MMP9 and Stroke: HUCBCs increase the density of oligodendrocyte progenitors and oligodendrocytes, increase angiopoietin 1 (Ang-1), expression, and decrease the expression of ischaemic border zone (IBZ) RAGE, matrix metalloproteinase 9 (MMP-9), and toll-like receptor 4 (TLR4), suggesting that HUCBCs have a therapeutic effect on nerve repair in DM rats with stroke 119, 120.