Greater hypothalamic microglial activation with aging in women as compared to men: potential relevance to sex and species differences in reproductive and biologic aging.

In rodents, hypothalamic inflammation plays a critical role in aging and age-related diseases. We used Positron Emission Tomography with a radiotracer sensitive to the TSPO molecule expressed by activated microglia to assess, for the first time, human hypothalamic inflammation. We found that women but not men showed age-correlated hypothalamic TSPO expression, and suggest this is relevant to understanding a stark sex difference in human aging, namely, that only women undergo menopause.