Premium
Cyclooxygenase 2 and prostaglandin E 2 regulate the attachment of calcium oxalate crystals to renal epithelial cells
Author(s) -
Miyazawa Katsuhito,
Takahashi Yoshitaka,
Morita Nobuyo,
Moriyama Manabu T,
Kosaka Takeo,
Nishio Matomo,
Yoshimoto Tanihiro,
Suzuki Koji
Publication year - 2012
Publication title -
international journal of urology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 67
eISSN - 1442-2042
pISSN - 0919-8172
DOI - 10.1111/j.1442-2042.2012.03060.x
Subject(s) - cyclooxygenase , calcium oxalate , kidney , transfection , prostaglandin , nephrocalcinosis , calcium , prostaglandin e2 , medicine , microbiology and biotechnology , endocrinology , cell culture , enzyme , biochemistry , chemistry , biology , genetics
Objective: To determine the roles of endogenous cyclooxygenase 2 and prostaglandin E 2 in crystal‐cell binding, which is considered to be an important step in the development of intratubular nephrocalcinosis. Methods: An expression plasmid for human cyclooxygenase 2 was introduced into Madin–Darby canine kidney cells using the lipofection method. Cyclooxygenase activity was measured using thin‐layer chromatography, and the prostaglandin E 2 concentration was determined with an enzyme immunoassay. In addition, crystal attachment was evaluated with a liquid scintillation counter using [ 14 C] calcium oxalate monohydrate crystals, and immunohistochemistry and an enzyme immunoassay were used to analyze and quantify the expression of hyaluronan, a crystal‐binding molecule. Results: Cyclooxygenase 2‐overexpressing Madin–Darby canine kidney cells produced about 10‐fold more prostaglandin E 2 than wild‐type Madin–Darby canine kidney cells, and their hyaluronan production was also upregulated. The attachment of calcium oxalate monohydrate crystals to cyclooxygenase 2‐overexpressing Madin–Darby canine kidney cells was significantly reduced compared with their attachment to wild‐type and mock‐transfected Madin–Darby canine kidney cells. Pre‐incubation of the cyclooxygenase 2‐overexpressing cells, as well as the mock‐transfected and wild‐type cells with the cyclooxygenase 2 selective inhibitor etodolac, increased the cellular attachment of calcium oxalate monohydrate crystals in a dose‐dependent manner. Conclusions: These findings suggest that cyclooxygenase 2 expression and the resultant increase in endogenous prostaglandin E 2 , leading to increased hyaluronan production, help to prevent nephrocalcinosis by inhibiting the attachment of calcium oxalate monohydrate crystals to the surface of renal epithelial cells.