Pesticides may directly cause Parkinson's disease

Pesticides may directly cause Parkinson's disease


(NaturalNews) Pesticide exposure may not just increase the risk of
Parkinson's disease, but may actually start a cascade of events that
directly cause the disease, according to a study conducted by
researchers from the University of California-Los Angeles (UCLA),
UC-Berkeley and the University of Southern California, and published in
the Proceedings of the National Academy of Sciences.

Parkinson's
disease is an incurable, degenerative neurological disease
characterized by symptoms such as tremor, rigidity and a dramatic
slowing of speech and movement. It is believed to be caused by the
destruction of neurons in the brain, particularly in the substantia
nigra region of the mid-brain. One of this region's functions is the
production of dopamine, which plays an important role in communication
between cells. By the time Parkinson's disease is detected, it is not
uncommon for more than 50 percent of the brain's dopamine-producing
neurons to have already been destroyed.

Although a small
percentage of Parkinson's cases appear to be due to inherited, genetic
causes, the vast majority of cases seem unlinked to genetics.

"As
a result, environmental factors almost certainly play an important role
in this disorder," co-author Arthur G. Fitzmaurice said. "Understanding
the relevant mechanisms - particularly what causes the selective loss
of dopaminergic neurons - may provide important clues to explain how the
disease develops."

Investigating the pesticide link

Over
the past several years, UCLA researchers have successively established a
link between exposure to various pesticides and Parkinson's disease,
including the common agricultural chemicals maneb, paraquat and ziram.
This link is seen among both farm workers and those living or working
near agricultural fields.

In the new study, the researchers sought to determine whether there might be a link between Parkinson's
and benomyl, a pesticide that was banned in the United States in 2001
after 30 years of use, after it was linked to cancer, brain defects,
liver tumors and reproductive damage.

The researchers confirmed
in a laboratory study that dopaminergic neurons were damaged or
destroyed upon exposure to benomyl. They then exposed zebrafish to the
chemical, confirming that it led to significant death among dopaminergic
neurons, but not among any other nerve cells. This destruction occurred
because benomyl blocked the action of an enzyme known as ALDH, which
normally interferes with the action of a naturally occurring brain toxin
called DOPAL. Without ALDH, DOPAL builds up and destroys the
dopaminergic cells.

The ultimate cause of Parkinson's?

The
findings surprised the researchers, because ALDH had never before been
linked to Parkinson's disease, which was believed instead to be caused
by a protein called a-synuclein. If the study's findings are correct,
ALDH disruption may turn out to be a cause of the disease even in people
who have not been exposed to pesticides.

"We've
known that in animal models and cell cultures, agricultural pesticides
trigger a neurodegenerative process that leads to Parkinson's," senior
author Jeff Bronstein said.

"Our work reinforces the hypothesis
that pesticides may be partially responsible, and the discovery of this
new pathway may be a new avenue for developing therapeutic drugs."

Source:-
http://www.naturalnews.com/039186_pesticides_Parkinsons_neurological_disease.html