Can Estrogen Help Promote Brain Repair?
Are you concerned about your blood sugar? If the answer is yes, you're not alone. In fact, after learning that one-third of Americans have prediabetes, it's probably wise for all of us to read up on blood sugar, how it works, and what we need to do to keep our levels healthy.
In recent years, scientists have established a strong connection between brain health and blood sugar. In fact, Alzheimer's disease is often referred to as type 3 diabetes and according to the Mayo Clinic News Network: "It's an accepted fact that people with type 2 diabetes have a higher risk of Alzheimer's disease."
And now, a new study published in Science Advances found that the popular diabetes drug metformin was able to promote brain repair in mice. According to the authors of the study, the drug does this by activating stem cells in the brain, which can help establish new brain cells and repair the specific areas of the brain that have been damaged.
The researchers also wanted to know if metformin could restore cognitive function. At first they didn't notice a positive link, but when they looked deeper, they realized that the drug affected women differently than men. As the lead author on the study, Cindi Morshead, said, "When we first looked at the data, we did not see the benefit of the metformin treatment...Then we noticed that adult females tended to do better than the males."
Apparently, estrogen—more specifically a type of estrogen called estradiol—enhances the stem cells' ability to respond to the drug. Meanwhile, testosterone—which is often called the "male sex hormone"—seemed to inhibit the process, explaining why the male mice didn't respond positively to the metformin treatment.
This result comes at an important time, as the scientific community reflects on the sex bias that exists in medical research. Historically, research studies were done only on men because it was thought that female sex hormones would skew results. As Morshead explains, "The thinking was that we're going to study males because everything you need to know is found in the male brain, and then the female brain just complicates things with hormones." But that thinking is not only "misguided and troublesome for advancing neurological health," as Morshead puts it, but it has caused clinical trials to fail and many women to be misdiagnosed or given useless treatments.
So what's next in the world of estrogen and brain health? The same group of scientists is working on a pilot study that will test the effects of metformin on brain repair and cognitive function in humans. They plan to increase the number of participants in the study to fully evaluate the way sex affects treatment outcomes.