Figure 4. Unfolded protein response-specific proteins were not upregulated in the lens epithelial cells of galactosemic rats that were administered cellular osmolytes

Lenses from 15 galactose-fed rats and controls at 15 days were carefully removed by dissection and homogenized in RIPA buffer. The capsule and insoluble proteins were separated by centrifugation. Protein blot analysis with antibodies to Bip/GRP78, CHOP, ATF4, and GAPDH are shown (A). A luminol reagent was used to visualize the specific protein bands. In each experiment, GAPDH was used as an internal marker. The intensity of each UPR specific band was normalized to the intensity of GAPDH; the ratio of protein bands in treated and control rats is shown in the bar graph (B), which obtained an average of at least three separate experiments. Activation of ER stress was suppressed by each of the osmolytes, and as a result, more LECs remained viable.