Figure 6.

Effect of microsphere degradation products on nucleus pulposus (NP) properties. (a) Construct glycosaminoglycan (GAG) content. (b) GAG released into treatment media. (c) mRNA expression levels for inducible nitric oxide synthase (INOS), a disintegrin and metalloproteinase with thrombospondin motifs 4 (ADAMTS-4), and matrix metalloproteinase 13 (MMP-13) were normalized to glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and expressed as a ratio to untreated constructs. Values are mean ± standard deviation. *P < 0.05 versus untreated constructs; ◆P < 0.05 versus IL-1β-only treated constructs.