Estrogen and the memory

This paper reflects the research and thoughts of a student at the time the paper was written for a course at Bryn Mawr College. Like other materials on Serendip, it is not intended to be "authoritative" but rather to help others further develop their own explorations. Web links were active as of the time the paper was posted but are not updated.

Contribute Thoughts | Search Serendip for Other Papers | Serendip Home Page

Biology 103
2000 First Web Report
On Serendip

Estrogen and the memory

Melissa Donimirski

Estrogens are widely known as the steroid primarily influential in women's development and reproductive functions. Estrogens are responsible for growth of the egg follicle, as well as development and maintenance of the uterus and the endometrium. Also, estrogens are also significant in the differences that mark the male versus the female body. This includes smaller, shorter bones, broader pelvis, higher percentage of body fat, and narrower shoulders (1). In short, estrogens are what make women, women. However, estrogens have been found to be present in the blood and urine of males. Estrogens have more uses than just womanly curves and reproduction. Although not fully understood, estrogens are present in the body due to far-reaching necessity in many different parts of the body including memory.

Alzheimer's Disease (AD) and dementia are two diseases characterized by serious memory loss, the cause of which has been shown to be related to lower estrogen production and therefore loss of brain neurons. AD affects around 4 million people in the United States a majority of them women who are either perimenopausal or postmenopausal. As previously noted, male production of testosterone and estrogen gradually decreases, as opposed to a woman's rather sudden menopause. However, a woman's final estrogen production rate may be significantly smaller than a male's, possibly resulting in a greater incidence in females (2). . In addition, a female's final estrogen production rate may be significantly smaller than a male's.

Estrogen loss and memory loss have been shown to be related in those suffering AD. Estrogen receptors have been found in several places throughout the brain including the hypothalamus, preoptic area, anterior pituitary, and most importantly, the hippocampus (4). The hippocampus is especially important because it has been shown to be involved in certain aspects of learning and memory (5) the degeneration of which are primary effects of Alzheimer's. The reasons for this degeneration are many-fold. According to one study, estrogen is associated with an increase in the release of certain brain chemicals which transmit information across the space between two nerve cells, in the brain (4). Therefore, when estrogen presence decreases or disappears, neural chemicals which previously were available in high quantities are no longer largely present causing a decrease in brain activity. A study of estrogen-treated rats tends to support this theory in that the treated rats had higher memory performances than did estrogen-deprived rats (4).

It appears that estrogen stimulates brain cell growth in the hypothalamus and hippocampus. Therefore, estrogen apparently plays a significant role in promoting brain activity in regions that are responsible for cognition. Further, estrogen appears to be related to the production of certain proteins, named amyloid precursor proteins(4). These proteins are possibly linked to deterioration of neurons which would then result in Alzheimer's (6). The conclusion of one study found that there is a decreased risk of dementia and AD among women who undergo estrogen treatment after menopause. This could mean that estrogen therapy for those whose levels of the hormone have significantly decreased is important in preventing AD (4).

It is important to note, despite the optimistic numbers, the research on estrogen treatment for AD and dementia have only begun and are still experimental. Further, related risk of breast and ovarian cancers due to an increased or prolonged exposure to high levels of estrogen could prove to be just as debilitating and life-threatening as AD should estrogen treatment be a cause of increased risk of breast cancer. However, despite these discouraging notes it appears that estrogen and its effects on the brain may lead to some very positive developments in the area of prevention and treatment for a currently incurable disease.

Estrogens are by and large responsible for female reproductive functions and female body development and maintenance. Males, although not sufferers of menopause may have their own version, 'andropause' which in turn may be a cause of some concern in the field of male's health. Estrogens appear to be important in the area of memory. The loss of estrogen may then be related to Alzheimer's Disease and dementia, diseases which plague the older population of the United States. Estrogen therapy may be a solution. Studies at this time remain inconclusive, however, the future for Alzheimer's patients appears to be bright.

WWW Sources

1)Estrogen by Encyclopeadia Britannica

2)http://www.sfn.org/briefings/estrogen.html

3) http://www.alz-nca.org/aboutalz

4) http://www.ama-assn.org/special/womh/library/readroom/vol_279/jma71032.htm

5) http://faculty.washington.edu/chudler/hippo.html

6) www.mededge.com/meddic.htm> [2000, Feb 25]

| Back to Biology 103 | Back to Biology | Back to Serendip |

Send us your comments at Serendip