Sex Differences in Astrocyte Cell Death
Mingyue Liu, M.D., Ph.D. – Principal Investigator

Important differences in risk and outcome from stroke exist between men and women.  Evidence suggests that gender-specific mechanisms that lead to ischemic cell death or, alternatively, to neuroprotection from ischemic injury are due in part to effects of sex hormones.  It has not been clear, however, if male and female cells have inherently different susceptibility to ischemic stress independent of any effects from sex hormones. 

Our studies demonstrate for the first time that, in the absence of sex steroids, primary rodent gender-specific astrocytes respond differently to ischemic-like injury induced by oxygen-glucose deprivation, i.e., 50% fewer female cells died than male cells.  In the current project, we are investigating the role of P450 aromatase in this sex difference in astrocyte death.  P450 aromatase is an enzyme present in astrocytes that converts the male sex hormone testosterone in brain to the female hormone 17β-estradiol.  We hypothesize that female astrocytes are protected against ischemic cell death by higher expression and activity of P450 aromatase compared to male astrocytes.

This research is funded by a grant from the American Heart Association.