Stem cell therapy is growing in popularity globally particularly for neurological disorders and neurodegenerative diseases like Parkinson’s disease. Clinics offering stem cell therapy are now accessible globally and with costant advancements in stem cell technology, there is significant hope that it will be the ‘magic bullet’ in the treatment of Parkinson’s disease. However, to date there is no reliable evidence to suggest that any available stem cell therapy can cure Parkinson’s disease. This, however, does not mean that stem cell therapy cannot offer some improvement in the condition.
An Overview of Stem Cell Therapy for Parkinson’s Disease
Stem cells are immature cells which differentiate into different cells in the body. It is most abundant in fetal life but small amounts of partially differentiated stem cells are available in various tissues even in adulthood. Some tissues have large amounts of stem cells, like the bone marrow with its hematopoietic stems cells, but these cells are partially differentiated already and therefore only capable of forming the necessary blood cells.
A recent procedure has been able to ‘wipe’ clean these partially differentiated stems cells to once again form ‘blank’ stem cells that can then be stimulated to differentiate into a cell types of choice. These cells are known as induced pluripotent stem cells (iPSC’s) and made waves in the medical science community in 2010. It holds much promise for a number of conditions, not only Parkinson’s disease.
Parkinson’s disease arises due to a progressive decrease in the number of dopamine-producing neurons (dopaminergic neurons) in the substantia nigra of the brain. The lower than normal levels of dopamine, a neurotransmitter, is responsible for the features of Parkinson’s disease. In a nutshell, stem cell therapy holds the hope that by differentiating ‘blank cells’ into dopamine-producing neurons, at least partially, and injecting it into the substantia nigra, more dopamine-producing neurons will be available. Read more on Would Stem Cell Therapy Be A Parkinson’s Cure?
Stem Cell Clinics for Parkinson’s Disease
One of the challenges with regards to induced pluripotent stem cells is controlling the ‘reprogramming’ of the cell to form the dopaminergic neurons and integrating it into the brain tissue. In experiments on lab rats it was seen that integrating these dopaminergic neurons could be achieved on the rat. The net result could be an improvement in the clinical symptoms of Parkinson’s disease. However, the efficacy on human subjects has to be ascertained by properly structured and controlled clinical trials.
Stem cell therapy is available at a number of clinics but the long term effects and potential complications have yet to be ascertained. Although many of clinics market these techniques quite aggressively, particularly on the internet, none can truly lay claim to ‘curing’ Parkinson’s disease. There are also the concerns that undifferentiated stem cells contained in the ‘mix’ may also be delivered into the brain tissue. These cells may have the potential to differentiate abnormally and grow rapidly and become tumors. The other factor to consider is that the exact pathogenic mechanism of Parkinson’s disease is still not clearly known. Therefore the very mechanism that can affect the naturally-occurring dopaminergic neurons may also affect the iPS dopaminergic neurons. Considering the cost factor of stem cell therapy, this can be an expensive procedure that may only offer short term results, if any.
This is not to say that the therapy offered by these clinics are not beneficial to some patients to some degree but it should not offer false hope. Most dedicated Parkinson disease organizations are critical of these clinics and the therapy on offer not because of the therapy itself, but rather in the manner that it is marketed and the sometimes blatant but often subtle promise of a cure.