Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Prostaglandin D2 (PGD2) is a mast cell-derived mediator that seems to play a role in asthma and allergic diseases. It is the only primary prostanoid to activate human eosinophils, which it accomplishes through the DP2 receptor/chemoattractant receptor-homologous molecule expressed on T helper cell type 2 (Th2) cells (CRTH2). In addition, PGD2 has both pro- and anti-inflammatory effects via the adenylyl cyclase-coupled DP1 receptor. To attempt to identify potent and selective DP2 receptor agonists we compared the abilities of a series of PGD2 analogs to activate eosinophils via the DP2 receptor with their abilities to stimulate adenylyl cyclase in platelets via the DP1 receptor. All of the PGD2 analogs tested stimulated CD11b expression and actin polymerization with a rank order of potency of 15R-methyl-PGD2 > PGD2 > 17-phenyl-18,19,20-trinor-PGD2 > 15S-methyl-PGD2 approximately equal16,16-dimethyl-PGD2 > 11-keto-fluprostenol. Surprisingly, 15R-methyl-PGD2, which has the unnatural R-configuration at carbon 15, was about 5 times more potent than PGD2 and about 75 times more potent than 15S-methyl-PGD2. 15R-methyl-PGD2 (EC50 value of 1.7 nM) was also much more potent as an eosinophil chemoattractant than PGD2 (EC50 value of 10 nM) and 15S-methyl-PGD2 (EC50 value of 128 nM). Cross-desensitization experiments indicated that 15R-methyl-PGD2 acts through the DP2 receptor. None of the PGD2 analogs tested elevated platelet cAMP by more than 20% of the maximal level in response to PGD2. However, in contrast to eosinophils, the most active was 15S-methyl-PGD2. In conclusion, 15R-methyl-PGD2 is the most potent known DP2 receptor agonist, and because of its selectivity and resistance to metabolism, should be a useful tool in probing the physiological role of this receptor in inflammatory diseases.
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PMID:15R-methyl-prostaglandin D2 is a potent and selective CRTH2/DP2 receptor agonist in human eosinophils. 1249 Jun 11

Allergic pathologies are often associated with IgE production, mast cell activation, and eosinophilia. PGD2 is the major eicosanoid, among several inflammatory mediators, released by mast cells. PGD2 binds to two membrane receptors, D prostanoid receptor (DP)1 and DP2, endowed with antagonistic properties. In humans, DP2 is preferentially expressed on type 2 lymphocytes, eosinophils, and basophils and mediates chemotaxis in vitro. Although not yet supported by in vivo studies, DP2 is thought to be important in the promotion of Th2-related inflammation. Herein, we demonstrate that mouse eosinophils express both DP1 and DP2 and that PGD2 exerts in vitro chemotactic effects on eosinophils through DP2 activation. Furthermore, 13,14-dihydro-15-keto-PGD2, a specific DP2 agonist not only increases eosinophil recruitment at inflammatory sites but also the pathology in two in vivo models of allergic inflammation: atopic dermatitis and allergic asthma. By contrast, DP1 activation tends to ameliorate the pathology in asthma. Taken together, these results support the hypothesis that DP2 might play a critical role in allergic diseases and underline the interest of DP2 antagonists in human therapy.
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PMID:Activation of the prostaglandin D2 receptor DP2/CRTH2 increases allergic inflammation in mouse. 1574 9

Thyroid eye disease (TED) is a debilitating disorder characterized by the accumulation of adipocytes and hyaluronan (HA). Production of HA by fibroblasts leads to remarkable increases in tissue volume and to the anterior displacement of the eyes. Prostaglandin D(2) (PGD(2)), mainly produced by mast cells, promotes orbital fibroblast adipogenesis. The mechanism by which PGD(2) influences orbital fibroblasts and their synthesis of HA is poorly understood. We report here that mast cell-derived PGD(2) is a key factor that promotes HA biosynthesis by orbital fibroblasts. Primary orbital fibroblasts from TED patients were isolated and used to test the effects of PGD(2), prostaglandin J(2), as well as prostaglandin D receptor (DP) agonists and antagonists on HA synthesis. The expression of HA synthase (HAS), hyaluronidase, DP1, and DP2 mRNA levels was assessed by PCR. Small interfering RNAs against HAS1 or HAS2 were used to assess the importance of HAS isoforms on HA production. Treatment of human orbital fibroblasts with PGD(2) and PGJ(2) increased HA synthesis and HAS mRNA. HAS2 was the dominant isoform responsible for HA production by PGD(2). The effect of PGD(2) on HA production was mimicked by the selective DP1 agonist BW245C. The DP1 antagonist MK-0524 completely blocked PGD(2)-induced HA synthesis. Human mast cells (HMC-1) produced PGD(2). Co-culture of HMC-1 cells with orbital fibroblasts induced HA production and inhibition of mast cell-derived PGD(2) prevented HA synthesis. Mast cell-derived PGD(2) increased HA production via activation of DP1. Selectively targeting the production of PGD(2) and/or activation of DP1 may prevent pathological changes associated with TED.
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PMID:Mast cell-derived prostaglandin D2 controls hyaluronan synthesis in human orbital fibroblasts via DP1 activation: implications for thyroid eye disease. 2030 56

Sensitization of esophageal afferents plays an important role in esophageal nociception, but the mechanism is less clear. Our previous studies demonstrated that mast cell (MC) activation releases the preformed mediators histamine and tryptase, which play important roles in sensitization of esophageal vagal nociceptive C fibers. PGD2 is a lipid mediator released by activated MCs. Whether PGD2 plays a role in this sensitization process has yet to be determined. Expression of the PGD2 DP1 and DP2 receptors in nodose ganglion neurons was determined by immunofluorescence staining, Western blotting, and RT-PCR. Extracellular recordings were performed in ex vivo esophageal-vagal preparations. Action potentials evoked by esophageal distension were compared before and after perfusion of PGD2, DP1 and DP2 receptor agonists, and MC activation, with or without pretreatment with antagonists. The effect of PGD2 on 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI)-labeled esophageal nodose neurons was determined by patch-clamp recording. Our results demonstrate that DP1 and DP2 receptor mRNA and protein were expressed mainly in small- and medium-diameter neurons in nodose ganglia. PGD2 significantly increased esophageal distension-evoked action potential discharges in esophageal nodose C fibers. The DP1 receptor agonist BW 245C mimicked this effect. PGD2 directly sensitized DiI-labeled esophageal nodose neurons by decreasing the action potential threshold. Pretreatment with the DP1 receptor antagonist BW A868C significantly inhibited PGD2 perfusion- or MC activation-induced increases in esophageal distension-evoked action potential discharges in esophageal nodose C fibers. In conclusion, PGD2 plays an important role in MC activation-induced sensitization of esophageal nodose C fibers. This adds a novel mechanism of visceral afferent sensitization.
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PMID:Role of prostaglandin D2 in mast cell activation-induced sensitization of esophageal vagal afferents. 2347 41