BDNF and brain ischemia: Take together, triptolide exerts neuroprotective effects on cerebral ischemia by the following mechanisms: 1) inhibiting NF-kB signaling pathway, involving inhibition of NF-kB/PUMA signaling pathway and inhibition of p38 MAPK/NF-kB signaling pathway, 2) enhancing autophagy, 3) inhibiting apoptosis by activating PI3K/AKT/mTOR signaling pathway, 4) upregulating BDNF-AKT signaling pathways, 5) exerting antioxidant effects by inhibiting Wnt/β-catenin signaling pathway, 6) inhibiting oligodendrocyte apoptosis by upregulating the phosphorylation of the Src/AKT/GSK 3β pathway.