Fig. 7

Coculturing tumor necrosis factor (TNF)-α-treated nucleus pulposus mesenchymal stem cells (NPMSCs) with notochordal cell (NC)-rich nucleus pulposus (NP) explants increases the expression of matrix macromolecules. Representative image of immunofluorescence staining (a) and quantification analysis of collagen II protein expression in the three groups after 7 days of culture (b). Glycosaminoglycan (GAG)/DNA ratio in NPMSCs treated with different test compounds for 7 days (c). Western blot analysis (d) and densitometric quantification (e) of collagen II proteins in three groups. The mRNA expression levels of aggrecan, Sox-9, Col1α1, and Col2α1 in NPMSCs were compared within different groups after 7 days of culture (f–i). All data are expressed as mean ± SD values (n = 4). *P < 0.05