Nicotine Byproduct Prevents Memory Loss in Alzheimer's Mice
It appears nicotine may have a positive role in dementia. According to the results of a new study, a nicotine byproduct called cotinine was shown to prevent memory loss in a mouse model of Alzheimer’s disease.
Cotinine protects neurons and enhances memory
Cotinine, which is an anagram of “nicotine,” is a chemical the body produces from its metabolism of nicotine. This major nicotine byproduct is nontoxic, lasts longer in the body than does nicotine, and has been shown in previous studies to be safe when used to help relieve symptoms of tobacco withdrawal.
Other previous studies have suggested that people who smoke have a lower incidence of Alzheimer’s disease. The benefit observed in these studies has been attributed to nicotine, which in mouse studies has reportedly improved memory and reduced plaque, an indicator of the disease.
Given nicotine’s other known damaging effects and the positive traits associated with cotinine, a team composed of researchers from Bay Pines VA Healthcare System and the University of South Florida (USF) decided to evaluate the use of cotinine in mouse models of Alzheimer’s disease. The study involved administering cotinine daily to a group of young adult mice for five months while a control group of mice were not treated.
At the end of the five-month period, the cotinine-treated mice performed better on tasks that involved memory and thinking skills than did the untreated Alzheimer mice. In the area of spatial memory, long-term treatment with cotinine appeared to fully protect the mice, as their ability to perform on this test was the same as that of mice without dementia.
Examination of the brains of the Alzheimer’s mice that were treated with cotinine revealed a 26 percent reduction in amyloid plaque deposits. Cotinine also inhibited the accumulation of substances that lead up to the formation of senile plaques and stimulated Akt, a factor that boosts attention and memory and promotes the survival of brain cells.
According to Valentina Echeverria, PhD, a scientist at Bay Pines VA and an assistant professor of molecular medicine at USF Health, cotinine’s safety record and ability to act on several aspects of Alzheimer’s disease pathology make it “a very attractive potential therapy for Alzheimer’s disease.”
With the projected number of people with Alzheimer’s disease to reach more than 65 million by the year 2030, according to Alzheimer’s Disease International, treatments that may prevent or stop progression of the disease are desperately needed, as no such approach has yet been found.
The authors of this study suggest that the nicotine byproduct cotinine “may be useful in preventing cognitive deterioration when administered to individuals not yet exhibiting Alzheimer’s disease cognitive impairment or those with mild cognitive impairment at early stages of the disease.”