Effects of MSC on NF-κB signaling pathway. Treatment with MSCs suppressed activation of the NF-κB signaling pathway 24 and 72 h after ICH. By Western blotting analysis, a basal level of IκB-α (A, B) was detected in the brain tissue from sham-operated rats, whereas in the PBS-treated rats, IκB-α levels were substantially reduced. MSC treatment prevented the degradation of IκB-α in the PBS-treated group. Phosphorylation of Ser536 (C, D) in the cytoplasm and phosphorylation of NF-κB p65 (E, F) levels in nuclear fractions were increased in the PBS-treated group when compared with the sham-operated group. MSC treatment significantly reduced the phosphorylation of p65 on Ser536 and NF-κB p65 levels. n = 6 in each time point per group. Data are presented as the mean ± SD. *P < 0.05; **P < 0.01. GAPDH, glyceraldehyde 3-phosphate dehydrogenase; MSCs, mesenchymal stem cells; NF-κB, nuclear factor-кB; PBS, phosphate-buffered saline.