Figure 3.

(A–C) Fullerol rescues impairment of extracellular matrix production induced by overloaded oxidative stress. Human nucleus pulposus cells in alginate beads were treated with H₂O₂ (500 μM) alone or together with fullerol (Ful; 1 μM) for 4 hours and cultured for an additional 60 hours. (A) Cellular proteoglycan determined by a colorimetric method using the dimethylmethylene blue reagent. (B) Extracellular matrix production by immunofluorescence. Bar 50 μm. (C) The messenger ribonucleic acid expression of genes related to extracellular matrix was detected by real-time reverse transcription polymerase chain reaction (RT-PCR). Letters a and b denote P<0.05 versus control (Con) and P<0.05 versus H₂O₂ groups, respectively.

Notes: *P<0.05; **P<0.01.

Abbreviations: GAG, glycosaminoglycan; DNA, deoxyribonucleic acid; AGG, aggrecan; COL, collagen; MMP, matrix metalloproteinase; ADAMTS, a disintegrin and metalloproteinase with thrombospondin motifs; TIMP, tissue inhibitor of metalloproteinase; NS, not significant.