Researchers found that knockout Nrf2 mice secreted more TNF-α, IL-1β, IL-6, and MMP9 via the NF-κB pathway in astrocytes than in controls (80).During the later stages of stroke, astrocytes also secrete factors, such as transforming growth factor-beta (TGF-β), that exert an active anti-inflammatory effect (81). This evidence concerns the gene MMP9 and Stroke.