Estrogen is a well-known compound, often associated with women. Although the hormone, a chemical messenger, is also present in men, estrogen is commonly linked to women because of the role it plays in the growth and development of female sexual characteristics and features. Aside from contributing to the sexual development of women, estrogen has a multitude of other roles including controlling the aspects of the menstrual cycle, altering the growth of breasts, and affecting bone growth. More recently, researchers at the University of Guelph in Canada have discovered the effect estrogen can have on memory.
Early science and research led to the discovery that the hippocampus, a particular region in the brain, is responsible for cognition and memory in many animals. Estrogen can target the hippocampus and in turn target pathways involved in memory. In one particular experiment, researchers delivered a dose of estradiol (an estrogen receptor agonist) to female mice. After 40 minutes, the researchers measured memory by recording their performance on short-term memory tasks such as object recognition. They discovered that the female mice performed significantly better in these memory tasks when given the dose of estrogen. However, when the dosage was applied to only the brain tissue rather than the animal model, no such increased activity occurred. The scientists predict that the reason for this is that the dosage of estrogen increases the connections between the various neurons, which are only excited when actual learning occurs. When injecting the estrogen into just the cells, there is no learning in progress and so this growth in connections is absent. However, in the mice models, the animals are participating in learning activities, and therefore, we see an expansion of connections.
Image Source: Fernando Da Cunha
This new discovery of the link between estrogen and memory in female mice opens the path to further research about this connection in humans. We can potentially use estrogen therapy to boost memory and cognition in women. Perhaps one day, we can match specific dosages of estrogen to individuals to target specific parts of their memory improvement and maybe even help slow down the development of Alzheimer’s in individuals.
Feature Image Source: Wesley Fryer