MMP9 and diabetic retinopathy: It has been shown that interleukin-12 has anti-angiogenic properties by lowering the concentrations of MMP9 and VEGFA throughout the bloodstream [228]. Zheng and colleagues mixed IL-12 with PLGA nanomaterials and showed that this combination was more effective in inhibiting the expression of MMP9 and VEGFA in the diabetic retinopathy mouse model and endothelial cells of rats.