Our study has shown that Pin1 expression is downregulated in the hippocampus of mice with diabetic encephalopathy, leading to a decrease in the phosphorylation of IRS1, AKT, and GSK‐3β, which are downstream of the IR/IGF1R pathway, an increase in Tau phosphorylation and exacerbation of neuronal apoptosis, resulting in cognitive dysfunction. The gene discussed is MAPT; the disease is diabetic encephalopathy.