Fig. 4

Histological staining with safranin-O (×100) of conditioned porcine cartilage disks. After 14 days of treatment with various concentrations of corticosteroids in combination with HA, the proteoglycans content in the cartilage tissue stains is indicated by safranin-O staining. The extent of the morphological change and the proteoglycans content were compared between all of the treatment groups. (a) Safranin-O staining representative of the results are shown start from upper row and left to right: control, HA, Pred50, Pred25, Pred12.5, P50 + HA, P25 + HA, P12.5 + HA, Dex50, Dex25, Dex12.5 and the last row D50 + HA, D25 + HA, D12.5 + HA, respectively. The Dex and the HA-treated groups performed rather efficiently, as indicated by the intense red hue, better than the other groups, including the control. The scale bars represent 100 μm. (b) An increase in the safranin-O intensity (relative to the control) in the steroid treatment groups is shown in the bar chart which is exhibited as the mean ± SD of the triplicate independent. Significant differences are considered to exist when p < 0.05: “a” stands for significant differences compared with the control group; “b” denotes significant differences compared with the HA group; dagger (‡) stands for significant differences compared with all the Pred-treated groups; hash (#) denotes significant differences compared with all the Dex-treated groups; and asterisk (*) stands for significant differences between the treatment groups