Hormonal Therapy For Alzheimer’s

.
Alzheimer's Donation
Donate Online Now
.
Researchers tested the theory of a testosterone link to Alzheimer's on mice. One group of mice could not produce testosterone. "Mice with low testosterone showed rapid progression in the development of Alzheimer's disease," said Dr. Pike. "That suggests -- if you dare to extrapolate what's going on in mice might be going on in aged men -- is that in the absence of testosterone, the brain becomes a much more willing environment for the progression of the disease."

Scientists gave another group of mice extra testosterone. These mice didn't have as much beta amyloid brain plaques -- characteristic of Alzheimer's disease -- as other mice. The testosterone mice also had less memory impairment.

Using a mouse model of AD, in which three genes had been altered, researchers evaluated how experimental manipulation of sex hormones affected the progress of the disease. Researchers removed the testes of young adult male mice and over several months, treated some with a testosterone hormone and others with a placebo.

After the treatment period, memory-related behavior and measures of Alzheimer-like pathology were measured in the different groups of mice. The castrated models that received the placebo showed poor working memory and high brain levels of Aâ. However, both Aâ accumulation and cognitive decline were prevented in mice treated with the hormone therapy.

“Although the results of the study predict that androgen therapy has the potential to reduce the risk of AD in at least some men,” Pike said, “clinical studies will be required to determine when and how to use androgen therapy.”

Before anyone starts taking testosterone boosters, Dr. Pike says it's too soon to assume the hormone would be a good way for humans to ward off Alzheimer's disease.

"There's all this great promise of what testosterone might be able to do in men. The problem is, we don't know what the long-term efficacy is. We don't know what the safety is," said Dr. Pike. "We jumped ahead with this with women and estrogen-based hormone therapy and it's gotten us into a bit of a mess. There was increased risk for breast cancer and increased risk for stroke." Studies have linked testosterone to prostate cancer.

However, the new data does extend the body of knowledge scientists have on Alzheimer's. Dr. Pike said previous population data has suggested the link between testosterone and Alzheimer's that this study confirms. "This at least gives you the ability to have a screening tool to identify aging men who are going to benefit from any type of potential preventive therapies," he said. The information could also help scientists create testosterone-like drugs that would target the cause of Alzheimer's and not affect other conditions, like prostate cancer.