Altered lineage commitment of bone marrow mesenchymal stem cells in idiopathic osteonecrosis of the femoral head

Figure 4 Nuclear factor kappa B pathway activation and target gene expression in mesenchymal stem cells from osteoarthritis and osteonecrosis of the femoral head. Data are presented as mean ± SEM. Statistical analysis was performed using Student’s t-test; P values are indicated. A: Schematic representation of nuclear factor kappa B signalling under inflammatory stimulation. Upon receptor activation, the inhibitor of nuclear factor kappa-B kinase complex phosphorylates the inhibitor of nuclear factor kappa B alpha, leading to its degradation and release of the nuclear factor kappa B p65/p50 dimer, which translocates to the nucleus and regulates the transcription of target genes such as IL6, NFKBIA, and TNFα; B: Relative mRNA expression levels of interleukin 6, tumor necrosis factor alpha, and nuclear factor kappa B inhibitor alpha in mesenchymal stem cells derived from osteoarthritis (n = 10) and osteonecrosis of the femoral head (n = 10) patients, measured by quantitative polymerase chain reaction. OA: Osteoarthritis; ONFH: Osteonecrosis of the femoral head; NF-κB: Nuclear factor kappa B; IκBα: Inhibitor of nuclear factor kappa-B alpha; IKK: Inhibitor of nuclear factor kappa-B kinase; NEMO: Nuclear factor kappa B essential modulator; IL6: Interleukin 6; NFKBIA: Nuclear factor kappa B inhibitor alpha; TNFα: Tumour necrosis factor alpha.