More Brain Points

Alzheimer's Disease: Is it a Women's World?

Meharvan Singh came to speak with us during Neuroseminar on September 10th about the role of let-7i & how the inhibition of it causes progesterone producing effects while focusing mainly on a mouse model of ischemia. Progesterone is a very important hormone assigned the role of protecting the brain. In the research mentioned in Dr. Singh’s article he discusses how progesterone is a protective hormone that helps to counteract negative effects of stroke, & other traumatic & neurodegenerative neural diseases. Although it is a potent neuroprotectant and a promising therapeutic for stroke treatment, the underlying mechanisms for progesterone remain unclear. Singh's laboratory recently reported that brain-derived neurotrophic factor is critical for the mediation of progesterone's protective actions and that progesterone-induced BDNF release from cortical astrocytes is mediated by a membrane-associated progesterone receptor. It was also noted that just because one can make more BDNF in a cell does not mean that it is a good thing; BDNF needs to reach the receptors in order to enact a positive result. During his talk,

Dr. Singh discussed that a significantly greater number of women than men (trifold) have Alzheimer’s disease and suffer from strokes as their cognitive brain ages. He addressed how through his research he has found that one of the contributing factors may be because women, when going through menopause, see a drastic decrease in the production of estrogen and progesterone. The average age that a woman goes through menopause is 51 years old, while the average woman lives to be about 81 years of. From this knowledge, one can reason that women then spend about 1/3 of their life in an estrogen/progesterone-level deprived state. Because of this dramatic decrease, they no longer are receiving the same amount of protective effects on the brain as before menopause. Could this put certain tissue types at risk?

Dr. Singh touches on the fact that doctors and researchers prescribe hormone therapy to counter some of the harmful consequences of menopause, such as losses in bone density. While this is beneficial in one regard, other large studies have shown that this type of hormone therapy can also increase the risk of breast cancer. Significantly more research needs to be done on the topic in order to determine its effects on the human body and whether or not the risk is worth being taken. It is hard to know if such research will ever take place, however.

As Dr. Singh stated, many large pharmaceutical companies are opting to just back out financially assisting the research that the neuroscience field desperately needs simply because it is too costly with often little to show at the end of these extensive clinical studies. Due to this, even though the extensive research behind Dr. Singh’s early research on the inhibition of let-7i and its relationship to the production of progesterone & BDNF, it's too early to say if there will be any new drugs made or other therapies utilized as an apparatus for preventative health care for women. It's up to future scientist like us to keep the field funded and alive!

Works Cited

Nguyen, T., Su, C., & Singh, M. (2018). Inhibition enhances progesterone-induced functional recovery in a mouse model of ischemia. Proceedings of the National Academy of Sciences of the United States of America, 115(41), E9668-E9677.

University of Southern California. "Effects Of Progesterone On Alzheimer's Disease." ScienceDaily. ScienceDaily, 28 November 2007
.
http://www.healingtherapies.info/progesterone2.gif