Figure 1.

Metformin decreases the insulin resistance by multiple mechanisms and increases insulin sensitivity [18]. Reduction in level of Aβ and phosphorylation of Tau protein by reduction of BACE1 translation [67] and improving the glucose level by suppression of gluconeogenesis are the other beneficial effects of metformin treatment in neurodegenerative disorders such as AD [18]. Metformin also improves cognition by increasing synaptic activity [64,65,131], suppressing inflammation and decreasing oxidative stress [75]. In addition, metformin has neuroprotection and neurorestorative effects to increase memory, learning, and cognition in AD cases [101].