic heart failure means that your heart muscle cannot pump, or eject, the blood out of the heart very well. Diastolic heart failure means that your heart’s pumping chamber does not fill up with blood. Both of these problems mean the heart is no longer able to pump enough blood out to the rest of your body, especially when you exercise or are active.
As the heart’s pumping action is lost, blood may back up in other areas of the body, producing congestion in the lungs, the liver, the gastrointestinal tract, and the arms and legs. As a result, there is a lack of oxygen and nutrition to organs, which damages them and reduces their ability to work properly. Perhaps the most common cause of heart failure is coronary artery disease, a narrowing of the small blood vessels that supply blood and oxygen to the heart. Heart failure can also occur when an illness or toxin weakens the heart muscle or changes the heart muscle structure. Such events are called cardiomyopathies. There are many different types of cardiomyopathy.
Other heart problems that may cause heart failure are:
Congenital heart disease
Heart valve disease
Some types of abnormal heart rhythms (arrhythmias)
Diseases such as emphysema, severe anemia, hyperthyroidism, or hypothyroidism, may cause or contribute to heart failure
Common symptoms are:
Shortness of breath with activity, or after lying down for a while
Cough
Swelling of feet and ankles
Swelling of the abdomen
Weight gain
Irregular or rapid pulse
Sensation of feeling the heart beat (palpitations)
Difficulty sleeping
Fatigue, weakness, faintness
Loss of appetite, indigestion
Other symptoms may include:
Decreased alertness or concentration
Decreased urine production
Nausea and vomiting
Need to urinate at night
Infants may sweat during feeding (or other activity).
Some patients with heart failure have no symptoms. In these people, the symptoms may develop only with these conditions:
Abnormal heart rhythm (arrhythmias)
Anemia
Hyperthyroidism
Infections with high fever
Kidney disease
