High mobility group box 1 (HMGB 1 ) is a family member of the high mobility group. HMGB1 binds to cell surface specific receptor-receptor for advanced glycation end products (RAGE) and toll-like receptor 2 (TLR2), and thus it exhibits extensive biological activities. HMGB1 participates in pathophysiological processes including inflammatory response and regulation of blood-brain barrier permeability in central nervous system, arid it is closely correlated with the diseases such as ischemia stroke, Alzheimer's disease and gliocytoma.