Neuroestrogens likely contribute to appetite regulation

Although a woman's ovaries produce the most estrogen, various types of estrogen are also synthesized throughout different tissues in the body, including the brain's neurons. New research in The FEBS Journal indicates that such neuroestrogens help suppress appetite.

Knowing that the enzyme aromatase is important for the production of estrogens, investigators depleted or knocked out the gene encoding aromatase in mice, so that the animals were unable to synthesize estrogens in a systemic or body-wide manner. These mice demonstrated increased food intake and body weight compared with their aromatase-expressing counterparts. Restoring aromatase expression specifically in the brain reduced food intake and increased sensitivity to leptin, the "fullness" hormone, confirming that neuroestrogens can influence appetite.

To further investigate the role of neuroestrogens independently of ovarian estrogen involvement, the researchers removed the ovaries in female mice. The brain's hypothalamus (the central hub for appetite signals) in ovariectomized mice showed increased expression of the gene encoding aromatase, and these mice decreased their food intake.

"Our results imply that neuroestrogens likely contribute to appetite regulation and may be relevant for body weight reduction" the authors wrote.