Figure 9. Smad3 gene deficiency impacted stromal ECM protein modulation via MMP and TIMP expression during active wound healing in mice after alkali injury. A: The comparative mRNA expressions of MMP1, MMP2, and MMP9 showed significantly reduced expression in Smad3^−/− mouse corneal tissue after alkali injury compared with Smad3^+/+ mouse corneal tissue after alkali injury. B: The western blot showed similar trends of MMP and TIMP expression in the corneal tissue lysate of Smad3^−/− mice compared with Smad3^+/+ mouse corneal tissue lysate. C: Gelatin zymography showed the pro and active MMP patterns in the corneal tissue lysate of Smad3^−/− mice compared with Smad3^+/+ mouse corneal tissue lysate. The results are expressed as mean ± SEM, and p<0.05 was considered significant.