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. Here, JAG1 is linked to type 2 diabetes mellitus.