Potential regulatory effects of stem cell exosomes on inflammatory response in ischemic stroke treatment

Figure 1 Pathological changes after stroke. Blood-brain barrier (BBB) disruption after stroke is permeable to leukocytes and blood proteins. Microglia are stimulated, and these activated microglia (M1), in turn, release tumor necrosis factor-α, interleukin (IL)-6, and IL-1β, which activate the nuclear factor kappa-B inflammatory response of reactive astrocytes (A1) and further amplify this effect. Exosomes can penetrate BBB, promote microglial M1 polarization to M2 and T cell activation, mediate lipocalin-2, sirtuin 1, methionine adenosyl transferase 2B, pyrin domain-containing protein, cysteinyl leukotriene receptor 2, and other signaling pathways to promote the release of anti-inflammatory cytokines IL-10, transforming growth factor-β, and IL-4. By BioRender.com. BBB: Blood-brain barrier; CysLT2: Cysteinyl leukotriene receptor 2; IL: Interleukin; LNC2: Lipocalin-2; MAT2B: Methionine adenosyl transferase 2B; NF-κB: Nuclear factor kappa-B; SIRT1: Sirtuin 1; TLRs: Pyrin domain-containing protein; TNF-α: Tumor necrosis factor-α.