ATF5-Dependent GDF15 Expression Mediates Anesthesia-Induced Neuroprotection Against Stroke.

Perioperative stroke is a rare but serious complication with a rising incidence in aging populations. Although preclinical studies consistently demonstrate that anesthetics such as sevoflurane can induce neuroprotective preconditioning against ischemic injury, clinical results have remained inconclusive. In this study, it is demonstrated that sevoflurane-induced neuroprotection is associated with the upregulation of genes involved in the mitochondrial unfolded protein response (UPR(mt)) and mitochondrial bioenergetic metabolism. The findings emphasize the critical role of ATF5 (activating transcription factor-5) in mediating these protective effects. Sevoflurane preconditioning markedly increases ATF5 expression and its downstream target GDF15, a key regulator of mitochondrial homeostasis, in the cerebral cortex. However, this protective mechanism is not activated in the aged brain, suggesting that aging impairs the ability to mount a mitochondrial stress response. The results imply a need for age-specific strategies to reduce perioperative stroke risk, including approaches that target mitochondrial function in elderly patients.