Parkinson's diseaseIntroduction

Parkinson’s disease (PD) is a chronic progressive neurological disease that is linked to decreased dopamine production in the substantia nigra and is marked by tremor of resting muscles, rigidity, slowness of movement, impaired balance, and a shuffling gait.
- The American Heritage® Dictionary of the English Language, 2007.

It impairs the motor skills, speech, and other functions1. The neurons at greatest risk in PD are substantia nigra pars compacta (SNc) dopamine (DA) neurons.

There are a number of risk-modifying factors for PD. One is low uric acid levels in the blood2. Uric acid scavenges superoxide, peroxynitrite and hydroxyl radical3. The role of uric acid in neuroprotection was outlined in Kutzing and Firestein4. Its main function seems to be to assist in the removal of superoxide by preventing the degradation of superoxide dismutase5. Doing so helps prevent its reaction with NO, blocking the formation of peroxynitrite6. Peroxynitrite plays an important role in the pathogenesis of PD7 8.

Milk consumption is found to increase the risk of PD, with milk protein (largely casein) indicated as the most important component9. Several studies have found lower uric acid levels associated with milk drinking10 11. Uric acid acts as an antioxidant in the brain, where it could affect risk of PD12.

There is also evidence that vitamin D reduces the risk of PD.

Page last edited: 03 May 2011


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