Scientists find protein levels can reduce heart damage
Posted Nov 21 2008 4:29pm
Scientists hope to be able to limit the extent of damage caused by a heart attack: High levels of the protein ALDH2 has been found to restrict damage to the heart muscle usually caused by a lack of oxygen during a heart attack.
The enzyme had previously been identified as an essential component in breaking down alcohol in the body, but scientists from Stanford University Medical Centre have now discovered that elevating levels of ALDH2 causes a protective effect by removing free radical cells (which are responsible for the tissue damage).
The study revealed that increasing levels of the protein before a heart attack reduced the amount of dead heart tissues by 60%. Research leader, Dr Daria Mochly-Rosen said: “We’ve found a totally new pathway for reducing the damage caused by free-radicals, such as the damage that happens during a heart attack.”
The lack of oxygen experienced during a heart attack causes a clot that blocks blood flow to the heart. This results in a build up of toxins causing the surrounding tissue to die. This clotting effect is also a potential danger during coronary bypass surgery, during which time, blood flow is redirected to allow clarity during surgery.
The researchers said their findings also have implications for current treatments. The drug, nitroglycerin is prescribed to patients who need to have their arteries widened to improve blood flow. This drug is converted to its active form by ALDH2. However, prolonged use of the drug has been found to reduce levels of the enzyme, thereby reducing it’s protective quality. The research team were able to screen ALDH2 and identified the Alda-1 molecule, which effectively sustained enzyme levels during nitroglycerin treatment. This discovery is especially important for patients from East Asia who carry a mutated form of the ALDH2 enzyme.
The researchers now plan to investigate how the enzyme works in other animals. Hurley, director of the Centre for Structural Biology at the Indiana University School of Medicine said: “We need to make it more potent, so it binds better and has the same effect at lower concentrations, because with any drug, we always like to give the lowest dose possible”
The findings also have potential in the treatment of patients who appear to have a resistance to nitroglycerin, patients with Alzheimer’s and Parkinson’s disease, angina sufferers, as well as an operational drug during bypass surgery.
Judy O’Sullivan, a cardiac nurse at the British Heart Foundation, cautioned that although the use of the component has exciting potential for many patients, it will “take many years before this could be confirmed in humans and then several more years before it would lead to the development of drug treatment to be used in clinical practice.”