Proton pump inhibitor induced collagen expression in colonocytes is associated with collagenous colitis

Figure 3 Expression of collagen and collagen-associated genes in CT26 cells. A: Expression of Na⁺-H⁺ exchanger gene (SLC9A2) and collagen-associated genes was examined by RT-PCR in CT26 cells treated with PPI or alkaline media. Glyceraldehyde 3-phosphate dehydrogenase (GPDH) served as an internal control; B: Expression of collagen type I, III, IV and VI in CT26 cells treated with PPI or alkaline media; C and D: The expression of collagen type I, III, IV and VI in CT26 cells was semi-quantitated. Expression in cells without treatment in 100 mg/dL glucose concentration was set to 100% as a reference. Asterisk shows significant difference from the reference. Error bar, SD calculated from 3 independent experiments by Student's t-test. PPI: Proton pump inhibitor.