Figure 5.

Angiopoietin‐like protein 8 (ANGPTL8) promoted extracellular matrix (ECM) degradation and inflammation through NF‐κB signalling pathway in human NP cells. The human NP cells were treated with TNF‐α (50 ng/mL) except for the NC group. (A‐E), The mRNA expression level of ANGPTL8 (A), MMP3 (B), MMP9 (C), COL2A1 (D), IL‐6 (E) were measured respectively by qRT‐PCR in ANGPTL8 silencing or overexpression treated with BAY‐11‐7082 or not. (F‐H), ELISA kits were used to detect the secreted ANGPTL8 (F), MMP3 (G), MMP9 (H) respectively in different groups. (I), The components of IKK complex and the downstream phosphorylation level of IκBα and p65 were analysed by Western blot analysis. (J‐O), The relative protein level of ANGPTL8 (J), IKKα (K), IKKβ (L), IKKγ (M), phosphorylated IκBα (N) and p65 (O) were analysed by the protein quantification. GAPDH was used as an internal control. Data were presented as the mean ± SD (n = 3). *P < 0.05 vs NC group, ^# P < 0.05 vs TNF‐α group. (P), Representative images of ANGPTL8, MMP3, MMP9, COL2A1 and IL‐6 protein expression were showed by immunofluorescence staining. Magnification: 400×