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Octocoral of the genus Clavularia is a kind of marine invertebrate possessing abundant cytotoxic secondary metabolites, such as prostanoids and dolabellanes. In our continuous natural product study of C. spp., two previously undescribed prostanoids [clavulone I-15-one ( 1 ) and 12- O -deacetylclavulone I ( 2 )] and eleven known analogs ( 3 - 13 ) were identified. The structures of these new compounds were elucidated based on analysis of their 1D and 2D NMR, HRESIMS, and IR data. Additionally, all tested prostanoids ( 1 and 3 - 13 ) showed potent cytotoxic activities against the human oral cancer cell line (Ca9-22). The major compound 3 showed cytotoxic activity against the Ca9-22 cells with the IC 50 value of 2.11 ± 0.03 μg/mL, which echoes the cytotoxic effect of the coral extract. In addition, in silico tools were used to predict the possible effects of isolated compounds on human tumor cell lines and nitric oxide production, as well as the pharmacological potentials.

Purpose: The retina contains a number of vasoactive neuropeptides and corresponding receptors, but the role of these neuropeptides for tone regulation of retinal arterioles has not been studied in detail., Methods: Porcine arterioles with preserved perivascular retinal tissue were mounted in a wire myograph, and the tone was measured after the addition of increasing concentrations of bradykinin, vasoactive intestinal peptide (VIP), neuropeptide Y (NPY), substance P (SP), calcitonin gene-related peptide (CGRP) and brain natriuretic peptide (BNP). The experiments were performed during inhibition of the synthesis of nitric oxide (NO), prostaglandins and dopamine and were repeated after removal of the perivascular retinal tissue., Results: Bradykinin, VIP and CGRP induced significant concentration-dependent dilatation and NPY significant concentration-dependent contraction of the arterioles in the presence of perivascular retinal tissue (p < 0.03 for all comparisons) but not on isolated arterioles. BNP and SP had no effect on vascular tone. The NOS inhibitor L-NAME reduced bradykinin- and VIP-induced relaxation (p < 0.001 for both comparisons), whereas none of the other inhibitors influenced the vasoactive effects of the studied neuropeptides., Conclusion: The effects of neuropeptides on the tone of retinal arterioles depend on the perivascular retinal tissue and may involve effects other than those mediated by nitric oxide, prostaglandins and adrenergic compounds. Investigation of the mechanisms underlying the vasoactive effect of neuropeptides may be important for understanding and treating retinal diseases where disturbances in retinal flow regulation are involved in the disease pathogenesis., (© 2023 The Authors. Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation.)

Signaling through prostaglandin E 2 EP3 receptor (EP3) actively contributes to the β-cell dysfunction of type 2 diabetes (T2D). In T2D models, full-body EP3 knockout mice have a significantly worse metabolic phenotype than wild-type controls due to hyperphagia and severe insulin resistance resulting from loss of EP3 in extra-pancreatic tissues, masking any potential beneficial effects of EP3 loss in the β cell. We hypothesized β-cell-specific EP3 knockout (EP3 βKO) mice would be protected from high-fat diet (HFD)-induced glucose intolerance, phenocopying mice lacking the EP3 effector, Gα z , which is much more limited in its tissue distribution. When fed a HFD for 16 wk, though, EP3 βKO mice were partially, but not fully, protected from glucose intolerance. In addition, exendin-4, an analog of the incretin hormone, glucagon-like peptide 1, more strongly potentiated glucose-stimulated insulin secretion in islets from both control diet- and HFD-fed EP3 βKO mice as compared with wild-type controls, with no effect of β-cell-specific EP3 loss on islet insulin content or markers of replication and survival. However, after 26 wk of diet feeding, islets from both control diet- and HFD-fed EP3 βKO mice secreted significantly less insulin as a percent of content in response to stimulatory glucose, with or without exendin-4, with elevated total insulin content unrelated to markers of β-cell replication and survival, revealing severe β-cell dysfunction. Our results suggest that EP3 serves a critical role in temporally regulating β-cell function along the progression to T2D and that there exist Gα z -independent mechanisms behind its effects. NEW & NOTEWORTHY The EP3 receptor is a strong inhibitor of β-cell function and replication, suggesting it as a potential therapeutic target for the disease. Yet, EP3 has protective roles in extrapancreatic tissues. To address this, we designed β-cell-specific EP3 knockout mice and subjected them to high-fat diet feeding to induce glucose intolerance. The negative metabolic phenotype of full-body knockout mice was ablated, and EP3 loss improved glucose tolerance, with converse effects on islet insulin secretion and content.

Cancer treatment is challenged due to immunosuppressive inflammatory tumour microenvironment (TME) caused by infiltration of tumour-promoting and inhibition of tumour-inhibiting immune cells. Here, we report the engineering of chimeric nanomicelles (NMs) targeting the cell proliferation using docetaxel (DTX) and inflammation using dexamethasone (DEX) that alters the immunosuppressive TME. We show that a combination of phospholipid-DTX conjugate and PEGylated-lipid-DEX conjugate can self-assemble to form sub-100 nm chimeric NMs (DTX-DEX NMs). Anti-cancer activities against syngeneic and xenograft mouse models showed that the DTX-DEX NMs are more effective in tumour regression, enhance the survival of mice over other treatment modes, and alter the tumour stroma. DTX-DEX NMs cause a significant reduction in myeloid-derived suppressor cells, alter the polarization of macrophages, and enhance the accumulation of cytotoxic CD4 + and CD8 + T cells in tumour tissues, along with alterations in cytokine expression. We further demonstrated that these DTX-DEX NMs inhibit the synthesis of prostaglandins, especially PGE2, by targeting the cyclooxygenase 2 that is partly responsible for immunosuppressive TME. Therefore, this study presents, for the first time, the engineering of lithocholic acid-derived chimeric NMs that affect the prostaglandin pathway, alter the TME, and mitigate tumour progression with enhanced mice survival., Competing Interests: Declaration of competing interest The authors declare no conflict of interest in this work., (Copyright © 2023. Published by Elsevier B.V.)

Introduction: Intestinal manipulation (IM)-induced inflammation could contribute to postoperative ileus (POI) pathophysiology via the modulation of prostanoid pathways. To identify the prostanoids involved, we aimed to characterize the profile of prostanoids and their synthesis enzyme expression in a murine model of POI and to determine whether the altered prostanoids could contribute to POI., Methods: Four or 14 h after IM in mice, gastrointestinal (GI) motility and intestinal epithelial barrier (IEB) permeability were assessed in vivo and ex vivo in Ussing chambers. Using high sensitivity liquid chromatography-tandem mass spectrometry, we characterized the tissue profile of polyunsaturated fatty acid metabolites in our experimental model. Finally, we evaluated in vivo the effects of the prostanoids studied upon IM-induced gut dysfunctions., Results: We first showed that 14 h after IM was significantly faster than jejunal transit at 4 h post-IM, although it remained significantly increased compared to the control. In contrast, we showed that IM-induced inflammation increase in jejunum permeability was similar after four and 14 h. We next showed that expression of prostacyclin synthase and hemopoietic prostaglandin-D synthase mRNA and their products were significantly reduced 14 h after IM as compared to controls. Furthermore, 15-deoxy-delta 12,14-Prostaglandin J2 reduced the IM-induced inflammation increase in IEB permeability but had no effect on GI motility. In contrast, PGI 2 increased IM-induced IEB permeability and motility dysfunctions., Conclusions: Arachidonic acid derivative contributes differentially to GI dysfunction in POI. The decrease of 15-deoxy-delta 12,14-Prostaglandin J2 levels induced by IM could contribute to impaired GI dysfunctions in POI and could be considered as putative therapeutic targets to restore barrier dysfunctions associated with POI., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: The recreational drug ±3,4-methylenedioxymethamphetamine (MDMA; also known as "ecstasy") has unusual subjective prosocial and empathogenic effects, and has exhibited potential as an adjunct to psychotherapy in recent years. However, there has been some concern regarding possible neuropsychiatric symptoms, such as cognitive impairment and dependence, emerging after abstinence. Therefore, this study aimed to evaluate the mechanism underlying cognitive impairment during MDMA withdrawal. To achieve this, we focused on the arachidonic acid cascade, which is related to addiction to some abusive drugs., Methods: A novel object recognition task was used to investigate cognitive function in mice. Furthermore, we quantified prostaglandin E 2 during MDMA withdrawal., Results: The recognition index significantly decreased during withdrawal after repeated administration of MDMA (10mg/kg, i.p., once daily for 7 days), but not following co-administration of diclofenac (10mg/kg, i.p.), a cyclooxygenase inhibitor. On day 1, following repeated MDMA treatment, prostaglandin E 2 content significantly increased in the hippocampus but not in the prefrontal cortex and striatum., Conclusions: Our findings indicate that activation of the arachidonic acid cascade at least in the hippocampus is likely involved in the development of recognition memory impairment during MDMA withdrawal. Therefore, co-use of cyclooxygenase inhibitors with MDMA may reduce concerns regarding MDMA-induced impairment of recognition memory., Competing Interests: Declaration of Competing Interest On behalf of all authors, the corresponding author states that there are no conflicts of interest., (Copyright © 2024. Published by Elsevier B.V.)

Lung adenocarcinoma (LUADC) belongs to the most prevalent and lethal cancer types. As 15-deoxy-Δ12,14-prostaglandin J 2 (15d-PGJ 2 ) displays anti-oxidative, -inflammatory, and -cancer properties, we investigated whether this cyclopentenone PG, a stable degradation end-product of cyclooxygenase-generated PGD 2 , exerts beneficial effects in three LUADC cell lines (A549, H1299, H23). We here report that 15d-PGJ 2 had substantial cytotoxic effects in all three LUADC cell lines by promoting early apoptosis and inhibiting the cell cycle, proliferation, and migration. As indicators of cell malignancy, scratch closure and colony formation were significantly inhibited by 15d-PGJ 2 . 15d-PGJ 2 induced generation of ROS and subsequent activation of MAPKs. Expression of Nrf-2, a well-known tumor driver, was markedly diminished by 15d-PGJ 2 treatment. Although PPARγ, DP1, and DP2 are expressed in LUADC cells, blocking these receptors with specific inhibitors (SR16832 and BW245C) did not reverse 15d-PGJ 2 -mediated cytotoxicity, suggesting receptor-independent effects. 15d-PGJ 2 decreased SIRT1 expression in LUADC cells and the knockdown of SIRT1 diminished the cytotoxic effects of 15d-PGJ 2 . Importantly, 15d-PGJ 2 significantly reduced tumor growth using the chorioallantoic membrane (CAM) assay. The structural analog of 15d- PGJ 2 , 9,10-dihydro-15d-PGJ 2 (lacking the α,β-unsaturated ketone structural element), did not show any toxic effects in LUADC cells. Altogether, our findings suggest that 15d-PGJ 2 led to significantly reduced tumor growth and cell proliferation in three LUADC cell lines. The CAM assay results suggest that 15d-PGJ 2 is a suitable endogenous compound to interfere with LUADC tumor progression. We show that SIRT1 modulates the effects of 15d-PGJ 2 and may be used as a therapeutic target for LUADC., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Acute heat exposure increases skeletal muscle blood flow in humans. However, the mechanisms mediating this hyperemic response remain unknown. The cyclooxygenase pathway is active in skeletal muscle, is heat sensitive, and contributes to cutaneous thermal hyperemia in young healthy humans. Therefore, the purpose of this study was to test the hypothesis that cyclooxygenase inhibition would attenuate blood flow in the vastus lateralis muscle during localized heating. Twelve participants (6 women) were studied on two separate occasions: 1 ) time control (i.e., no ibuprofen); and 2 ) ingestion of 800 mg ibuprofen, a nonselective cyclooxygenase inhibitor. Experiments were randomized, counter-balanced, and separated by at least 10 days. Pulsed short-wave diathermy was used to induce unilateral deep heating of the vastus lateralis for 90 min, whereas the contralateral leg served as a thermoneutral control. Microdialysis was utilized to bypass the cutaneous circulation and directly measure local blood flow in the vastus lateralis muscle of each leg via the ethanol washout technique. Heat exposure increased muscle temperature and local blood flow (both P < 0.01 vs. baseline). However, the thermal hyperemic response did not differ between control and ibuprofen conditions ( P ≥ 0.2). Muscle temperature slightly decreased for the thermoneutral leg ( P < 0.01 vs. baseline), yet local blood flow remained relatively unchanged across time for control and ibuprofen conditions (both P ≥ 0.7). Taken together, our data suggest that inhibition of cyclooxygenase-derived vasodilator prostanoids does not blunt thermal hyperemia in skeletal muscle of young healthy humans. NEW & NOTEWORTHY Acute heat exposure increases skeletal muscle blood flow in humans. However, the mechanisms mediating this hyperemic response remain unknown. Using a pharmacological approach combined with microdialysis, we found that thermal hyperemia in the vastus lateralis muscle was well maintained despite the successful inhibition of cyclooxygenase. Our results suggest that cyclooxygenase-derived vasodilator prostanoids do not contribute to thermal hyperemia in skeletal muscle of young healthy humans.

Conventional induction protocol (CIP) of calving in buffaloes employs the intramuscular (IM) administration of dexamethasone (40 mg) and cloprostenol sodium (500 μg). If there is no progression in terms of cervical dilatation, then a second dose of cloprostenol sodium (500 μg) is administered intramuscularly. This protocol possesses certain demerits: (1) a wide range of response time intervals, and (2) increased risk of fetal membrane retention. Considering the cervix as a caudal continuation of the myometrium with its own contractile potential, and the limitations of CIP, we developed intracervical (IC) drug administration route in buffaloes. The proposed technique was evaluated for its use in a total of 22 cases of incomplete cervical dilatation in uterine torsion-affected buffaloes (IC-14 and IM-8). In addition to CIP, the IC group received an intracervical injection of cloprostenol sodium (500 μg) at the start of the experiment whereas the IM group received an extra intramuscular dose of cloprostenol sodium (500 μg) either after 24 h or when no progression in cervical dilatation is noticed. Surprisingly, the average response time during the experiment in the IC group was 5.8 h shorter (p < 0.000) than in the IM group (IC-5.7 ± 0.17 h vs. IM-11.9 ± 0.74 h). The duration from calving to fetal membrane expulsion (IC-12.8 ± 0.60 h vs. IM-17.5 ± 1.40 h; p < 0.002) and incidence of retention of fetal membrane were also less in the IC group (57.1% vs. 87.5%). The proposed intracervical drug administration potentiates cervical dilatation and can be regarded as a safe, effective, and feasible technique for attaining reliable results., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Purpose: Acute rejection is a frequent complication among lung transplant recipients and poses substantial therapeutic challenges. 15-hydroxyprostaglandin dehydrogenase (15-PGDH), an enzyme responsible for the inactivation of prostaglandin E2 (PGE2), has recently been implicated in inflammatory lung diseases. However, the role of 15-PGDH in lung transplantation rejection remains elusive. The present study was undertaken to examine the expression of 15-PGDH in rejected lung allografts and whether inhibition of 15-PGDH ameliorates acute lung allograft rejection., Methods: Orthotopic mouse lung transplantations were performed between donor and recipient mice of the same strain or allogeneic mismatched pairs. The expression of 15-PGDH in mouse lung grafts was measured. The efficacy of a selective 15-PGDH inhibitor (SW033291) in ameliorating acute rejection was assessed through histopathological examination, micro-CT imaging, and pulmonary function tests. Additionally, the mechanism underlying the effects of SW033291 treatment was explored using CD8 + T cells isolated from mouse lung allografts., Results: Increased 15-PGDH expression was observed in rejected allografts and allogeneic CD8 + T cells. Treatment with SW033291 led to an accumulation of PGE2, modulation of CD8 + T-cell responses and mitochondrial activity, and improved allograft function and survival., Conclusion: Our study provides new insights into the role of 15-PGDH in acute lung rejection and highlights the therapeutic potential of inhibiting 15-PGDH for enhancing graft survival. The accumulation of PGE2 and modulation of CD8 + T-cell responses represent potential mechanisms underlying the benefits of 15-PGDH inhibition in this model. Our findings provide impetus for further exploring 15-PGDH as a target for improving lung transplantation outcomes., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Two new prostaglandin-like compounds callicarboric acids A-B (1-2), along with six known compounds (3-8) were isolated from the stems of Callicarpa arborea Roxb. Their structures were determined with the help of modern spectroscopic techniques such as NMR, UV, IR, HR-ESI-MS, ECD, and ORD with the assistance of quantum chemical calculations. Compound 1 exhibited remarkable anti-NLRP3 inflammasome activation potential, demonstrating an IC 50 value of 0.74 μM. Additionally, by reducing GSDMD-NT production, inhibiting caspase-1 activation, and suppressing IL-1β secretion, it effectively mitigated NLRP3 inflammasome-induced pyroptosis in J774A.1 cells. These findings indicate that compound 1 possesses the capability to be a valuable candidate for further research and development as an NLRP3 inflammasome inhibitor., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

Recent studies have demonstrated that visfatin participates in the regulation of female reproduction. Due to the lack of data concerning the level of visfatin in the ovarian follicles of pigs, one of the most economically important livestock species, the aim of this study was to investigate the expression and localisation of visfatin and the follicular fluid concentration in the ovarian follicles of prepubertal and mature gilts. We also aimed to examine the in vitro effects of gonadotropins (LH, FSH), insulin, progesterone (P 4 ), oestradiol (E 2 ), prostaglandin E 2 (PGE 2 ) and F 2α (PGF 2α ) on visfatin levels. In the present study, we have demonstrated that visfatin expression is dependent on the maturity of the animals and the stage of ovarian follicle development. Visfatin signal was detected in individual follicular compartments from primordial to antral follicles and even in atretic follicles. We have shown that the expression of visfatin in granulosa cells was higher than in theca cells. The level of visfatin is upregulated by LH, FSH, E 2, and P 4 and downregulated by insulin, while prostaglandins have modulatory effects, dependent on the dose and type of ovarian follicular cells. To summarise, our research has shown that visfatin is widely expressed in the ovarian follicles of prepubertal and mature pigs, and its expression is regulated by gonadotropins, insulin, steroids, and prostaglandins, suggesting that visfatin appears to be an important intra-ovarian factor that could regulate porcine ovarian follicular function., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The metabolic pathways leading from hypoxia to retinal vasodilatation can involve effects of both purines and prostaglandins, but the effects of these compounds at different vascular branching levels are unknown. The purpose of the present study was to investigate differential effects of purines and prostaglandins in hypoxia-induced dilatation of retinal arterioles, precapillary arterioles and capillaries ex vivo. Porcine hemiretinas were mounted in a tissue chamber while monitoring temperature, pH, and oxygen tension. The effect of hypoxia on the diameter of larger arterioles, precapillary arterioles and capillaries was studied in the presence of the ecto-nucleotidase inhibitor AOPCP, the nonselective P2 purinoreceptor antagonist PPADS, the A2B adenosine receptor antagonist MRS 1754, the A3 adenosine receptor antagonist MRS 1523, the EP1 receptor antagonist SC-19220, the EP2 receptor antagonist PF-04418948, the EP3 receptor antagonist L-798,106, the EP4 receptor antagonist L-161-982, the prostaglandin synthesis inhibitor ibuprofen, and ibuprofen combined with AOPCP or ATP. Hypoxia-induced dilatation in arterioles was reduced by the A2B adenosine receptor antagonist (p < 0.01) and increased by the EP2 and the EP3 receptor antagonists (p < 0.01 for both comparisons). In precapillary arterioles the dilatation was reduced by the EP2 receptor antagonist (p < 0.04) and increased by the EP1 receptor antagonist (p < 0.03), whereas in capillaries the dilatation was increased by both the A3 adenosine receptor antagonist (p < 0.01), by ibuprofen in combination with the unspecific ecto-nucleotidase inhibitor AOPCP (p = 0.04) and by the prostaglandin EP3 receptor antagonist. Hypoxia-induced dilatation of retinal vessels is influenced by adenosine A2B and A3 receptors, and by the prostaglandin EP1, EP2 and EP3 receptors. The effects mediated by these receptors differ at different branching levels of the resistance vessels., Competing Interests: Declaration of competing interest Charlotte Ernst: None, Toke Bek: None., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Approximately 17.3% of the global population exhibits an element of zinc (Zn 2+ ) deficiency. One symptom of Zn 2+ deficiency is increased bleeding through impaired hemostasis. Platelets are crucial to hemostasis and are inhibited by endothelial-derived prostacyclin (prostaglandin I 2 [PGI 2 ]), which signals via adenylyl cyclase (AC) and cyclic adenosine monophosphate signaling. In other cell types, Zn 2+ modulates cyclic adenosine monophosphate concentrations by changing AC and/or phosphodiesterase activity., Objectives: To investigate if Zn 2+ can modulate platelet PGI 2 signaling., Methods: Platelet aggregation, spreading, and western blotting assays with Zn 2+ chelators and cyclic nucleotide elevating agents were performed in washed platelets and platelet-rich plasma conditions. In vitro thrombus formation with various Zn 2+ chelators and PGI 2 was assessed in whole blood., Results: Incubation of whole blood or washed platelets with Zn 2+ chelators caused either embolization of preformed thrombi or reversal of platelet spreading, respectively. To understand this effect, we analyzed resting platelets and identified that incubation with Zn 2+ chelators elevated pVASP ser157 , a marker of PGI 2 signaling. In agreement that Zn 2+ affects PGI 2 signaling, addition of the AC inhibitor SQ22536 blocked Zn 2+ chelation-induced platelet spreading reversal, while addition of Zn 2+ blocked PGI 2 -mediated platelet reversal. Moreover, Zn 2+ specifically blocked forskolin-mediated AC reversal of platelet spreading. Finally, PGI 2 inhibition of platelet aggregation and in vitro thrombus formation was potentiated in the presence of low doses of Zn 2+ chelators, increasing its effectiveness in inducing platelet inhibition., Conclusion: Zn 2+ chelation potentiates platelet PGI 2 signaling, elevating PGI 2 's ability to prevent effective platelet activation, aggregation, and thrombus formation., Competing Interests: Declaration of competing interests There are no competing interests to disclose., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Approximately 1 in 4 pregnant women undergo induction of labor. Meta-analyses have shown that mechanical methods of induction of labor are safe and effective, as is starting induction in an outpatient setting. However, few studies have evaluated outpatient balloon catheter induction in comparison with pharmacologic methods., Objective: This study aimed to determine whether women who underwent outpatient induction of labor with a balloon catheter would have a lower cesarean delivery rate than women who underwent inpatient induction of labor with vaginal prostaglandin E2 without an increase in adverse maternal or neonatal events., Study Design: This was a superiority randomized controlled trial. The eligibility criteria were pregnant women (nullipara and multipara) with a live singleton fetus in vertex presentation with any medical comorbidity who underwent planned induction of labor at term and who had an initial modified Bishop Score of 0 to 6 at 1 of 11 public maternity hospitals in New Zealand. The intervention groups were outpatient single balloon catheter induction in comparison with inpatient vaginal prostaglandin E2 induction. The primary hypothesis was that participants who started their induction at home with a balloon catheter would have a lower risk for cesarean delivery than participants who started their induction with prostaglandins and remained in hospital throughout. The primary outcome was cesarean delivery rate. Participants were randomized using a centralized secure online randomization website in a 1:1 ratio, stratified by parity and hospital. The participants and outcome assessors were not blinded to group allocation. An intention-to-treat analysis with adjustment for stratification variables was used., Results: A total of 539 participants were randomized to outpatient balloon catheter induction, and 548 participants were randomized to inpatient prostaglandin induction; the mode of birth was reported for all participants. The cesarean delivery rate was 41.0% among participants allocated to outpatient balloon induction and 35.2% among those allocated to inpatient prostaglandin induction (adjusted odds ratio, 1.27; 95% confidence interval, 0.98-1.65). Women in the outpatient balloon catheter group were more likely to have artificial rupture of membranes and to received oxytocin and an epidural. No differences were found in the rates of adverse maternal or neonatal events., Conclusion: Outpatient balloon catheter induction was not found to reduce the cesarean delivery rate when compared with inpatient vaginal prostaglandin E2 induction. The use of balloon catheters in an outpatient setting does not seem to increase the rate of adverse events for mothers or babies and can be offered routinely., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Visceral pain is a prominent feature of various gastrointestinal diseases. The P2X7 receptor is expressed by multiple cell types including dorsal root ganglion satellite glial cells, macrophages, and spinal microglia, all of which have been implicated in nociceptive sensitization. We have used the selective and CNS penetrant P2X7 receptor antagonist Lu AF27139 to explore this receptor's role in distinct rat models of inflammatory and visceral hypersensitivity. Rats injected with CFA in the hindpaw displayed a marked reduction in hindpaw mechanical threshold, which was dose-dependently reversed by Lu AF27139 (3-30 mg/kg, p.o.). In rats injected with TNBS in the proximal colon, the colorectal distension threshold measured distally was significantly lower than sham treated rats at 7 days post-injection (P < 0.001), indicative of a marked central sensitization. Colonic hypersensitivity was also reversed by Lu AF27139 (10-100 mg/kg) and by the κ-opioid receptor agonist U-50,488H (3 mg/kg, s.c.). Moreover, both Lu AF27139 and U-50,488H prevented a TNBS-induced increase in spinal and brain levels of PGE2 and LTB4, as well as an increase in brain levels of PGF2α and TXB2. Lu AF27139 was well tolerated as revealed by a lack of significant effect on rotarod motor function and coordination at all doses tested up to 300 mg/kg. Thus, P2X7 receptor antagonism is efficacious in a rat model of visceral pain, via a mechanism which potentially involves attenuation of microglial function within spinal and/or supraspinal pain circuits, albeit a peripheral site of action cannot be excluded., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Schinus molle is a plant traditionally used in Mexico to treat gastric disorders. However, no scientific evidence has been reported on its gastroprotective effect. The aim of the current contribution was to conduct a bioassay-guided study on S. molle to evaluate its gastroprotective activity in a model of Wistar rats given ethanol orally to induce gastric lesions. The hexane and dichloromethane extracts from the tested plant showed over 99% gastroprotection at a dose of 100 mg/kg. From the hexane extract, two of the three fractions (F1 and F2) afforded over 99% gastroprotection. The F1 fraction was subjected to column chromatography, which revealed a white solid. Based on the ESI-MS analysis, the two main compounds in this solid were identified. The predominant compound was probably a triterpene. This mixture of compounds furnished about 67% gastroprotection at a dose of 100 mg/kg. Pretreatment with L-NAME, indomethacin, and NEM was carried out to explore the possible involvement of nitric oxide, prostaglandins, and/or sulfhydryl groups, respectively, in the gastroprotective activity of the white solid. We found evidence for the participation of all three factors. No antisecretory activity was detected (tested by pylorus ligation). In conclusion, evidence is herein provided for the first time of the gastroprotective effect of S. molle .

Blutaparon portulacoides is a Brazilian plant species that is widely used in folk medicine. The present study investigated the role of an aqueous extract of B. portulacoides against hypertension in spontaneously hypertensive rats. The aqueous extract of B. portulacoides was obtained from the whole plant. Its chemical profile was analyzed by ultraperformance liquid chromatography-tandem mass spectrometry. The acute toxicity of the aqueous extract of B. portulacoides was evaluated in female Wistar rats. Male 6-month-old spontaneously hypertensive rats then received the aqueous extract of B. portulacoides (30, 100, and 300 mg/kg), hydrochlorothiazide (25 mg/kg), or vehicle once daily for 28 days. On days 1, 14, and 28, the diuretic effects of the aqueous extract of B. portulacoides were evaluated. The role of prostaglandins and the nitric oxide-cyclic guanosine monophosphate-potassium channel pathway in the diuretic activity of the aqueous extract of B. portulacoides was also investigated. At the end of the treatment, hepatic and renal biochemical markers, serum nitrotyrosine, malondialdehyde, nitrite, and aldosterone levels, and angiotensin-converting enzyme activity were measured. The electrocardiographic profile, blood pressure, and renal vascular reactivity were also assessed. The heart, kidneys, and liver were collected to determine relative organ weight, histopathology, and cardiac morphometry. Caffeic acid, ferulic acid, and several flavonoids were identified in the aqueous extract of B. portulacoides . No signs of toxicity were observed. Prolonged treatment with the aqueous extract of B. portulacoides (300 mg/kg) induced significant diuretic activity by activating the nitric oxide-cyclic guanosine monophosphate-potassium channel pathway. These effects reduced blood pressure and oxidative stress and prevented renal vascular dysfunction and left ventricular hypertrophy that was induced by hypertension. Overall, the present data suggest that the aqueous extract of B. portulacoides has important diuretic and cardioprotective effects by activation of the nitric oxide-cyclic guanosine monophosphate-potassium channel pathway., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Intervertebral disc (IVD) degeneration is a spinal disorder that triggers an inflammatory response and subsequent development of spinal pseudoarthrosis. The aim of the present study is to elucidate the role of the extracellular signal-regulated kinase (ERK) pathway in inflammation-induced IVD cells. Inflammatory human nucleus pulposus (NP) cells (NPCs) were induced using tumor necrosis factor-α and the ERK pathway was blocked using a selective molecule-based inhibitor U0126. Gene expression of catabolic and anabolic markers, proinflammatory, and NPCs markers was investigated. The enzymatic activity of matrix metalloproteinases (MMP)2/MMP9 was determined by gelatin zymography and nitrite production was assessed by Griess reaction. The NPC metabolic activity and viability were assessed using resazurin sodium-salt and live/dead assays, and subsequently, the specificity of U0126 on ERK1/2 signaling was determined. The catabolic enzyme MMP3 (p = 0.0001) and proinflammatory cytokine interleukin 6 (p = 0.036) were downregulated by U0126 in NPCs under inflammatory conditions. A significant increase of the cytokeratin 19 (p = 0.0031) was observed, suggesting a partial and possible recovery of the NP phenotype. U0126 does not seem to have an effect on prostaglandin production, aggrecanases, or other anabolic genes. We confirmed that U0126 selectively blocks the ERK phosphorylation and only affects the cell metabolic activity without the reduction of viable cells. Inhibition of ERK signaling downregulates important metalloproteinases and proinflammatory cytokines, and upregulates some NP markers, suggesting its potential to treat IVD degeneration., (© 2022 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals LLC on behalf of Orthopaedic Research Society.)

Excessive mitochondrial fission in podocytes serves as a central hub for the pathogenesis of diabetic nephropathy (DN), and the thromboxane/prostaglandin receptor (TP receptor) plays a potential role in DN. However, regulation of the TP receptor during mitochondrial dynamics disorder in podocytes remains unknown. Here, we firstly reported novel mechanistic details of TP receptor effects on mitochondrial dynamics in podocytes under diabetic conditions. Expression of the TP receptor was significantly upregulated in podocytes under diabetic conditions both in vivo and in vitro. S18886 attenuated podocyte mitochondrial fission, glomerular injury and renal dysfunction in diabetic mice. Furthermore, inhibition of the TP receptor by both genetic and pharmacological methods dramatically reduced mitochondrial fission and attenuated podocyte injury induced by high glucose through regulating dynamin-related protein 1 (Drp1) phosphorylation and its subsequent translocation to mitochondria. In contrast, TP receptor overexpression and application of TP receptor agonist U46619 in these podocytes showed the opposite effect on mitochondrial fission and podocyte injury. Furthermore, treatment with Y27632, an inhibitor of Rho-associated kinase1 (ROCK1), significantly blunted more fragmented mitochondria and reduced podocyte injuries in podocytes with TP receptor overexpression or after U46619 treatment. Finally, pharmacological inhibition of Drp1 alleviated excessive mitochondrial fragmentation and podocyte damage in TP receptor overexpressing podocytes. Our data suggests that increased expression of the TP receptor can occur in a human cultured podocyte cell line and in podocytes derived from streptozotocin (STZ)-induced diabetic mice, which contributes to mitochondrial excessive fission and podocyte injury via ROCK1-Drp1 signaling., Competing Interests: Declaration of Competing Interest The authors have declared that no competing interest exists., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Skeletal muscle contraction triggers the exercise pressor reflex (EPR) to regulate the cardiovascular system response to exercise. During muscle contraction, substances are released that generate action potential activity in group III and IV afferents that mediate the EPR. Some of these substances increase afferent activity via G-protein-coupled receptor (GPCR) activation, but the mechanisms are incompletely understood. We were interested in determining if tetrodotoxin-resistant (TTX-R) voltage-dependent sodium channels (Na V ) were involved and investigated the effect of a mixture of such compounds (bradykinin, prostaglandin, norepinephrine, and ATP, called muscle metabolites). Using whole cell patch-clamp electrophysiology, we show that the muscle metabolites significantly increased TTX-R Na V currents. The rise time of this enhancement averaged ∼2 min, which suggests the involvement of a diffusible second messenger pathway. The effect of muscle metabolites on the current-voltage relationship, channel activation and inactivation kinetics support Na V 1.9 channels as the target for this enhancement. When applied individually at the concentration used in the mixture, only prostaglandin and bradykinin significantly enhanced Na V current, but the sum of these enhancements was <1/3 that observed when the muscle metabolites were applied together. This suggests synergism between the activated GPCRs to enhance Na V 1.9 current. When applied at a higher concentration, all four substances could enhance the current, which demonstrates that the GPCRs activated by each metabolite can enhance channel activity. The enhancement of Na V 1.9 channel activity is a likely mechanism by which GPCR activation increases action potential activity in afferents generating the EPR. NEW & NOTEWORTHY G-protein-coupled receptor (GPCR) activation increases action potential activity in muscle afferents to produce the exercise pressor reflex (EPR), but the mechanisms are incompletely understood. We provide evidence that Na V 1.9 current is synergistically enhanced by application of a mixture of metabolites potentially released during muscle contraction. The enhancement of Na V 1.9 current is likely one mechanism by which GPCR activation generates the EPR and the inappropriate activation of the EPR in patients with cardiovascular disease.

(Leukaemia derived) dendritic cells (DC, DC leu ) are potent stimulators of anti-leukaemic activity in acute myeloid leukaemia (AML) and can be generated with immunomodulatory kits containing granulocyte-macrophage-colony-stimulating-factor (GM-CSF), prostaglandin-E 1 (PGE 1 ), prostaglandin-E 2 (PGE 2 ) and/or picibanil (OK-321). Potential adverse effects initiated through kits, especially the proliferation of blasts, must be ruled out to ensure treatment safety. We quantified proliferating blasts with the proliferation markers CD71 and Ki-67 and the novel proliferation marker IPO-38 before and after kit treatment ex vivo. IPO-38 hereby appeared to be the most sensitive marker; a combination with CD71 may add value when assessing proliferation kinetics. Kit treatment did not or only slightly (<5%) induce blast proliferation in most cases. An induction of blast proliferation was only found in single cases and could be compensated by DC leu -induced anti-leukaemic activity in most times. Overall, we appraise kit treatment to be safe in vivo., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Modiblast Pharma GmbH (Oberhaching, Germany) holds the European Patent 15,801,987.7–1118 and US Patent 15–517,627 “Use of immunomodulatory effective compositions for the immunotherapeutic treatment of patients suffering from myeloid leukemias”, in which Helga Maria Schmetzer is involved., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Ca 2+ -signaling controls sperm cell functions necessary for successful fertilization. Multiple endocrine disrupting chemicals have been found to interfere with normal Ca 2+ -signaling in human sperm cells through an activation of the sperm-specific CatSper Ca 2+ -channel, which is vital for normal male fertility., Objectives: We investigated 53 pesticides for their ability to interfere with CatSper mediated Ca 2+ -signaling and function in human sperm cells., Methods: Effects of the pesticides on Ca 2+ -signaling in human sperm cells were evaluated using a Ca 2+ -fluorometric assay. Effects via CatSper were assessed using the specific CatSper inhibitor RU1968. Effects on human sperm function and viability were assessed using an image cytometry-based acrosome reaction assay and the modified Kremer's sperm-mucus penetration assay., Results: 28 of 53 pesticides were found to induce Ca 2+ -signals in human sperm cells at 10 µM. The majority of these 28 active pesticides induced Ca 2+ -signals through CatSper and interfered with subsequent Ca 2+ -signals induced by the two endogenous CatSper ligands progesterone and prostaglandin E 1 . Multiple active pesticides were found to affect Ca 2+ -mediated sperm functions and viability at 10 µM. Low nM dose mixtures of the active pesticides alone or in combination with other environmental chemicals were found to significantly induce Ca 2+ -signals and inhibit Ca 2+ -signals induced subsequently by progesterone and prostaglandin E 1 ., Conclusions: Our results show that pesticides, both alone and in low nM dose mixtures, interfere with normal Ca 2+ -signaling in human sperm cells in vitro in low nM concentrations. Biomonitoring of the active pesticides in relevant matrices such as blood and reproductive fluids is very limited and the effects of real time human pesticide exposure on human sperm cells and fertility thus remains largely unknown. To which extent human pesticide exposure affects the chances of a successful fertilization in humans in vivo needs further research., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Sigma-1 receptor (S1R) is detected in different cell types and can regulate intracellular signaling pathways. S1R plays a role in the pathomechanism of diseases and the regulation of neurotransmitters. Fluvoxamine can bind to S1R and reduce the serotonin uptake of neurons and platelets. We therefore hypothesized that platelets express S1R, which can modify platelet function. The expression of the SIGMAR1 gene in rat platelets was examined with a reverse transcription polymerase chain reaction and a quantitative polymerase chain reaction. The receptor was also visualized by immunostaining and confocal laser scanning microscopy. The effect of S1R agonist PRE-084 on the eicosanoid synthesis of isolated rat platelets and ADP- and AA-induced platelet aggregation was examined. S1R was detected in rat platelets both at gene and protein levels. Pretreatment with PRE-084 of resting platelets induced elevation of eicosanoid synthesis. The rate of elevation in thromboxane B 2 and prostaglandin D 2 synthesis was similar, but the production of prostaglandin E 2 was higher. The concentration-response curve showed a sigmoidal form. The most effective concentration of the agonist was 2 µM. PRE-084 increased the quantity of cyclooxygenase-1 as detected by ELISA. PRE-084 also elevated the ADP- and AA-induced platelet aggregation. S1R of platelets might regulate physiological or pathological functions.

Grape juice consumption may influence the early occurrence of ductal constriction during pregnancy, since the consumption of foods rich in polyphenols can be linked to the premature constriction of the ductus arteriosus. This study aimed to evaluate the effect of purple grape juice consumption during gestation on fetal ductus arteriosus closure, prostaglandin levels, and oxidative stress markers in Wistar rats. We divided 18 pregnant rats into four groups: a control group (C), a single-dose grape juice group (SDGJ), a two-dose grape juice group (TDGJ) of 7 μl/g body weight per day, and an indomethacin group (I). Blood was collected on gestational day (GD) 0, 14, and 20. Prostaglandin levels were measured, and the livers and hearts were removed from the mothers and fetuses for oxidative stress analysis; histology of the fetal ductus arteriosus was performed. Prostaglandin levels (pg/ml) at GD 20 were (C:1462.10 ± 314.61); (SDGJ:987.66 ± 86.25); (TDGJ:1290.00 ± 221.57), and (I:584.75 ± 46.77). Fetal ductus arteriosus closure occurred only in the indomethacin group. Lipid peroxidation evaluated through thiobarbituric acid reactive substances (nmol/mg protein) in maternal livers was lower in the grape juice groups (C: 4.11 ± 0.76 nmol/mg protein), (SDGJ: 2.34 ± 0.36), (TDGJ: 1.52 ± 0.18), and (I: 4.20 ± 0.76). Sulfhydryls (nmol/mg protein) were lower in the TDGJ group (C:763.59 ± 61.38 nmol/mg protein), (SDGJ:978.88 ± 158.81), (TDGJ:385.32 ± 86.78), and (I:727.72 ± 49.12). Also, superoxide dismutase activity (USOD/mg protein) was higher in fetal hearts in this group: (C:5.29 ± 0.33), (SDGJ:4.48 ± 0.47), (TDGJ:7.35 ± 0.43), and (I:6.00 ± 0.18). We conclude that grape juice consumption in pregnancy does not induce ductus arteriosus closure in the fetus and presented potential antioxidant effects., (© 2022 Wiley Periodicals LLC.)

Objective: The potential chondroprotective effect of celecoxib, a nonsteroidal anti-inflammatory drug and selective cyclooxygenase-2 inhibitor used to reduce pain and inflammation in knee osteoarthritis patients, is disputed. This study aimed at investigating the chondroprotective effects of celecoxib on (1) human articular cartilage explants and (2) in an in vivo osteoarthritis rat model., Design: Articular cartilage explants from 16 osteoarthritis patients were cultured for 24 hours with celecoxib or vehicle. Secreted prostaglandins (prostaglandin E 2 , prostaglandin F 2α , prostaglandin D 2 ) and thromboxane B2 (TXB2) concentrations were determined in medium by ELISA, and protein regulation was measured with label-free proteomics. Cartilage samples from 7 of these patients were analyzed for gene expression using real-time quantitative polymerase chain reaction. To investigate the chondroprotective effect of celecoxib in vivo , 14 rats received an intra-articular injection of celecoxib or 0.9% NaCl after osteoarthritis induction by anterior cruciate ligament transection and partial medial meniscectomy (ACLT/pMMx model). Histopathological scoring was used to evaluate osteoarthritis severity 12 weeks after injection., Results: Secretion of prostaglandins, target of Nesh-SH3 (ABI3BP), and osteonectin proteins decreased, whereas tissue inhibitor of metalloproteinase 2 (TIMP-2) increased significantly after celecoxib treatment in the human ( ex vivo ) explant culture. Gene expression of a disintegrin and metalloproteinase with thrombospondin motifs 4 and 5 (ADAMTS4/5) and metalloproteinase 13 (MMP13) was significantly reduced after celecoxib treatment in human cartilage explants. Cartilage degeneration was reduced significantly in an in vivo osteoarthritis knee rat model., Conclusions: Our data demonstrated that celecoxib acts chondroprotective on cartilage ex vivo and a single intra-articular bolus injection has a chondroprotective effect in vivo .

Investigation of the relationship between inflammation and energy metabolism is important for understanding biology of chronic noncommunicable diseases. Use of metformin, a drug for treatment of diabetes, is considered as a promising direction for treatment of neurodegenerative diseases and other neuropathologies with an inflammatory component. Astrocytes play an important role in the regulation of energy metabolism and neuroinflammation; therefore, we studied the effect of metformin on the cellular responses of primary rat astrocytes cultured in a medium with high glucose concentration (22.5 mM, 48-h incubation). Lipopolysaccharide (LPS) was used to stimulate inflammation. The effects of metformin were assessed by monitoring changes in the expression of proinflammatory cytokines and synthesis of oxylipins, assayed with ultra-high-performance liquid chromatography and tandem mass spectrometry (UPLC-MS/MS). Changes at the intracellular level were assessed by analyzing phosphorylation of ERK kinase and transcription factor STAT3, as well as enzymes mediating oxylipin synthesis, cyclooxygenase 1 and 2 (COX). It was found that, independent on glucose concentration, metformin reduced the LPS-stimulated release of cytokines IL-1β and IL-6, decreased activity of the transcription factor STAT3, ERK kinase, synthesis of the derivatives of the cyclooxygenase branch of metabolism of oxylipins and anandamide, and did not affect formation of ROS. The study of energy phenotype of the cells showed that metformin activated glycolysis and inhibited mitochondrial respiration and oxidative phosphorylation, independent on LPS stimulation and cell cultivation at high glucose concentration. Thus, it has been shown that metformin exhibits anti-inflammatory effects, and its effect on the synthesis of cytokines, prostaglandins, and other lipid mediators could determine beneficial effects of metformin in models of neuropathology.

The inhibitory effects of docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and linoleic acid (LA) on the contractions induced by five prostanoids and U46619 (a TP receptor agonist) were examined in guinea pig gastric fundus smooth muscle (GFSM). Tension changes were isometrically measured, and the mRNA expression of prostanoid receptors was measured by RT-qPCR. DHA and EPA significantly inhibited contractions induced by the prostanoids and U46619, whereas LA inhibited those induced by prostaglandin D 2 and U46619. The mRNA expression levels of the prostanoid receptors were TP ≈ EP 3  >> FP > EP 1 . The inhibition by DHA, EPA, and LA was positively correlated with that by SQ 29,548 (a TP receptor antagonist) but not with that by L-798,106 (an EP 3 receptor antagonist). DHA and EPA suppressed high KCl-induced contractions by 35% and 25%, respectively, and the contractions induced by the prostanoids and U46619 were suppressed by verapamil, a voltage-dependent Ca 2+ channel (VDCC) inhibitor, by 40%-85%. Although LA did not suppress high KCl-induced contractions, it suppressed U46619-induced contractions in the presence of verapamil. However, LA did not show significant inhibitory effects on U46619-induced Ca 2+ increases in TP receptor-expressing cells. In contrast, LA inhibited U46619-induced contractions in the presence of verapamil, which was also suppressed by SKF-96365 (a store-operated Ca 2+ channel [SOCC] inhibitor). These findings suggest that the TP receptor and VDCC are targets of DHA and EPA to inhibit prostanoid-induced contractions of guinea pig GFSM, and SOCCs play a significant role in LA-induced inhibition of U46619-induced contractions., (© 2022 The Authors. Pharmacology Research & Perspectives published by John Wiley & Sons Ltd, British Pharmacological Society and American Society for Pharmacology and Experimental Therapeutics.)

Transcriptional factor EB (TFEB), a master regulator of autophagy and lysosomal biogenesis, is generally regarded as a pro-survival factor. Here, we identify that besides its effect on autophagy induction, TFEB exerts a pro-apoptotic effect in response to the cyclopentenone prostaglandin 15-deoxy-∆- 12,14 -prostaglandin J2 (15d-PGJ2). Specifically, 15d-PGJ2 promotes TFEB translocation from the cytoplasm into the nucleus to induce autophagy and lysosome biogenesis via reactive oxygen species (ROS) production rather than mTORC1 inactivation. Surprisingly, TFEB promotes rather than inhibits apoptosis in response to 15d-PGJ2. Mechanistically, ROS-mediated TFEB translocation into the nucleus transcriptionally upregulates the expression of ATF4, which is required for apoptosis elicited by 15d-PGJ2. Additionally, inhibition of TFEB activation by ROS scavenger N-acetyl cysteine or inhibition of protein synthesis by cycloheximide effectively compromises ATF4 upregulation and apoptosis in response to 15d-PGJ2. Collectively, these results indicate that ROS-induced TFEB activation exerts a novel role in promoting apoptosis besides its role in regulating autophagy in response to 15d-PGJ2. This work not only evidences how TFEB is activated by 15d-PGJ2, but also unveils a previously unexplored role of ROS-dependent activation of TFEB in modulating cell apoptosis in response to 15d-PGJ2., (© 2021. The Author(s), under exclusive licence to CPS and SIMM.)

Childhood psychological trauma appears to sensitize stress-related neuroinflammatory systems to increase later vulnerability for depression and other stress-related mental disorders. Isolation of guinea pig pups from the maternal attachment figure for 3 h in threatening surroundings leads to a sensitization of inflammatory-mediated, depressive-like behavior and fever during later isolations. A previous study found the non-selective COX inhibitor naproxen administered before the initial isolation moderated depressive-like behavior and its sensitization. Here, we examined effects of naproxen given following early isolation. Male and female guinea pig pups surgically implanted with telemetry devices to measure core temperature were isolated for 3 h on 2 consecutive days near weaning (first isolation Day 20-24). Several days later, they began 4 consecutive days of injection with either saline vehicle or 10 or 20 mg/kg naproxen prior to a third isolation in early adolescence, that is, 10 days after their first isolation. Across the first two isolations, depressive-like behavior and fever sensitized. Both doses of naproxen attenuated depressive-like behavior during the third isolation. Fever was unaffected. Results suggest prostaglandin mediation of sensitization of depressive-like behavioral, but not febrile, responses to subsequent isolation. Findings also support further study of anti-inflammatory treatments to mitigate lasting consequences of early-attachment disruption., (© 2022 Wiley Periodicals LLC.)

The process of gastric ulcer healing includes cell migration, proliferation, angiogenesis and re-epithelialization. Platelets contain angiogenesis stimulating factors that induce angiogenesis. Thromboxane A 2 (TXA 2 ) not only induces platelet activity but also angiogenesis. This study investigated the role of TXA 2 in gastric ulcer healing using TXA 2 receptor knockout (TPKO) mice. Gastric ulcer healing was suppressed by treatment with the TXA 2 synthase inhibitor OKY-046 and the TXA 2 receptor antagonist S-1452 compared with vehicle-treated mice. TPKO showed delayed gastric ulcer healing compared with wild-type mice (WT). The number of microvessels and CD31 expression were lower in TPKO than in WT mice, and TPKO suppressed the expression of transforming growth factor beta (TGF-β) and vascular endothelial growth factor A (VEGF-A) in areas around gastric ulcers. Immunofluorescence assays showed that TGF-β and VEGF-A co-localized with platelets. Gastric ulcer healing was significantly reduced in WT mice transplanted with TPKO compared with WT bone marrow. These results suggested that TP signalling on platelets facilitates gastric ulcer healing through TGF-β and VEGF-A., (© 2021 The Authors. International Journal of Experimental Pathology published by John Wiley & Sons Ltd on behalf of Company of the International Journal of Experimental Pathology (CIJEP).)

To study the additive effects of Rho-associated coiled-coil containing protein kinase inhibitors, ripasudil (Rip) to bimatoprost acid (BIM-A) on orbital adipose tissue, three-dimensional (3D) cultures of human orbital fibroblasts (HOFs) were prepared and the physical properties including the 3D spheroid size and stiffness, lipid staining by BODIPY and the mRNA expression of adipogenesis-related genes, PPARγ and AP2, and extracellular matrix (ECM) including collagen (COL)1, 4 and 6, and fibronectin (FN) were analyzed. Adipogenesis (DIF+) induced (1) enlargement and increasing stiffness of the 3D HOFs spheroid, (2) increased lipid staining, the expression of adipogenesis-related gene expressions, and (3) the down-regulation of COL1 and FN and up-regulation of COL4 and COL6. In the presence of BIM-A, (1) such DIF+-induced changes in 3D spheroid size and stiffness were significantly inhibited or enhanced, respectively, (2) the lipid staining and its related gene expressions were significantly down-regulated, and (3) the expression of COL1 and COL6 were up-regulated. By the addition of Rip to BIM-A, the above BIM-A-induced effects were all inhibited, except for the up-regulation of COL6 and FN expression, that is, enlarging and decreasing stiffness, enhancement of lipid staining and its related gene expression, and down-regulation of COL1 expression. Our present study indicates that Rip significantly suppressed BIM-A-induced effects toward 3D HOFs spheroids., (© 2021. Japan Human Cell Society.)

Prostaglandins (PGs) are lipid mediators derived from arachidonic acid by several enzymes including cyclooxygenase (COX)-1 and COX-2. We have previously shown that PGE 2 regulates immune responses, such as Th1 cytokine production and T-cell proliferation, in cattle. However, it is still unclear whether other PGs are involved in the regulation of immune responses in cattle. Here, immunosuppressive profiles of PGs (PGA 1 , PGB 2 , PGD 2 , PGE 2 , PGF 1α and PGF 2α ) were firstly examined using bovine peripheral blood mononuclear cells (PBMCs). In addition to PGE 2 , PGA 1 significantly inhibited Th1 cytokine production from PBMCs in cattle. Further analyses focusing on PGA 1 revealed that treatment with PGA 1 in the presence of concanavalin A (con A) downregulated CD69, an activation marker, and IFN-γ expression in both CD4 + and CD8 + T cells. Sorted CD3 + T cells stimulated with con A were cultivated with PGA 1 , and IFN-γ and TNF-α concentrations decreased upon PGA 1 treatment. Taken together, these results suggest that the treatment with PGA 1 in vitro inhibits T-cell activation, especially Th1 cytokine production, in cattle., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Ca2+ signalling controls human sperm functions necessary for successful fertilization. Multiple endocrine-disrupting chemicals have been found to activate the CatSper Ca2+ channel and thereby interfering with Ca2+ signalling in human sperm. Finasteride is prescribed to men in the fertile age to treat hair loss and its use has been associated with impaired male fertility. Due to the structural relatedness of finasteride to the endogenous CatSper ligand progesterone, this study aimed to investigate whether finasteride affects human sperm in a progestogen-like manner. The effect of finasteride on Ca2+ signalling via CatSper in human sperm was investigated in cell suspensions by single-cell imaging. Additionally, effects on sperm penetration into viscous medium and acrosome reaction were assessed. Finasteride alone caused a minor transient rise in the intracellular, free Ca2+ concentration ([Ca2+]i) at physiologically relevant concentrations. Ca2+ signals induced by PGE1 were inhibited by finasteride displaying mixed type of inhibition consistent with multiple binding sites. Finasteride did not interfere with progesterone-induced Ca2+ signalling and no effect on acrosome reaction or sperm viability was found. Finasteride significantly decreased PGE1-induced penetration into viscous medium but in concentrations above what is measured in blood and seminal fluids during regular finasteride administration. In conclusion, the use of finasteride may affect Ca2+ signalling in human sperm through an interaction with the PGE1-binding site, but to which extend it alters the chances of a successful fertilization needs further investigation. It remains to be investigated whether finasteride administration may give rise to side effects by interfering with prostaglandin signalling elsewhere in the human body.

Local or systemic inflammation can severely impair urinary bladder functions and contribute to the development of voiding disorders in millions of people worldwide. Isoprostanes are inflammatory lipid mediators that are upregulated in the blood and urine by oxidative stress and may potentially induce detrusor overactivity. The aim of the present study was to investigate the effects and signal transduction of isoprostanes in human and murine urinary bladders in order to provide potential pharmacological targets in detrusor overactivity. Contraction force was measured with a myograph in murine and human urinary bladder smooth muscle (UBSM) ex vivo. Isoprostane 8-iso-PGE 2 and 8-iso-PGF 2α evoked dose-dependent contraction in the murine UBSM, which was abolished in mice deficient in the thromboxane prostanoid (TP) receptor. The responses remained unaltered after removal of the mucosa or incubation with tetrodotoxin. Smooth muscle-specific deletion of Gα 12/13 protein or inhibition of Rho kinase by Y-27632 decreased the contractions. In Gα q/11 -knockout mice, responses were reduced and in the presence of Y-27632 abolished completely. In human UBSM, the TP agonist U-46619 evoked dose-dependent contractions. Neither atropine nor the purinergic receptor antagonist pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid decreased the effect, indicating that TP receptors directly mediate detrusor muscle contraction. 8-iso-PGE 2 and 8-iso-PGF 2α evoked dose-dependent contraction in the human UBSM, and these responses were abolished by the TP antagonist SQ-29548 and were decreased by Y-27632. Our results indicate that isoprostanes evoke contraction in murine and human urinary bladders, an effect mediated by the TP receptor. The G 12/13 -Rho-Rho kinase pathway plays a significant role in mediating the contraction and therefore may be a potential therapeutic target in detrusor overactivity. NEW & NOTEWORTHY Voiding disorders affect millions of people worldwide. Inflammation can impair urinary bladder functions and contribute to the development of detrusor overactivity. The effects and signal transduction of inflammatory lipid mediator isoprostanes were studied in human and murine urinary bladders ex vivo. We found that isoprostanes evoke contraction, an effect mediated by thromboxane prostanoid receptors. The G 12/13 -Rho-Rho kinase signaling pathway plays a significant role in mediating the contraction and therefore may be a potential therapeutic target.

Background: Postpartum hemorrhage (PPH) remains a common cause of maternal mortality worldwide. Medical intervention plays an important role in the prevention and treatment of PPH. Prostaglandins (PGs) are currently recommended as second-line uterotonics, which are applied in cases of persistent bleeding despite oxytocin treatment., Summary: PG agents that are constantly used in clinical practice include carboprost, sulprostone, and misoprostol, representing the analogs of PGF2α, PGE2, and PGE1, respectively. Injectable PGs, when used to treat PPH, are effective in reducing blood loss but probably induce cardiovascular or respiratory side effects. Misoprostol is characterized by oral administration, low cost, stability in storage, broad availability, and minimal side effects. It remains a treatment option for uterine atony in low-resource settings, but its effectiveness as a uterotonic for independent application may be limited. Key Messages: The present review article discusses the physiological roles of various natural PGs, evaluates the existing evidence of PG analogs in the prevention and treatment of PPH, and finally provides a reference to assist obstetricians in selecting appropriate uterotonics., (© 2021 The Author(s) Published by S. Karger AG, Basel.)

Until recently, Nurr1 (NR4A2) was known as an orphan nuclear receptor without a canonical ligand-binding domain, featuring instead a narrow and tight cavity for small molecular ligands to bind. In-depth characterization of its ligand-binding pocket revealed that it is highly dynamic, with its structural conformation changing more than twice on the microsecond-to-millisecond timescale. This observation suggests the possibility that certain ligands are able to squeeze into this narrow space, inducing a conformational change to create an accessible cavity. The cocrystallographic structure of Nurr1 bound to endogenous ligands such as prostaglandin E1/A1 and 5,6-dihydroxyindole contributed to clarifying the crucial roles of Nurr1 and opening new avenues for therapeutic interventions for neurodegenerative and/or inflammatory diseases related to Nurr1. This review introduces novel endogenous and synthetic Nurr1 agonists and discusses their potential effects in Nurr1-related diseases.

Prostanoids are bioactive lipid mediators and take part in many physiological and pathophysiological processes in practically every organ, tissue and cell, including the vascular, renal, gastrointestinal and reproductive systems. In this review, we focus on their influence on platelets, which are key elements in thrombosis and hemostasis. The function of platelets is influenced by mediators in the blood and the vascular wall. Activated platelets aggregate and release bioactive substances, thereby activating further neighbored platelets, which finally can lead to the formation of thrombi. Prostanoids regulate the function of blood platelets by both activating or inhibiting and so are involved in hemostasis. Each prostanoid has a unique activity profile and, thus, a specific profile of action. This article reviews the effects of the following prostanoids: prostaglandin-D 2 (PGD 2 ), prostaglandin-E 1 , -E 2 and E 3 (PGE 1 , PGE 2 , PGE 3 ), prostaglandin F 2α (PGF 2α ), prostacyclin (PGI 2 ) and thromboxane-A 2 (TXA 2 ) on platelet activation and aggregation via their respective receptors.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of the novel coronavirus disease 2019 (COVID-19), a highly pathogenic and sometimes fatal respiratory disease responsible for the current 2020 global pandemic. Presently, there remains no effective vaccine or efficient treatment strategies against COVID-19. Non-steroidal anti-inflammatory drugs (NSAIDs) are medicines very widely used to alleviate fever, pain, and inflammation (common symptoms of COVID-19 patients) through effectively blocking production of prostaglandins (PGs) via inhibition of cyclooxyganase enzymes. PGs can exert either proinflammatory or anti-inflammatory effects depending on the inflammatory scenario. In this review, we survey the potential roles that NSAIDs and PGs may play during SARS-CoV-2 infection and the development and progression of COVID-19. LINKED ARTICLES: This article is part of a themed issue on The Pharmacology of COVID-19. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.21/issuetoc., (© 2020 The Authors. British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)

Male olfactory cues may guide aggregation on spawning reefs, mate evaluation and synchronized gamete release in lake trout Salvelinus namaycush, but a lack of information on the source and identity of the cues precludes direct tests of their function. Using a two-channel flume, we found ovulated female lake trout increased time spent in the channel treated with spermiated male-conditioned water, urine and bile but not synthesized prostaglandin F 2α . We suggest future efforts to characterize male olfactory cues focus on urine and postulate that bile acids contribute to its behavioural activity., (© 2020 Fisheries Society of the British Isles.)

An increasing number of studies have shown that prostaglandins (PGs) exert multiple regulatory actions in the processes associated to tissue remodeling and fibrosis. Extracellular matrix (ECM) turnover is mediated by matrix metallopeptidases (MMPs). The knowledge about the regulation of their expression in mare endometrium is still limited. Thus, the aim of this study was to investigate whether: (i) profibrotic transforming growth factor (TGF)-β1 modulates PG production in equine endometrium; and (ii) PGE 2 and PGF 2α modulate MMPs, their tissue inhibitors (TIMPs), and collagen 1 (COL1) expression. In experiment 1, the effect of TGF-β1 (5 ng/mL) on PG secretion and PG synthases mRNA transcription, after 24 and 48 h treatment of mare endometrial fibroblast and epithelial cells was investigated using ELISA and qPCR. In experiment 2, the effects of PGE 2 and PGF 2α  in doses 10 -7 M and 10 -8 M on secretion and MMP1, 2, 9, 13, TIMP1, 2, and COL1A1 mRNA transcription in mare endometrial fibroblasts were assessed. Transforming growth factor-β1 treatment decreased secretion of PGF 2α by endometrial fibroblasts (P < 0.05) and PGF 2α and PGE 2 by endometrial epithelial cells (P < 0.05). Prostaglandin E 2 increased MMP-2 and MMP-9, and decreased MMP-13 secretion by endometrial fibroblasts (P < 0.05). Additionally, PGF 2α treatment increased MMP-2, MMP-13 and COL1, but decreased MMP-1 secretion by endometrial fibroblasts (P < 0.05). Prostaglandins may be involved in the processes associated to pathological endometrial remodeling by their effect on MMP expression. The effect of PGF 2α on COL1 secretion from fibroblasts suggests its profibrotic role in pathological endometrial remodeling., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

The cyclopentenone prostaglandins (CyPGs) are a small group compounds that are a subset of the eicosanoid superfamily, which are metabolites of arachidonic acid as well as other polyunsaturated fatty acids. The CyPGs are defined by a structural feature, namely, a five-membered carbocyclic ring containing an alfa-beta unsaturated keto group. The two most studied members are PGA 2 and 15d-PGJ 2 (15-deoxy-Δ12,14-prostaglandin J 2 ); other less studied members are PGA 1 , Δ 12 -PGJ 2 , and PGJ 2 . They are involved in a number of biological activities including the ability to resolve chronic inflammation and the growth and survival of cells, particularly those of cancerous or neurological origin. Also, they can activate the prostaglandin DP2 receptor as well as the ligand-dependent transcription factor PPAR-gamma. Their ability to promote the resolution of chronic inflammation makes it of particular interest to have a good understanding of their actions. Since their discovery, the literature on the CyPGs has greatly expanded both in size and in scope; these reports are covered in the current review., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Peptic ulcer disease, the most common gastrointestinal disorder, is currently treated with several types of drugs, but all have severe side effects. The aim of the present study was to evaluate the gastroprotective activity of juanislamin, isolated from Calea urticifolia , in a rat model of ethanol-induced gastric lesions. Thirty minutes after orally administering a given dose of juanislamin (from 1 to 30 mg/kg) or carbenoxolone (the reference drug, at 1-100 mg/kg) to rats, 1 mL of ethanol was applied, and the animals were sacrificed 2 h later. The stomachs were removed and opened to measure the total area of lesions in each. To examine the possible participation of prostaglandins, nitric oxide and/or sulfhydryl groups in the mechanism of action of juanislamin, the rats received indomethacin, NG-Nitro-l-arginine methyl ester hydrochloride (l-NAME) or N -ethylmaleimide pretreatment, respectively, before being given juanislamin and undergoing the rest of the methodology. Juanislamin inhibited gastric lesions produced by ethanol in a non-dose-dependent manner, showing the maximum gastroprotective effect (100%) at 10 mg/kg. The activity of juanislamin was not modified by pretreatment with indomethacin, l-NAME or N -ethylmaleimide. In conclusion, juanislamin protected the gastric mucosa from ethanol-induced damage, and its mechanism of action apparently does not involve prostaglandins, nitric oxide or sulfhydryl groups.

The plasmas of diabetic or uremic patients and of those receiving peritoneal dialysis treatment have increased levels of the glucose-derived dicarbonyl metabolites like methylglyoxal (MGO), glyoxal (GO), and 3-deoxyglucosone (3-DG). The elevated dicarbonyl levels can contribute to the development of painful neuropathies. Here, we used stimulated immunoreactive Calcitonin Gene-Related Peptide (iCGRP) release as a measure of nociceptor activation, and we found that each dicarbonyl metabolite induces a concentration-, TRPA1-, and Ca 2+ -dependent iCGRP release. MGO, GO, and 3-DG were about equally potent in the millimolar range. We hypothesized that another dicarbonyl, 3,4-dideoxyglucosone-3-ene (3,4-DGE), which is present in peritoneal dialysis (PD) solutions after heat sterilization, activates nociceptors. We also showed that at body temperatures 3,4-DGE is formed from 3-DG and that concentrations of 3,4-DGE in the micromolar range effectively induced iCGRP release from isolated murine skin. In a novel preparation of the isolated parietal peritoneum PD fluid or 3,4-DGE alone, at concentrations found in PD solutions, stimulated iCGRP release. We also tested whether inflammatory tissue conditions synergize with dicarbonyls to induce iCGRP release from isolated skin. Application of MGO together with bradykinin or prostaglandin E 2 resulted in an overadditive effect on iCGRP release, whereas MGO applied at a pH of 5.2 resulted in reduced release, probably due to an MGO-mediated inhibition of transient receptor potential (TRP) V1 receptors. These results indicate that several reactive dicarbonyls activate nociceptors and potentiate inflammatory mediators. Our findings underline the roles of dicarbonyls and TRPA1 receptors in causing pain during diabetes or renal disease., (© 2020 Becker et al.)

Background: Methyl nicotinate (MN) induces a local cutaneous erythema in the skin and may be valuable as a local provocation in the assessment of microcirculation and skin viability. The mechanisms through which MN mediates its vascular effect are not fully known. The aim of this study was to characterize the vasodilatory effects of topically applied MN and to study the involvement of nitric oxide (NO), local sensory nerves, and prostaglandin-mediated pathways., Methods: MN was applied on the skin of healthy subjects in which NO-mediated (L-NMMA), nerve-mediated (lidocaine/prilocaine), and cyclooxygenase-mediated (NSAID) pathways were selectively inhibited. Microvascular responses in the skin were measured using laser speckle contrast imaging (LSCI)., Results: NSAID reduced the MN-induced perfusion increase with 82% (P < .01), whereas lidocaine/prilocaine reduced it with 32% (P < .01). L-NMMA did not affect the microvascular response to MN., Conclusion: The prostaglandin pathway and local sensory nerves are involved in the vasodilatory actions of MN in the skin., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Spontaneous, recurrent spreading depolarizations (SD) are increasingly more appreciated as a pathomechanism behind ischemic brain injuries. Although the prostaglandin F2α - FP receptor signaling pathway has been proposed to contribute to neurodegeneration, it has remained unexplored whether FP receptors are implicated in SD or the coupled cerebral blood flow (CBF) response. We set out here to test the hypothesis that FP receptor blockade may achieve neuroprotection by the inhibition of SD. Global forebrain ischemia/reperfusion was induced in anesthetized rats by the bilateral occlusion and later release of the common carotid arteries. An FP receptor antagonist (AL-8810; 1 mg/bwkg) or its vehicle were administered via the femoral vein 10 min later. Two open craniotomies on the right parietal bone served the elicitation of SD with 1 M KCl, and the acquisition of local field potential. CBF was monitored with laser speckle contrast imaging over the thinned parietal bone. Apoptosis and microglia activation, as well as FP receptor localization were evaluated with immunohistochemistry. The data demonstrate that the antagonism of FP receptors suppressed SD in the ischemic rat cerebral cortex and reduced the duration of recurrent SDs by facilitating repolarization. In parallel, FP receptor antagonism improved perfusion in the ischemic cerebral cortex, and attenuated hypoemic CBF responses associated with SD. Further, FP receptor antagonism appeared to restrain apoptotic cell death related to SD recurrence. In summary, the antagonism of FP receptors (located at the neuro-vascular unit, neurons, astrocytes and microglia) emerges as a promising approach to inhibit the evolution of SDs in cerebral ischemia., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020. Published by Elsevier Inc.)

Oxidized lipids play a critical role in a variety of diseases with two faces: pro- and anti-inflammatory. The molecular mechanisms of this Janus-faced activity remain largely unknown. Here, we have identified that cyclopentenone-containing prostaglandins such as 15d-PGJ2 and structurally related oxidized phospholipid species possess a dual and opposing bioactivity in inflammation, depending on their concentration. Exposure of dendritic cells (DCs)/macrophages to low concentrations of such lipids before Toll-like receptor (TLR) stimulation instigates an anti-inflammatory response mediated by nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent inhibition of nuclear factor κB (NF-κB) activation and downstream targets. By contrast, high concentrations of such lipids upon TLR activation of DCs/macrophages result in inflammatory apoptosis characterized by mitochondrial depolarization and caspase-8-mediated interleukin (IL)-1β maturation independently of Nrf2 and the classical inflammasome pathway. These results uncover unexpected pro- and anti-inflammatory activities of physiologically relevant lipid species generated by enzymatic and non-enzymatic oxidation dependent on their concentration, a phenomenon known as hormesis., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved.)

For many years, the only pharmacological option for patients with critical limb ischemia (CLI) unsuitable for revascularization has been prostanoids; however, some recent guidelines have become very restrictive regarding their use. We review the available evidence on the use of prostanoids and analyze the guideline positions as well as the possible reasons for changes over time. In most placebo-controlled trials and meta-analyses, prostanoids showed a significant effect in improving rest pain, promoting ulcer healing and reducing major amputations. Results for iloprost were especially consistent. Different prostanoid drugs have different evidence of efficacy, thus using a generic term "prostanoids" is misleading. Unfortunately, the available evidence is often of low quality and probably not sufficient to support an extensive use of prostanoids in all patients, and further high-quality randomized trials are needed. Consequently, some recent guidelines do not recommend treatment with prostanoids in this setting. However, in our opinion, pending definitive evidence, patients with CLI who have a viable limb in whom revascularization is unfeasible or has a poor chance of success, without alternative to amputation, may benefit from treatment with iloprost, balancing harms and benefits in each case.

Prostaglandin A 2 -AcMe ( 1 ) and Prostaglandin A 2 ( 2 ) were isolated from the octocoral Plexaura homomalla and three semisynthetic derivatives ( 3 - 5 ) were then obtained using a reduction protocol. All compounds were identified through one- and two-dimensional (1D and 2D) nuclear magnetic resonance (NMR) experiments. Additionally, evaluation of in vitro cytotoxic activity against the breast (MDA-MB-213) and lung (A549) cancer cell lines, in combination with enzymatic activity and molecular docking studies with the enzymes p38α-kinase, Src-kinase, and topoisomerase IIα, were carried out for compounds 1 - 5 in order to explore their potential as inhibitors of cancer-related molecular targets. Results showed that prostaglandin A 2 ( 2 ) was the most potent compound with an IC 50 of 16.46 and 25.20 μg/mL against MDA-MB-213 and A549 cell lines, respectively. In addition, this compound also inhibited p38α-kinase in 49% and Src-kinase in 59% at 2.5 μM, whereas topoisomerase IIα was inhibited in 64% at 10 μM. Enzymatic activity was found to be consistent with molecular docking simulations, since compound 2 also showed the lowest docking scores against the topoisomerase IIα and Src-kinase (-8.7 and -8.9 kcal/mol, respectively). Thus, molecular docking led to establish some insights into the predicted binding modes. Results suggest that prostaglandin 2 can be considered as a potential lead for development inhibitors against some enzymes present in cancer processes.

Although recognized to have an in vivo vasodepressor effect blunted by the vasoconstrictor effect of E-prostanoid receptor-3 (EP3), prostaglandin E 2 (PGE 2 ) evokes contractions of many vascular beds that are sensitive to antagonizing the thromboxane prostanoid receptor (TP). This study aimed to determine the direct effect of PGE 2 on renal arteries and/or the whole renal vasculature and how each of these two receptors is involved in the responses. Experiments were performed on isolated vessels and perfused kidneys of wild-type mice and/or mice with deficiency in TP (TP -/- ), EP3 (EP3 -/- ), or both TP and EP3 (TP -/- /EP3 -/- ). Here we show that PGE 2 (0.001-30 μM) evoked not only contraction of main renal arteries, but also a decrease of flow in perfused kidneys. EP3 -/- diminished the response to 0.001-0.3 μM PGE 2 , while TP -/- reduced that to the prostanoid of higher concentrations. In TP -/- /EP3 -/- vessels and perfused kidneys, PGE 2 did not evoke contraction but instead resulted in vasodilator responses. These results demonstrate that PGE 2 functions as an overall direct vasoconstrictor of the mouse renal vasculature with an effect reflecting the vasoconstrictor activities outweighing that of dilation. Also, our results suggest that EP3 dominates the vasoconstrictor effect of PGE 2 of low concentrations (≤0.001-0.3 μM), but its effect is further added by that of TP, which has a higher efficacy, although activated by higher concentrations (from 0.01 μM) of the same prostanoid PGE 2 ., (© 2019 Federation of American Societies for Experimental Biology.)