This is the VOA Special English HEALTH REPORT.
Last month the Vatican confirmed that Pope John Paul has Parkinson's disease, a disorder of the nervous system. The eighty-three-year-old leader of the Roman Catholic Church is one of millions of people in the world with Parkinson's. The disease does not kill. Instead, it slowly damages the ability to move.
Parkinson's disease affects an area of cells in the brain called the substantia nigra. The cells lose the ability to produce the chemical dopamine. The decrease in dopamine causes one or more signs of Parkinson's.
These include slowness of movement, shaking of an arm or leg, or severe difficulty in moving the arms and legs. Another symptom is difficulty walking and staying balanced. Other signs may include restricted or decreased movement of the face. People may swallow less often than normal. And they may have trouble forming words when they talk. Also, victims may feel extremely sad or worried.
The disease is named after a British doctor, James Parkinson. He first described it in eighteen-seventeen. But he did not know the cause. We still do not know today.
Medical research has developed treatments, however. One is the drug levadopa. It replaces the natural dopamine in the brain. Levadopa helps ease the signs of Parkinson's. But it does not prevent brain cell damage.
Another treatment is to place electrical devices in the brain. These devices target cells that cause unwanted body movements. The most serious danger of this treatment is the possibility of a stroke.
Another treatment possibility involves replacing damaged brain tissue. Early experiments used cells from embryos. However, these experiments caused debate among people who oppose the ending of unwanted pregnancies. President Bush blocked federal money for such research. Researchers have begun to work with genetically engineered cells, animal cells and cells from the human eye. All of these cells can be made to produce dopamine.
Other experiments involve the naturally produced growth factor G-D-N-F. Researchers in the United States have tested it on a small group of people with Parkinson's. The study found that dopamine levels increased in their brains, and arm and leg movement improved. Now the researchers are designing a larger study.
This VOA Special English HEALTH REPORT was written by Nancy Steinbach.