CASP3 and diabetic retinopathy: Moreover, we have shown that LB extract and taurine dose dependently downregulate caspase-3 protein expression and the enzymatic activity of caspase-3.We conclude that taurine, a major component of LB, and the LB extract, have a cytoprotective effect against glucose exposure in a human retinal epithelial cell line and may provide useful approaches to delaying diabetic retinopathy progression.