Interferon-tau modulates phorbol ester-induced production of prostaglandinand expression of cyclooxygenase-2 and phospholipase-A(2) from bovine endometrial cells

Antiluteolytic actions of bovine interferon-tau (bIFN-tau) require suppress ion of prostaglandin F-2 alpha (PGF(2 alpha)) production. Our objective was to test whether bIFN-tau could block PGF(2 alpha) production and synthesis of phospholipase A(2) (PLA(2)) and cyclooxygenase-2 (COX-2) enzymes induce d by a protein kinase C (PKC) stimulator (phorbol 12,13 dibutyrate; PDBu). Bovine endometrial epithelial (BEND) cells were treated with PDBu in the pr esence or absence of bIFN-tau. Medium samples were analyzed for concentrati ons of PGF(2 alpha), whole-cell extracts were analyzed for abundance of PLA , and COX-2 by immunoblotting, and RNA extracts were examined for steady-st ate levels of COX-2 mRNA by Northern blotting. The PDBu stimulated producti on of PGF(2 alpha) between 3 and 12 h, levels of COX-2 mRNA by 3 h and prot ein expression of COX-2 and PLA, by 6 and 12 h, respectively, Added concomi tantly with PDBu, bIFN-tau suppressed PGF(2 alpha) production, steady-state levels of COX-2 mRNA, and expression of COX-2 and PLA(2) proteins. Added a fter a 3-h stimulation with PDBu atone, bIFN-tau suppressed PGF(2 alpha) pr oduction after 1 h. Bovine IFN-tau inhibited intracellular mechanisms respo nsible for PCF2 alpha production in BEND cells, and this could be through b oth cytosolic and nuclear actions.