Repairing The Heart With Stem Cells
Ron Hansen
SCI:115
Prof: Johnson
07/25/14

Repairing the Heart with Stem Cells
Let us consider the biggest United States killer of all: heart disease. Almost five million people are affected by congestive heart failure, the loss or dysfunction of heart muscles due to the ineffective pumping of the heart (Bethesda, 2001). Harvard Women's Health Watch published an article titled, Repairing the Heart With Stem Cells, which discusses the issue of heart disease and the possibility of a solution in stem cell replacement (Repairing the Heart with Stem Cells, 2013). This article explains what happens during a heart attack and why people who have had a heart attack may face a lifetime of maintenance to help the heart continue to work efficiently and to prevent further damage to the heart. The article makes use of experimental field studies to illustrate the regenerative capabilities of stem cells, showing that as much as 50% of heart scar tissue improved in seventeen patients. According to the article, not all doctors have the same positive results. The reason for the varying results seems to be due to different approaches in procedures used to acquire the stem cells and then to apply them. Stem cells from bone marrow come from adults. Another approach to the acquisition of stem cells is by extracting stem cells from the patient and then reinserting them where needed. The article goes on to explain that because cell therapy is relatively new there are still many questions unanswered and the long term effects of stem cell transplant, although safe, is inconclusive. The article concludes by explaining that at the moment stem cell therapy is only available to candidates who desire to participate in a research trial experiment. The evidence that adult and embryonic stem cells have the ability to replace damaged heart muscle cells is a fascinating area of contemporary biology. We all have at least one loved one who struggles with some form of heart disease and may have even passed on due to a lack of a good solution to this health issue, therefore, sparking one’s interest in a potentially new solution. Three biological issues that can be inferred from the article and discussed include cell division, differentiation of cells and somatic cell nuclear transfer (SCNT).
A cell reproduces by dividing, producing offspring each with a complete set of chromosomes so that each new cell can function properly. This process of reproducing is essential for the replacement of damaged heart muscles (Starr/Evers/Starr, 2013, pp. 133-5). The challenge in repairing the heart is that to repair damaged heart tissue, it will require millions of cells for transplant purposes and many scientists are continuing to experiment to find solutions. Adult and embryonic stem cells are capable of replicating themselves through cell division, sometimes even after long periods of inactivity. When a stem cell divides, each daughter cell has the ability either to continue to function as a stem cell or to become a specialized cell with a specific function, such as a muscle cell, a red blood cell or a heart cell. Stem cells start out as unspecialized but through the process of differentiation the cell gains the ability to become specialized (Starr/Evers/Starr, 2013, p. 123). Differentiation -the ability of stem cells, which start out unspecialized, to become specialized when transplanted- is essential to the success of stem cell research (Starr/Evers/Starr, 2013, p. 108) Experiments done in mice proved transplanted stem cells “migrate to the damaged region of the heart’s ventricle where they multiplied and became specialized cells,” (Bethesda, 2001). The cells differentiated into several types of tissue appearing to be “cardiomyocytes”, a heart muscle cell used to pump blood out of the ventricle, which is needed for cardiac repair (Bethesda, 2001). Although the article mentioned taking stem cells from bone marrow donors or the patient’s own heart, there are still other methods involving somatic cell nuclear transfer that researchers are considering.
Somatic cell nuclear transfer (SCNT) is a technique some scientists are experimenting with in relation to heart muscle cell repair (Staff, 2013). SCNT extracts a nucleus from an unfertilized egg and replaces it with another nucleus from another nucleus from another cell (Starr/Evers/Starr, 2013, p. 108). Some scientists believe stem cells derived from this technique might be superior over those gained from fertilized eggs because theoretically the rejection rate should lower once transplanted back into the donor. To this point researchers have only been successful in species other than humans (Staff, 2013). Funding this program would be a worthwhile endeavor.
In conclusion, it is easy to see how this article in the Harvard Women's Health Watch and the topic could be of interest to anyone, including myself, who may be affected by heart disease. My dad suffers from heart disease, and my uncle passed at 50 due to a massive heart attack. Stem cells regularly divide to repair and replace worn out or damaged tissues. Stem cell therapy is new and is showing potential for a possible solution. The article does eventually explain that there are risks but also states that, for the most part, injecting stem cells is relatively safe, and the long-term benefits outweigh the risks (Repairing the Heart with Stem Cells, 2013).

References
Bethesda, M. (2001, June 17). Stem Cell Information. Retrieved from National institutes of Health: http://stemcells.nih.gov/info/scireport/pages/chapter9.aspx
Repairing the Heart with Stem Cells. (2013, March). Retrieved from Harvard Health Publications Harvard Medical School: 3. http://www.health.harvard.edu/newsletters/Harvard_Womens_Health_Watch/2013/March/repairing-the-heart-with-stem-cells
Staff, M. C. (2013, March 23). Stem cells: What they are and what they do. Retrieved from Test and Procedures Stem Cell Transplant: 2. http://www.mayoclinic.org/tests-procedures/stem-cell-transplant/in-depth/stem-cells/art-20048117?pg=2
Starr/Evers/Starr. (2013). Biology Today and Tomorrow without Physiology. Mason,Ohio: Cengage Learning.