PGE2-mediated cytoprotection in renal epithelial cells: Evidence for a pharmacologically distinct receptor

Research output: Contribution to journalArticle

34 Scopus citations

Abstract

Although the exact mechanism of prostaglandin E2 (PGE2)-mediated cytoprotection has not been elucidated, its ability to induce cytoprotection in cell culture suggests this action occurs at the cellular level. The present studies were conducted to determine whether PGE2 induces protection against 2,3,5-(trisglutathion-S-yl)-hydroquinone [2,3,5-(trisglutathion-S- yl)-HQ]-mediated cytotoxicity in a renal proximal tubule epithelial cell line (LLC-PK1) and to delineate the cellular and molecular mechanisms associated with this response. Pretreatment of LLC-PK1 cells with 0.01-40 μM PGE2 for 24 h fully protects against a moderately toxic concentration of 2,3,5-(trisglutathion-S-yl)-HQ. PGE2-mediated cytoprotection is observed in cells pretreated at pH 7.4 but not at pH 7.8. However, cytoprotection is observed in LLC-PK1 cells pretreated with the PGE2 analog, 11-deoxy- 16,16-dimethyl PGE2 (DDM-PGE2) but not with the PGE2 receptor [E- prostanoid (EP)] agonists 17-phenyltrinor PGE2 (EP1), 11-deoxy PGE1 (EP2/EP4), sulprostone (EP1/EP3), PGE1, or PGA2. 12-O- tetradecanoylphorbol-13-acetate (TPA), a potent activator of protein kinase C (PKC), also induces cytoprotection, supporting a role for this pathway in the cytoprotective response. PGE2, DDM-PGE2, and TPA all induce the binding of nuclear proteins to a TPA responsive element (TRE) whereas analogs that did not induce cytoprotection (PGE1, 17-phenyltrinor PGE2, sulprostone) were without effect. DDM-PGE2- and TPA-mediated cytoprotection and TRE binding activity are inhibited by N-(2{[3-(4-bromophenyl)-2- propenyl]-amino}-ethyl)-5-isoquinolinesulfonamide (H-89) a PKC inhibiter. These data suggest that cytoprotection by PGE2 and DDM-PGE2 in LLC-PK1 cells is mediated by a PKC-coupled receptor, which is pharmacologically distinct from the presently classified EP receptor subtypes.

Original languageEnglish (US)
Pages (from-to)F507-F515
JournalAmerican Journal of Physiology - Renal Physiology
Volume273
Issue number4 42-4
StatePublished - Oct 1 1997

Keywords

  • E-prostanoid receptor
  • Kidney
  • Protein kinase C
  • Quinone-thioether

ASJC Scopus subject areas

  • Physiology
  • Urology

Fingerprint Dive into the research topics of 'PGE<sub>2</sub>-mediated cytoprotection in renal epithelial cells: Evidence for a pharmacologically distinct receptor'. Together they form a unique fingerprint.

  • Cite this