Epoxyeicosatrienoic acids and their sulfonimide derivatives stimulate tyrosine phosphorylation and induce mitogenesis in renal epithelial cells

Jian Kang Chen, John R. Falck, Komandla Malla Reddy, Jorge Capdevila, Raymond C. Harris

Research output: Contribution to journalArticlepeer-review

124 Scopus citations


In our present studies utilizing a well characterized proximal tubule cell line, LLCPKc14, we determined that all four EET regioisomers (5,6-EET, 8,9-EET, 11,12-EET, and 14,15-EET) stimulated [3H]thymidine incorporation, with 14,15-EET being the most potent. In contrast, no mitogenic effects were seen with arachidonic acid, other cP450 arachidonate metabolites (12R- hydroxyeicosatetraenoic acid (12R-HETE), 14,15-dihydroxyeicosatrienoic acid (14,15-DHET), or 20-HETE), or lipoxygenase metabolites (5S-HETE, leukotriene B4, or lipoxin A4). We found that their metabolically more stable sulfonimide (SI) analogs (11,12-EET-SI and 14,15-EET-SI) were also potent mitogens. In addition 14,15-EET-SI also increased cell proliferation as well as expression of both c-fos and egr-1 mRNA. The protein kinase C and A inhibitors, H-7 and H-8, or the cyclooxygenase inhibitor, indomethacin, had no effect upon 14,15-EET-induced [3H]thymidine incorporation, but the selective tyrosine kinase inhibitor, genistein, significantly inhibited it. Immunoprecipitation and immunoblotting demonstrated increased tyrosine phosphorylation of PI3-kinase and epidermal growth factor receptor (EGFR) within 1 min of EET administration. EETs also stimulated association of PI3- kinase with EGFR. PI3-kinase inhibitors, wortmannin and LY 294002, markedly inhibited 14,15-EET-SI-stimulated [3H]thymidine incorporation. In addition, 14,15-EET-SI administration stimulated tyrosine phosphorylation of src homologous and collagen-like protein (SHC) and association of SHC with both growth factor receptor-binding protein (GRB2) and EGFR. Mitogen-activated protein kinase was also activated within 5 min. Pretreatment of the cells with the mitogen-activated protein kinase kinase inhibitor, PD98059, inhibited the 14,15-EET-SI-stimulated [3H]thymidine incorporation. Moreover, immunoblotting indicated that 14,15-EET stimulated tyrosine phosphorylation of the specific pp60(c-src) substrate p120 and c-Src association with EGFR. 14,15-EET increased src kinase activity within 1 min. Our data indicate that EETs are potent mitogens for renal epithelial cells, and the mitogenic effects of the EETs are mediated, at least in part, by the activation of Src kinase and initiation of a tyrosine kinase phosphorylation cascade.

Original languageEnglish (US)
Pages (from-to)29254-29261
Number of pages8
JournalJournal of Biological Chemistry
Issue number44
StatePublished - Oct 30 1998
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology


Dive into the research topics of 'Epoxyeicosatrienoic acids and their sulfonimide derivatives stimulate tyrosine phosphorylation and induce mitogenesis in renal epithelial cells'. Together they form a unique fingerprint.

Cite this