Research Paper Volume 10, Issue 1 pp 131—143

Rapamycin prevents the intervertebral disc degeneration via inhibiting differentiation and senescence of annulus fibrosus cells

Figure 5. Gene expression in rabbit AFSCs cultured in growth medium with five different conditions for 6 days and tested by qRT-PCR. (A) Collagen I gene expression; (B) MMP-3 gene expression; (C) MMP-13 gene expression; (D) IL-1β gene expression; (E) IL-6 gene expression; (F) TNF-α gene expression. The results indicated that low concentration of bleomycin did not change the expression of collagen I in AF cells, however, high concentration of bleomycin (50 μg/ml) decreased collagen type I expression in AF cells. Adding low concentration of rapamycin (25 nM) in bleomycin treated AF cells didn’t change the collagen I expression, but high concentration of rapamycin (50 nM) increased by 50% the collagen I levels in AF cells (A). In addition, the gene expression of MMP-3 (B) and MMP-13 (C) was increased in a bleomycin concentration-dependent manner. Rapamycin decreased the expression of MMP-3 and MMP-13 in AF cells compared to bleomycin alone. Moreover, inflammatory-related genes, such as IL-1β (D), IL-6 (E) and TNF-α (F) were increased in bleomycin treated AF cells; rapamycin inhibited the expression of these inflammation genes. *p<0.05 compared to control, #P<0.05 compared to bleomycin 50 μg/ml.