Figure 7. Effect of naringenin on caseinolytic activity of MMP-3 secretion in rat chondrocytes. Primary cultured articular chondrocytes were pretreated with 20 and 40 μM of naringenin. MMP-3 activity was estimated with casein zymography (A) Coomassie blue-stained polyacrylamide gel of casein zymography; (B) relative intensity of bands. Data are reported as means±SEM *P≤0.05, compared to negative control (PBS); ^#P≤0.05 and ^{# #}P≤0.01, compared IL-1β treated culture (ANOVA with Bonferonni’s post hoc multiple corrections).