However, the interleukin-9 can improve neurological functional deficit scores and reduce the infarct area in the ischemic brain tissue of middle cerebral artery occlusion rats by reducing astrocyte-derived factors such as VEGF-A and matrix metalloproteinase-9 (MMP-9) induced by oxygen-glucose deprivation (OGD) [55]. Here, IL9 is linked to medical procedure.