Figure 10. Effects of glucosamine (GlcN) on the expression of endoplasmic reticulum (ER) stress markers, Hsp27, Hsp70, Hsp90, Grp78, and CHOP-GADD. Human retinal pigment epithelial cell line (ARPE-19) cells were treated with 5 mM GlcN, 30 mM glucose or 1 μm thapsigargin (TG), a pharmacological ER stress inducers as a positive control, for 24 or 48 h. The expression of ER stress markers in ARPE-19 cells was analyzed by western blot.