Prostaglandin Synthesis Research Articles

Temporal dissociation of COX-2-dependent arachidonic acid and 2-arachidonoylglycerol metabolism in RAW264.7 macrophages

Cyclooxygenase-2 converts arachidonic acid to prostaglandins (PGs) and the endocannabinoid, 2-arachidonoylglycerol (2-AG), to PG glyceryl esters (PG-Gs). The physiological function of PG biosynthesis has been extensively studied, but the importance of the more recently discovered PG-G synthetic pathway remains incompletely defined. This disparity is due in part to a lack of knowledge of the physiological conditions under which PG-G biosynthesis occurs. We have discovered that RAW264.7 macrophages stimulated with Kdo2-lipid A (KLA) produce primarily PGs within the first 12 h followed by robust PG-G synthesis between 12 h and 24 h. We suggest that the amount of PG-Gs quantified is less than actually synthesized, because PG-Gs are subject to a significant level of hydrolysis during the time course of synthesis. Inhibition of cytosolic phospholipase A2 by giripladib does not accelerate PG-G synthesis, suggesting the differential time course of PG and PG-G synthesis is not due to the competition between arachidonic acid and 2-AG. The late-phase PG-G formation is accompanied by an increase in the level of 2-AG and a concomitant decrease in 18:0-20:4 diacylglycerol (DAG). Inhibition of DAG lipases by KT-172 decreases the levels of 2-AG and PG-Gs, indicating that the DAG-lipase pathway is involved in delayed 2-AG metabolism/PG-G synthesis. These results demonstrate that physiologically significant levels of PG-Gs are produced by activated RAW264.7 macrophages well after the production of PGs plateaus.

Carnosine and Retinol Synergistically Inhibit UVB-Induced PGE2 Synthesis in Human Keratinocytes through the Up-Regulation of Hyaluronan Synthase 2.

Skin aging results from complex interactions of intrinsic and extrinsic factors, leading to structural and biochemical changes such as wrinkles and dryness. Ultraviolet (UV) irradiation leads to the degradation of hyaluronic acid (HA) in the skin, and the with fragmented HA contributes to inflammation. This study revealed that the synergistic combination of carnosine and retinol (ROL) increases HA production in normal human epidermal keratinocytes (NHEKs) by upregulating hyaluronan synthase 2 (HAS2) gene transcription. Simultaneously, the combined treatment of carnosine and ROL significantly attenuates UVB-induced prostaglandin E2 (PGE2) synthesis in NHEKs. A significant correlation exists between the increase of HA synthesis and the inhibition of PGE2 production. This study suggested that combined treatment of carnosine and ROL can improve skin aging phenotypes associated with UVB irradiation.

A fruit fly-based approach to unraveling enteropathy-causing pharmaceuticals.

Enteropathy is a gastrointestinal disorder characterized by inflammation in the small intestine and one of the causes of enteropathy is the side effects of certain drugs, such as non-steroidal anti-inflammatory drugs (NSAIDs). The mechanism of NSAIDs, such as indomethacin, could inhibit prostaglandin synthesis, leading to a decrease in mucus production and small intestine integrity. To test the effects of a drug, it is necessary to undergo preclinical testing using animal models. Commonly used animal models such as mice and rats have several drawbacks including high cost, ethical issues, and long lifespan. Therefore, alternatives such as using invertebrate animals like Drosophila melanogaster as a more economical in vivo platform with genetic similarity to mammals and devoid of ethical concerns are needed. The aim of this study was to evaluate Drosophila melanogaster as an in vivo model organism in testing the side effects of pharmaceuticals that cause enteropathy. In this study, flies aged 3-5 days were starved and then placed into treatment vials comprising untreated control and indomethacin-treated (3.75 mM, 7.5 mM, and 15 mM). Survival analysis was conducted during the treatment period, followed by a Smurf assay test after seven days of treatment. Subsequently, the expression of pro-inflammatory cytokine-related genes (drs and totA), mitochondria stability-related genes (tom40), and endogenous antioxidant-related genes (sod1, sod2, and cat) was performed using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Our data indicated that indomethacin did not impact lifespan or cause intestinal damage. However, we observed increased expression of pro-inflammatory cytokine-related genes, including drs, and a twofold increase in totA gene expression. Furthermore, there was a significant upregulation of mitochondrial stability gene tom40, endogenous antioxidant genes sod1 and cat, and a threefold increase in sod2 at 15 mM indomethacin. Although no phenotypical changes in gut integrity were detected, the increased expression of pro-inflammatory cytokine genes suggests the occurrence of inflammation in the indomethacin-treated flies.

Exploring the therapeutic targets of stevioside in management of type 2 diabetes by network pharmacology and in-silico approach

AimsThe main objective of the current study is to investigate the pathways and therapeutic targets linked to stevioside in the management of T2D using computational approaches. MethodsWe collected RNA-seq datasets from NCBI, then employed GREIN to retrieve differentially expressed genes (DEGs). Computer-assisted techniques DAVID, STRING and NetworkAnalyst were used to explore common significant pathways and therapeutic targets associated with T2D and stevioside. Molecular docking and dynamics simulations were conducted to validate the interaction between stevioside and therapeutic targets. ResultsGene ontology and KEGG analysis revealed that prostaglandin synthesis, IL-17 signaling, inflammatory response, and interleukin signaling were potential pathways targeted by stevioside in T2D. Protein-protein interactions (PPI) analysis identified six common hub proteins (PPARG, PTGS2, CXCL8, CCL2, PTPRC, and EDN1). Molecular docking results showed best binding of stevioside to PPARG (−8 kcal/mol) and PTGS2 (−10.1 kcal/mol). Finally, 100 ns molecular dynamics demonstrated that the binding stability between stevioside and target protein (PPARG and PTGS2) falls within the acceptable range. ConclusionsThis study reveals that stevioside exhibits significant potential in controlling T2D by targeting key pathways and stably binding to PPARG and PTGS2. Further research is necessary to confirm and expand upon these significant computational results.

Effect of central administration of indomethacin on anandamide-induced GnRH/LH secretion in the hypothalamus of anoestrous ewes.

It is suggested that cannabinoids (CBs) may disturb reproduction through action on hypothalamic gonadotropin-releasing hormone (GnRH) neurons directly or indirectly through intermediates such as prostaglandins. The study aimed to determine the influence of intracerebroventricular (i.c.v.) injection of the endogenous cannabinoid anandamide (N-arachidonoylethanolamine - AEA), alone or with the prostaglandin synthesis inhibitor indomethacin (IND), on GnRH/luteinising hormone (LH) secretion. The purpose of the research was to clarify the role of endocannabinoids and their interaction with prostaglandins in the regulation of reproduction at the level of the hypothalamus and pituitary in anoestrous sheep. The study was performed on 24 anoestrous ewes divided into four experimental groups: a control group receiving i.c.v. injection of Ringer-Locke solution, an AEA group that received i.c.v. injection of 30 μM of AEA, an IND group receiving i.c.v. injection of 5 μM of IND and an AEA + IND group that received i.c.v. injections of 30 μM of AEA and 5 μM of IND. Anandamide stimulated GnRH protein and gene expression in the median eminence and protein expression in the preoptic area without influencing GnRH messenger RNA (mRNA) in this structure. Indomethacin reversed the changes in GnRH secretion after AEA administration. It was also found that AEA stimulated LH mRNA in the pituitary without influencing LH release. Our results support the role of endogenous cannabinoids in the regulation of reproductive processes at the central nervous system level. They may act directly on the hypothalamic GnRH neurons or indirectly through intermediates such as prostaglandins.

The m6A eraser FTO suppresses ferroptosis via mediating ACSL4 in LPS-induced macrophage inflammation

Acute lung injury (ALI) is a serious disorder characterized by the release of pro-inflammatory cytokines and cascade activation of macrophages. Ferroptosis, a form of iron-dependent cell death triggered by intracellular phospholipid peroxidation, has been implicated as an internal mechanism underlying ALI. In this study, we investigated the effects of m6A demethylase fat mass and obesity-associated protein (FTO) on the inhibition of macrophage ferroptosis in ALI. Using a mouse model of lipopolysaccharide (LPS)-induced ALI, we observed the induction of ferroptosis and its co-localization with the macrophage marker F4/80, suggesting that ferroptosis might be induced in macrophages. Ferroptosis was promoted during LPS-induced inflammation in macrophages in vitro, and the inflammation was counteracted by the ferroptosis inhibitor ferrostatin-1 (fer-1). Given that FTO showed lower expression levels in the lung tissue of mice with ALI and inflammatory macrophages, we further dissected the regulatory capacity of FTO in ferroptosis. The results demonstrated that FTO alleviated macrophage inflammation by inhibiting ferroptosis. Mechanistically, FTO decreased the stability of ACSL4 mRNA via YTHDF1, subsequently inhibiting ferroptosis and inflammation by interrupting polyunsaturated fatty acid consumption. Moreover, FTO downregulated the synthesis and secretion of prostaglandin E2, thereby reducing ferroptosis and inflammation. In vivo, the FTO inhibitor FB23–2 aggravated lung injury, the inflammatory response, and ferroptosis in mice with ALI; however, fer-1 therapy mitigated these effects. Overall, our findings revealed that FTO may function as an inhibitor of the inflammatory response driven by ferroptosis, emphasizing its potential as a target for ALI treatment.

Design & Development Of Nano Formulations Of Various Anti Arthritic Agents For Arthritis.

Zaltoprofen and Cataflam are the NSAIDs category of drugs which could be used for the Arthritis for pain management. These are COX2 inhibitors, basically interfere with the prostaglandin synthesis and thus are able to reduce the sensation of pain in joints.

P-453 Non-autologous human platelet lysate as a therapy for recurrent implantation failure: lessons from in vitro models

Abstract Study question Which biological pathways are modulated by primary human endometrial cells in response to in vitro treatment with non-autologous human platelet lysate (HPL)? Summary answer HPL treatment stimulates endometrial growth and trophoblast attachment by activating cell proliferation, and modulating cell-cell signaling and extracellular matrix organization. What is known already Inadequate endometrial receptivity and a thin endometrium (TE) are contributing factors to recurrent implantation failure (RIF), which occurs in 10% of in vitro fertilization cycles. Studies have reported that autologous platelet-rich plasma stimulates endometrial growth and enhances receptivity, thereby improving implantation rate in RIF patients. We previously showed that non-autologous human platelet lysate (HPL) promotes in vitro proliferation of primary endometrial epithelial (EECs) and stromal cells (ESCs). Our data suggest that HPL may standardize and improve future clinical treatments for a TE and endometrial origins of RIF. Study design, size, duration Endometrial tissue was collected from five proliferative phase control and eighteen RIF patients at the CReATe Fertility Centre, Toronto, Canada. The RIF patients were separated into three groups (N = 6 each): 1) proliferative phase RIF, 2) secretory phase RIF, and 3) secretory phase RIF+TE. Primary EECs and ESCs were enzymatically isolated, cultured separately, and treated with either serum-free media (SFM), or SFM + 1% HPL (EECs), or 10% HPL (ESCs). Participants/materials, setting, methods Cell proliferation was assessed using PrestoBlueTM reagent and immunocytochemistry for Ki67. Pooled RNA libraries were prepared and sequenced for 150 cycles paired-end. Differential expression was performed using DESeq2 and pathway analysis with Enrichr. Using an in vitro model of embryo attachment, attachment between HTR-8/SVneo trophoblast spheroids and EECs was assessed by fluorescent microscopy and ImageJ™ software. Main results and the role of chance For all groups, 48-hour treatment with non-autologous HPL stimulates a significant increase (1.24-1.49-fold, P<0.05) in EEC proliferation. Whereas ESCs experienced a significant 1.29-fold and 1.92-fold increase (P<0.05) in proliferation for proliferative phase RIF and secretory phase RIF+TE respectively. HPL-treated EECs also exhibited significantly increased attachment to HTR-8 spheroids from 57.52% to 86.5% (P<0.01) in RIF+TE cultures and 42.58% to 68.90% (P<0.01) in RIF only cultures. Comparing SFM vs. HPL treatment identified 45 significantly upregulated (log2FoldChange >2 and padj <0.05) genes, including MMP1 and MMP9, and 30 significantly downregulated genes including KL and ADRA2A. Whereas ESCs had 429 significantly upregulated genes, including BUB1 and PLK1, and 378 significantly downregulated genes, including PTGIS and ADAMTS16. Upregulated pathways included extracellular matrix organization and mitotic cell cycle. Downregulated pathways included NOTCH1 signaling and synthesis of prostaglandins. Limitations, reasons for caution Our data suggests in vitro HPL treatment significantly stimulates endometrial cell proliferation, trophoblast attachment, and modulates receptivity. However, the small sample size per group (N = 6) underscores the need for larger samples and randomized controlled trials to establish the clinical efficacy of HPL as a treatment for endometrial origins of RIF. Wider implications of the findings HPL treatment for RIF and TE is gaining global acceptance by fertility clinics. Our study establishes the molecular groundwork to understand how HPL impacts endometrial growth and receptivity, offering mechanistic insights into this therapeutic approach and informing future treatments aimed at enhancing the success of embryo transfers. Trial registration number not applicable

Nonylphenol releases arachidonic acid in rat Sertoli cells via activation of PKA and PLA2.

The endocrine disruptor, nonylphenol (NP) increases 20:4n-6 release in Sertoli cells via PKA/cPLA2 activation. Our data show that lipid metabolism could be a target of NP-induced abnormal reproductive outcomes. Nonylphenol (NP), an endocrine-disrupting chemical, is an environmental contaminant, and many notorious effects on male fertility have been reported in animal models and wild-type species. Here, we evaluated the effects of NP in follicle-stimulating hormone (FSH) signal transduction pathways and lipid metabolism using an in vitro model of rat Sertoli cell (SC) primary culture. Results show that an acute (1 h) SC exposure to NP (10 µM) increased the intra- and extra-cellular concentrations of free fatty acids (FFAs), mainly arachidonic acid (20:4n-6). Phosphatidylinositol seemed to be the major phospholipid source of this 20:4n-6 release by activation of the protein kinase A (PKA)/cytoplasmic phospholipase A2 (cPLA2) pathway. NP also increased diacylglycerols (DAG) levels and the expression (mRNA) of cyclooxygenase 2 (Cox2) and prostaglandin E2 (PGE2) levels. It is noteworthy that accumulation of lipid droplets took place after 24 h NP exposition, which was prevented by both a PKA inhibitor and a PLA2 inhibitor. Like FSH, NP triggers the release of 20:4n-6, which is a substrate for PGE2 synthesis via PKA/PLA2 activation. In addition, NP induces the formation of DAG, which could be required as a cofactor of the PKC-mediated activation of the COX2 inflammatory pathway. Our findings suggest that NP alters lipid homeostasis in SCs by inducing the activation of pro-inflammatory pathways that may trigger adverse effects in testis physiology over time. Concomitantly, the SC enhances the acylation of surplus FFAs (including 20:4n-6) in neutral lipids as a protective mechanism to shield itself from lipotoxicity and pro-inflammatory signals.

Titanium nanotopography enhances mechano-response of osteocyte three-dimensional network toward osteoblast activation

The bone turnover capability influences the acquisition and maintenance of osseointegration. The architectures of osteocyte three-dimensional (3D) networks determine the direction and activity of bone turnover through osteocyte intercellular crosstalk, which exchanges prostaglandins through gap junctions in response to mechanical loading. Titanium nanosurfaces with anisotropically patterned dense nanospikes promote the development of osteocyte lacunar-canalicular networks. We investigated the effects of titanium nanosurfaces on intercellular network development and regulatory capabilities of bone turnover in osteocytes under cyclic compressive loading. MLO-Y4 mouse osteocyte-like cell lines embedded in type I collagen 3D gels on titanium nanosurfaces promoted the formation of intercellular networks and gap junctions even under static culture conditions, in contrast to the poor intercellular connectivity in machined titanium surfaces. The osteocyte 3D network on the titanium nanosurfaces further enhanced gap junction formation after additional culturing under cyclic compressive loading simulating masticatory loading, beyond the degree observed on machined titanium surfaces. A prostaglandin synthesis inhibitor cancelled the dual effects of titanium nanosurfaces and cyclic compressive loading on the upregulation of gap junction-related genes in the osteocyte 3D culture. Supernatants from osteocyte monolayer culture on titanium nanosurfaces promoted osteocyte maturation and intercellular connections with gap junctions. With cyclic loading, titanium nanosurfaces induced expression of the regulatory factors of bone turnover in osteocyte 3D cultures, toward higher osteoblast activation than that observed on machined surfaces. Titanium nanosurfaces with anisotropically patterned dense nanospikes promoted intercellular 3D network development and regulatory function toward osteoblast activation in osteocytes activated by cyclic compressive loading, through intercellular crosstalk by prostaglandin.

Significantly Positive Impact of Nonsteroidal Anti-inflammatory Drugs Combined With Osmoprotectant (Osmolytes) in Cancer Treatment.

Osmoprotectant osmolyteand nonsteroidal anti-inflammatory drug (NSAID) coadministration can work synergistically in cancer chemotherapy since most tumors are inflammatory and cancer cells experience osmotic stress. NSAIDs have been shown to inhibit cyclooxygenase (COX) enzymes, which in turn reduces prostaglandin synthesis and prevents inflammation. They also encourage cell death to prevent tumor growth and its spread to other tissues and prevent the construction of new blood vessels, which contributes to the growth of cancer. Taurine belongs to the class of osmolytes since it has been shown to stabilize macromolecular structures and maintain cellular osmotic balance when combined with betaine and glycine. When these drugs are taken together, as opposed to separately, the effectiveness of cancer treatment is increased by increasing cancer cell death and suppressing tumor growth. Notable therapeutic benefits include the reduction of local inflammatory milieu by NSAIDs, which promotes tumor development, and the protection of surviving, normal cells and tissues from treatment-induced damage caused by cancer. By enhancing this synergy, side-effect risk can be decreased and treatment outcomes improved in terms of quality. Put another way, peptides can increase the therapeutic index of NSAIDs in cancer patients by preventing cell damage, which may lessen the gastrointestinal (GI), cardiovascular (CV), and renal side effects of the drug. However, there are drawbacks because using NSAIDs for an extended period of time is linked to serious side effects that call for strict supervision. More research is required because the usefulness and significance of osmolytes in cancer therapy are still very unclear, if not fragmented. In addition, people who live in places with limited resources may find it difficult to afford the possible expenditures associated with osmolytes and selective cyclooxygenase-2 (COX-2) inhibitors. Only the molecular mechanisms of the two drugs' interactions, the appropriate dosages for combination therapy, and clinical trials to validate the efficacy and safety of this dosage should be the focus of future research. The request is inviting because it presents hope for an extremely successful antiviral strategy; nevertheless, in order to implement this approach successfully, it is likely to be necessary to create affordable formulations and scalable solutions that do not necessitate excessive treatment regimen individualization. Due to their complementary capacities to demonstrate anti-inflammatory and cytoprotective effects, Akta and5-aminosalicylic acid (5-ASA) administration may thus represent a significant advancement in the treatment of cancer.

From transcriptomics to digital twins of organ function.

Cell level functions underlie tissue and organ physiology. Gene expression patterns offer extensive views of the pathways and processes within and between cells. Single cell transcriptomics provides detailed information on gene expression within cells, cell types, subtypes and their relative proportions in organs. Functional pathways can be scalably connected to physiological functions at the cell and organ levels. Integrating experimentally obtained gene expression patterns with prior knowledge of pathway interactions enables identification of networks underlying whole cell functions such as growth, contractility, and secretion. These pathways can be computationally modeled using differential equations to simulate cell and organ physiological dynamics regulated by gene expression changes. Such computational systems can be thought of as parts of digital twins of organs. Digital twins, at the core, need computational models that represent in detail and simulate how dynamics of pathways and networks give rise to whole cell level physiological functions. Integration of transcriptomic responses and numerical simulations could simulate and predict whole cell functional outputs from transcriptomic data. We developed a computational pipeline that integrates gene expression timelines and systems of coupled differential equations to generate cell-type selective dynamical models. We tested our integrative algorithm on the eicosanoid biosynthesis network in macrophages. Converting transcriptomic changes to a dynamical model allowed us to predict dynamics of prostaglandin and thromboxane synthesis and secretion by macrophages that matched published lipidomics data obtained in the same experiments. Integration of cell-level system biology simulations with genomic and clinical data using a knowledge graph framework will allow us to create explicit predictive models that mechanistically link genomic determinants to organ function. Such integration requires a multi-domain ontological framework to connect genomic determinants to gene expression and cell pathways and functions to organ level phenotypes in healthy and diseased states. These integrated scalable models of tissues and organs as accurate digital twins predict health and disease states for precision medicine.

Oxylipins and metabolites from pyroptotic cells act as promoters of tissue repair.

Pyroptosis is a lytic cell death mode that helps limit the spread of infections and is also linked to pathology in sterile inflammatory diseases and autoimmune diseases1-4. During pyroptosis, inflammasome activation and the engagement of caspase-1 lead to cell death, along with the maturation and secretion of the inflammatory cytokine interleukin-1β (IL-1β). The dominant effect of IL-1β in promoting tissue inflammation has clouded the potential influence of other factors released from pyroptotic cells. Here, using a system in which macrophages are induced to undergo pyroptosis without IL-1β or IL-1α release (denoted Pyro-1), we identify unexpected beneficial effects of the Pyro-1 secretome. First, we noted that the Pyro-1 supernatants upregulated gene signatures linked to migration, cellular proliferation and wound healing. Consistent with this gene signature, Pyro-1 supernatants boosted migration of primary fibroblasts and macrophages, and promoted faster wound closure in vitro and improved tissue repair in vivo. In mechanistic studies, lipidomics and metabolomics of the Pyro-1 supernatants identified the presence of both oxylipins and metabolites, linking them to pro-wound-healing effects. Focusing specifically on the oxylipin prostaglandin E2 (PGE2), we find that its synthesis is induced de novo during pyroptosis, downstream of caspase-1 activation and cyclooxygenase-2 activity; further, PGE2 synthesis occurs late in pyroptosis, with its release dependent on gasdermin D pores opened during pyroptosis. As for the pyroptotic metabolites, they link to immune cell infiltration into the wounds, and polarization to CD301+ macrophages. Collectively, these data advance the concept that the pyroptotic secretome possesses oxylipins and metabolites with tissue repair properties that may be harnessed therapeutically.

Conceptus estrogen and prostaglandins provide the maternal recognition of pregnancy signal to prevent luteolysis during early pregnancy in the pig†.

Conceptus estrogens and prostaglandins have long been considered the primary signals for maternal recognition of pregnancy (MRP) in the pig. However, loss-of-function studies targeting conceptus aromatase genes (CYP19A1 and CYP19A2) and prostaglandin-endoperoxide synthase 2 (PTGS2) indicated that conceptuses can not only signal MRP without estrogens or prostaglandins but can maintain early pregnancy. However, complete loss of estrogen production leads to abortion after day 25 of gestation. Although neither conceptus estrogens nor prostaglandins had a significant effect on early maintenance of corpora lutea (CL) function alone, the two conceptus factors have a biological relationship. To investigate the role that both conceptus estrogens and prostaglandins have on MRP and maintenance of pregnancy, a triple loss-of function model (TKO) was generated for conceptus CYP19A1, CYP19A2, and PTGS2. In addition, a conceptus CYP19A2-/- model (A2KO) was established to determine the role of placental estrogen during later pregnancy. Estrogen and prostaglandin synthesis were greatly reduced in TKO concept uses which resulted in a failure to inhibit luteolysis after day 15 of pregnancy despite the presence of conceptuses in the uterine lumen. However, A2KO placentae not only maintained functional CL but were able to maintain pregnancy to day 32 of gestation. Despite the loss of placental CYP19A2 expression, the allantois fluid content of estrogen was not affected as the placenta compensated by expressing CYP19A1 and CYP19A3, which are normally absent in controls. Results suggest conceptuses can signal MRP through production of conceptus PGE or stimulating PGE synthesis from the endometrium through conceptus estrogen. Failure of conceptuses to produce both factors results in failure of MRP and loss of pregnancy.

НЕОБЫЧНЫЕ ПРЕВРАЩЕНИЯ АДДУКТА МИХАЭЛЯ ЛЕВОГЛЮКОЗЕНОНА И ЦИКЛОГЕКСАНОНА

Academician Genrikh Alexandrovich Tolstikov is a unique personality, a world-class scientist. During the years of his work as director of Institute of Organic Chemistry of the USC RAS (now the Ufa Institute of Chemistry of the Ufa Federal Research Center, Russian Academy of Sciences), new scientific directions were opened that are relevant and continue to this day. Research using sugars and anhydrous sugars, in particular, levoglucosane in the synthesis of prostaglandins and other bioactive structures, originates in the laboratory for the synthesis of low molecular weight bioregulators under the direction of prof. M.S. Miftakhov. After the creation of the laboratory for the synthesis of secondary metabolites (now the laboratory of pharmacophore cyclic systems) under the guidance of prof. Valeev F.A. Since the 90 s to the present, scientific research has been successfully conducted on the use of levoglucosenone and its derivatives in the synthesis of natural biologically active compounds and their analogues. Levoglucosenone attracted the attention of researches due to its availability and reactive, chiral structure. Its solubility in all organic solvents, and even in water, makes it a unique starting compound for organic synthesis. When describing the chemical behavior of levoglucosenone, it is important to note that many of its transformations proceed in a nontrivial manner and lead to unexpected products, which makes levoglucosenone an even more interesting object for study. Moreover, it turned out that the chemical transformations of its derivatives, in particular the Michael adducts of levoglucosenone and cycloalkanones, turned out to be even more unpredictable. This article is devoted to consideration of aspects of these transformations. Thus, it was found that two keto groups in the Michael adduct of levoglucosenone and cyclohexanone are not equivalent, the keto group of the carbohydrate fragment is more reactive. At the same time, when searching for the possibility of implementing intramolecular aldol condensation, it was unexpectedly found that the keto group of the carbohydrate fragment remains inert. Intramolecular carbocyclization could only be carried out in the Michael adduct of levoglucosenone and cyclododecanone. Based on the Michael adduct of levoglucosenone and cyclohexanone, a ten-membered lactone annelated with a carbohydrate fragment was synthesized. The problem of introducing substituents into the lactone cycle and modifying the carbohydrate part of the resulting lactone has been solved. On the basis of this adduct, an analog of the natural lactone, foracantholide, was synthesized. All results presented in the article include research conducted in our laboratory from 2014 to the present day.

The effect of selinexor on prostaglandin synthesis in virus-positive Merkel cell carcinoma cell lines.

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine skin cancer with high rates of metastasis and mortality. In vitro studies suggest that selinexor (KPT-330), an inhibitor of exportin 1, may be a targeted therapeutic option for MCC. This selective inhibitor prevents the transport of oncogenic mRNA out of the nucleus. Of note, 80% of MCC tumors are integrated with Merkel cell polyomavirus (MCPyV), and virally encoded tumor-antigens, small T (sT) and large T (LT) mRNAs may require an exportin transporter to relocate to the cytoplasm and modulate host tumor-suppressing pathways. To explore selinexor as a targeted therapy for MCC, we examine its ability to inhibit LT and sT antigen expression in vitro and its impact on the prostaglandin synthesis pathway. Protein expression was determined through immunoblotting and quantified by densitometric analysis. Statistical significance was determined with t-test. Treatment of MCPyV-infected cell lines with selinexor resulted in a significant dose-dependent downregulation of key mediators of the prostaglandin synthesis pathway. Given the role of prostaglandin synthesis pathway in MCC, our findings suggest that selinexor, alone or in combination with immunotherapy, could be a promising treatment for MCPyV-infected MCC patients who are resistant to chemotherapy and immunotherapy.

The importance of mechanosensitive cell mediated prostaglandin and nitric oxide synthesis in the pathogenesis of apical periodontitis: comparative with chronic periodontitis

ObjectivesMechano-sensitive odontoblast cells, which sense mechanical loading and various stresses in the tooth structure, synthesize early signaling molecules such as prostaglandin E2 (PGE2) and nitric oxide (NO) as an adaptive response. It is thought that these synthesized molecules can be used for the diagnosis and treatment of periodontal and periapical diseases. The aim of this study was to investigate the relationship between the severity of apical periodontitis (AP) and chronic periodontitis (CP) and serum (s) TNF-α, IL-10, PGE2 and NO levels, as well as PGE2 and NO levels in gingival crevicular fluid (GCF) samples.Materials & methodsA total of 185 subjects were divided into three categories: AP group (n = 85), CP group (n = 50) and healthy control group (n = 50). The AP group was divided into 3 subgroups according to abscess scoring (AS-PAI 1, 2 and 3) based on the periapical index. The CP group was divided into 4 subgroups according to the periodontitis staging system (PSS1, 2,3 and 4). After recording the demographic and clinical characteristics of all participants, serum (s) and gingival crevicular fluid (GCF) samples were taken. TNF-α, IL-10, PGE2 and NO levels were measured in these samples.ResultsUnlike serum measurements (sTNF-α, sIL-10, sNO and sPGE2), GCF-NO and GCF-PGE levels of the AP group were significantly higher than the control group in relation to abscess formation (54.4 ± 56.3 vs. 22.5 ± 12.6 µmol/mL, p < 0.001 and 100 ± 98 vs. 41 ± 28 ng/L, p < 0.001, respectively). Confirming this, the GCF-NO and GCF-PGE levels of the AS-PAI 1 group, in which abscesses have not yet formed, were found to be lower than those in AS-PAI 2 and 3, which are characterized by abscess formation [(16.7(3.7-117.8), 32.9(11.8-212.8) and 36.9(4.3-251.6) µmol/mL, p = 0,0131; 46.0(31.4–120.0), 69.6(40.3-424.2) and 74.4(32.1–471.0) ng/L, p = 0,0020, respectively]. Consistent with the increase in PSS, the levels of sTNF [29.8 (8.2-105.5) vs. 16.7(6.3–37.9) pg/mL, p < 0.001], sIL-10 [542(106–1326) vs. 190(69–411) pg/mL, p < 0.001], sNO [182.1(36.3–437) vs. 57.0(15.9–196) µmol/mL, p < 0.001], sPGE2 [344(82-1298) vs. 100(35-1178) ng/L, p < 0.001], GCF-NO [58.9 ± 33.6 vs. 22.5 ± 12.6 ng/L, p < 0.001] and GCF-PGE2 [ 99(37–365) vs. 30(13–119), p < 0.001] in the CP group were higher than the control group. Comparison ROC analysis revealed that the GCF-PGE2 test had the best diagnostic value for both AP and CP (sensitivity: 94.1 and 88.0; specificity: 64.0 and 78.0, respectively; p < 0.001).ConclusionsGCF-PE2 and GCF-NO have high diagnostic value in the determination of AP and CP, and can be selected as targets to guide treatment. In addition, the measurements of PGE2 and NO in GCF can be used as an important predictor of pulpal necrosis leading to abscess in patients with AP.Clinical relevanceIn this article, it is reported that syntheses of early signaling molecules such as PGE2 and NO can be used for the diagnosis and treatment target of periapical and periodontal infections.

Inflammatory bowel diseases and modern methods of their treatment

Chronic inflammatory bowel diseases are a group of diseases that still do not have a specific cause of their occurrence, are characterized by a particularly complex pathogenesis, a variety of clinical manifestations and a significant impact on the patient’s quality of life. Crohn’s disease and non-specific ulcerative colitis are diseases that run with the risk of severe exacerbations and can also lead to the patient’s disability. The main task in the treatment of inflammatory bowel diseases is the initiation of the remission stage and its long-term maintenance. For this, several groups of drugs are used, among which the drug of the first line of therapy is Mesalazine (Mesacol®), its effect on the intestinal wall consists in preventing the development of the inflammatory process by reducing the synthesis of pro-inflammatory prostaglandins and leukotrienes, slowing down the migration, degranulation and phagocytosis of neutrophils. In addition, mesalazine neutralizes free radicals, which increases the protective effect on the intestinal wall.

Post-resolution macrophages shape long-term tissue immunity and integrity in a mouse model of pneumococcal pneumonia

Resolving inflammation is thought to return the affected tissue back to homoeostasis but recent evidence supports a non-linear model of resolution involving a phase of prolonged immune activity. Here we show that within days following resolution of Streptococcus pneumoniae-triggered lung inflammation, there is an influx of antigen specific lymphocytes with a memory and tissue-resident phenotype as well as macrophages bearing alveolar or interstitial phenotype. The transcriptome of these macrophages shows enrichment of genes associated with prostaglandin biosynthesis and genes that drive T cell chemotaxis and differentiation. Therapeutic depletion of post-resolution macrophages, inhibition of prostaglandin E2 (PGE2) synthesis or treatment with an EP4 antagonist, MF498, reduce numbers of lung CD4+/CD44+/CD62L+ and CD4+/CD44+/CD62L-/CD27+ T cells as well as their expression of the α-integrin, CD103. The T cells fail to reappear and reactivate upon secondary challenge for up to six weeks following primary infection. Concomitantly, EP4 antagonism through MF498 causes accumulation of lung macrophages and marked tissue fibrosis. Our study thus shows that PGE2 signalling, predominantly via EP4, plays an important role during the second wave of immune activity following resolution of inflammation. This secondary immune activation drives local tissue-resident T cell development while limiting tissue injury

Furosemide and Ductus Arteriosus Closure in Very-Low-Birth-Weight Preterm Infants: A Comprehensive Retrospective Study.

Ductus arteriosus closure may be delayed in preterm infants, and prostaglandin, a vasodilator, can affect ductal patency. Furosemide can increase renal prostaglandin synthesis, so its net effect on patent ductus arteriosus (PDA) is uncertain. Our goal is to explore the relationship between furosemide and spontaneous ductal closure in very-low-birth-weight preterm infants. Our treatment for PDA involves fluid restriction initially and furosemide administration for hemodynamically significant PDA until closure is confirmed by the echocardiogram. We enrolled 105 infants from 1 January 2019 to 30 June 2022 and evaluated the impact of furosemide on ductal closure, including exposure duration and cumulative dose. There is no correlation between furosemide exposure and spontaneous ductal closure (p = 0.384). Furosemide exposure does not delay the postmenstrual age at which spontaneous ductal closure occurs (p = 0.558). The time for spontaneous ductal closure is positively associated with furosemide prescription days (coefficient value = 0.547, p = 0.026) and negatively with gestational age (coefficient value = -0.384, p = 0.062). The prescription of furosemide does not impact the probability or time duration of ductus arteriosus spontaneous closure. The cumulative dose of furosemide has minimal impact on ductal closure. The correlation between furosemide exposure duration and ductal patency duration is likely due to our treatment protocol, with gestational age being a significant factor.