Effect of curcumin on NF- k B activation. NF-k B activation was determined in the retinal homogenate by ELISA method (kit from Active Motif.) using antibody specific for p65 subunit of NF-k B. Secondary antibody conjugated to horseradish peroxidase was used to quantify the activated form spectrophotometrically. The figure represents mean ± SD of 5–6 rats each in of the 3 groups. *P < 0.05 compared with normal or diabetes + curcumin groups.