Metabolites 13,14-Dihydro-15-keto-PGE2 Participates in Bifidobacterium animalis F1-7 to Alleviate Opioid-Induced Constipation by 5-HT Pathway

SCOPE

People suffer from constipation caused by many factors, including constipation (Opioid-Induced Constipation, OIC) during analgesic treatment. Microorganisms may be a potent solution to this problem, but the mechanism is still unclear.

METHODS AND RESULTS

Based on models in vivo and in vitro, the potential mechanism involving Bifidobacterium animalis F1-7 (B. animalis F1-7), screened in the previous studies, is explored through non-targeted metabonomics, electrophysiological experiment and molecular level docking. The results showed that B. animalis F1-7 effectively alleviates OIC and promotes the expression of chromogranin A (CGA) and 5-hydroxytryptamine (5-HT). The metabolite 13,14-dihydro-15-keto-PGE2 related to B. animalis F1-7 is found, which has a potential improvement effect on OIC at 20 mg kg BW-1 in vivo. At 30 ng mL-1 it effectively stimulates secretion of CGA/5-HT (408.95 ± 1.18 ng mL-1 ) by PC-12 cells and changes the membrane potential potassium ion current without affecting the sodium ion current in vitro. It upregulates the target of free fatty acid receptor-4 protein(FFAR4/β-actin, 0.81 ± 0.02).

CONCLUSION

The results demonstrate that metabolite 13,14-dihydro-15-keto-PGE2 participated in B. animalis F1-7 to alleviate OIC via the 5-HT pathway.

Deletion of the gene encoding prostamide/prostaglandin F synthase reveals an important role in regulating intraocular pressure

Prostamide/prostaglandin F synthase (PM/PGFS) is an enzyme with very narrow substrate specificity and is dedicated to the biosynthesis of prostamide F_2α and prostaglandin F_2α (PGF_2α.). The importance of this enzyme, relative to the aldo-keto reductase (AKR) series, in providing functional tissue prostamide F_2α levels was determined by creating a line of PM/PGFS gene deleted mice. Deletion of the gene encoding PM/PGFS (Fam213b / Prxl2b) was accomplished by a two exon disruption. Prostamide F_2α levels in wild type (WT) and PM/PGFS knock-out (KO) mice were determined by LC/MS/MS. Deletion of Fam213b (Prxl2b) had no observed effect on behavior, appetite, or fertility. In contrast, tonometrically measured intraocular pressure was significantly elevated by approximately 4 mmHg in PM/PGFS KO mice compared to littermate WT mice. Outflow facility was measured in enucleated mouse eyes using the iPerfusion system. No effect on pressure dependent outflow facility occurred, which is consistent with the effects of prostamide F_2α and PGF_2α increasing outflow through the unconventional pathway. The elevation of intraocular pressure caused by deletion of the gene encoding the PM/PGFS enzyme likely results from a diversion of the endoperoxide precursor pathway to provide increased levels of those prostanoids known to raise intraocular pressure, namely prostaglandin D₂ (PGD₂) and thromboxane A₂ (TxA₂). It follows that PM/PGFS may serve an important regulatory role in the eye by providing PGF_2α and prostamide F_2α to constrain the influence of those prostanoids that raise intraocular pressure.

15-keto-prostaglandin E2 activates host peroxisome proliferator-activated receptor gamma (PPAR-γ) to promote Cryptococcus neoformans growth during infection

Cryptococcus neoformans is one of the leading causes of invasive fungal infection in humans worldwide. C. neoformans uses macrophages as a proliferative niche to increase infective burden and avoid immune surveillance. However, the specific mechanisms by which C. neoformans manipulates host immunity to promote its growth during infection remain ill-defined. Here we demonstrate that eicosanoid lipid mediators manipulated and/or produced by C. neoformans play a key role in regulating pathogenesis. C. neoformans is known to secrete several eicosanoids that are highly similar to those found in vertebrate hosts. Using eicosanoid deficient cryptococcal mutants Δplb1 and Δlac1, we demonstrate that prostaglandin E₂ is required by C. neoformans for proliferation within macrophages and in vivo during infection. Genetic and pharmacological disruption of host PGE₂ synthesis is not required for promotion of cryptococcal growth by eicosanoid production. We find that PGE₂ must be dehydrogenated into 15-keto-PGE₂ to promote fungal growth, a finding that implicated the host nuclear receptor PPAR-γ. C. neoformans infection of macrophages activates host PPAR-γ and its inhibition is sufficient to abrogate the effect of 15-keto-PGE₂ in promoting fungal growth during infection. Thus, we describe the first mechanism of reliance on pathogen-derived eicosanoids in fungal pathogenesis and the specific role of 15-keto-PGE₂ and host PPAR-γ in cryptococcosis.

Cryptococcus neoformans is an opportunistic fungal pathogen that is responsible for significant numbers of deaths in the immunocompromised population worldwide. Here we address whether eicosanoids produced by C. neoformans manipulate host innate immune cells during infection. Cryptococcus neoformans produces several eicosanoids that are notable for their similarity to vertebrate eicosanoids, it is therefore possible that fungal-derived eicosanoids may provoke physiological effects in the host. Using a combination of in vitro and in vivo infection models we identify a specific eicosanoid species—prostaglandin E2 –that is required by C. neoformans for growth during infection. We subsequently show that prostaglandin E₂ must be converted to 15-keto-prostaglandin E₂ within the host before it has these effects. Furthermore, we find that prostaglandin E₂/15-keto-prostaglandin E₂ mediated virulence is via activation of host PPAR-γ –an intracellular eicosanoid receptor known to interact with 15-keto-PGE₂.

Rabbit plasma metabolomic analysis of Nitroproston®: a multi target natural prostaglandin based-drug

INTRODUCTION

Nitroproston® is a novel multi-target drug bearing natural prostaglandin E₂ (PGE₂) and nitric oxide (NO)-donating fragments for treatment of inflammatory and obstructive diseases (i.e., asthma and obstructive bronchitis).

OBJECTIVES

To investigate the effects of Nitroproston® administration on plasma metabolomics in vivo.

METHODS

Experimental in vivo study randomly assigning the target drug (treatment group) or a saline solution without the drug (vehicle control group) to 12 rabbits (n = 6 in each group). Untargeted (5880 initial features; 1869 negative-4011 positive ion peaks; UPLC-IT-TOF/MS) and 84 targeted moieties (Nitroproston® related metabolites, prostaglandins, steroids, purines, pyrimidines and amino acids; HPLC-QQQ-MS/MS) were measured from plasma at 0, 2, 4, 6, 8, 12, 18, 24, 32 and 60 min after administration.

RESULTS

PGE₂, 13,14-dihydro-15-keto-PGE₂, PGB₂, 1,3-GDN and 15-keto-PGE₂ increased in the treatment group. Steroids (i.e., cortisone, progesterone), organic acids, 3-oxododecanoic acid, nicotinate D-ribonucleoside, thymidine, the amino acids serine and aspartate, and derivatives pyridinoline, aminoadipic acid and uric acid increased (p < 0.05 AUCROC curve > 0.75) after treatment. Purines (i.e., xanthine, guanine, guanosine), bile acids, acylcarnitines and the amino acids L-tryptophan and L-phenylalanine were decreased. Nitroproston® impacted steroidogenesis, purine metabolism and ammonia recycling pathways, among others.

CONCLUSION

Nitroproston®, a multi action novel drug based on natural prostaglandins, altered metabolites (i.e., guanine, adenine, cortisol, cortisone and aspartate) involved in purine metabolism, urea and ammonia biological cycles, steroidogenesis, among other pathways. Suggested mechanisms of action, metabolic pathway interconnections and useful information to further understand the metabolic effects of prostaglandin administration are presented.

Targeting the 15-keto-PGE2-PTGR2 axis modulates systemic inflammation and survival in experimental sepsis

Sepsis is a systemic inflammation accompanied by multi-organ dysfunction due to microbial infection. Prostaglandins and their metabolites have long been studied for their importance in regulating the innate immune response. 15-keto-PGE2 (15k-PGE₂) is a prostaglandin E2 (PGE₂) metabolite, whose further processing is catalyzed by prostaglandin reductase 2 (PTGR2). We showed disruption of the Ptgr2 gene in mice improves the survival rate under both LPS- and cecum ligation/puncture (CLP)-induced experimental sepsis. Knockdown of PTGR2 showed significant accumulation of intracellular 15k-PGE₂ in activated macrophages. Both PTGR2 knockdown and exogenous treatment with 15k-PGE₂ resulted in reduced pro-inflammatory cytokines production in LPS-stimulated RAW264.7 cells or bone marrow-derived macrophages (BMDM). The same treatment in RAW264.7 and BMDM also led to increased levels of the anti-oxidative transcription factor, Nuclear factor (erythroid-2) related factor-2 (NRF2), augmented anti-oxidant response element (ARE)-mediated reporter activity and upregulated expression of the corresponding anti-oxidant genes. 15k-PGE₂ further demonstrated modification to Kelch-like ECH-associated protein 1 (Keap1), a negative regulator of Nrf2, at cysteine 288 (Cys288) site post-translationally. Finally, 15k-PGE₂-treated mice were found to be more resistant to experimental sepsis. Taken together, our study affirms the significance of PTGR2 and 15k-PGE₂ in mitigating inflammatory responses and suggests a novel anti-oxidative and anti-inflammatory therapy for sepsis through targeting PTGR2 and administering15k-PGE₂.

EP2 receptor agonist ONO-AE1-259-01 attenuates pentylenetetrazole- and pilocarpine-induced seizures but causes hippocampal neurotoxicity

Epilepsy is a common and devastating neurological disease affecting more than 50 million people worldwide. Accumulating experimental and clinical evidence suggests that inflammatory pathways contribute to the development of seizures in various forms of epilepsy. In this context, while the activation of the PGE₂ EP2 receptor causes early neuroprotective and late neurotoxic effects, the role of EP2 receptor in seizures remains unclear. We investigated whether the systemic administration of the highly selective EP2 agonist ONO-AE1-259-01 prevented acute pentylenetetrazole (PTZ)- and pilocarpine-induced seizures. The effect of ONO-AE1-259-01 on cell death in the hippocampal formation of adult male mice seven days after pilocarpine-induced status epilepticus (SE) was also evaluated. ONO-AE1-259-01 (10μg/kg, s.c.) attenuated PTZ- and pilocarpine-induced seizures, evidenced by the increased latency to seizures, decreased number and duration of seizures episodes and decreased mean amplitude of electrographic seizures. ONO-AE1-259-01 and pilocarpine alone significantly increased the number of pyknotic cells per se in all hippocampal subfields. The EP2 agonist also additively increased pilocarpine-induced pyknosis in the pyramidal cell layer of CA1 but reduced pilocarpine-induced pyknosis in the granule cell layer of the dentate gyrus (DG). Although the systemic administration of ONO-AE1-259-01 caused a significant anticonvulsant effect in our assays, this EP2 agonist caused extensive cell death. These findings limit the likelihood of EP2 receptor agonists being considered as novel potential anticonvulsant drugs.

Improvement of metabolic disorders by an EP2 receptor agonist via restoration of the subcutaneous adipose tissue in pulmonary emphysema

Chronic obstructive pulmonary disease (COPD) is often associated with co-morbidities. Metabolic disorders like hyperlipidemia and diabetes occur also in underweight COPD patients, although the mechanism is uncertain. Subcutaneous adipose tissue (SAT) plays an important role in energy homeostasis, since restricted capacity to increase fat cell number with increase in fat cell size occurring instead, is associated with lipotoxicity and metabolic disorders. The aim of this study is to show the protective role of SAT for the metabolic disorders in pulmonary emphysema of a murine model. We found ectopic fat accumulation and impaired glucose homeostasis with wasting of SAT in a murine model of elastase-induced pulmonary emphysema (EIE mice) reared on a high-fat diet. ONO-AE1-259, a selective E-prostanoid (EP) 2 receptor agonist, improved angiogenesis and subsequently adipogenesis, and finally improved ectopic fat accumulation and glucose homeostasis with restoration of the capacity for storage of surplus energy in SAT. These results suggest that metabolic disorders like hyperlipidemia and diabetes occured in underweight COPD is partially due to the less capacity for storage of surplus energy in SAT, though the precise mechanism is uncertained. Our data pave the way for the development of therapeutic interventions for metabolic disorders in emphysema patients, e.g., use of pro-angiogenic agents targeting the capacity for storage of surplus energy in the subcutaneous adipose tissue.

15-hydroxyprostaglandin dehydrogenase (15-PGDH) prevents lipopolysaccharide (LPS)-induced acute liver injury

The NAD+-dependent 15-hydroxyprostaglandin dehydrogenase (15-PGDH) catalyzes the oxidation of the 15(S)-hydroxyl group of prostaglandin E₂ (PGE₂), converting the pro-inflammatory PGE₂ to the anti-inflammatory 15-keto-PGE₂ (an endogenous ligand for peroxisome proliferator-activated receptor-gamma [PPAR-γ]). To evaluate the significance of 15-PGDH/15-keto-PGE₂ cascade in liver inflammation and tissue injury, we generated transgenic mice with targeted expression of 15-PGDH in the liver (15-PGDH Tg) and the animals were subjected to lipopolysaccharide (LPS)/Galactosamine (GalN)-induced acute liver inflammation and injury. Compared to the wild type mice, the 15-PGDH Tg mice showed lower levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), less liver tissue damage, less hepatic apoptosis/necrosis, less macrophage activation, and lower inflammatory cytokine production. In cultured Kupffer cells, treatment with 15-keto-PGE₂ or the conditioned medium (CM) from 15-PGDH Tg hepatocyes inhibited LPS-induced cytokine production, in vitro. Both 15-keto-PGE₂ and the CM from15-PGDH Tg hepatocyes also up-regulated the expression of PPAR-γ downstream genes in Kupffer cells. In cultured hepatocytes, 15-keto-PGE₂ treatment or 15-PGDH overexpression did not influence TNF-α-induced hepatocyte apoptosis. These findings suggest that 15-PGDH protects against LPS/GalN-induced liver injury and the effect is mediated via 15-keto-PGE₂, which activates PPAR-γ in Kupffer cells and thus inhibits their ability to produce inflammatory cytokines. Accordingly, we observed that the PPAR-γ antagonist, GW9662, reversed the effect of 15-keto-PGE₂ in Kupffer cell in vitro and restored the susceptibility of 15-PGDH Tg mice to LPS/GalN-induced acute liver injury in vivo. Collectively, our findings suggest that 15-PGDH-derived 15-keto-PGE₂ from hepatocytes is able to activate PPAR-γ and inhibit inflammatory cytokine production in Kupffer cells and that this paracrine mechanism negatively regulates LPS-induced necro-inflammatory response in the liver. Therefore, induction of 15-PGDH expression or utilization of 15-keto-PGE₂ analogue may have therapeutic benefits for the treatment of endotoxin-associated liver inflammation/injury.

Therapeutic effects of human gingiva-derived mesenchymal stromal cells on murine contact hypersensitivity via prostaglandin E2-EP3 signaling

BACKGROUND

The immunomodulatory and anti-inflammatory functions of human gingiva-derived mesenchymal stromal cells (GMSCs) have been demonstrated in contact hypersensitivity (CHS) models; however, their therapeutic effect during the late phase of CHS has been poor.

METHODS

The murine CHS model was induced by applying oxazolone to the ears of mice. Mesenchymal stromal cells were applied via two methods (intravenous or local injection) at three time points: 1 day before sensitization, 1 day before challenge, or 1 h after challenge. Prostaglandin E2 (PGE2) and sulprostone were administered subcutaneously 1 h after challenge.

RESULTS

The application of GMSCs, bone marrow mesenchymal stem cells, and adipose-derived stem cells all effectively suppressed CHS; however, GMSC treatment exhibited the greatest efficacy. Local injection of GMSCs led to a more marked attenuation of CHS compared with intravenous injection, especially during the late phase of CHS, and this manifested as decreased infiltration of inflammatory cells, suppression of the levels of various proinflammatory cytokines, reconstruction of the disrupted Th1/Th2 balance, and upregulation of regulatory T cells in the allergen contact areas. Pretreatment with indomethacin significantly abrogated the GMSC-mediated immunosuppressive effects, while PGE2 application reversed the effects of indomethacin pretreatment of GMSCs. Moreover, GMSC administration promoted the expression of EP3, a prostaglandin E receptor, and the application of sulprostone, an agonist of EP3, significantly attenuated CHS to a similar degree as that of GMSC administration.

CONCLUSIONS

GMSCs have reproducible and powerful immunomodulatory functions. Local injection of GMSCs is the superior mode for therapeutic application. PGE2-EP3 signaling plays an important role in the immunomodulatory functions of GMSCs in murine CHS.

Role of EP2 and EP4 receptors in airway microvascular leak induced by prostaglandin E2

BACKGROUND AND PURPOSE

Airway microvascular leak (MVL) involves the extravasation of proteins from post-capillary venules into surrounding tissue. MVL is a cardinal sign of inflammation and an important feature of airway inflammatory diseases such as asthma. PGE2, a product of COX-mediated metabolism of arachidonic acid, binds to four receptors, termed EP1–4. PGE2 has a wide variety of effects within the airway, including modulation of inflammation, sensory nerve activation and airway tone. However, the effect of PGE2 on airway MVL and the receptor/s that mediate this have not been described.

EXPERIMENTAL APPROACH

Evans Blue dye was used as a marker of airway MVL, and selective EP receptor agonists and antagonists were used alongside EP receptor-deficient mice to define the receptor subtype involved.

KEY RESULTS

PGE2 induced significant airway MVL in mice and guinea pigs. A significant reduction in PGE2-induced MVL was demonstrated in Ptger2−/− and Ptger4−/− mice and in wild-type mice pretreated simultaneously with EP2 (PF-04418948) and EP4 (ER-819762) receptor antagonists. In a model of allergic asthma, an increase in airway levels of PGE2 was associated with a rise in MVL; this change was absent in Ptger2−/− and Ptger4−/− mice.

CONCLUSIONS AND IMPLICATIONS

PGE2 is a key mediator produced by the lung and has widespread effects according to the EP receptor activated. Airway MVL represents a response to injury and under ‘disease’ conditions is a prominent feature of airway inflammation. The data presented highlight a key role for EP2 and EP4 receptors in MVL induced by PGE2.

Recombinant human FVIIa for reducing the need for invasive second-line therapies in severe refractory postpartum hemorrhage: a multicenter, randomized, open controlled trial

BACKGROUND

Case reports on recombinant human factor VIIa (rhuFVIIa) use in women with severe postpartum hemorrhage (PPH) showed encouraging results, but no randomized controlled trial (RCT) is available.

PATIENTS AND METHODS

Eighty-four women with severe PPH unresponsive to uterotonics were randomized to receive one early single rhuFVIIa infusion (n = 42) or standard care (no rhuFVIIa; n = 42). The primary efficacy outcome measure was the reduction of the need for specific second-line therapies, such as interventional hemostatic procedures, for blood loss and transfusions. The primary safety outcome measure was the number of deaths and thrombotic events during the 5 days following rhuFVIIa infusion.

RESULTS

rhuFVIIa was associated with a reduction in the number of patients who needed second-line therapies compared with controls (standard care). Specifically, 39/42 (93%) patients in the standard care arm received second-line therapies and 22/42 (52%) patients in the rhuFVIIa arm (absolute difference, 41%; range, 18-63%; relative risk RR, 0.56 [0.42-0.76]). The delivery mode (vaginal or Cesarean section) did not affect the primary outcome. No death occurred. Two venous thrombotic events were recorded in the rhuFVIIa arm: one ovarian vein thrombosis and one deep vein thrombosis with a non-severe pulmonary embolism.

CONCLUSION

This open RCT in women with severe PPH refractory to uterotonics shows that rhuFVIIa reduces the need for specific second-line therapies in about one in three patients, with the occurrence of non-fatal venous thrombotic events in one in 20 patients.

Promotion of adipogenesis by an EP2 receptor agonist via stimulation of angiogenesis in pulmonary emphysema

Body weight loss is a common manifestation in patients with chronic obstructive pulmonary disease (COPD), particularly those with severe emphysema. Adipose angiogenesis is a key mediator of adipogenesis and use of pro-angiogenic agents may serve as a therapeutic option for lean COPD patients. Since angiogenesis is stimulated by PGE2, we examined whether ONO-AE1-259, a selective E-prostanoid (EP) 2 receptor agonist, might promote adipose angiogenesis and adipogenesis in a murine model of elastase-induced pulmonary emphysema (EIE mice). Mice were intratracheally instilled with elastase or saline, followed after 4 weeks by intraperitoneal administration of ONO-AE1-259 for 4 weeks. The subcutaneous adipose tissue (SAT) weight decreased in the EIE mice, whereas in the EIE mice treated with ONO-AE1-259, the SAT weight was largely restored, which was associated with significant increases in SAT adipogenesis, angiogenesis, and VEGF protein production. In contrast, ONO-AE1-259 administration induced no alteration in the weight of the visceral adipose tissue. These results suggest that in EIE mice, ONO-AE1-259 stimulated adipose angiogenesis possibly via VEGF production, and thence, adipogenesis. Our data pave the way for the development of therapeutic interventions for weight loss in emphysema patients, e.g., use of pro-angiogenic agents targeting the adipose tissue vascular component.

Prostaglandins for management of retained placenta

BACKGROUND

Retained placenta affects 0.5% to 3% of women following delivery and it is a major cause of maternal death due to postpartum haemorrhage. Usually, retained placenta has been managed by manual removal or curettage under anaesthesia, which may be associated with haemorrhage, infection and uterine perforation. Medical management to facilitate the delivery of the retained placenta could be a safe alternative avoiding surgical intervention.

OBJECTIVES

To assess the effectiveness and safety of prostaglandins for the management of retained placenta.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 December 2013), LILACS (1982 to 1 December 2013), SciELO (1998 to 1 December 2013), Web of Science (2001 to 1 December 2013), openSIGLE (1997 to 1 December 2013), World Health Organization International Clinical Trials Registry Platform (ICTRP) (1 December 2013) and the metaRegister of Controlled Trials (mRCT) (1 December 2013). We also contacted authors of included studies and reviewed the reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled clinical trials comparing the use of prostaglandins (or prostaglandin analogues) with placebo, expectant management, tocolytic drugs, any other prostaglandins or surgical interventions for the management of retained placenta after vaginal delivery of singleton live infants of 20 or more weeks of gestation.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and assessed trial quality. Two review authors independently extracted data. Data were checked for accuracy. Any disagreements were resolved through consensus or consultation with a third review author when required. Authors of the included studies were contacted for additional information.

MAIN RESULTS

We included three trials, involving 244 women. The studies were considered to be at high risk of bias.The prostaglandins used were PG E2 analogue (sulprostone) in 50 participants and PG E1 analogue (misoprostol) in 194 participants at a dose of 250 mcg and 800 mcg respectively. The prostaglandins compared with placebo, were not superior in reducing the rate of manual removal of placenta (average risk ratio (RR) 0.82; 95% confidence interval (CI) 0.54 to 1.27), severe postpartum haemorrhage (RR 0.80; 95% CI 0.55 to 1.15), need for blood transfusion (RR 0.72; 95% CI 0.43 to 1.22), mean blood loss (mean difference (MD) -205.26 mL; 95% CI -536.31 to 125.79, random-effects) and the mean time from injection to placental removal (MD -7.00 minutes; 95% CI -21.20 to 7.20). Side-effects were no different between groups (vomiting, headache, pain and nausea between injection and discharge from the labour ward), with the exception of shivering, which was more frequent in women receiving prostaglandins (RR 10.00; 95% CI 1.40 to 71.49). We did not obtain any data for the primary outcomes of maternal mortality and the need to add another therapeutic uterotonic.

AUTHORS' CONCLUSIONS

Currently there is limited, very low-quality evidence relating to the effectiveness and the safety using prostaglandins for the management of retained placenta. Use of prostaglandins resulted in less need for manual removal of placenta, severe postpartum haemorrhage and blood transfusion but none of the differences reached statistical significance. Much larger, adequately powered studies are needed to confirm that these clinically important beneficial effects are not just chance findings.Similarly, no differences were detected between prostaglandins and placebo in mean blood loss or the mean time from injection to placental removal (minutes) or side-effects (vomiting, headache, pain and nausea between injection and discharge from the labour ward) except for 'shivering' which was more frequent in women who received prostaglandin. The included studies were of poor quality and there is little confidence in the effect estimates; the true effect is likely to be substantially different. We can not make any recommendations about changes to clinical practice. More high-quality research in this area is needed.

Prostaglandin E2 regulates its own inactivating enzyme, 15-PGDH, by EP2 receptor-mediated cervical cell-specific mechanisms

CONTEXT

Prostaglandins play important roles in parturition and have been used to induce cervical ripening and labor. Prior to cervical ripening at term, 15-hydroxyprostaglandin dehydrogenase (15-PGDH) is highly expressed in the cervix and metabolizes cyclooxygenase-2-mediated increases in active prostaglandin E2 (PGE2) to inactive 15-keto PGE2. At term, 15-PGDH gene expression decreases and PGE2 accumulates, leading to cervical ripening and labor. Previously, we found that the cervical isoform of microphthalmia-associated transcription factor (MiTF-CX) serves as a progestational transcription factor that represses IL-8 and hypoxia-mediated increases in cyclooxygenase-2.

OBJECTIVE

We tested the hypothesis that PGE2 regulates its own inactivation through MiTF-CX.

DESIGN

We used human cervical stromal cells to investigate the regulation of 15-PGDH.

SETTING

This was a laboratory-based study using cells from clinical tissue samples.

MAIN OUTCOME MEASURES

We evaluated the mechanisms by which PGE2 regulates 15-PGDH in human cervical stromal cells.

RESULTS

PGE2 repressed MiTF-CX and 15-PGDH, whereas ectopic overexpression of MiTF-CX induced 15-PGDH expression levels. Stabilization of HIF-1α by deferoxamine resulted in concomitant down-regulation of MiTF-CX and 15-PGDH. Ectopic overexpression of MiTF-CX abrogated PGE2- and deferoxamine-mediated loss of MiTF-CX and 15-PGDH. PGE2-induced loss of MiTF-CX and 15-PGDH was mediated through prostaglandin E2 receptor (EP2) receptors (PTGER2), but not cAMP.

CONCLUSIONS

The 15-PGDH gene is a MiTF-CX target gene in cervical stromal cells and is down-regulated by PGE2 through EP2 receptors. The findings suggest that EP2 receptor-specific antagonists may be used as an adjunct to present clinical management for the prevention of preterm cervical ripening and preterm labor.

Prostamide F(2) α receptor antagonism combined with inhibition of FAAH may block the pro-inflammatory mediators formed following selective FAAH inhibition

BACKGROUND AND PURPOSE

Prostamides are lipid mediators formed by COX-2-catalysed oxidation of the endocannabinoid anandamide and eliciting effects often opposed to those caused by anandamide. Prostamides may be formed when hydrolysis of anandamide by fatty acid amide hydrolase (FAAH) is physiologically, pathologically or pharmacologically decreased. Thus, therapeutic benefits of FAAH inhibitors might be attenuated by concomitant production of prostamide F2 α . This loss of benefit might be minimized by compounds designed to selectively antagonize prostamide receptors and also inhibiting FAAH.

EXPERIMENTAL APPROACH

Inhibition of FAAH by a series of selective antagonists of prostamide receptors, including AGN 204396, AGN 211335 and AGN 211336, was assessed using rat, mouse and human FAAH in vitro, together with affinity for human recombinant CB1 and CB2 receptors. Effects in vivo were measured in a model of formalin-induced inflammatory pain in mice.

KEY RESULTS

The prostamide F2 α receptor antagonists were active against mouse and rat FAAH in the low μM range and behaved as non-competitive and plasma membrane-permeant inhibitors. AGN 211335, the most potent inhibitor of rat FAAH (IC50  = 1.2 μM), raised exogenous anandamide levels in intact cells and also bound to cannabinoid CB1 receptors. Both AGN 211335 and AGN 211336 (0.25-1 mg·kg(-1) , i.p.) inhibited the formalin-induced nociceptive response in mice.

CONCLUSIONS AND IMPLICATIONS

Synthetic compounds with indirect agonist activity at cannabinoid receptors and antagonist activity at prostamide receptors can be developed. Such compounds could be used as alternatives to selective FAAH inhibitors to prevent the possibility of prostamide F2 α -induced inflammation and pain.

LINKED ARTICLES

This article is part of a themed section on Cannabinoids 2013. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-6.

Role of PGE2 in the colonic motility: PGE2 generates and enhances spontaneous contractions of longitudinal smooth muscle in the rat colon

The aim of this study was to determine which PGE2 receptors (EP1-4 receptors) influence colonic motility. Mucosa-free longitudinal smooth muscle strips of the rat middle colon spontaneously induced frequent phasic contractions (giant contractions, GCs) in vitro, and the GCs were almost completely abolished by a cyclooxygenase inhibitor, piroxicam, and by an EP3 receptor antagonist, ONO-AE3-240, but enhanced by tetrodotoxin (TTX). In the presence of piroxicam, exogenous PGE2, both ONO-AE-248 (EP3 agonist), and ONO-DI-004 (EP1 agonist) induced GC-like contractions, and increased the frequency and amplitude. These effects of EP receptor agonists were insensitive to TTX and ω-conotoxins. In immunohistochemistry, the EP1 and EP3 receptors were expressed in the longitudinal smooth muscle cells. These results suggest that the endogenous PGE2 spontaneously generates and enhances the frequent phasic contractions directly activating the EP1 and EP3 receptors expressed on longitudinal smooth muscle cells in the rat middle colon.

Induction of cervical dilation for transcervical embryo transfer in ewes

BACKGROUND

A major limitation in the application of assisted reproductive technologies in sheep arises from the inability to easily traverse the uterine cervix. The cervix of the non-pregnant ewe is a narrow and rigid structure, with 5-7 spiral folds and crypts that block its lumen. The first two folds closest to the vagina appear to be the greatest obstacle for the instrument insertion into the sheep cervix. Therefore, the dilation of the distal part of the cervix could provide the conformational change necessary to perform non-invasive transcervical procedures. The present study set out to assess the efficacy of Cervidil®, a patented dinoprostone (PgE2)-containing vaginal insert with a controlled-release mechanism, to safely induce sufficient cervical dilation for the purpose of transcervical embryo transfer (TCET) in cyclic ewes.

METHODS

The transfer of frozen-thawed ovine embryos was attempted in 22 cross-bred Rideau Arcott x Polled Dorset ewes, with or without the pre-treatment with Cervidil® for 12 or 24 h prior to TCET.

RESULTS

Cervical penetration rate was significantly improved after Cervidil® pre-treatment, with 55% (6/11) of treated versus 9% (1/11) of control animals successfully penetrated (χ2-test, p < 0.05). Within the treated ewes that were penetrated, 67% (4/6) had been exposed to Cervidil(R) for 24 h and 33% (2/6) had had a 12-h exposure (p > 0.05). Variations in the age, weight, genotype, parity, lifetime lamb production (LLP) and post-partum interval (PPI) between penetrated and non-penetrated ewes were not significant (p > 0.05). The time taken to traverse the uterine cervix was negatively correlated (p < 0.05) with the age, parity, LLP and PPI. Progesterone assays and ultrasonographic examinations performed 25 days after ET confirmed pregnancy in 2 of 7 penetrated ewes, but no fetuses were detected ultrasonographically 55 days post-TCET.

CONCLUSIONS

The present results indicate a significant benefit of using Cervidil® for inducing cervical dilation during the mid-luteal phase in ewes but the reason(s) for impaired fertility after the transfer of frozen-thawed ovine embryos remains to be elucidated.

Sulprostone for postpartum hemorrhage in a parturient with a history of Tako-tsubo cardiomyopathy

A 32 year old parturient with a history of Tako-tsubo cardiomyopathy, who suffered from postpartum hemorrhage for which sulprostone was administered without any adverse events, is reported. Anesthetic considerations related to the management of patient with a history of Tako-tsubo cardiomyopathy, especially triggers that may cause a recurrence, are described. The potential deleterious effects of sulprostone in a patient with a history of Tako-tsubo cardiomyopathy are discussed.

Nature of the slow relaxation of smooth muscle induced by a EP2 receptor agonist with a non-prostanoid structure

The remarkably slow onset/offset of relaxation of guinea-pig isolated trachea induced by a 'non-prostanoid' EP2 receptor agonist, (o-(o-benzyloxy)-cinnamyl)-cinnamic acid (coded (L)-9), was investigated. (L)-9 kinetics was slightly faster on mouse trachea and considerably faster on rabbit vena cava. In each case, reversal of (L)-9 relaxation by the selective EP2 antagonist ACA-23 was rapid and similar to other EP2 agonists (e.g. ONO-AE1-259). On guinea-pig aorta, in the presence of extensive EP2 receptor blockade, (L)-9 inhibited TP agonist-induced contraction more slowly than TP antagonists of similar affinity. The slower kinetics of (L)-9 appear to correlate with greater adventitial/submucosal barriers and thicker smooth muscle layers in the tissues examined. It is proposed that interactions of (L)-9 with EP2 and TP receptors are not rate-limiting, rather diffusion to and from the centre of the muscle mass is retarded by the high lipophilicity of (L)-9 (logP=6.69; ONO-AE1-259=3.95).

Gastric cytoprotection beyond prostaglandins: cellular and molecular mechanisms of gastroprotective and ulcer healing actions of antacids

This article updates current views on gastric mucosal defense, injury, protection and ulcer healing with a focus on mucosal protective and ulcer healing actions of antacids. The gastric mucosa is continuously exposed to a variety of noxious factors, both endogenous such as: 0.1N hydrochloric acid, pepsin, bile acids, lysolecithin, H. pylori toxins and exogenous such as NSAIDs, ethanol and others. Gastric mucosal integrity is maintained by pre-epithelial, epithelial and post-epithelial defense mechanisms permitting the mucosa to withstand exposure to the above damaging factors. When mucosal defense is weakened or overwhelmed by injurious factors, injury develops in the form of erosions or ulcers. In the late 1970s Andre Robert and coworkers discovered that microgram amounts of a prostaglandin E2 analog protects the gastric mucosa against a variety of ulcerogenic and necrotizing agents - even such strong inducers of injury as 100% ethanol and boiling water. They proposed a new concept of cytoprotection. Subsequently, other compounds, such as sulfhydryls, sucralfate and epidermal growth factor were shown to exert protective action on gastric mucosa. Additionally, some antacids have been shown to exert a potent mucosal protective action against a variety of injurious factors and accelerate healing of erosions and gastric ulcers. These actions of antacids, especially hydrotalcite - the newest and the most extensively studied antacid - are due to activation of prostaglandin synthesis; binding to and inactivation of pepsin, bile acids and H. pylori toxins; induction of heat shock proteins; and, activation of genes encoding growth factors and their receptors.

Gastric cytoprotection beyond prostaglandins: cellular and molecular mechanisms of gastroprotective and ulcer healing actions of antacids

This article updates current views on gastric mucosal defense, injury, protection and ulcer healing with a focus on mucosal protective and ulcer healing actions of antacids. The gastric mucosa is continuously exposed to a variety of noxious factors, both endogenous such as: 0.1N hydrochloric acid, pepsin, bile acids, lysolecithin, H. pylori toxins and exogenous such as NSAIDs, ethanol and others. Gastric mucosal integrity is maintained by pre-epithelial, epithelial and post-epithelial defense mechanisms permitting the mucosa to withstand exposure to the above damaging factors. When mucosal defense is weakened or overwhelmed by injurious factors, injury develops in the form of erosions or ulcers. In the late 1970s Andre Robert and coworkers discovered that microgram amounts of a prostaglandin E2 analog protects the gastric mucosa against a variety of ulcerogenic and necrotizing agents - even such strong inducers of injury as 100% ethanol and boiling water. They proposed a new concept of cytoprotection. Subsequently, other compounds, such as sulfhydryls, sucralfate and epidermal growth factor were shown to exert protective action on gastric mucosa. Additionally, some antacids have been shown to exert a potent mucosal protective action against a variety of injurious factors and accelerate healing of erosions and gastric ulcers. These actions of antacids, especially hydrotalcite - the newest and the most extensively studied antacid - are due to activation of prostaglandin synthesis; binding to and inactivation of pepsin, bile acids and H. pylori toxins; induction of heat shock proteins; and, activation of genes encoding growth factors and their receptors.

Prostanoid receptors involved in regulation of the beating rate of neonatal rat cardiomyocytes

Although prostanoids are known to be involved in regulation of the spontaneous beating rate of cultured neonatal rat cardiomyocytes, the various subtypes of prostanoid receptors have not been investigated in detail. In our experiments, prostaglandin (PG)F_2α and prostanoid FP receptor agonists (fluprostenol, latanoprost and cloprostenol) produced a decrease in the beating rate. Two prostanoid IP receptor agonists (iloprost and beraprost) induced first a marked drop in the beating rate and then definitive abrogation of beating. In contrast, the prostanoid DP receptor agonists (PGD₂ and BW245C) and TP receptor agonists (U-46619) produced increases in the beating rate. Sulprostone (a prostanoid EP₁ and EP₃ receptor agonist) induced marked increases in the beating rate, which were suppressed by SC-19220 (a selective prostanoid EP₁ antagonist). Butaprost (a selective prostanoid EP₂ receptor agonist), misoprostol (a prostanoid EP₂ and EP₃ receptor agonist), 11-deoxy-PGE₁ (a prostanoid EP₂, EP₃ and EP₄ receptor agonist) did not alter the beating rate. Our results strongly suggest that prostanoid EP₁ receptors are involved in positive regulation of the beating rate. Prostanoid EP₁ receptor expression was confirmed by western blotting with a selective antibody. Hence, neonatal rat cardiomyocytes express both prostanoid IP and FP receptors (which negatively regulate the spontaneous beating rate) and prostanoid TP, DP₁ and EP₁ receptors (which positively regulate the spontaneous beating rate).

[Severe hyperthermia and neurological disorders following prostaglandin treatment for uterine atonia after caesarean section]

Uterine atony is the most frequent cause of post-partum haemorrhage. In France, the management is based on early administration of oxytocic agents and prostaglandin analogues (sulprostone-Nalador®). We report the case of a 30-year-old woman who presented soon after administration of sulprostone, a severe hyperthermia with neurological disorders. A complete reversibility was observed a few hours after discontinuation of sulprostone administration. Other causes were eliminated by biological and radiological findings.

Discovery of prostamide F2α and its role in inflammatory pain and dorsal horn nociceptive neuron hyperexcitability

It was suggested that endocannabinoids are metabolized by cyclooxygenase (COX)-2 in the spinal cord of rats with kaolin/λ-carrageenan-induced knee inflammation, and that this mechanism contributes to the analgesic effects of COX-2 inhibitors in this experimental model. We report the development of a specific method for the identification of endocannabinoid COX-2 metabolites, its application to measure the levels of these compounds in tissues, and the finding of prostamide F_2α (PMF_2α) in mice with knee inflammation. Whereas the levels of spinal endocannabinoids were not significantly altered by kaolin/λ-carrageenan-induced knee inflammation, those of the COX-2 metabolite of AEA, PMF_2α, were strongly elevated. The formation of PMF_2α was reduced by indomethacin (a non-selective COX inhibitor), NS-398 (a selective COX-2 inhibitor) and SC-560 (a selective COX-1 inhibitor). In healthy mice, spinal application of PMF_2α increased the firing of nociceptive (NS) neurons, and correspondingly reduced the threshold of paw withdrawal latency (PWL). These effects were attenuated by the PMF_2α receptor antagonist AGN211336, but not by the FP receptor antagonist AL8810. Also prostaglandin F_2α increased NS neuron firing and reduced the threshold of PWL in healthy mice, and these effects were antagonized by AL8810, and not by AGN211336. In mice with kaolin/λ-carrageenan-induced knee inflammation, AGN211336, but not AL8810, reduced the inflammation-induced NS neuron firing and reduction of PWL. These findings suggest that inflammation-induced, and prostanoid-mediated, enhancement of dorsal horn NS neuron firing stimulates the production of spinal PMF_2α, which in turn contributes to further NS neuron firing and pain transmission by activating specific receptors.

Prostaglandin dehydrogenase (PGDH) in granulosa cells of primate periovulatory follicles is regulated by the ovulatory gonadotropin surge via multiple G proteins

The ovulatory gonadotropin surge increases granulosa cell prostaglandin synthesis as well as prostaglandin dehydrogenase (PGDH), the key enzyme responsible for prostaglandin metabolism. To investigate gonadotropin regulation of PGDH in the primate follicle, monkey granulosa cells were obtained across the 40-h periovulatory interval. PGDH activity was low before the ovulatory hCG stimulus, peaked 12-24 h after hCG, and was low again 36 h after hCG administration. Granulosa cells maintained in vitro with hCG showed a similar temporal pattern of PGDH. The LH/CG receptor can utilize multiple signaling pathways to regulate intracellular events. Gonadotropin-stimulated cAMP appears to act primarily via the Epacs to increase PGDH mRNA, protein, and activity. In contrast, PLC activation of PKC likely decreases PGDH mRNA, protein, and activity late in the periovulatory interval. Increased, then decreased PGDH activity may delay accumulation of prostaglandins in the follicle until late in the periovulatory interval, contributing to timely ovulation in primates.

Mitochondrial fragmentation and superoxide anion production in coronary endothelial cells from a mouse model of type 1 diabetes

AIMS/HYPOTHESIS

Mitochondria frequently change their shapes by fusion and fission and these morphological dynamics play important roles in mitochondrial function and development as well as programmed cell death. The goal of this study is to investigate whether: (1) mitochondria in mouse coronary endothelial cells (MCECs) isolated from diabetic mice exhibit increased fragmentation; and (2) chronic treatment with a superoxide anion (O(2)(-)) scavenger has a beneficial effect on mitochondrial fragmentation in MCECs.

METHODS

MCECs were freshly isolated and lysed for protein measurement, or cultured to determine mitochondrial morphology and O(2)(-) production. For the ex vivo hyperglycaemia experiments, human coronary endothelial cells were used.

RESULTS

Elongated mitochondrial tubules were observed in MCECs isolated from control mice, whereas mitochondria in MCECs from diabetic mice exhibited augmented fragmentation. The level of optic atrophy 1 (OPA1) protein, which leads to mitochondrial fusion, was significantly decreased, while dynamin-related protein 1 (DRP1), which leads to mitochondrial fission, was significantly increased in MCECs from diabetic mice. Diabetic MCECs exhibited significantly higher O(2)(-) concentrations in cytosol and mitochondria than control MCECs. Administration of the O(2)(-) scavenger TEMPOL to diabetic mice for 4 weeks led to a significant decrease in mitochondrial fragmentation without altering the levels of OPA1 and DRP1 proteins in MCECs. High-glucose treatment for 24 h significantly induced mitochondrial fragmentation, which was restored by TEMPOL treatment. In addition, excess O(2)(-) production, either in cytosol or in mitochondria, significantly increased mitochondrial fragmentation.

CONCLUSIONS/INTERPRETATION

These data suggest that lowering the O(2)(-) concentration can restore the morphological change in mitochondria and may help improve mitochondrial function in diabetic MCECs.

Differential regulation of the aggressive phenotype of inflammatory breast cancer cells by prostanoid receptors EP3 and EP4

BACKGROUND

Although inflammatory breast cancer (IBC) is recognized as the most lethal variant of locally advanced breast cancer, few molecular signatures of IBC have been identified that can be used as targets to develop therapeutics that effectively inhibit the aggressive phenotype displayed by IBC tumors.

METHODS

Real-time polymerase chain reaction analysis, Western blot analysis, modified Boyden chamber invasion assays, vasculogenic mimicry (VM) assays, and gelatin zymography were used in the current studies. Agonists and antagonists of the prostanoid receptors EP3 and EP4 and of EP4 short-hairpin RNA (shRNA) knockdown approaches were used as tools to assess the role of prostanoid receptors EP3 and EP4 in the regulation of specific biologic activities of IBC cells.

RESULTS

The current studies revealed that the IBC breast cancer cell lines SUM149 and SUM190 express high levels of cyclooxygenase-2 messenger RNA and protein, produce abundant levels of prostaglandin E(2), and produce both EP3 and EP4 receptor proteins. Studies using the EP4 antagonist GW627368X and shRNA molecular knockdown approaches revealed a role for EP4 in regulating invasion of IBC cells. EP3, but not EP4, regulated the ability of SUM149 cells to undergo VM, which is the ability to form capillary-like structures, a characteristic exhibited by very aggressive tumor types. Inhibition of VM by sulprostone was associated with an inhibition of matrix metalloprotease-2 (MMP-2) enzyme activity.

CONCLUSIONS

The prostanoid receptors EP3 and EP4 differentially regulate activities exhibited by IBC cells that have been associated with the aggressive phenotype of this lethal variant of breast cancer. Whereas EP4 regulates invasion, EP3 regulates VM and the associated increased MMP-2 enzyme activity.

Pharmacological correction of a defect in PPAR-gamma signaling ameliorates disease severity in Cftr-deficient mice

Cystic fibrosis is caused by mutations in the cystic fibrosis transmembrane conductance regulator (encoded by Cftr) that impair its role as an apical chloride channel that supports bicarbonate transport. Individuals with cystic fibrosis show retained, thickened mucus that plugs airways and obstructs luminal organs as well as numerous other abnormalities that include inflammation of affected organs, alterations in lipid metabolism and insulin resistance. Here we show that colonic epithelial cells and whole lung tissue from Cftr-deficient mice show a defect in peroxisome proliferator-activated receptor-gamma (PPAR-gamma, encoded by Pparg) function that contributes to a pathological program of gene expression. Lipidomic analysis of colonic epithelial cells suggests that this defect results in part from reduced amounts of the endogenous PPAR-gamma ligand 15-keto-prostaglandin E(2) (15-keto-PGE(2)). Treatment of Cftr-deficient mice with the synthetic PPAR-gamma ligand rosiglitazone partially normalizes the altered gene expression pattern associated with Cftr deficiency and reduces disease severity. Rosiglitazone has no effect on chloride secretion in the colon, but it increases expression of the genes encoding carbonic anhydrases 4 and 2 (Car4 and Car2), increases bicarbonate secretion and reduces mucus retention. These studies reveal a reversible defect in PPAR-gamma signaling in Cftr-deficient cells that can be pharmacologically corrected to ameliorate the severity of the cystic fibrosis phenotype in mice.

Cervical preparation for first trimester surgical abortion

BACKGROUND

Preparing the cervix prior to surgical abortion is intended to make the procedure both easier and safer. Options for cervical preparation include osmotic dilators and pharmacologic agents. Many formulations and regimens are available, and recommendations from professional organizations vary for the use of preparatory techniques in women of different ages, parity or gestational age of the pregnancy.

OBJECTIVES

To determine whether cervical preparation is necessary in the first trimester, and if so, which preparatory agent is preferred.

SEARCH STRATEGY

We searched Cochrane, Popline, Embase, Medline and Lilacs databases for randomised controlled trials investigating the use of cervical preparatory techniques prior to first trimester surgical abortion. In addition, we hand-searched key references and contacted authors to locate unpublished studies or studies not identified in the database searches.

SELECTION CRITERIA

Randomised controlled trials investigating any pharmacologic or mechanical method of cervical preparation, with the exception of nitric oxide donors (the subject of another Cochrane review), administered prior to first trimester surgical abortion were included. Outcome measures must have included the amount of cervical dilation achieved, the procedure duration or difficulty, side-effects, patient satisfaction or adverse events to be included in this review.

DATA COLLECTION AND ANALYSIS

Trials under consideration were evaluated by considering whether inclusion criteria were met as well as methodologic quality. Fifty-one studies were included, resulting in 24 different cervical preparation comparisons. Results are reported as odds ratios (OR) for dichotomous outcomes and weighted mean differences for continuous data.

MAIN RESULTS

When compared to placebo, misoprostol (400-600 microg given vaginally or sublingually), gemeprost, mifepristone (200 or 600 mg), prostaglandin E and F(2alpha) (2.5 mg administered intracervically) demonstrated larger cervical preparation effects. When misoprostol was compared to gemeprost, misoprostol was more effective in preparing the cervix and was associated with fewer gastrointestinal side-effects. For vaginal administration, administration 2 hours prior was less effective than administration 3 hours prior to the abortion. Compared to oral misoprostol administration, the vaginal route was associated with significantly greater initial cervical dilation and lower rates of side-effects; however, sublingual administration 2-3 hours prior to the procedure demonstrated cervical effects superior to vaginal administration.When misoprostol (600 microg oral or 800 microg vaginal) was compared to mifepristone (200 mg administered 24 hours prior to procedure), misoprostol had inferior cervical preparatory effects. Compared to day-prior laminaria tents, 200 or 400 microg vaginal misoprostol showed no differences in the need for further mechanical dilation or length of the procedure; similarly, the osmotic dilators Lamicel and Dilapan showed no differences in cervical ripening when compared to gemeprost, although gemeprost had cervical effects which were superior to laminaria tents. Older prostaglandin regimens (sulprostone, prostaglandin E(2) andF(2alpha)) were associated with high rates of gastrointestinal side-effects and unplanned pregnancy expulsions. Few studies reported women's satisfaction with cervical preparatory techniques.

AUTHORS' CONCLUSIONS

Modern methods of cervical ripening are generally safe, although efficacy and side-effects between methods vary. Reports of adverse events such as cervical laceration or uterine perforation are uncommon overall in this body of evidence and no published study has investigated whether cervical preparation impacts these rare outcomes. Cervical preparation decreases the length of the abortion procedure; this may become increasingly important with increasing gestational age, as mechanical dilation at later gestational ages takes longer and becomes more difficult. These data do not suggest a gestational age where the benefits of cervical dilation outweigh the side-effects, including pain, that women experience with cervical ripening procedures or the prolongation of the time interval before procedure completion. Mifepristone 200 mg, osmotic dilators and misoprostol, 400microg administered either vaginally or sublingually, are the most effective methods of cervical preparation.

Marginal zinc deficiency increases magnesium retention and impairs calcium utilization in rats

An experiment with rats was conducted to determine whether magnesium retention is increased and calcium utilization is altered by a marginal zinc deficiency and whether increased oxidative stress induced by a marginal copper deficiency exacerbated responses to a marginal zinc deficiency. Weanling rats were assigned to six groups of ten with dietary treatment variables of low zinc (5 mg/kg for 2 weeks and 8 mg/kg for 7 weeks), low copper (1.5 mg/kg), adequate zinc (15 mg/kg), and adequate copper (6 mg/kg). Two groups of rats were fed the adequate-zinc diet with low or adequate copper and pair-fed with corresponding rats fed the low-zinc diet. When compared to the pair-fed rats, marginal zinc deficiency significantly decreased the urinary excretion of magnesium and calcium, increased the concentrations of magnesium and calcium in the tibia, increased the concentration of magnesium in the kidney, and increased the urinary excretion of helical peptide (bone breakdown product). Marginal copper deficiency decreased extracellular superoxide dismutase and glutathione, which suggests increased oxidative stress. None of the variables responding to the marginal zinc deficiency were significantly altered by the marginal copper deficiency. The findings in the present experiment suggest that increased magnesium retention and impaired calcium utilization are indicators of marginal zinc deficiency.

Regulation of Nur77 gene expression by prostanoids in cementoblastic cells

OBJECTIVE

The inflammatory cytokine interleukin-1 (IL-1) decreases mineralisation by immortalized mouse-derived cementoblastic cells (OC-CM cells), whilst various prostanoids, including fluprostenol (flup) increase it. Subtraction hybridisation conducted on flup minus IL-1-treated OC-CM cells revealed that one of the primary response genes preferentially induced by flup is the transcription factor Nur77. The objective of this study was to examine the signal transduction cascades regulating prostanoid induction of Nur77 gene expression in OC-CM cells.

METHODS

Confluent OC-CM cells were treated with prostaglandin E(2) (PGE(2)), prostaglandin F(2alpha) (PGF(2alpha)), specific activators of the various EP prostanoid receptors and of the FP prostanoid receptor, and direct activators/inhibitors of the cyclic AMP-protein kinase A (PKA), protein kinase C (PKC) and intracellular calcium pathways. Nur77 gene expression was examined by mRNA extraction and Northern blot analysis.

RESULTS

PGE(2) and PGF(2alpha) treatment of OC-CM cells significantly increased Nur77 mRNA expression in a time- and dose-dependent fashion. Both the EP1 prostanoid receptor-specific activator 16,16-dimethyl-PGE(2) and the FP prostanoid receptor-specific activator flup significantly increased Nur77 gene expression by OC-CM cells as compared to vehicle-treated controls. Increase in Nur77 gene expression was also observed when direct activators of the PKA, PKC and intracellular calcium pathways were used to treat OC-CM cells. Direct inhibition of the PKA, PKC and intracellular calcium pathways abrogated Nur77 gene expression induced by OC-CM cell treatment with PGE(2) and PGF(2alpha).

CONCLUSION

Nur77 is a primary gene expressed by OC-CM cells and its induction appears to be mediated by the PKA, PKC and intracellular calcium pathways. Nur77 may affect expression of downstream target genes in OC-CM cells and partially regulate cementoblast cell function.

Prostaglandin subtype-selective and non-selective IOP-lowering comparison in monkeys

The aim of this study was to determine whether the magnitude of the intraocular-pressure (IOP)-lowering response in monkeys to the nonselective prostaglandin (PG)F(2a)-isopropyl ester (ie) can be reproduced by combining other PG-subtype-selective compounds. IOP was lowered by approximately 25% after 4-5 days of topical administration with latanoprost (FP agonist, 1.5 microg, q.d.), bimatoprost (prostamide, whose metabolites have been shown to be FP agonists; 9 microg, q.d.), or travoprost (FP agonist, 1.2 microg, q.d) or the EP2 agonist, butaprost (25 microg, b.i.d.). The EP1 agonist, 17-phenyl trinor (PhT) PGE2 (b.i.d.), and EP3 agonist, sulprostone (b.i.d.), had no IOP-lowering effects. The addition of butaprost, sulprostone (10 microg), or 17PhTPGE2 (25 microg) to latanoprost did not lower IOP more than latanoprost alone. However, treatment with the combination of latanoprost, 17PhTPGE2, butaprost, and sulprostone produced a similar 50-55% reduction in IOP, as did PGF(2)alpha-ie (b.i.d.). In conclusion, latanoprost, travoprost, and bimatoprost produce similar IOP-lowering responses in normotensive monkeys and are most efficacious when administered q.d. pm, compared to b.i.d. The combination of the FP, EP1, EP2, and EP3 agonists used in this study was sufficient to lower IOP by the same magnitude as PGF(2)alpha-ie, suggesting that combining PG-subtype agonists may be a potent antiglaucoma strategy.

Structural basis for catalytic and inhibitory mechanisms of human prostaglandin reductase PTGR2

PTGR2 catalyzes an NADPH-dependent reduction of the conjugated alpha,beta-unsaturated double bond of 15-keto-PGE(2), a key step in terminal inactivation of prostaglandins and suppression of PPARgamma-mediated adipocyte differentiation. Selective inhibition of PTGR2 may contribute to the improvement of insulin sensitivity with fewer side effects. PTGR2 belongs to the medium-chain dehydrogenase/reductase superfamily. The crystal structures reported here reveal features of the NADPH binding-induced conformational change in a LID motif and a polyproline type II helix which are critical for the reaction. Mutation of Tyr64 and Tyr259 significantly reduces the rate of catalysis but increases the affinity to substrate, confirming the structural observations. Besides targeting cyclooxygenase, indomethacin also inhibits PTGR2 with a binding mode similar to that of 15-keto-PGE(2). The LID motif becomes highly disordered upon the binding of indomethacin, indicating plasticity of the active site. This study has implications for the rational design of inhibitors of PTGR2.

[Termination of pregnancy in the 2nd trimester: mifepriston/misoprostol preferable to sulprostone]

OBJECTIVE

To compare the efficacy of sulprostone and mifepristone/misoprostol when used for termination of pregnancy (TOP) in the 2nd trimester.

DESIGN

Comparative retrospective cohort study.

METHOD

Data were collected on all women whose pregnancies were terminated in the 2nd trimester, in the presence of severe fetal defects, between 1996 and 2007 at the Radboud University Nijmegen Medical Centre, the Netherlands. From the start of 1996 until the end of 2001 TOPs were performed using sulprostone. In 2001 the treatment was switched to the combination mifepristone/misoprostol. The primary outcome measure was the time interval between the initiation of prostaglandin medication and the birth of the infant.

RESULTS

158 patients met the inclusion criteria: 51 women were treated with sulprostone, 107 women with mifepriston/misoprostol. The duration of treatment in the mifepristone/misoprostol group (median 8.7 hours, range: 1.1-72.0 hours) was significantly shorter than in the sulprostone group (median 21.3 hours, range: 7.8-265.0 hours). In the mifepristone/misoprostol group significantly more women (94%) delivered within 24 hours than in the sulprostone group (55%). In the mifepristone/misoprostol group anti-emetics and pain relief were given significantly less often than in the sulprostone group 5 versus 12% and 54 versus 90%, respectively). There was no statistically significant difference in the number of women with post partum blood loss (6 versus 6%), (suspected) placental remnants (33 versus 43%) or fever (12 versus 4%).

CONCLUSION

In termination of pregnancy in the 2nd trimester mifepristone/misoprostol was more effective than sulprostone. Given the disadvantages of sulprostone in comparison with mifepristone/misoprostol, sulprostone no longer deserves a place in termination of pregnancy in the 2nd trimester.

Detection of P2Y(14) protein in platelets and investigation of the role of P2Y(14) in platelet function in comparison with the EP(3) receptor

mRNA encoding the recently discovered P2Y(14) receptor has been reported in platelets, but the presence of P2Y(14) receptor protein and its functionality have not been studied. If P2Y(14) is expressed along with P2Y(1) and P2Y(12) receptors it may have a role in haemostasis. It was the objective of this study to investigate the presence of the P2Y(14) receptor in platelets and its role in platelet function. The effects of the agonist UDP-glucose were compared with those of sulprostone, a selective EP(3) receptor agonist. Expression of P2Y(14) receptor was investigated by immunoblotting and confocal microscopy. Platelet aggregation in platelet-rich plasma (PRP) and whole blood was measured using light absorbance and platelet counting. VASP phosphorylation was investigated using flow cytometry. Immunoblotting provided evidence for P2Y(14) receptor protein and microscopy confirmed its presence on platelets. Despite this, UDP-glucose (up to 100 muM) did not induce platelet aggregation in either PRP or whole blood, and did not potentiate aggregation induced by other agonists. P2Y(14) did not substitute for P2Y(12) in experiments using the P2Y(12) antagonist AR-C69931. No effect of UDP-glucose was seen on adenylate cyclase activity as measured by VASP phosphorylation. In contrast, sulprostone acting via the EP(3) receptor promoted platelet aggregation with effects on adenylate cyclase activity. EP(3) also partially substituted for P2Y(12) receptor. We have demonstrated the presence of P2Y(14) receptor protein in platelets, but no contribution of this receptor to several measures of platelet function has been observed. Further studies are necessary to determine whether the P2Y(14) receptor in platelets has any functionality.

8-iso-PGE2Stimulates Anion Efflux from Airway Epithelial Cells via the EP4Prostanoid Receptor

Isoprostanes are biologically active molecules, produced when reactive oxygen species mediate the peroxidation of membrane polyunsaturated fatty acids. Previous work has demonstrated that the isoprostane 8-iso-prostaglandin E(2) (PGE(2)) stimulates cystic fibrosis transmembrane conductance regulator (CFTR)-mediated transepithelial anion secretion across the human airway epithelial cell line, Calu-3. Since isoprostanes predominantly achieve their effects via binding to prostanoid receptors, we hypothesized that this 8-iso-PGE(2) stimulation of CFTR activity was the result of the isoprostane binding to a prostanoid receptor. Using RT-PCR, immunoblotting, and immunofluorescence, we here demonstrate that Calu-3 cells express the EP(1-4) and FP receptors, and localize these proteins in polarized cell monolayers. Using iodide efflux as a marker for CFTR-mediated Cl(-) efflux, we investigate whether prostanoid receptor agonists elicit a functional response from Calu-3 cells. Application of the agonists PGE(2), misoprostol (EP(2), EP(3), and EP(4)) and PGE(1)-OH (EP(3) and EP(4)) stimulate iodide efflux; however, iloprost, butaprost, sulprostone, and fluoprostenol (agonists of the EP(1), EP(2), EP(3), and FP receptors, respectively) have no effect. The iodide efflux seen with 8-iso-PGE(2) is abolished by the EP(4) receptor antagonist AH23848, the CFTR inhibitor 172, and inhibition of PKA and the PI3K pathway. In conclusion, we demonstrate that although Calu-3 cells possess numerous prostanoid receptors, only the EP(4) subtype appears capable of eliciting a functional iodide efflux response, which is mediated via the EP(4) receptor. We propose that 8-iso-PGE(2), acting via EP(4) receptor, could play an important role in the CFTR-mediated response to oxidant stress, and which would be compromised in the CF airways.

Mitochondria play a role in the development of non-apoptotic programmed cell death of neutrophils induced by ONO-AE-248

We previously reported that ONO-AE-248, a selective EP3 receptor agonist, has been shown to cause neutrophil death without the typical features of apoptosis and necrosis. However, the mechanism of the neutrophil death is unclear. By using Western blotting, flow cytometry (FACS) and confocal laser scanning microscopy (CLSM), we investigated the cellular signal transduction pathways of the neutrophil death. The research results showed that the neutrophil death induced by ONO-AE-248 did not show the morphologic changes of apoptosis and was not associated with the activity of caspase-3, caspase-8, and phosphorylation of p38-MAPK. However, impairment of mitochondria transmembrane potential has been found during the process of cell death. These findings suggested that ONO-AE-248 induced a non-apoptotic programmed cell death of neutrophils through partially mitochondria signaling transduction pathway.

Comparaison historique de deux types de prises en charge de placenta accreta: radicale versus conservatrice

OBJECTIVE

To compare the impact of conservative and radical strategies for placenta accreta on maternal morbidity and mortality.

METHODS

We retrospectively reviewed the medical records of all patients diagnosed with placenta accreta admitted to our tertiary center from January 1993 through October 2005. Two consecutive periods, A and B, were compared: during period A (january 1993 to June 1997), our written protocol called for the systematic manual removal of the placenta, to leave the uterine cavity empty. In period B (July 1997 to October 2005), we changed our policy and attempted to treat patients with a placenta accreta conservatively. The following outcomes over the two periods were compared: need for blood product transfusion, hysterectomy, intensive care admission, duration of stay in intensive care unit, sepsis and disseminated intravascular coagulation.

RESULTS

Fifty-one cases of placenta accreta were observed among 40281 deliveries (1.3/1000). Period B saw a reduction in the hysterectomy rate (11/13 versus 10/38; P < 0.01), the mean red blood cells transfused (3230+/-2170 versus 1081+/-1370 ml; P < 0.01) and disseminated intravascular coagulation (5/13 versus 1/38; P < 0.01) compared with period A. Seven cases of maternal infection were recorded during period B and none during period A (p = 0.22).

CONCLUSION

Conservative management of placenta accreta appears to be a safe alternative to radical management.

Antihypertensive effects of selective prostaglandin E2 receptor subtype 1 targeting

Clinical use of prostaglandin synthase-inhibiting NSAIDs is associated with the development of hypertension; however, the cardiovascular effects of antagonists for individual prostaglandin receptors remain uncharacterized. The present studies were aimed at elucidating the role of prostaglandin E2 (PGE2) E-prostanoid receptor subtype 1 (EP1) in regulating blood pressure. Oral administration of the EP1 receptor antagonist SC51322 reduced blood pressure in spontaneously hypertensive rats. To define whether this antihypertensive effect was caused by EP1 receptor inhibition, an EP1-null mouse was generated using a "hit-and-run" strategy that disrupted the gene encoding EP1 but spared expression of protein kinase N (PKN) encoded at the EP1 locus on the antiparallel DNA strand. Selective genetic disruption of the EP1 receptor blunted the acute pressor response to Ang II and reduced chronic Ang II-driven hypertension. SC51322 blunted the constricting effect of Ang II on in vitro-perfused preglomerular renal arterioles and mesenteric arteriolar rings. Similarly, the pressor response to EP1-selective agonists sulprostone and 17-phenyltrinor PGE2 were blunted by SC51322 and in EP1-null mice. These data support the possibility of targeting the EP1 receptor for antihypertensive therapy.

Bimatoprost, prostamide activity, and conventional drainage

PURPOSE

Despite structural similarity with prostaglandin F(2 alpha), the ocular hypotensive agent bimatoprost (Lumigan; Allergan, Inc., Irvine, CA) shows unique pharmacology in vitro and functional activity in vivo. Unfortunately, the precise mechanisms that underlie bimatoprost's distinctive impact on aqueous humor dynamics are unclear. The purpose of the present study was to investigate the effects of bimatoprost and a novel prostamide-selective antagonist AGN 211334 on human conventional drainage.

METHODS

Two model systems were used to test the consequences of bimatoprost and/or AGN 211334 treatment on conventional drainage. Human anterior segments in organ culture were perfused at a constant flow rate of 2.5 microL/min while pressure was recorded continuously. After stable baseline facilities were established, segments were treated with drug(s), and pressure was monitored for an additional 3 days. In parallel, the drugs' effects on hydraulic conductivity of human trabecular meshwork (TM) cell monolayers were evaluated. Pharmacological properties of AGN 211334 were characterized in isolated feline iris preparations in organ culture and heterologously expressed G-protein-coupled receptors were examined in vitro.

RESULTS

Bimatoprost increased outflow facility by an average of 40% +/- 10% within 48 hours of treatment (n = 10, P < 0.001). Preincubation or coincubation with AGN 211334 significantly blunted bimatoprost's effects by 95% or 43%, respectively. Similar results were obtained in cell culture experiments in which bimatoprost increased hydraulic conductivity of TM cell monolayers by 78% +/- 25%. Pretreatment with AGN 211334 completely blocked bimatoprost's effects, while coincubation decreased its effects on average by 74%. In both models, AGN 211334 alone significantly decreased fluid flux across trabecular tissues and cells.

CONCLUSIONS

The findings indicate that bimatoprost interacts with a prostamide receptor in the trabecular meshwork to increase outflow facility.

Stimulation of prostanoid IP and EP2 receptors dilates retinal arterioles and increases retinal and choroidal blood flow in rats

We examined the effects of vasodilatory prostaglandins (prostacyclin and prostaglandin E(2)) and selective agonists for prostanoid EP(2) and EP(4) receptor on the diameters of retinal blood vessels and fundus (retinal/choroidal) blood flow in rats. Male Wistar rats (8- to 10-week-old) were treated with tetrodotoxin (50 microg/kg, i.v.) to eliminate any nerve activity and prevent movement of the eye and infused with a mixture solution of norepinephrine and epinephrine (1:9) to maintain adequate systemic circulation under artificial ventilation. Fundus images were captured with a digital camera that was equipped with the special objective lens for small animals, and the diameters of retinal arterioles and venules were measured on a personal computer. Fundus blood flow was estimated using a laser Doppler flowmetry. Intravenous infusions of prostacyclin and prostaglandin E(2) dilated retinal blood vessels, increased fundus blood flow and decreased systemic blood pressure in a dose-dependent manner. The effects of vasodilatory prostaglandins on retinal arterioles were greater than those on retinal venules. Similarly, a prostanoid EP(2) receptor agonist (ONO-AE1-259-01) dilated retinal blood vessels, and increased fundus blood flow and decreased systemic blood pressure. However, a prostanoid EP(4) receptor agonist (ONO-AE1-329) failed to increase fundus blood flow, despite its comparable depressor response with those to vasodilatory prostaglandins and the prostanoid EP(2) receptor agonist. The responses to forskolin, an activator of adenylyl cyclase, were very similar to those to prostacyclin and the prostanoid EP(2) receptor agonist. These results suggest that prostacyclin and prostaglandin E(2) act as vasodilators in retinal and choroidal circulation, and prostanoid IP and EP(2) receptors play an important role in the regulation of ocular hemodynamics in rats.

Prostamides (prostaglandin-ethanolamides) and their pharmacology

The prostamides are part of a large and continually expanding series of pharmacologically unique neutral lipids. They are COX-2 derived oxidation products of the endocannabinoid/endovanniloid anandamide. Prostamide pharmacology is unique and, as in the case of the endocannabinoids anandamide and 2-arachidonylglycerol, bears little resemblance to that of the corresponding free acids. By virtue of its close relationship to the anti-glaucoma drug bimatoprost, prostamide F(2alpha) has received the greatest research attention. Prostamide F(2alpha) and bimatoprost effects appear independent of prostanoid FP receptor activation, according to a litany of agonist studies. Studies involving freshly isolated and separate feline iridial smooth muscle cells revealed that bimatoprost and FP receptor agonists stimulated different cells, without exception. This suggests the existence of receptors that preferentially recognize prostamide F(2alpha). The recent discovery of prostamide antagonists has provided further support for prostamide receptors as discrete entities. The prototypical prostamide antagonists, AGN 204396 and 7, blocked the effects of prostamide F(2alpha) and bimatoprost but not those of PGF(2alpha) and FP receptor agonists in the feline iris. Second generation more potent prostamide antagonists, such as AGN 211334, should allow the role of prostamides in health and disease to be elucidated. From the therapeutics standpoint, the prostamide F(2alpha) analogue bimatoprost is the most efficacious ocular hypotensive agent currently available for the treatment of glaucoma.

Transient allodynia pain models in mice for early assessment of analgesic activity

BACKGROUND AND PURPOSE

The most common preclinical models of neuropathic pain involve surgical ligation of sensory nerves, which is especially difficult in mice. Transient models of chemically sensitized allodynia are potentially useful for rapidly characterizing the analgesic profile of compounds and conducting mechanistic studies.

EXPERIMENTAL APPROACH

Increasing doses of NMDA, sulprostone (an EP1/EP3 prostaglandin receptor agonist) or phenylephrine (an alpha (1) adrenoceptor agonist) were injected intrathecally (i.t.) or i.p., and animals were subsequently assessed for allodynia. The effects of receptor antagonists and analgesic compounds on allodynia were also assessed.

KEY RESULTS

A comparison of total body doses that cause allodynia following spinal or systemic administration indicated that NMDA induces allodynia in the spinal cord while sulprostone and phenylephrine act through a peripheral mechanism. Inhibition of the allodynia with receptor antagonists indicated that each agent induces allodynia by a distinct mechanism. The three models were benchmarked using compounds known to be active in neuropathic pain patients and nerve injury animal models, including gabapentin, amitriptyline and clonidine.

CONCLUSIONS AND IMPLICATIONS

These transient allodynia models are a useful addition to the toolbox of preclinical pain models. They are simple, rapid and reproducible, and will be especially useful for characterizing the pain phenotype of knockout mice.

Hydrolysis of Prostaglandin Glycerol Esters by the Endocannabinoid-Hydrolyzing Enzymes, Monoacylglycerol Lipase and Fatty Acid Amide Hydrolase

Cyclooxygenase-2 (COX-2) can oxygenate the endocannabinoids, arachidonyl ethanolamide (AEA) and 2-arachidonylglycerol (2-AG), to prostaglandin-H2-ethanolamide (PGH2-EA) and -glycerol ester (PGH2-G), respectively. Further metabolism of PGH2-EA and PGH2-G by prostaglandin synthases produces a variety of prostaglandin-EA's and prostaglandin-G's nearly as diverse as those derived from arachidonic acid. Thus, COX-2 may regulate endocannabinoid levels in neurons during retrograde signaling or produce novel endocannabinoid metabolites for receptor activation. Endocannabinoid-metabolizing enzymes are important regulators of their action, so we tested whether PG-G levels may be regulated by monoacylglycerol lipase (MGL) and fatty acid amide hydrolase (FAAH). We found that PG-Gs are poor substrates for purified MGL and FAAH compared to 2-AG and/or AEA. Determination of substrate specificity demonstrates a 30-100- and 150-200-fold preference of MGL and FAAH for 2-AG over PG-Gs, respectively. The substrate specificity of AEA compared to those of PG-Gs was approximately 200-300 fold higher for FAAH. Thus, PG-Gs are poor substrates for the major endocannabinoid-degrading enzymes, MGL and FAAH.

Prostaglandin E2 (PGE2) inhibits glutamatergic synaptic transmission in dorsolateral periaqueductal gray (dl-PAG)

The purpose of this study was to determine the role of prostaglandin E(2) (PGE(2)) in modulating neuronal activity of the dorsolateral periaqueductal gray (dl-PAG) through excitatory and inhibitory synaptic inputs. First, whole cell voltage-clamp recording was performed to obtain excitatory and inhibitory postsynaptic currents (EPSCs and IPSCs) of the dl-PAG neurons. Our results show that PGE(2) significantly decreased the frequency of miniature EPSCs and amplitude of evoked EPSCs. The effects were mimicked by sulprostone, an agonist to PGE(2) EP(3) receptors. In contrast, PGE(2) had no distinct effect on IPSCs. In addition, spontaneous action potential of the dl-PAG neurons was recorded using whole cell current-clamp methods. PGE(2) significantly attenuated the discharge rate of the dl-PAG neurons. The decreased firing activity was abolished in the presence of glutamate NMDA and non-NMDA receptor antagonists. The results from the current study provide the first evidence indicating that PGE(2) inhibits the neuronal activity of the dl-PAG via selective attenuation of glutamatergic synaptic inputs, likely due to the activation of presynaptic EP(3) receptors.

COX-2 oxidative metabolite of endocannabinoid 2-AG enhances excitatory glutamatergic synaptic transmission and induces neurotoxicity

Neuroinflammation has been implicated in the pathogenesis of neurodegenerative diseases. Cyclooxygenase-2 (COX-2), an inducible enzyme converting arachidonic acid (AA) to prostaglandins, is the key player in neuroinflammation. It has been long thought that the COX-2-mediated neuronal injury/degeneration is attributed to the increased production of AA-derived prostaglandins. Recent studies show that endogenous cannabinoid 2-arachidonoylglycerol (2-AG) is a natural substrate for COX-2, and it can be oxygenated by COX-2 to form prostaglandin glyceryl esters. In this study, we demonstrate that prostaglandin E(2) glyceryl ester (PGE(2)-G), a major COX-2 oxidative metabolite of 2-arachidonoylglycerol, enhanced hippocampal glutamatergic synaptic transmission indicated by the increased frequency of miniature excitatory post-synaptic currents, and induced neuronal injury/death revealed by the terminal transferase dUTP nick end labeling staining and caspase 3 activation. The actions of PGE(2)-G are not mediated via a cannabinoid receptor 1, but mediated through ERK, p38 mitogen-activated protein kinase, IP(3), and NF-kappaB signal transduction pathways. In addition, the PGE(2)-G-induced neurotoxicity is attenuated by blockade of the NMDA receptors. Our results suggest that the COX-2 oxidative metabolism of endocannabinoids is an important mechanism contributing to the inflammation-induced neurodegeneration.

Discovery of novel prostaglandin analogs of PGE2 as potent and selective EP2 and EP4 receptor agonists

Analogs of PGE(2) with introduction of diene groups at the omega-side chain have been synthesized and evaluated for their binding affinity for EP(2) and EP(4) receptors. An optimized analog (compound 9b) showed high potency and selectivity for the EP(4) receptor over other known receptors.

[Place of the sulprostone in therapeutic interruptions of the pregnancy]

BACKGROUND

Therapeutic interruption of the pregnancies of the 2nd and 3-rd quarter is often badly accepted by the patients and it is original that his realization is easy, effective and the less traumatic possible. In this indication, the sulprostone (Nalador) is a big contribution.

AIM

The purpose of our study is to review this product, to describe our experience concerning its use in the therapeutic interruptions of pregnancies and to study alternatives in case of failure or of against indication in its use.

METHODS

It is about a forward-looking study opened from the 01-07-02 led in the service "A" of the CMNT. We brought together 30 women where a therapeutic interruption of the pregnancy was put and who did'nt present of against indications to the sulprostone.

RESULTS

The average age was of 27 years with extremes from 18 to 39 years 50% of our patients were nullipares. The terms of pregnancy varied from 16 to 28 LIMITED COMPANIES with an average of 20 LIMITED COMPANIES. The indications of these terminations of pregnancy were maternal in 33.33% of cases and foetal in 66.66% of cases. The average number of light bulbs of Nalador used by the women was of 2.25 with extremes going from 1 to 4. The delay of eviction from the beginning of the induction was on average of 21 hours, with a rate of success of 90%. We did not regret any break uterine Delivery was incomplete requiring a uterine revision under general anesthetic in 5 cases. Tolerance was good in general In case of failure alternatives were: the misoprostol (cytotec *), the Probe extra amniotic dries and the wet Probe.

CONCLUSION

The sulprostone by intravenous way constitutes an effective method of medical interruption of the pregnancy in the 2-nd and 3-rd quarter with a satisfactory tolerance and a rate of success of 90 %.