MMP9 and type 1 diabetes mellitus: In this study, we have demonstrated that SLI treatment significantly increased the number of brain microvasculature and improved glucose uptake in cortex, hippocampus and penumbra in the T1DM + MCAO rats through multiple mechanisms of action, including decreasing the expression of RAGE, MMP9 and inflammatory factors (COX-2, TNF-α and ICAM-1), and increasing the expression of HQ-1, HQO-1 and Nrf-2 in T1DM + MCAO rat.