FP Receptor Research Articles

Therapeutic Efficacy of Wet Cupping on Uterine Inflammation in Primary Dysmenorrhea: An In Vivo Investigation Targeting Bilateral L4/L5 Vertebrae

Primary dysmenorrhea (PD) is a prevalent problem in gynecology affecting the quality of life for young women. This medical condition is often responsible for the absence of young women from school or work, increasing the risk of developing hyperemesis gravidarum in the future. Furthermore, PD causes pain due to the activation of the local PGF2α pathway in the endometrium, which triggers oxidative stress processes, uterine ischemia and spasmodic uterine contractions. The first-line therapies for PD, Nonsteroid anti-inflammatory drugs (NSAIDs) and oral contraceptives, can cause side effects such as headache, nausea, intestinal ulcers and platelet abnormalities. To overcome the impact of PD, cupping has been proven effective as an alternative pain therapy with minimal side effects. Therefore, this study aimed to evaluate the effects of cupping on writing latency threshold time, PGF2α levels and FP receptor expression in PD model rats. The experiment was conducted using female Sprague Dawley rats to analyze the effects of wet cupping therapy (WCT) on inflammatory repair in the uterus. The method used was a pre- and post-test control group design, with 35 female rats randomly divided into 5 groups. These consisted of normal control (NC), negative control (C−), positive control (C+) + ibuprofen 7.2 mg, as well as treatment groups, comprising dry cupping (DC) and WCT. The results showed that writhing time threshold of WCT was the same as C+ (p = 0.368), while PGF2α decreased in DC (43.43 pg/mL, p = 0.008) and WCT (189.25 pg/mL, p = 0.0154). Similar to C+, WCT significantly decreased serum PGF2α levels compared to C−. WCT also influenced the expression of PTGFR subunit similarly to NC, showing the capacity to control the inflammatory pathway. The study suggested that WCT was a promising therapeutic strategy for PD by decreasing PGF2α and PTGFR expression. HIGHLIGHTS Previous investigations conducted on experimental animals using wet cupping therapy (WCT) have shown histopathological results associated with primary dysmenorrhea (PD) caused by estradiol benzoate and oxytocin. Moreover, this study shows the potential of WCT in reducing inflammation-induced PD pain by inhibiting the expression of PGF2α and PTGFR in the cyclooxygenase pathway, potentially increasing the pain threshold. The results show that WCT offers a potential alternative therapy for PD caused by estradiol benzoate and oxytocin. GRAPHICAL ABSTRACT

Near Add Power of Glaucoma Patients with Early Presbyopia.

Purpose: Glaucoma medication may accelerate the progression of presbyopia. The aim of this study was to compare presbyopia between controls and patients with glaucoma in their 40s. Methods: This was a cross-sectional study of bilateral phakic participants aged between 40 and 49, which included controls (n = 114, mean age 46.1 ± 2.7 y) and patients with primary open-angle glaucoma (n = 105, 46.4 ± 2.7 y) who had been using FP receptor agonists, beta blockers, and carbonic anhydrase inhibitors for at least six months. We compared the near add power between the two groups. Results: The mean near add power and the prevalence of symptomatic presbyopia (near add power ≥ 1.50 D) were 1.16 ± 0.74 D and 42.1% for controls and 1.77 ± 0.71 D (p < 0.01) and 79.0% (p < 0.01) for glaucoma patients, respectively. The odds ratio (OR) and confidence interval for symptomatic presbyopia were associated with age (1.36, 1.21-1.52), ganglion cell complex thickness (0.96, 0.94-0.99), presence of glaucoma (6.19, 3.13-12.23), and number of glaucoma medications (4.26, 2.42-7.43). Among medications, only FP receptor agonists (5.79, 2.68-12.32) produced significant results. Survival analysis showed that glaucoma patients reached the threshold of a near add power of +1.50 D significantly sooner than controls (p < 0.05; log-rank test). Conclusions: Glaucoma patients, especially those using FP receptor agonists, had higher near add power than controls.

Postpartum acute myometritis suppresses expression of contraction-associated proteins in the gravid uterus

Uterine atony is a major contributor to postpartum hemorrhage. We previously proposed the novel histological concept of postpartum acute myometritis (PAM) to elucidate the pathophysiology of uterine atony. This concept involves the infiltration of macrophages and neutrophils, as well as mast cell and complement activation in the myometrium. However, the pathological mechanism underlying uterine atony in the context of PAM remains unclear. Herein, we focused on uterine contraction-associated proteins (CAPs) including connexin 43 (Cx43), oxytocin receptors (OXR), prostaglandin receptors EP1, EP3, FP, and protease-activated receptor (PAR)-1. This follow-up study aimed to compare CAP expression between PAM and control groups. We selected 38 PAM subjects from the cases enrolled in our amniotic fluid embolism registry between 2011 and 2018. Control tissues from 10 parturients were collected during cesarean section. We stained the myometrial tissues with the following CAP markers, inflammatory cell markers, and other markers: Cx43, OXR, EP1, EP3, FP, PAR-1, C5a receptor, tryptase, neutrophil elastase, CD68, β-actin, and Na+/K+-ATPase. The immunostaining-positive areas of Cx43, OXR, EP1, EP3, and FP standardized by β-actin in the PAM tissue were significantly smaller than in the control group, whereas those of PAR-1 and Na+/K+-ATPase increased significantly in the PAM group. The Cx43- and OXR-positive areas correlated negatively with the immunostaining-positive cell numbers of CD68 and tryptase with halo, respectively. PAM may impair individual and synchronized myocyte contraction, leading to uterine atony refractory to uterotonics. Further cell-based studies are needed to elucidate the molecular mechanism by which inflammatory cells suppress CAP expression.

Subconjunctival Administration of an Adeno-Associated Virus Expressing Stanniocalcin-1 Provides Sustained Intraocular Pressure Reduction in Mice

PurposeTo investigate subconjunctival administration of a single-stranded, adeno-associated virus, serotype 2, engineered to express Stanniocalcin-1 with a FLAG tag (ssAAV2-STC-1-FLAG) as a novel sustained intraocular pressure (IOP) lowering agent with a reduced ocular surface side effect profile. DesignIn vivo pre-clinical investigation in mice SubjectsC57BL/6J, DBA/2J, FP receptor knockout mice MethodsNormotensive C57BL/6J mice were treated with a subconjunctival injection of ssAAV2-STC-1-FLAG (2 μL; 6 x 109 viral genomes [VGs]) in one eye and the same volume and concentration of ssAAV2-GFP or the same volume of PBS in the fellow eye. Ocular hypertensive DBA/2J mice were subconjunctivally injected with 6 x 109 VGs of ssAAV2-STC-1-FLAG or ssAAV2-GFP. Steroid-mediated ocular hypertension was induced in C57BL/6J mice with weekly injections of dexamethasone into the conjunctival fornix, and mice were then injected subconjunctivally with 6 x 109 VGs of ssAAV2-STC-1-FLAG or ssAAV2-GFP. FP receptor knockout mice were injected subconjunctivally with 6 x 109 VGs of ssAAV2-STC-1-FLAG or PBS. An identical vector was constructed without the FLAG tag (ssAAV2-STC-1) and evaluated in normotensive C57BL/6J mice. IOP was assessed using the Tonolab tonometer for all experiments. Tumor necrosis factor alpha (TNFα), a marker of ocular surface inflammation, was compared between subconjunctivally delivered ssAAV2-STC-1 and other treatments including daily topical latanoprost. Main outcome measuresIOP assessment ResultsSubconjunctival delivery of ssAAV2-STC-1-FLAG significantly reduced IOP for 10 weeks post injection in normotensive mice. Maximal IOP reduction was seen at week 2 post injection (17.4%; 17.1 ± 0.8 vs 14.1 ± 0.8 mmHg, P<0.001). After the IOP-lowering effect had waned, a second injection restored the ocular hypotensive effect. Subconjunctivally delivered ssAAV2-STC-1-FLAG lowered IOP in DBA/2J mice (16.9%; 17.8 ± 2.0 vs 14.8 ± 0.9 mmHg, P<0.001) and steroid-mediated ocular hypertensive mice (19.4%; 18.7 ±0.9 vs 15.1 ± 0.5 mmHg, P<0.001) over the experimental period. This construct also reduced IOP to a similar extent in wild type (15.9%) and FP receptor knockout (15.7%) mice compared to the fellow eye. A related construct also lowered IOP without the FLAG tag in a similar manner. Reduction in conjunctival TNFα was seen when comparing subconjunctivally delivered ssAAV2-STC-1-FLAG to daily topical latanoprost. ConclusionsSubconjunctival delivery of the STC-1 transgene with a vector system may represent a novel treatment strategy for sustained IOP reduction and improved ocular tolerability that also avoids the daily dosing requirements of currently available medications.

Prostaglandin F2 Receptor Negative Regulator (PTGFRN) Expression Correlates With a Metastatic-like Phenotype in Epidermoid Carcinoma, Pediatric Medulloblastoma, and Mesothelioma.

Prostaglandin F2 receptor negative regulator (PTGFRN) is a transmembrane protein associated with metastatic characteristics of certain cancer types. However, it remains poorly characterized and its direct function in cancer remains unclear. The study presented here aims to further examine whether PTGFRN expression affects a cancer cell's phenotype, as well as metastatic-like characteristics. We used stable shRNA and cDNA transfections to respectively knockdown and overexpress PTGFRN in three different cancer cell lines, two of which are representative of rare and aggressive cancers (Mesothelioma and Pediatric Medulloblastoma). We then examined the characteristics of the resulting clones and showed a decrease in proliferation, migration, colony formation, and spheroid growth capabilities in cells where PTGFRN expression had been inhibited, while cells overexpressing PTGFRN showed the opposite. In addition, we showed that PTGFRN displayed direct binding to two protein partners, Integrin β1 and E. Cadherin, the latter of which is a novel direct binding partner to PTGFRN. Furthermore, silencing PTGFRN expression impacted the cellular process of autophagy, thereby providing another avenue by which PTGFRN potentially contributes to a cancer cell phenotype. Our findings demonstrate the potential role of PTGFRN in cancer metastasis and suggest PTGFRN as a future target for drug development in the treatment of metastatic cancers.

Female Type 1 Diabetic Akita Mice Demonstrate Increased Bladder Contractility via FP Receptor Activation due to NLRP3-Mediated Inflammation.

Diabetic bladder dysfunction (DBD) is driven in part by inflammation which dysregulates prostaglandin release in the bladder. Precise inflammatory mechanisms responsible for such dysregulation have been elusive. Since prostaglandins impact bladder contractility, elucidating these mechanisms may yield potential therapeutic targets for DBD. In female Type 1 diabetic Akita mice, inflammation mediated by the nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) inflammasome is responsible for DBD. Here, we utilized female Akita mice crossbred with NLRP3 knock-out mice to determine how NLRP3-driven inflammation impacts prostaglandin release within the bladder and prostaglandin-mediated bladder contractions. Akita mice were crossbred with NLRP3-⁣/- mice to yield four groups of non-diabetics and diabetics with and without the NLRP3 gene. Females were aged to 30 weeks when Akitas typically exhibit DBD. Urothelia and detrusors were stretched ex vivo to release prostaglandins. Prostaglandin E2 (PGE2) and prostaglandin F2α (PGF2α) were quantified using enzyme linked immunosorbent assays (ELISA). In separate samples, ex vivo contractile force to PGE2 and PGF2α +/- the prostaglandin F (FP) receptor antagonist, AL8810, was measured. FP receptor protein expression was determined via western blotting. Stretch-induced PGE2 release increases in urothelia but decreases in detrusors of diabetics. However, PGE2-mediated bladder contractions are not impacted. Conversely, diabetics show no changes in PGF2α release, but PGF2α-mediated contractions increase significantly. This is likely due to signaling through the FP receptors as FP receptor antagonism prevents this increase and diabetics demonstrate a four-fold increase in FP receptor proteins. Without NLRP3-mediated inflammation, changes in prostaglandin release, contractility, and receptor expression do not occur. NLRP3-dependent inflammation dysregulates prostaglandin release and prostaglandin-mediated bladder contractions in diabetic female Akita mice via FP receptor upregulation.

The Effect of an Elevated Dietary Copper Level on the Vascular Contractility and Oxidative Stress in Middle-Aged Rats.

Copper (Cu), being an essential mineral, plays a crucial role in maintaining physiological homeostasis across multiple bodily systems, notably the cardiovascular system. However, an increased Cu level in the body may cause blood vessel dysfunction and oxidative stress, which is unfavorable for the cardiovascular system. Middle-aged (7-8 months old) male Wistar rats (n/group = 12) received a diet supplemented with 6.45 mg Cu/kg (100% of the recommended daily dietary quantity of copper) for 8 weeks (Group A). The experimental group received 12.9 mg Cu/kg of diet (200%-Group B). An ex vivo study revealed that supplementation with 200% Cu decreased the contraction of isolated aortic rings to noradrenaline (0.7-fold) through FP receptor modulation. Vasodilation to sodium nitroprusside (1.10-fold) and acetylcholine (1.13-fold) was potentiated due to the increased net effect of prostacyclin derived from cyclooxygenase-1. Nitric oxide (NO, 2.08-fold), superoxide anion (O2•-, 1.5-fold), and hydrogen peroxide (H2O2, 2.33-fold) measured in the aortic rings increased. Blood serum antioxidant status (TAS, 1.6-fold), Cu (1.2-fold), Zn (1.1-fold), and the Cu/Zn ratio (1.4-fold) increased. An increase in Cu (1.12-fold) and the Cu/Zn ratio (1.09-fold) was also seen in the rats' livers. Meanwhile, cyclooxygenase-1 (0.7-fold), cyclooxygenase-2 (0.4-fold) and glyceraldehyde 3-phosphate dehydrogenase (0.5-fold) decreased. Moreover, a negative correlation between Cu and Zn was found (r = -0.80) in rat serum. Supplementation with 200% Cu did not modify the isolated heart functioning. No significant difference was found in the body weight, fat/lean body ratio, and organ weight for either the heart or liver, spleen, kidney, and brain. Neither Fe nor Se, the Cu/Se ratio, the Se/Zn ratio (in serum and liver), heme oxygenase-1 (HO-1), endothelial nitric oxide synthase (eNOS), or intercellular adhesion molecule-1 (iCAM-1) (in serum) were modified. Supplementation with 200% of Cu potentiated pro-oxidant status and modified vascular contractility in middle-aged rats.

Effect of PTFGRN Expression on the Proteomic Profile of A431 Cells and Determination of the PTGFRN Interactome.

Prostaglandin F2 receptor negative regulator (PTGFRN) is a transmembrane protein whose expression has been previously implicated in cancer metastasis. However, the exact molecular mechanisms by which PTGFRN influences cancer progression are still unknown. As such, our laboratory set out to investigate how PTGFRN knockdown affected the expression of other proteins. We also carried out coimmunoprecipitation experiments using a monoclonal anti-PTGFRN antibody. We employed mass spectrometry-based proteomics for both experiments to identify proteins that were associated with PTGFRN. Our data show that PTGFRN knockdown increased pathways related to innate immune responses and decreased pathways associated with the synthesis of metabolic precursors and protein processing, among others. Additionally, the coimmunoprecipitation experiments indicated that PTGFRN is associated with proteins involved in processing and metabolism, as well as VEGF signaling molecules. These results highlight the role of PTGFRN as a protein processing regulator, which may be influencing cancer progression.

Unraveling the surface marker signature of cell-derived vesicles via proteome analysis and nanoparticle flow cytometry

The cell-derived vesicles (CDVs) obtained using a proprietary extrusion process are the foundation of BioDrone platform technology. With superior productivity and versatility, this technology has garnered increasing attention in broad applications, particularly as a drug delivery vehicle. Previously, we showed that CDVs exhibited varying levels of expression for tetraspanin and organelle membrane markers while revealing no discernible differences in physical characteristics compared to naturally produced extracellular vesicles (EVs). To further understand and utilize the therapeutic potentials of CDVs, a more comprehensive study of membrane protein profiles is necessary. In addition, it is crucial to validate that the CDVs produced from extrusion are indeed intact lipid vesicles rather than other impurities. Here, we produced multiple batches of CDVs and EVs from HEK293 cells. CDVs and EVs were subjected to the same purification processes for subsequent proteome and particle analyses. The proteome analyses revealed unique proteome signatures between CDVs, EVs, and parental cells. Extensive proteome analyses identified the nine most prominent membrane markers that are abundant in CDVs compared to cells and EVs. Subsequent western blotting and nanoparticle flow cytometry analyses confirmed that CD63, lysosome-associated membrane glycoprotein 1 (LAMP1), and nicastrin (NCSTN) are highly enriched in CDVs, whereas CD81, CD9, and prostaglandin F2 receptor negative regulator (PTGFRN) are more abundant in EVs. This highlights the unique membrane composition and marker signature of CDVs that are distinct from EVs. Lastly, we demonstrated that more than 90% of the CDVs are genuine lipid vesicles by combining two different classes of vesicle labeling dyes and detergents to disrupt lipid membranes. This indicates that our proprietary extrusion technology is highly compatible with other well-characterized EV production methods. The robust CDV markers identified in this study will also facilitate the engineering of CDVs to achieve enhanced therapeutic effects or tissue-selective cargo delivery.

The concept of gene therapy for glaucoma: the dream that has not come true yet.

Gene therapies, despite of being a relatively new therapeutic approach, have a potential to become an important alternative to current treatment strategies in glaucoma. Since glaucoma is not considered a single gene disease, the identified goals of gene therapy would be rather to provide neuroprotection of retinal ganglion cells, especially, in intraocular-pressure-independent manner. The most commonly reported type of vector for gene delivery in glaucoma studies is adeno-associated virus serotype 2 that has a high tropism to retinal ganglion cells, resulting in long-term expression and low immunogenic profile. The gene therapy studies recruit inducible and genetic animal models of optic neuropathy, like DBA/2J mice model of high-tension glaucoma and the optic nerve crush-model. Reported gene therapy-based neuroprotection of retinal ganglion cells is targeting specific genes translating to growth factors (i.e., brain derived neurotrophic factor, and its receptor TrkB), regulation of apoptosis and neurodegeneration (i.e., Bcl-xl, Xiap, FAS system, nicotinamide mononucleotide adenylyl transferase 2, Digit3 and Sarm1), immunomodulation (i.e., Crry, C3 complement), modulation of neuroinflammation (i.e., erythropoietin), reduction of excitotoxicity (i.e., CamKIIα) and transcription regulation (i.e., Max, Nrf2). On the other hand, some of gene therapy studies focus on lowering intraocular pressure, by impacting genes involved in both, decreasing aqueous humor production (i.e., aquaporin 1), and increasing outflow facility (i.e., COX2, prostaglandin F2α receptor, RhoA/RhoA kinase signaling pathway, MMP1, Myocilin). The goal of this review is to summarize the current state-of-art and the direction of development of gene therapy strategies for glaucomatous neuropathy.

Differential response of placental cells to high D‐glucose and its impact on extracellular vesicle biogenesis and trafficking via small GTPase Ras‐related protein RAB‐7A

AbstractPlacental extracellular vesicles (EVs) can be found in the maternal circulation throughout gestation, and their concentration, content and bioactivity are associated with pregnancy outcomes, including gestational diabetes mellitus (GDM). However, the effect of changes in the maternal microenvironment on the mechanisms associated with the secretion of EVs from placental cells remains to be fully established. Here, we evaluated the effect of high glucose on proteins associated with the trafficking and release of different populations of EVs from placental cells. BeWo and HTR8/SVneo cells were used as placental models and cultured under 5‐mM D‐glucose (i.e. control) or 25‐mM D‐glucose (high glucose). Cell‐conditioned media (CCM) and cell lysate were collected after 48 h. Different populations of EVs were isolated from CCM by ultracentrifugation (i.e. pellet 2K‐g, pellet 10K‐g, and pellet 100K‐g) and characterised by Nanoparticle Tracking Analysis. Quantitative proteomic analysis (IDA/SWATH) and multiple reaction monitoring protocols at high resolution (MRMHR) were developed to quantify 37 proteins related to biogenesis, trafficking/release and recognition/uptake of EVs. High glucose increased the secretion of total EVs across the pellets from BeWo cells, an effect driven mainly by changes in the small EVs concentration in the CCM. Interestingly, no effect of high glucose on HTR8/SVneo cells EVs secretion was observed. High glucose induces changes in proteins associated with vesicle trafficking in BeWo cells, including Heat Shock Protein Family A (Hsp70) Member 9 (HSPA9) and Member 8 (HSPA8). For HTR8/SVneo, altered proteins including prostaglandin F2α receptor regulatory protein (FPRP), RAB5A, RAB35, RAB5B, and RB11B, STAM1 and TSG101. These proteins are associated with the secretion and trafficking of EVs, which could explain in part, changes in the levels of circulating EVs in diabetic pregnancies. Further, we identified that proteins RAB11B, PDCD6IP, STAM, HSPA9, HSPA8, SDCBP, RAB5B, RAB5A, RAB7A and ERAP1 regulate EV release in response to high and low glucose when overexpressed in cells. Interestingly, immunohistochemistry analysis of RAB7A revealed distinct changes in placental tissues obtained from women with normal glucose tolerance (NGT, n = 6) and those with GDM (n = 6), influenced by diet or insulin treatment. High glucose regulation of proteins involved in intercellular dynamics and the trafficking of multivesicular bodies to the plasma membrane in placental cells is relevant in the context of GDM pregnancies.

Adverse events of topical ocular prostaglandin medications for glaucoma treatment: a pharmacovigilance study based on the FAERS database.

As prostaglandin medications, crucial in glaucoma treatment, become more widely used, their local adverse events are increasingly observed. To evaluate the common adverse events of four clinically commonly used prostaglandin F (FP) receptor agonists in the treatment of glaucoma in the Food and Drug Administration Adverse Event Reporting System (FAERS) database. We screened and analyzed the generic and brand names of latanoprost, bimatoprost, travoprost, and tafluprost in the FAERS database and summarized and cleaned the baseline information of subjects receiving the above-mentioned drugs. Perform descriptive statistical analysis on the baseline information of subjects using the drugs. Conduct disproportionality analysis of drug-related adverse events. The criteria for positive signals of adverse events are established by simultaneously meeting the thresholds set by four methods: the ratio of reported odds, proportional reporting ratio, Bayesian confidence propagation neural network, and multi-item gamma Poisson shrinker. Additionally, assess the cumulative risk curves for drug-induced time of the aforementioned drugs and use one-way ANOVA to compare differences in drug-induced time across different groups. The study included 1567 latanoprost, 1517 bimatoprost, 696 travoprost, and 82 tafluprost subjects. Adverse events mainly affected eye disorders, with significant issues in iris hyperpigmentation, ocular pemphigoid, corneal endothelial cell loss, periorbital fat atrophy, corneal irritation, eyelash growth, and ocular hyperemia. The time to onset varied among drugs, with latanoprost showing the longest (mean days = 344.37) and bimatoprost the shortest duration (mean days = 155.65; p < 0.001). Although signal detection analysis based on the FAERS database cannot establish a definitive causal relationship, our study found that FP receptor agonists used in glaucoma can cause various adverse events. Assessing their clinical suitability and potential side effects is crucial for providing personalized treatment and ensuring medication safety.

PGF2α induces a pro-labour phenotypical switch in human myometrial cells that can be inhibited with PGF2α receptor antagonists.

Preterm birth is the leading cause of infant morbidity and mortality. There has been an interest in developing prostaglandin F2α (PGF2α) antagonists as a new treatment for preterm birth, although much of the rationale for their use is based on studies in rodents where PGF2α initiates labour by regressing the corpus luteum and reducing systemic progesterone concentrations. How PGF2α antagonism would act in humans who do not have a fall in systemic progesterone remains unclear. One possibility, in addition to an acute stimulation of contractions, is a direct alteration of the myometrial smooth muscle cell state towards a pro-labour phenotype. In this study, we developed an immortalised myometrial cell line, MYLA, derived from myometrial tissue obtained from a pregnant, non-labouring patient, as well as a novel class of PGF2α receptor (FP) antagonist. We verified the functionality of the cell line by stimulation with PGF2α, resulting in Gαq-specific coupling and Ca2+ release, which were inhibited by FP antagonism. Compared to four published FP receptor antagonists, the novel FP antagonist N582707 was the most potent compound [Fmax 7.67 ± 0.63 (IC50 21.26nM), AUC 7.30 ± 0.32 (IC50 50.43nM), and frequency of Ca2+ oscillations 7.66 ± 0.41 (IC50 22.15nM)]. RNA-sequencing of the MYLA cell line at 1, 3, 6, 12, 24, and 48h post PGF2α treatment revealed a transforming phenotype from a fibroblastic to smooth muscle mRNA profile. PGF2α treatment increased the expression of MYLK, CALD1, and CNN1 as well as the pro-labour genes OXTR, IL6, and IL11, which were inhibited by FP antagonism. Concomitant with the inhibition of a smooth muscle, pro-labour transition, FP antagonism increased the expression of the fibroblast marker genes DCN, FBLN1, and PDGFRA. Our findings suggest that in addition to the well-described acute contractile effect, PGF2α transforms myometrial smooth muscle cells from a myofibroblast to a smooth muscle, pro-labour-like state and that the novel compound N582707 has the potential for prophylactic use in preterm labour management beyond its use as an acute tocolytic drug.

Structures of human prostaglandin F2α receptor reveal the mechanism of ligand and G protein selectivity

Prostaglandins and their receptors regulate various physiological processes. Carboprost, an analog of prostaglandin F2α and an agonist for the prostaglandin F2-alpha receptor (FP receptor), is clinically used to treat postpartum hemorrhage (PPH). However, off-target activation of closely related receptors such as the prostaglandin E receptor subtype EP3 (EP3 receptor) by carboprost results in side effects and limits the clinical application. Meanwhile, the FP receptor selective agonist latanoprost is not suitable to treat PPH due to its poor solubility and fast clearance. Here, we present two cryo-EM structures of the FP receptor bound to carboprost and latanoprost-FA (the free acid form of latanoprost) at 2.7 Å and 3.2 Å resolution, respectively. The structures reveal the molecular mechanism of FP receptor selectivity for both endogenous prostaglandins and clinical drugs, as well as the molecular mechanism of G protein coupling preference by the prostaglandin receptors. The structural information may guide the development of better prostaglandin drugs.

Pharmacotherapy of glaucoma in terms of evidence-based medicine

Glaucoma is a disease associated with increased intraocular pressure (IOP). Of the pharmacological agents for treating glaucoma, there are drugs of the first (most effective and safe) and second-line treatment. First-line treatment includes prostaglandin analogs and beta-blockers. The currently used prostaglandin analogs (latanoprost, bimatoprost, tafluprost and travoprost) are PG F2α analogs that act through stimulation of FP receptors. They are distinguished by the optimal ratio of effectiveness and risk of side effects. They are convenient for the patient because for the therapeutic effect, it is enough to prescribe 1 time per day. As a result, it is rational to start the treatment of glaucoma with a drug in this group. In terms of pharmacoeconomics, the most affordable prostaglandin drug is latanoprost, which is generally as effective as other prostaglandin analogs. β-adrenergic blockers reduce the production of intraocular fluid, the formation of which is controlled by β1- and β2-adrenergic receptors. Therefore, non-selective β-blockers (timolol, levobunolol, metipranolol, and carteolol) have a pharmacodynamic advantage over selective β1-adrenergic antagonists (betaxolol). Conducted clinical studies of β-blockers have shown that given the cost, efficacy and safety, timolol was the most preferable treatment for glaucoma. In the presence of medical contraindications to the use of first-line drugs or to enhance their effectiveness, α2-agonists (apraclonidine and brimonidine), carbonic anhydrase inhibitors (usually local action: dorzolamide and brinzolamide), M-cholinomimetics (pilocarpine, carbachol and echothiopate), and also Rho-kinase inhibitors (ripasudil)

Recovery from Upper Eyelid Sulcus Deepening Following Switch from Prostaglandin Analogues to EP2 Receptor Agonist

Purpose: To report a case of recovery from deepening of the upper eyelid sulcus after switching from prostaglandin FP receptor agonists to an EP2 receptor agonist.Case summary: A 65-year-old male patient with suspicion of glaucoma presented for detailed examinations. At the initial visit, his best-corrected visual acuity was 1.0 in both eyes, and the intraocular pressure (IOP) was 14/14 mmHg. Examination revealed no specific findings in the anterior segment, mild early cataracts bilaterally, and moderate glaucomatous changes. Therefore, bimatoprost/timolol fixed-combination eye drops were administered in both eyes. After 1 month, the IOP was 11/11 mmHg and no evidence of glaucoma progression was found. After 10 months, the IOP was 17/18 mmHg and there was deepening of the upper eyelid sulcus bilaterally. Consequently, bimatoprost/timolol fixed combination eye drops were switched to omidenepag isopropyl. Within 2 months of the switch, the deepening of the upper eyelid sulcus recovered completely and the IOP was 14/13 mmHg.Conclusions: Patients with prostaglandin-associated periorbitopathy should be switched to non-prostaglandin drugs or EP2 receptor agonists. Our patient exhibited complete recovery of the upper eyelid sulcus deepening after switching to an EP2 agonist.

Сучасні погляди на етіологію, патогенез і клінічний перебіг спонтанних передчасних пологів, тактику ведення та профілактику ускладнень (огляд літератури)

A review of medical literature regarding modern views on premature birth, the main issues of etiology and pathogenesis of this pathology, diagnostic signs, clinical features of the course, management tactics and perinatal consequences, investigated prognostic markers. A review of the medical literature regarding modern views on premature birth, the main issues of etiology and pathogenesis of this pathology, diagnostic signs, clinical features of the course, management tactics and perinatal consequences, investigated prognostic markers is provided. Despite the active and relentless development of medical science, the issue of premature births and their impact on short- and long-term consequences for mothers and children remains an urgent issue. Purpose - to highlight the scientists’ understanding of the etiology, pathogenesis, clinical management of premature birth, as well as to examine the available data on promising tocolytic drugs and methods of predicting premature birth. Among the tocolytic drugs currently undergoing clinical trials, the following groups are distinguished - broad-spectrum chemokine inhibitors, prostaglandin F2α-receptor target drugs, interleukin 1 receptor antagonists, and nanoparticle platforms. If the research is successful, obstetricians and gynecologists may have a targeted drug for the treatment of preterm labor with a better safety profile than the range of drugs we have today. Research into new laboratory prognostic markers of preterm birth, such as pregnancy-associated plasma protein A, human chorionic gonadotropin, alpha-fetoprotein, estriol, ferritin, ceruloplasmin, alkaline phosphatase, hematological markers, is also ongoing. The implementation of the above prognostic markers in clinical medicine will allow obtaining new opportunities in the early prediction of premature birth. Sonographic approaches to predicting premature birth are being updated. In addition to the measurement of the length of the cervix, the measurement of the uterine-cervical angle and the use of cervical elastography are used. Modern scientific achievements will allow doctors in the future at earlier stages of pregnancy to predict the possibility of premature birth and more effectively treat premature birth that has begun. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of the participating institution. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.

Prostaglandin F2α requires activation of calcium-dependent signalling to trigger inflammation in human myometrium.

Preterm birth is one of the major causes of neonatal morbidity and mortality across the world. Both term and preterm labour are preceded by inflammatory activation in uterine tissues. This includes increased leukocyte infiltration, and subsequent increase in chemokine and cytokine levels, activation of pro-inflammatory transcription factors as NF-κB and increased prostaglandin synthesis. Prostaglandin F2α (PGF2α) is one of the myometrial activators and stimulators. Here we investigated the role of PGF2α in pro-inflammatory signalling pathways in human myometrial cells isolated from term non-labouring uterine tissue. Primary myometrial cells were treated with G protein inhibitors, calcium chelators and/or PGF2α. Nuclear extracts were analysed by TranSignal cAMP/Calcium Protein/DNA Array. Whole cell protein lysates were analysed by Western blotting. mRNA levels of target genes were analysed by RT-PCR. The results show that PGF2α increases inflammation in myometrial cells through increased activation of NF-κB and MAP kinases and increased expression of COX-2. PGF2α was found to activate several calcium/cAMP-dependent transcription factors, such as CREB and C/EBP-β. mRNA levels of NF-κB-regulated cytokines and chemokines were also elevated with PGF2α stimulation. We have shown that the increase in PGF2α-mediated COX-2 expression in myometrial cells requires coupling of the FP receptor to both Gαq and Gαi proteins. Additionally, PGF2α-induced calcium response was also mediated through Gαq and Gαi coupling. In summary, our findings suggest that PGF2α-induced inflammation in myometrial cells involves activation of several transcription factors - NF-κB, MAP kinases, CREB and C/EBP-β. Our results indicate that the FP receptor signals via Gαq and Gαi coupling in myometrium. This work provides insight into PGF2α pro-inflammatory signalling in term myometrium prior to the onset of labour and suggests that PGF2α signalling pathways could be a potential target for management of preterm labour.

Prostanoid FP and EP2 Receptor Agonists Induce Epithelial and Subepithelial Fibrogenetic Changes in Human Conjunctival Fibroblasts in Different Manners.

Purpose: To examine the effects of prostanoid FP and EP2 receptor agonists, PGF2α and Omidenepag (OMD), respectively, on the transforming growth factor beta (TGF-β2) induced conjunctival fibrogenesis. Methods: Two-dimension (2D) and three-dimension (3D) cultures of these fibroblasts were subjected to following analyses: (1) planar proliferation evaluated by transendothelial electron resistance (TEER) measurements, (2) real-time metabolic analyses, (3) subepithelial proliferation evaluated by 3D spheroid' size and stiffness measurements, and (4) the mRNA expression of extracellular matrix (ECM) molecules and their modulators. Results: TGF-β2 induced increase in the planar proliferation was significantly decreased or enhanced by PGF2α or OMD, respectively. The proportion of oxygen consumption required to drive ATP synthesis compared with that driving proton leakage was increased by PGF2α and OMD independently with TGF-β2. In contrast, maximal mitochondrial respiration was decreased by PGF2α and OMD, and the OMD-induced effect was further enhanced by the presence of TGF-β2. In addition, the TGF-β2 dependent increase in the glycolytic capacity was cancelled by PGF2α and/or OMD. Alternatively, subepithelial proliferation, as evidenced by the stiffness of the 3D spheroids, was substantially increased by both PGF2α and OMD, and these were differently modulated by TGF-β2. The expression of several related factors as above fluctuated among the conditions for both 2D and 3D and TGF-β2 untreated or treated cultures. Conclusion: The present findings indicate that the prostanoid FP or the EP2 receptor agonist may solely and differently induce the planar and subepithelial proliferation of HconF cells and these were also modulated by TGF-β2.

Effect of cytobrush technique in mares

Several studies have been done correlating transcervical techniques or mechanical manipulation on the endometrium and its effect on the equine estrous cycle length in mares. However, the effect of the endometrial cytobrush technique on the estrous cycle and its use for the study of endometrial-ovarian relationships is still unknown. The aim of this study was to evaluate the usage of the endometrial cytobrush technique for study of the role of endometrial receptors and genes involved in the luteolytic mechanism. The study was divided in three groups: single endometrial cytobrush (CBS), endometrial samples collected in different animals on days 12, 14, and 16 (n = 5 /day); endometrial samples collect multiple times (CBM) in the same animal on days 12, 14, and 16 (n = 5/day); no endometrial samples collection (CSN). Blood samples were collected daily from ovulation to subsequent ovulation on the three groups to evaluate progesterone (P4) concentration. Additionally, on Day 12, blood samples were collected at h0 (just before cytobrush collection), 15 min, 30 min, h1, h2, and h4 to evaluate concentrations of P4 and a metabolite of prostaglandin F2α (PGFM). The gene expression was compared among the preluteolytic, luteolytic, and postluteolytic periods. The day before P4 concentration decreased by 20% from the previous day with an uninterrupteddecrease thereafter was defined as the beginning of luteolysis (luteolytic period), and the first day P4 concentration decreased to < 1.0 ng/mL was defined as the end of luteolysis (postluteolytic period). The interovulatory length, beginning of luteolysis, and concentrations of P4 and PGFM did not differ among the groups (P > 0.05). Three animals in the CBM group developed 5 ± 2 mm of endometrial fluid after the second cytobrush collection. However, these animals did not have endometrial fluid after ovulation. According to endometrial gene expression, in the CBM group, the prostaglandin-endoperoxide synthase 2 (PTGS2) was upregulated during luteolysis (P < 0.05), PGF transporter (SLCO2A1) was upregulated after luteolysis, and 15-hydroxyprostaglandin dehydrogenase (HPGD) was downregulated during luteolysis. In the CBS group, oxytocin receptor (OXTR), prostaglandin F2 receptor (PTGFS), and (HPGD) were upregulated during luteolysis (P < 0.05). SLCO2A1 was upregulated during and after luteolysis (P < 0.05). These results suggest that endometrial cytobrush technique does not influence the length of the cycle and is a viable method for studying endometrial gene expression of genes associated with luteolysis in a single sample collection in mares.