Can stem cell therapy really reverse or retard the aging process and cure a variety of cancers?
Stem cell therapy refers to the use of stem cells to treat, prevent, or reverse a disease or condition. The term stem cell, on the other hand, does not refer to a single cell type. It is the collective term for the cell types in the body that have the capability to multiply infinitely and transform into a variety of specialized cells. There are many types of stem cells and their capabilities differ.
At present, the list of diseases or conditions for which stem cell therapy has been shown to be beneficial is a very short one. It doesn’t include retardation of the aging process.
The origin and nature of stem cells
The trillions of cells that make up a human being originated from a single cell, the fertilized ovum, which resulted from the union of the father’s sperm cell and the mother’s egg cell. After it has formed, the fertilized ovum multiplies many times over to produce potential stem cells, very versatile cells that have the capability to transform to any type of body cell. To produce the various tissues and organs however, these cells need to differentiate (i.e. transform into more specialized cells) several times. Each time they differentiate, stem cells lose some of their versatility, until they finally get restricted to transforming into a single cell type only.
At birth, most of a person’s stem cells are still relatively versatile, they can still produce a variety cells. But as the person grows older, his/her stem cells gradually and progressively decrease in number and capability. In adults, the capability of most of the stem cells that persist is limited to the production of functional cells that have short lifespan and rapid turnover rates, very few, if any, potential stem cells remain.
Adult stem cells usually reside in the organs where the functional cells they are committed to replenish are located. For example, in the bone marrow, there are enough stem cells called hemopoietic stem cells that ensure the continuous production of blood cells. In organs where the functional cells are long-lived such as the brain and muscles, however, very few stem cells persist to adulthood. Thus, often, nerve cells and muscle cells (such as those in the heart) that are lost are replaced not by functional cells but by cells that form scar tissue.
Conditions where stem cell therapy works
Stem cell therapy consists of harvesting stem cells, culturing them in the laboratory to increase their number, and then infusing them to patients where they can replace damaged, injured, or dead cells in the various tissues and organs.
At present, the stem cells therapies that are being legally performed involve bone marrow stem cells only. These stem cells can definitely replenish bone marrow cells, but it is not known whether they can likewise give rise to functional cells in other tissues and organs. In any case, stem cell therapy using bone marrow stem cells has proven success in only a few conditions, notably dysfunctional bone marrow, multiple myeloma, and leukemias (cancers of the blood).
Stem cell therapies that are currently peddled, which supposedly delay or reverse the aging process or cure other forms of cancer, Parkinson’s disease, diabetes, heart attacks, and other conditions should be considered highly experimental and labeled “caveat emptor.” They are of doubtful benefit yet very expensive, no less than a million pesos per treatment.
source: Manila Bulletin
http://www.mb.com.ph/primer-on-stem-cells-and-stem-cell-therapy/