Klein and her team tested the effects of estrogen on the influenza A virus, which commonly affects many during flu season. The tests were performed on nasal cells, cells that are directly affected by the flu, collected from both sexes. Viruses are tiny organisms that are able to enter our cells and kill them after they replicate themselves. The copies can further infect more cells and create a chain reaction. However, the less the virus is able to make copies of itself, the less affected we are.
Image Source: Ralf Hiemisch
The cells were exposed to the virus and different forms of estrogen, such as estradiol, bisphenol A, and selective estrogen receptor modulators (SERMS). The results clearly showed that all three compounds reduced the flu virus in the female cells but failed to do so in male cells. This was due to the presence of estrogen beta receptors, which control the substances allowed to pass into the cell. As females have a higher expression of these receptors than males, more degrees of protection are conferred to the females than their counterparts.
Other studies already have shown that estrogen has a beneficial effect on controlling HIV, Ebola, and hepatitis viruses. However, this study directly incorporates the sex-specific effect of estrogens and identifies the receptor responsible for the anti-viral effects.
Even though estrogen seems to be a protective measure against flu viruses, the effect may be hard to see in pre-menopausal women due to their fluctuating levels of estrogen. However, it is the first step in understanding the biological mechanisms that protect us against viruses. It also means that women on birth control or receiving hormone therapies may be better protected during the flu season. So, all the more reason to get your flu vaccine!
Feature Image Source: Mojpe