Inhibition of microsomal PGE synthase‐1 reduces human vascular tone by increasing PGI2: a safer alternative to COX‐2 inhibition

• DOI: 10.1111/bph.13939
• Publication Date: 2017-07-04T13:17:57Z
• Authors: Gulsev Ozen; Ingrid Gomez; Armond Daci; Catherine Deschildre; Lilia Boubaya; Onder Teskin; B Sonmez Uydeş‐Doğan; Per‐Johan Jakobsson; Dan Longrois; Gokce Topal; Xavier Norel
• Keywords: Inflammation; Male; 0303 health sciences; Thiophenes; Middle Aged; Epoprostenol; 3. Good health; Norepinephrine; 03 medical and health sciences; Cyclooxygenase 2; Humans; Vasoconstrictor Agents; Cyclooxygenase Inhibitors; Female; Saphenous Vein; Mammary Arteries; Aged; Prostaglandin-E Synthases

Background and PurposeThe side effects of cyclooxygenase‐2 (COX‐2) inhibitors on the cardiovascular system could be associated with reduced prostaglandin (PG)I2 synthesis. Microsomal PGE synthase‐1 (mPGES‐1) catalyses the formation of PGE2 from COX‐derived PGH2. This enzyme is induced under inflammatory conditions and constitutes an attractive target for novel anti‐inflammatory drugs. However, it is not known whether mPGES‐1 inhibitors could be devoid of cardiovascular side effects. The aim of this study was to compare, in vitro, the effects of mPGES‐1 and COX‐2 inhibitors on vascular tone in human blood vessels.Experimental ApproachThe vascular tone and prostanoid release from internal mammary artery (IMA) and saphenous vein (SV) incubated for 30 min with inhibitors of mPGES‐1 or COX‐2 were investigated under normal and inflammatory conditions.Key ResultsIn inflammatory conditions, mPGES‐1 and COX‐2 proteins were more expressed, and increased levels of PGE2 and PGI2 were released. COX‐2 and NOS inhibitors increased noradrenaline induced vascular contractions in IMA under inflammatory conditions while no effect was observed in SV. Interestingly, the mPGES‐1 inhibitor significantly reduced (30–40%) noradrenaline‐induced contractions in both vessels. This effect was reversed by an IP (PGI2 receptor) antagonist but not modified by NOS inhibition. Moreover, PGI2 release was increased with the mPGES‐1 inhibitor and decreased with the COX‐2 inhibitor, while both inhibitors reduced PGE2 release.Conclusions and ImplicationsIn contrast to COX‐2 inhibition, inhibition of mPGES‐1 reduced vasoconstriction by increasing PGI2 synthesis. Targeting mPGES‐1 could provide a lower risk of cardiovascular side effects, compared with those of the COX‐2 inhibitors.Linked ArticlesThis article is part of a themed section on Targeting Inflammation to Reduce Cardiovascular Disease Risk. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.22/issuetoc and http://onlinelibrary.wiley.com/doi/10.1111/bcp.v82.4/issuetoc