Abstract:Objective To investigate whether Baicalein (BAI) protects nucleus pulposus cells (NPCs) exposed to tert-Butyl hydroperoxide (TBHP). Methods NPCs were extracted from 8-week-old mice and cultured to passages 2 and 3 for experiments in control, model, and baicalein groups. SA-β-galactosidase staining was used to detect senescence of NPCs. Real-time quantitative PCR was used to measure aggrecan, collagen Ⅱ, matrix metalloproteinase-3 (MMP-3), matrix metalloproteinase-9 (MMP-9), tumor necrosis factor α (TNF-α), interleukin (IL)-1β, p53 and p16 mRNA expression. TNF-α was detected by immunofluorescence. Protein expression of aggrecan, p53, p16, IL-1β and TNF-α was detected by Western blot. Results The concentration of TBHP was 100 μmol/ L, and the treatment time was 4 h. The optimal concentration of baicalein was 1 μg/ mL with a treatment time of 24 h. Compared with the control group, the positive rate of SA-β-galactose staining in the TBHP group was significantly increased (P<0. 05), p53, p16, IL-1β and TNF-α mRNA and protein expression was significantly increased ( P<0. 05), and MMP-3 mRNA expression was significantly increased (P<0. 05). MMP-9 mRNA expression was increased, but the difference was not statistically significant (P>0. 05), aggrecan mRNA and protein expression was significantly decreased (P<0. 05), collagen Ⅱ mRNA expression was decreased, but the difference was not statistically significant (P>0. 05), and IL-6 protein expression was increased, but the difference was not statistically significant (P>0. 05). Compared with the model group, the positive rate of SA-β-galactose staining in the baicalein group was significantly lower (P<0. 05). p53, p16, IL-1β, and TNF-α mRNA and protein expression was significantly lower (P<0. 05), and MMP-3 and MMP-9 mRNA expression was significantly lower (P<0. 05). Aggrecan mRNA and protein expression was significantly increased (P<0. 05), collagen Ⅱ mRNA expression was significantly increased (P<0. 05), and IL-6 protein expression was significantly decreased (P<0. 05). Conclusions Baicalein delays senescence of NPCs induced by TBHP.