Amygdala-liver signaling orchestrates rapid glycemic responses to stress and drives stress-induced metabolic dysfunction

Behavioral adaptations to environmental threats are crucial for survival and necessitate rapid deployment of energy reserves. The amygdala coordinates behavioral adaptations to threats, but little is known about its involvement in underpinning metabolic adaptations. Here, we show that acute stress activates medial amygdala (MeA) neurons that innervate the ventromedial hypothalamus (MeAVMH neurons), which precipitates hyperglycemia and hypophagia. The glycemic actions of MeAVMH neurons occur independent of adrenal or pancreatic glucoregulatory hormones. Instead, using whole-body virus tracing, we identify a polysynaptic connection from MeA to the liver, which promotes the rapid synthesis of glucose by hepatic gluconeogenesis. Repeated stress exposure disrupts MeA control of blood glucose, resulting in diabetes-like dysregulation of glucose homeostasis. Our findings reveal a novel amygdala-liver axis that regulates rapid glycemic adaptations to stress and links recurrent stress to metabolic dysfunction. 12 sections (2 sections per mouse) of formalin-fixed & paraffin-embedded (FFPE) mouse brains with AAV hSyn-mCherry injection into the ventromedial hypothalamus.