Scientists at Wake Forest School of Medicine researched how hormones such as estrogen protect women from severe cases of COVID-19. Their study, published in the journal Current Hypertension Reports, revealed that the sex-specific hormone could play a role in modulating the ACE2 enzyme that has a critical role in how SARS-CoV-2, the virus that causes COVID-19, attaches to the cells in our bodies.

This could explain why ''the male gender is emerging as an additional risk factor for severe COVID-19 and worse outcomes, independent of age,'' wrote the study authors.

''We know that coronavirus affects the heart, and we know that estrogen is protective against cardiovascular disease in women, so the most likely explanation seemed to be hormonal differences,'' said lead author Dr. Leanne Groban, a leading researcher in sex differences and health. According to Ladders, estrogen lowers the amount of ACE2 enzymes in the heart thereby reducing the number of potential cellular receptors on which the virus can attach itself.

The researchers said that by lowering the levels of ACE2 in the heart, estrogen also reduces the severity of the disease in women. A 2016 study published in the American Journal of Physiology found that estrogen helped women fight the flu by inhibiting replication of the virus that resulted in fewer complications and less illness.

''We hope our review regarding the role of estrogenic hormones in ACE2 expression and regulation may help explain the gender difference in COVID-19 infection and outcomes, and serve as a guide for current treatment and the development of new therapies,'' Groban said, according to a news release issued by the Wake Forest Baptist Medical Center.