Tag: gene therapy

How Can Genes Contribute to and Cure Congestive Heart Failure?

How Can Genes Contribute to and Cure Congestive Heart Failure?

It is common knowledge that heart failure follows another severe form of heart damage; however, until now scientists and doctors have had no way to identify those at risk. New research into genes and gene therapy have made them a potential weapon in the fight against heart failure.
Scientists have made several discoveries regarding the role of genes in the detection and treatment of heart failure. Several years ago it was discovered that a small percentage of patients who had suffered heart failure possessed a defect in the gene that allows the body to detect stress signals; in essence, the heart does not know that it is working to hard and is unable to adjust. This percentage may seem insignificant; however, the gene mutation was not present in any of the healthy patients examined. Researchers stress that this is a susceptibility factor, not a cause of congestive heart failure; however, it may be the breaking point when determining if a heart suffering from other disease will fail. Detection of this mutation may allow doctors to identify and treat patients at risk prior to their heart failing rather than after.

This defect is found in the ATP-sensitive potassium channels and is caused by a genetic mutation. The potassium channel regulates potassium and calcium levels in the body. While the heart must have calcium to function, an excess of calcium leads to damage. This is the reason calcium blockers are often given to patients with congestive heart failure. Fortunately, medications to open the potassium channel already exist.

In addition, a defect of the delta-sarcoglycan gene has been seen in hamsters with muscular dystrophy and cardiomyopathy. This gene is the cytoskeleton of muscle fibers, and successful transplant of a normal human delta-sarcoglycan gene has been shown to cause a tremendous improvement in these animals. This is noteworthy because current transplant attempts require open heart surgery. This type of gene transplant is carried on a virus, eliminating the need for surgery.

Scientists had been a bit concerned with using this method of gene therapy due to the need for a systemic effect. There was also some concern that the body’s natural immune system would eliminate the virus of its own accord prior to successful delivery of the gene; however, they believe they have found the best form of virus to successfully slip past the body’s defenses. When transplanting the delta-sarcoglycan gene researchers used a type eight adeno-associated virus, piggybacking the corrective gene onto it as it was inserted into the body. This allowed the gene to be carried to all areas of the body in animals with muscular dystrophy without being destroyed by the body’s own natural immunity.

Gene therapy is still highly experimental, and researchers are unsure yet of the role it will play in the conquest of heart failure; however, this represents a technology that was unavailable thirty years ago. Continuing advancements in technology and medicine’s knowledge of the body’s building blocks may one day unlock the mysteries to the cure of this deadly disease.

What New Therapies for Treatment of Congestive Heart Failure?

Heart disease is one of the deadliest killers in the world to date. Congestive heart failure, a condition found secondary to many major cardiac diseases, possesses its own high mortality rate. Fifty percent of those diagnosed with congestive heart failure will die within the five following years. Scientists and researchers are struggling to understand the exact mechanisms of the disease, and to find a cure.

Congestive heart failure results as the cells in the heart die or become non-functioning due to an event such as a myocardial infarction (a heart attack) or ischemic heart disease. Whatever the cause, the heart is subsequently unable to pump blood adequately throughout the body, resulting in the blood pooling in the organs and fluid building up in and around the lungs as sodium is unable to be properly excreted, causing the dyspnea that is the classic symptom of congestive heart failure.

Clinical research is targeted at both the treatment of the disease and the possibility of repairing the damaged cells in the heart. Current research is underway to test new medications that would assist in vasodilation, as well as a calcium inhibitor that would not result in the higher incidence of cardiac arrhythmia seen with the medications currently on the market.

In the age of natural medicine, the power of the mind has been invoked in clinical trials to use meditation and relaxation techniques to combat the stress on the heart that can be the breaking point for patients with heart failure. Stress has been shown to negatively affect the body’s blood pressure, forcing the heart to work harder and placing an undue amount of pressure on an already weakened muscle. The theory lies in the belief that by learning to maintain a low level of mental stress the heart will be less stressed and therefore less likely to fail completely, and the patient can be given a better prognosis.

Alongside the return to natural, holistic methods of treatment is an incredible advancement in clinical technology that was not available twenty or thirty years ago. Scientists claim to have identified a set of altered genes that can make an individual more disposed to suffer from congestive heart failure and are using their current knowledge of genes and the benefits of gene therapy to attempt to reverse the effect. In addition, medications to tamp down on the genes’ activities, such as beta blockers and alpha-2 agonists are already available and being used in treatment programs.

Also being explored is the possibility of using stem cells, the body’s pluripotent progenitors, to assist in reparation of the damaged heart tissue. Clinical trials showed that patients suffering from congestive heart failure responded very favorably to an injection of their own stem cells into the heart, although the exact means by which this causes improvement is as yet unknown. It is suspected that these cells either facilitate the growth of new vessels in the heart or act as beacon, attracting the body’s own healing cells to the site of the damage and stimulating repair.

The possibility of actually growing healthy tissue from embryonic stem cells to be transplanted is also being explored, although the controversial nature of the use of embryonic stem cells due to the necessary destruction of the embryo makes this questionable in the foreseeable future. Scientists have determined that adult stem cells simply cannot provide an adequate number of new cells to meet the needs of patients who have suffered heart failure.

Heart failure is incredibly dangerous because the body cannot reproduce the dead tissue cells in the heart; however, with modern advancements it is the great hope of researchers everywhere to one day find a cure.