Parkinson’s disease
Parkinson’s disease is a progressive neurodegenerative disease that begins its damaging course in the brain many years before the onset of symptoms such as tremors, muscle stiffness, and slow movements.
Parkinson's disease (PD) belongs to a group of conditions called motor system disorders, which are the result of the loss of dopamine-producing brain cells, among other changes.
The four primary symptoms of PD are:
- tremor, or trembling in hands, arms, legs, jaw, and face
- rigidity, or stiffness of the limbs and trunk
- bradykinesia, or slowness of movement
- postural instability, or impaired balance and coordination
As these symptoms become more pronounced, patients may have difficulty walking, talking, or completing other simple tasks.
PD usually affects people over the age of 50. Early symptoms of PD are subtle and occur gradually. In some people the disease can progress more quickly.
As the disease progresses, the shaking, or tremor, which affects the majority of PD patients may begin to interfere with daily activities.
Other symptoms may include:
- depression & other emotional changes
- difficulty swallowing, chewing, & speaking
- urinary problems or constipation
- skin problems
- sleep disruptions
There are currently no blood or laboratory tests that have been proven to help in diagnosing sporadic PD. Therefore the diagnosis is based on medical history and a neurological examination. The disease can be difficult to diagnose accurately, and requires significant clinical expertise.
By 2030, the number of individuals with Parkinson’s is estimated to double to 9.3 million as a result of aging populations, but medications to prevent or delay onset of the disease are not available.
A new target for Parkinson’s therapy:
Researchers identify ‘power switch’ gene
In a new finding from Harvard-affiliated Brigham and Women’s Hospital, researchers identify a link between Parkinson’s disease onset and dysfunctional activity of energy genes in the brain and identify a potential therapeutic target — the PGC-1alpha gene — to reverse this energy gene failure.
Researchers are trying to show that PGC-1alpha can be used as a “power switch” to turn on the expression of the energy genes — which are deactivated in patients with Parkinson’s — in cell models of the disease. Targeting the PGC-1alpha gene may be a worthwhile endeavor.
Pharmaceutical companies are already working on therapeutics that activate the PGC-1alpha pathway for more widespread diseases such as diabetes. This may jump-start the development of new Parkinson’s medicines.
To identify the dysfunctional processes in brains and dopamine neurons of patients with Parkinson’s, the researchers are using an innovative systems biology approach. Instead of looking at individual genes separately, systems biology looks at groups of genes — or gene sets — that together program vital cellular functions.
Using this approach the international consortium of researchers scanned the activity of 522 gene sets in 410 tissue samples from deceased Parkinson’s patients. The research team was able to identify 10 gene sets that are associated with Parkinson’s disease. All 10 are responsible for cellular processes related to mitochondrial function and energy production.
The discovery of PGC-1alpha as a potential new therapeutic target for early intervention in Parkinson’s disease. New drugs can possibly be developed to slow or halt Parkinson’s disease. Such drugs should be given early on, before too many cerebral neurons have died.
[edited from ninds.nih.gov and news.harvard.edu/2010]
