TGF-beta1 induces COX-2 expression and PGE2 synthesis through MAPK and PI3K pathways in human mesangial cells.
Transforming growth factor-beta1 (TGF-beta1) plays a fundamental role in the progression of renal diseases. Accumulating evidence has suggested that eicosanoids derived from cyclooxygenase-2 (COX-2) participate in a number of pathological processes in immune-mediated renal diseases. Mesangial cells (MC) play a major role in physiological and pathophysiological renal processes. MC express receptors for TGF-beta1, and COX-2 expression can be induced in MC. However, to date, there are no published data on the possible role of TGF-beta1 in COX-2 expression in human mesangial cells (HMC). We designed studies to determine (1) whether TGF-beta1 stimulates COX-2 expression in primary HMC, (2) whether mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) cascades are involved in TGF-beta1-induced COX-2 expression, and (3) whether prostaglandin (PG)E2 synthesis is affected by TGF-beta1 and MAP kinases and PI3K activation. Studies were performed in primary cultures of HMC and in an immortalized line of HMC. TGF-beta1 induces COX-2 promoter activity and COX-2 mRNA and protein expression in HMC. COX-2 induction is accompanied by increased PGE2 synthesis. Extracellular signal-regulated kinase (ERK)1/2, p38 MAPK, and PI3K pathway inhibition blunted TGF-beta1-induced COX-2 overexpression. We demonstrate that TGF-beta1 regulates COX-2 expression in HMC through the activation of ERK1/2, p38 MAPK, and PI3K. These results can help to elucidate the molecular mechanisms underlying the regulation of COX-2 and open up specific strategies for the treatment of glomerular disease.
Rodríguez-Barbero
A
A
Departamento de Fisiología y Farmacología, Instituto Reina Sofía de Investigación Nefrológica, Universidad de Salamanca, Campus Miguel de Unamuno, Edificio Departamental, Salamanca, Spain.
Dorado
F
F
Velasco
S
S
Pandiella
A
A
Banas
B
B
López-Novoa
J M
JM
D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism*; D015232:Dinoprostone / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006801:Humans; D050527:Mesangial Cells / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000502:physiology; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology*; D051057:Proto-Oncogene Proteins c-akt / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D016212:Transforming Growth Factor beta / Q000502:physiology*; D053773:Transforming Growth Factor beta1; D048051:p38 Mitogen-Activated Protein Kinases / Q000502:physiology
D024042:Collagen Type I; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D051546:Cyclooxygenase 2; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D015232:Dinoprostone