We hypothesized that: (1) anesthesia and surgery would cause mitochondrial dysfunction and trigger the activation of NLRP3 inflammasome-caspase-1 dependent pyroptosis in the hippocampus in aged mice, thus contributing to PND pathogenesis; and (2) administration of elamipretide would protect against surgery-induced cognitive deficits by attenuating mitochondrial dysfunction and neuronal pyroptosis. The gene discussed is NLRP3; the disease is Cognitive impairment.