TY - JOUR
T1 - Contribution of cyclooxygenase-1 and cyclooxygenase-2 to prostanoid formation by human enterocytes stimulated by calcium ionophore and inflammatory agents
AU - Longo, Walter E.
AU - Panesar, Ninder
AU - Mazuski, John
AU - Kaminski, Donald L.
PY - 1998
Y1 - 1998
N2 - The stimulation of intestinal epithelial cell cyclooxygenase (COX) enzymes with inflammatory agents and the inhibition of COX-1 and COX-2 enzymes has the potential to increase understanding of the role of these enzymes in intestinal inflammation. The aim of this study was to determine the contributions of COX-1 and -2 to the production of specific prostanoids by unstimulated and stimulated intestinal epithelial cells. Cultured enterocytes were stimulated with lipopolysaccharide (LPS), interleukin-1 (IL- 1)β (IL-1β), and calcium ionophore (Ca Ion), with and without COX inhibitors. Valerylsalicylic acid (VSA) was employed as the COX-1 inhibitor, and SC-58125 and NS398 were used as the COX-2 inhibitors. Prostanoids were quantitated by Elisa assay. Western immunoblotting demonstrated the presence of constitutive COX-1 and inducible COX-2 enzyme. Unstimulated prostanoid formation was not decreased by the COX-1 inhibitor. All of the stimulants evaluated increased prostaglandin E2 (PGE2) production. Only Ca Ion stimulated prostaglandin D2 (PGD2) production while IL-1β, and Ca Ion, but not LPS, increased prostaglandin F(2α) (PGF(2α)) formation. Ca Ion- stimulated prostanoid formation was uniformly inhibited by COX-2, but not COX-1, inhibitors. IL-1β-stimulated PGE2 and PGF(2α) formation was significantly decreased by both COX-1 and COX-2 inhibitors. VSA, in a dose- dependent manner, significantly decreased IL-1β-stimulated PGE2 and PGF(2α) production. Unstimulated prostanoid formation was not dependent on constitutive COX-1 activity. The stimulation of intestinal epithelial cells by Ca Ion seemed to uniformly produce prostanoids through COX-2 activity. There was no uniform COX-1 or COX-2 pathway for PGE and PGF(2α) formation stimulated by the inflammatory agents, suggesting that employing either a COX-1 or COX-2 inhibitor therapeutically will have varying effects on intestinal epithelial cells dependent on the prostanoid species and the inflammatory stimulus involved.
AB - The stimulation of intestinal epithelial cell cyclooxygenase (COX) enzymes with inflammatory agents and the inhibition of COX-1 and COX-2 enzymes has the potential to increase understanding of the role of these enzymes in intestinal inflammation. The aim of this study was to determine the contributions of COX-1 and -2 to the production of specific prostanoids by unstimulated and stimulated intestinal epithelial cells. Cultured enterocytes were stimulated with lipopolysaccharide (LPS), interleukin-1 (IL- 1)β (IL-1β), and calcium ionophore (Ca Ion), with and without COX inhibitors. Valerylsalicylic acid (VSA) was employed as the COX-1 inhibitor, and SC-58125 and NS398 were used as the COX-2 inhibitors. Prostanoids were quantitated by Elisa assay. Western immunoblotting demonstrated the presence of constitutive COX-1 and inducible COX-2 enzyme. Unstimulated prostanoid formation was not decreased by the COX-1 inhibitor. All of the stimulants evaluated increased prostaglandin E2 (PGE2) production. Only Ca Ion stimulated prostaglandin D2 (PGD2) production while IL-1β, and Ca Ion, but not LPS, increased prostaglandin F(2α) (PGF(2α)) formation. Ca Ion- stimulated prostanoid formation was uniformly inhibited by COX-2, but not COX-1, inhibitors. IL-1β-stimulated PGE2 and PGF(2α) formation was significantly decreased by both COX-1 and COX-2 inhibitors. VSA, in a dose- dependent manner, significantly decreased IL-1β-stimulated PGE2 and PGF(2α) production. Unstimulated prostanoid formation was not dependent on constitutive COX-1 activity. The stimulation of intestinal epithelial cells by Ca Ion seemed to uniformly produce prostanoids through COX-2 activity. There was no uniform COX-1 or COX-2 pathway for PGE and PGF(2α) formation stimulated by the inflammatory agents, suggesting that employing either a COX-1 or COX-2 inhibitor therapeutically will have varying effects on intestinal epithelial cells dependent on the prostanoid species and the inflammatory stimulus involved.
KW - Calcium ionophore
KW - Cyclooxygenase-1
KW - Cyclooxygenase-2
KW - Enterocytes
KW - Human
KW - Inflammatory agents
KW - Prostanoid formation
UR - http://www.scopus.com/inward/record.url?scp=0032461407&partnerID=8YFLogxK
U2 - 10.1016/S0090-6980(98)00058-6
DO - 10.1016/S0090-6980(98)00058-6
M3 - Article
C2 - 9990676
AN - SCOPUS:0032461407
SN - 0090-6980
VL - 56
SP - 325
EP - 339
JO - Prostaglandins and Other Lipid Mediators
JF - Prostaglandins and Other Lipid Mediators
IS - 5-6
ER -