Estradiol hormone protects against hearing loss

The "female sex hormone" estradiol is present in both men and women, and is generated from testosterone in men by the protein aromatase.

Estradiol plays various roles in addition to its gender-specific ones, including having effects on the hearing (auditory) system.

In a new study, Barbara Canlon and colleagues at the Karolinska Institute in Stockholm, Sweden, investigated the role of estradiol-binding proteins, known as oestrogen receptors, in response to auditory damage by examining hearing loss recovery in mice with deficiencies in various estrogen receptors.

They found that mice deficient in only the estrogen receptor ER-beta had reduced recovery from auditory trauma, and that treatment with ER-beta-binding drugs protected mice from auditory damage.

Furthermore, not only was ER-beta found in the ears of both male and female mice, but levels of the nerve-protecting protein BDNF were reduced in mice that lacked either ER-beta or aromatase.

The authors therefore concluded that this identification of an auditory-protective role for the oestrogen receptor ER-beta may enable the development of new treatments for hearing loss.

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