Within the USA Parkinson’s affects around 500,000 people, this number is projected to keep climbing given the progressive aging of the population. NIH estimates the condition is diagnosed in about 50,000 people every year, and warn that prevalence of the neurodegenerative condition will increase unless new and improved treatments are designed, and there still is no cure.
Levodopa is most commonly used as therapy to stimulate dopamine production in certain neurons associated with motor skills situated in the nigrostriatal pathway, which connects neurons in the substantia nigra pars compacta with the dorsal striatum. However the drug has a wide range of side effects and in the long term benefits of such dopamine regulating drugs are limited, making it crucial for more effective strategies to repairing brain damage caused by Parkinson’s disease worldwide.
Dr. Henchcliffe and Professor Parmar explain if successful using stem cells as a source of transplantable dopamine producing nerve cells could revolutionize treatment and patient care, as a single surgery could potentially provide a transplant treatment that could last the patient’s lifespan, reducing and/or avoiding need for dopamine based medications.
Fetal cells were used some three decade ago in pioneering studies of transplanted stem cells to treat Parkinson’s; however ethical issues and a host of side effects including transplant rejection and dyskinesias resulted with the procedure. The technology has advanced to materials from which stem cells are derived now being different, such as using a patient’s own skin to collect pluripotent cells to reprogram directly into neuronal cells. Cells can now also be reprogrammed directly into the brain via injections of conversion genes instead of human skin cells; and stem cells can be derived from the patient’s own blood.
This is an exciting time in the field for stem cell therapy, first generation cells are being trialed, and new advances in biology and genetic engineering are moving to new generations that show promise for even better cells and therapies, says Parmar. Henchcliffe adds that right now they are just taking the first steps in using cell therapies in Parkinson’s disease.
There is still a long way to go in demonstrating how well stem cell based reparative therapies work, and understanding what, how, where, and to whom to deliver these cells; but recent strides in the technology is making it tempting to speculate that cell replacement may play increasing roles in alleviating at least motor symptoms and others in the years to come, according to the researchers.
