Fig. 5. Metalloproteinase inhibitors decrease -catenin signaling in Timp3^–/– cells. (A) Western blots of whole-cell lysates from WT and Timp3^–/– MECs revealed that metalloproteinase inhibition with recombinant TIMP3 (25 µM), GM6001 (25 µM) and PD166793 (50 µM) for 24 hours returned dephosphorylated -catenin to levels comparable to the WT. (B) The reduction in Ccnd1 gene expression in Timp3^–/– MECs was reversed by 24-hour treatment with recombinant TIMP3 (10 µM) (^*P<0.001), GM6001 (10 µM) (^**P<0.01) and PD166793 (25 µM) (^***P<0.05) when compared with the untreated control. (C) The increase in Mmp7 gene expression in Timp3^–/– MECs was significantly mitigated by treatment with recombinant TIMP3 (10 µM) (^*P<0.001), GM6001 (10 µM) (^*P<0.001) and PD166793 (25 µM) (^**P<0.05) for 24 hours. ANOVA was performed to assess the statistical significance between WT and Timp3^–/– cells. Values are expressed as mean ± s.e.m. of three independent experiments.