24
Aug
Researchers Determine Mechanism of DDT Link to Alzheimer’s, Informing Potential Treatments
(Beyond Pesticides, August 24, 2022) New research is helping the medical community understand the mechanism through which exposure to the banned insecticide DDT increases risk of Alzheimer’s disease. Published in the journal Environmental Health Perspectives, a team of researchers from Florida International University and Rutgers used multiple models to demonstrate the effects of DDT on the production of toxic proteins in the brain. The constant stream of new health risks regarding a chemical banned decades ago underlines the importance of a precautionary approach to pesticide regulation, particularly as red flags are already being raised about the connection between widely used weed killers like glyphosate and neurodegenerative diseases like Alzheimer’s.
“The vast majority of research on the disease has been on genetics — and genetics are very important — but the genes that actually cause the disease are very rare,” says study coauthor Jason Richardson, PhD of Florida International University. “Environmental risk factors like exposure to DDT are modifiable. So, if we understand how DDT affects the brain, then perhaps we could target those mechanisms and help the people who have been highly exposed.” Previous research from Dr. Richardson found that DDT exposure increased risk of Alzheimer’s by four times.
Scientists used cultured cells, and employed certain lab-reared breeds of mice and flies to study the impact of DDT on the amyloid pathway. Amyloids are proteins widely considered to be a causative factor in the development of Alzheimer’s, as these proteins are sticky, they clump together and build up in the brain, causing plaques that impair proper functioning of brain cells. To study how DDT affected this pathway, scientists focused on sodium channels the brain uses to communicate. A variety of complex analytical methods, including real time quantitative polymerase chain reaction, multiplex assay, western immunoblotting and immunohistochemical approaches were employed to analyze the mechanisms through which DDT affects these channels.
Results show that DDT exposure significantly increased the production of amyloid precursor proteins. DDT does this by causing sodium channels to remain open, which led to increased production of amyloid-beta. This mechanism was confirmed through the use of a compound called tetrodotoxin (a toxic chemical found in the liver of certain amphibians and fish, perhaps best known for its associated risk with eating puffer fish sushi). The compound prevents the regular flow of sodium channels in the brain. When introduced into their models, scientists find that they can prevent the production of amyloid proteins. “We found that if we block sodium channels with the compound tetrodotoxin and then dose neurons with DDT, then they don’t increase the amyloid precursor protein and don’t secrete excess amyloid-beta,” Dr. Jason Richardson indicates. “This finding could potentially provide a roadmap to future therapies for people highly exposed to DDT.”
Dr. Richardson indicates that his team will begin to look into those potential therapies, noting that there are already a number of drugs on the market that act on sodium channels. “We are in the process of doing those studies to see if we can take an already FDA-approved drug and see if it reduces toxic amyloid accumulation,” he notes.
Once pesticides are introduced into the environment, there is little that humans can do to hasten their degradation. Many of the organochlorine insecticides like DDT are still found in throughout the world, traveling through atmospheric transport and deposition, to this day creating risks in far-flung regions like Alaska and arctic glaciers. These insecticides accumulate in fatty tissue, and are equally insidious once inside the human body, unlikely to ever be completely eliminated. The hazards posed by DDT have already been decades long, and its multi-generational impacts may be felt for centuries.
Yet, with this history and these hazards in mind, the U.S. Environmental Protection Agency permits the chemical industry to tweak chemistries and continue to produce new, novel poisons that are equally likely to cause harm to current and future generations. Beyond Pesticides has long called for an end to this pesticide treadmill. To make the case for a broadscale transition away from hazardous synthetic pesticides linked to Alzheimer’s and other neurodegenerative disorders, the organization maintains the Pesticide Induced Diseases Database (PIDD). PIDD regularly tracks new scientific findings on the dangers of pesticides, providing ample evidence of the need for a pesticide-free future.
All unattributed positions and opinions in this piece are those of Beyond Pesticides
Source: Florida International University, Environmental Health Perspectives
IT IS PAST TIME TO PUT AN END TO PESTICIDES THAT ARE HARMING NOT ONLY OUR ENVIRONEMENT BUT OU HEALTH AS WELL. I’M QUITE SURE THAT SCIENCE CAN FIND A BETTER WAY TO PROTECT OUR PRODUCE.
August 24th, 2022 at 10:56 pm