Decrease in claudin-2 expression enhances cell migration in renal epithelial Madin-Darby canine kidney cells.
Migration of renal epithelial cells increases after renal tubular damage, but its mechanism has not been clarified in detail. Hyperosmotic stress increased a cellular injury concomitant with a decrease in mRNA and protein expression of claudin-2 in renal tubular epithelial Madin-Darby canine kidney cells. We hypothesized that claudin-2 is involved in the regulation of cell migration. To knockdown claudin-2 expression, we made the cells expressing doxycycline-inducible claudin-2 shRNA vector. Claudin-2 knockdown affected neither the endogenous expression levels of claudin-1, -3, -4, and -7 nor the Triton X-100 solubility of these claudins. Transepithelial electrical resistance was increased by claudin-2 knockdown without affecting permeability to FITC-dextran (4,000 Da). BrdU incorporation assay and cell counting revealed that cell proliferation and viability are unaffected by claudin-2 knockdown. In the wound-healing assay, the recovery rate of wound area was increased by claudin-2 knockdown. The mRNA expression and activity of matrix metalloproteinase-9 (MMP-9) were increased by claudin-2 knockdown. A selective MMP-9 inhibitor suppressed cell migration in the claudin-2 knockdown cells. Hyperosmotic stress increased the expression and activity of MMP-9, which were inhibited by claudin-2 overexpression. These results suggest that the decrease in claudin-2 expression enhances cell migration mediated by the increase in the expression and activity of MMP-9.
Ikari
Akira
A
Department of Pharmaco-Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan. ikari@u-shizuoka-ken.ac.jp
Takiguchi
Ayumi
A
Atomi
Kosuke
K
Sato
Tomonari
T
Sugatani
Junko
J
D000818:Animals; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D057167:Claudins / Q000235:genetics / Q000378:metabolism*; D004285:Dogs; D017097:Electric Impedance; D004847:Epithelial Cells / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology*; D005786:Gene Expression Regulation / Q000187:drug effects; D055785:Gene Knockdown Techniques; D007668:Kidney / Q000473:pathology*; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism; D061965:Matrix Metalloproteinase Inhibitors; D009997:Osmotic Pressure / Q000187:drug effects; D011480:Protease Inhibitors / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D019108:Tight Junctions / Q000187:drug effects / Q000378:metabolism
D057167:Claudins; D061965:Matrix Metalloproteinase Inhibitors; D011480:Protease Inhibitors; D012333:RNA, Messenger; D020780:Matrix Metalloproteinase 9