What Causes Parkinson Disease and Alzheimer’s?

Understanding the underlying causes of neurodegenerative diseases is essential to advancing treatment and improving lives. One question that is commonly asked is: What causes Parkinson disease and Alzheimer’s? These two conditions are among the most prevalent neurological disorders, but while they share some similarities, their causes differ significantly. This blog post will explore the origins of both Parkinson's disease and Alzheimer’s disease, offering insights for those affected or at risk.

Parkinson's Disease: A Breakdown in Dopamine Production
Parkinson’s disease is primarily caused by the gradual death of nerve cells in a part of the brain called the substantia nigra. These cells produce dopamine, a chemical messenger essential for coordinating movement. As these dopamine-producing neurons die off, the brain’s ability to control movement diminishes, resulting in hallmark symptoms such as tremors, stiffness, slowness of movement, and balance problems.

While the exact cause of this neuron loss is still unknown, researchers believe a combination of genetic and environmental factors plays a role. Certain gene mutations, like those in the LRRK2 or PARK7 genes, can increase the risk of developing Parkinson’s. Environmental exposures—such as pesticides, herbicides, and heavy metals—have also been linked to increased risk, particularly in people with a genetic predisposition.
​
Additionally, abnormal protein deposits known as Lewy bodies, composed mainly of alpha-synuclein, are commonly found in the brains of people with Parkinson’s, although their exact role remains under investigation.

Alzheimer’s Disease: Plaques, Tangles, and Brain Cell Death
Alzheimer’s disease, the most common form of dementia, is associated with memory loss, confusion, and cognitive decline. It is primarily caused by the buildup of two abnormal structures in the brain:

1. Beta-amyloid plaques: Sticky clusters of protein fragments that accumulate between nerve cells and disrupt communication.
2. Tau tangles: Twisted fibers of the tau protein that form inside brain cells and interfere with nutrient transport.

These changes lead to cell death, brain shrinkage, and loss of function over time. Like Parkinson’s, the causes of Alzheimer’s are complex and likely involve genetics, age-related changes, lifestyle factors, and environmental exposures.

Certain genes, such as APOE-e4, are known to increase Alzheimer’s risk. Cardiovascular health, chronic inflammation, and head injuries are also believed to contribute to disease development.


Hope and Support for Those Affected
While there is currently no cure for either disease, there is support, education, and community available through organizations like the Parkinson’s Association of Southwest Florida (PASWFL).
For over twenty-five years, PASWFL has provided effective programs and services that improve the quality of life, educate, enrich, and empower our Southwest Floridians touched by Parkinson’s disease and related neurological diseases. Each week, PASWFL offers more than 25 free programs and support groups for members with Parkinson’s and their care partners.
​
There are no fees associated with becoming a member, and you can find the membership application online at www.parkinsonassociationswfl.org.
To learn more, sign up for their newsletter — click here
It’s free to become a member — join here