SIRT1 and Cognitive impairment: In addition, in a rat model of AD with intracerebroventricular injection of streptozotocin (ICV-STZ) [60], the level of p-AMPK and SIRT1 activity were decreased and the level of phosphorylated tau was increased, while AMPK-specific activator prevented cognitive impairment through rescuing SIRT1 activity, downregulating tau hyperphosphorylation, and repairing mitochondrial function reflected by increased ATP levels, mitochondrial membrane potential, complex I activity, and SOD activity, as well as decreased ROS generation.