Inflammatory bowel disease (IBD) is often triggered and/or exacerbated by nonsteroidal anti-inflammatory drugs (NSAIDs). Among various prostanoids affected by NSAIDs, prostaglandin E2 (PGE2), in particular, seems to play critical roles in IBD via the EP4 receptor, one of the four PGE2 receptor subtypes (EP1-4). An EP4 agonist, [[3-[[(1R,2S,3R)-3-hydroxy-2-[(1E,3S)-3-hydroxy-4-[3-(methoxymethyl)...

OBJECTIVES To confirm the downregulation of PTGER4 mRNA in the conjunctiva of Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) and ocular cicatricial pemphigoid (OCP) patients and to examine the expression of its EP4 protein in the conjunctival epithelium of patients with various ocular surface disorders. DESIGN Case-control study. SETTING AND PARTICIPANTS We performed quantita...

We examined, by using a specific PGE receptor subtype EP4 agonist and antagonist, the involvement of EP4 receptors in duodenal HCO(3)(-) secretion induced by PGE(2) and mucosal acidification in rats. Mucosal acidification was achieved by exposing a duodenal loop to 10 mM HCl for 10 min, and various EP agonists were given intravenously 10 min before the acidification. Secretion of HCO(3)(-) was ...

Four prostaglandin E (EP) receptor subtypes have been identified and cloned, designated as EP1, EP2, EP3 and EP4. These EP receptors are members of the G-protein coupled receptor family. EP3 receptor signals are primarily involved in inhibition of adenylyl cyclase via Gi activation, while EP2 and EP4 receptor signals cause a stimulation of adenylyl cyclase via Gs activation. Immune cells, such ...

Previous evidence has implicated E prostanoid receptor 4 (EP4) in mechanical hyperalgesia induced by subplantar inflammation. However, its role in chronic arthritis remains to be further defined because previous attempts have generated two conflicting lines of evidence, with one showing a marked reduction of arthritis induced by a collagen antibody in mice lacking EP4, but not EP1-EP3, and the ...

EP4 expression in human glioblastoma cells correlates with growth on soft agar. The cyclooxygenase inhibitor sulindac sulfide first altered specificity protein-1 (Sp-1) and early growth response gene-1 expression, then increased the expression of nonsteroidal antiinflammatory drug-activated gene 1 and activating transcription factor 3, and then decreased EP4 expression. EP4 suppression was depe...

Prevention and treatment of pathological inflammatory processes requires application of various classes of immune suppressors, such as calcineurin inhibitors, steroids and non-steroid inhibitors of prostaglandin synthesis. However, each type of these immune suppressors causes less or more serious adverse side-effects. Exploration of the role played by prostanoids in the immune response and iden...

UNLABELLED MicroRNAs (miRs) are small regulatory molecules emerging as potential biomarkers in cancer. Previously, it was shown that COX-2 expression promotes breast cancer progression via multiple mechanisms, including induction of stem-like cells (SLC), owing to activation of the prostaglandin E2 receptor EP4 (PTGER4). COX-2 overexpression also upregulated microRNA-526b (miR-526b), in associa...

Elevated levels of PGE(2) have been reported in synovial fluid and cartilage from patients with osteoarthritis (OA). However, the functions of PGE(2) in cartilage metabolism have not previously been studied in detail. To do so, we cultured cartilage explants, obtained from patients undergoing knee replacement surgery for advanced OA, with PGE(2) (0.1-10 muM). PGE(2) inhibited proteoglycan synth...

Background Platelets play a central role in haemostasis. Blood vessel injury leads to platelet aggregation and also invokes an inflammatory response leading to the formation of prostanoids like prostaglandin E2 (PGE2) and prostacyclin (PGI2). It is known that low concentrations of PGE2 enhance and high concentrations inhibit platelet aggregation. PGE2 mediates its effect through four receptors:...