Hadassah International

Parkinson’s: Hadassah’s Physicians Battle the Disease on Two Bold Fronts

2-Feb-2010

Prof. Benjamin Reubinoff, Director of

Hadassah’s Center for Human Embryonic

Stem Cell Research
Treating today’s Parkinson’s disease patients with the latest innovations like Deep Brain Stimulation, Hadassah’s physicians are simultaneously searching for a cure through world-leading stem cell research.

Parkinson’s disease, characterized by a brain malfunction which disrupts electrical signals to the body that govern balance and motor control, is caused by selective degeneration of a cluster of neurons. These neurons release dopamine, the neurotransmitter affecting locomotion. When the bulk of these cells (50 to 70 percent) are destroyed, Parkinson’s symptoms appear. The disease expresses itself especially through tremors and the freezing of muscles. As the disease progresses, the tremors begin to interfere with daily activities and drastically impact the quality of life for patients and their families.

Conventional drug therapies supplement the dwindling amounts of dopamine produced by the remaining neurons; however, dopamine replacement medications do not slow the rate of neuron loss and their beneficial effects decrease over time. In addition, many patients develop severe side effects to the medications, including psychosis. Transplantation of fetus-derived dopaminergic neurons can relieve Parkinson’s in some patients, but limited tissue supply is a major obstacle to widespread use.

Deep Brain Stimulation is the current state-of-the-art therapy for advanced Parkinson’s disease. It often yields dramatic symptomatic improvements and enables the patient to reduce his drug therapy. The technique involves implanting electrodes, which are connected to a pacemaker, into the subthalamic nucleus of the brain. As with a heart pacemaker, neurosurgeons calibrate the electrodes to compensate for the degree of debilitation-–in this case, the severity of the particular patient’s movement disorders.

Hadassah’s neurosurgeons are world leaders in the micro-recording technique which provides accurate, real-time physiological analyses during surgery.

A multidisciplinary team of specialists in neurology, neurosurgery, neuropsychology, neuroimmunology, neurobiology, biochemistry, and genetics, as well as a team of psychologists and social workers help patients and their families decide on the best treatment options and ways to navigate daily life.

Stem Cell Therapy offers the first real possibility of curing Parkinson’s disease through replenishing dying dopaminergic neurons. Human embryonic stem cells, which can proliferate indefinitely and mature into any cell type, could provide the means of creating an unlimited supply of human dopaminergic neurons for transplantation.

Hadassah researchers are world leaders in the development of human embryonic stem cell lines and in deriving neural cells from them. They were the first in the world to demonstrate that human embryonic stem cells can improve the functioning of a rat with Parkinson's disease.

More than three years ago, Hadassah’s research team, headed by Prof. Benjamin Reubinoff, Director of Hadassah’s Center for Human Embryonic Stem Cell Research at the Goldyne Savad Institute of Gene Therapy, and Prof. Tamir Ben-Hur, head of Hadassah's Department of Neurology, created cultures of primitive nerve cells from human embryonic stem cells and transplanted them into an area in the brain of a rat where there were no dopaminergic nerve cells. After three months it was clear that some of the transplanted human cells turned into dopaminergic nerve cells. Based on this discovery, the team has focused on causing a large number of neurons to proliferate, so that massive amounts can be transplanted. The goal is for these cells to replace the damaged neurons and cure the disease. When this effort is successful, the Hadassah team will examine the possibility of transplanting these specially cultivated human embryonic stem cells into Parkinson’s patients, so their bodies can produce dopamine, thereby eradicating the disease!