Multimodal neuroimaging reveals neural correlates of aromatase availability in the female brain

• Background: Estrogens extend their influence beyond reproduction, having been associated with neural plasticity and therefore the potential to shape the brain. It is unknown if the availability of aromatase, which is responsible for local estrogen synthesis in the brain, is associated with neural morphology. Here the correlation between in vivo brain availability of aromatase, grey and white matter structure, and peripheral levels of estradiol in healthy, young women was investigated.Methods: [11C]cetrozole positron emission tomography was performed together with structural and diffusion magnetic resonance imaging to assess the availability of aromatase, grey and white matter volumes, cortical surface architecture and white matter microstructure, respectively. Bioavailable gonadal hormone levels were measured. Results: Aromatase availability was notably high in the thalamus, hypothalamus, and amygdala, positively correlating with the grey matter volume of these regions. Cortical thickness and gyrification of the prefrontal cortex, as well as white matter properties of the fornix, were associated with aromatase availability. This suggests the impact of estrogens on the grey matter areas to which high aromatase-expressing regions are connected, and projecting white matter tracts, all part of the limbic brain that is often involved in mental disorders. Brain aromatase availability did not correlate with peripheral bioavailable hormone levels, pointing to a unique role of brain-derived estrogens. Conclusions: These findings provide the first evidence of brain morphological characteristics being associated with aromatase availability, shedding light on the impact of estrogens on brain structure.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Neurovetenskaper (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Neurosciences (hsv//eng)

Nyckelord

aromatase

brain morphology

estrogen

MRI

PET

women

Publikations- och innehållstyp

vet (ämneskategori)

ovr (ämneskategori)