Building upon the above discoveries, our research sought to answer the following issues: (1) Are the cerebral microvasculopathy observed in the GK rat and db/db mice present in HFD/STZ-treated model of T2DM rats; (2) whether the Jagged1-Notch1 pathway is involved in the impaired baseline cerebral neovascularization and angiogenesis both before and after diabetic cerebral ischemia, by which brain injury is aggravated. The gene discussed is NOTCH1; the disease is type 2 diabetes mellitus.