Reciprocal interactions between inflammatory and estradiol signaling pathways in the injured brain

Injury to the vertebrate brain causes neuroinflammation. Brain injury also causes the induction of aromatase in reactive astrocytes in rodents and songbirds. Glial aromatization and consequent estradiol (E2) synthesis are neuroprotective following brain injury. This induction has dramatic effects on cell turnover by decreasing cell death and increasing neurogenesis. Surprisingly, the factor(s) regulating its induction are unknown. The current work aims to elucidate those mechanisms, and suggests a role of glial aromatization in limiting neuroinflammation. To explore this relationship, various techniques are used including qPCR, enzyme immunoassay, and immunocytochemistry. Taken together, these data provide new evidence of a bidirectional relationship of neuroimmune and neuroendocrine signaling.