Parkinson’s disease is a disorder of brain leading to stiffness of muscles, tremors of hands at rest and gait disorders. With the progress of the disease, patients may also have mental and behavioral changes, sleep problems, depression, memory difficulties, and fatigue. The disease affects both genders. The usual age of onset is 60 years but may start before 50 as early onset disease. Symptoms usually develop slowly over many years. The progression of symptoms often varies from person to person due to the diversity of the disease.
Parkinson’s disease has four main symptoms:
1. Tremors (trembling) in hands, arms, legs, jaw, or head
2. Stiffness of the limbs and trunk
3. Slowness of movements resulting in small steps in walking (shuffling gait)
4. Impaired balance and coordination, which often leads to falls
Causes of Parkinson’s Disease: Parkinson’s disease occurs when “dopaminergic” nerve cells degenerate or die. These cells are in the area of brain called “substantia nigra”. These neurons produce an important neurotransmitter called dopamine. When the neurons die or become impaired, they produce less dopamine, which causes the movement problems of Parkinson’s.
People with Parkinson’s disease also have degeneration of the nerve endings which produce norepinephrine, which is the main neurotransmitter of the sympathetic nervous system. Norepinephrine controls many automatic functions of the body, such as heart rate and blood pressure. The loss of norepinephrine might help explain some of the non-movement features of Parkinson’s, such as fatigue, irregular blood pressure, decreased movement of food through the digestive tract, and sudden drop in blood pressure when a person stands up from a sitting or lying-down position.
Source of good information about Parkinson’s disease: Parkinson’s Foundation https://www.parkinson.org/
Following video explains causes of Parkinson’s disease at cellular level.