As a lifelong non-smoker, it feels odd to write something positive about tobacco, however encouraging research is showing that the nicotine from tobacco could be the base for a compound that may prevent or cure Alzheimer's disease. That news is, indeed, positive.
A study led by researchers at Bay Pines VA Healthcare System and the University of South Florida, has found that, in mice models, a tobacco-derived compound called cotinine prevents memory loss in mice genetically altered to develop Alzheimer's disease. The study finds that cotinine reduces the brain plaques associated with this type of dementia.
An article on eurekalert.org titled "Tobacco-derived compound prevents memory loss in Alzheimer's disease mice," reports on findings published in a recent Journal of Alzheimer's Disease.
The article quotes Valentina Echeverria, PhD, a scientist at Bay Pines VA Healthcare System and an assistant professor of Molecular Medicine at USF Health, as saying, "We found a compound that protects neurons, prevents the progression of Alzheimer's disease pathology, enhances memory and has been shown to be safe."
Cotinine is a byproduct of nicotine metabolism. The article acknowledges that some studies have shown apparently beneficial effects of smoking when it came to incidences of Parkinson's disease and Alzheimer's disease. However, the serious health damage done by smoking is well documented, so even if nicotine, which was thought to be the reason for the beneficial effects, is helpful, smoking could hardly be recommended to people as a viable means to prevent Alzheimer's disease.
The Bay Pines research team used mice as a vehicle to study the effects of cotinine. They concluded, "Cotinine.... is nontoxic and longer lasting than nicotine. Furthermore, its safety has already been demonstrated in human trials evaluating cotinine's potential to relieve tobacco withdrawal symptoms."
In my opinion, the fact that cotinine has been proven safe for human use is enormous in that the studies should move forward more quickly than if it were still only known to be safe in studies done on mice.
Fear-induced anxiety and PTSD
Of exceptional interest to me is that the research team "is also studying the potential of the tobacco-derived compound to relieve fear-induced anxiety and help blunt traumatic memories in mouse models of post-traumatic stress disorder."
Think of the huge benefits of cotinine if tests continue to prove the compound safe and effective. Preventing and/or curing Alzheimer's disease is the pot of gold at the end of the Alzheimer's research rainbow. However, anyone who knows a person with Alzheimer's or other dementia, post-traumatic stress disorder, or fear-induced anxiety - which is common with Alzheimer's patients - should see the huge potential this compound could have.
While my dad didn't have Alzheimer's disease, he was thrown into severe dementia due to failed brain surgery. The surgery was intended to correct the effects of a World War II brain injury that were compounding with age. One of Dad's symptoms that grew worse, long before there was fluid buildup behind scar tissue, was anxiety.

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