Prostaglandin-endoperoxide Synthase 2 Expression Research Articles

Endothelial ROBO4 suppresses PTGS2/COX-2 expression and inflammatory diseases

Accumulating evidence suggests that endothelial cells can be useful therapeutic targets. One of the potential targets is an endothelial cell-specific protein, Roundabout4 (ROBO4). ROBO4 has been shown to ameliorate multiple diseases in mice, including infectious diseases and sepsis. However, its mechanisms are not fully understood. In this study, using RNA-seq analysis, we found that ROBO4 downregulates prostaglandin-endoperoxide synthase 2 (PTGS2), which encodes cyclooxygenase-2. Mechanistic analysis reveals that ROBO4 interacts with IQ motif-containing GTPase-activating protein 1 (IQGAP1) and TNF receptor-associated factor 7 (TRAF7), a ubiquitin E3 ligase. In this complex, ROBO4 enhances IQGAP1 ubiquitination through TRAF7, inhibits prolonged RAC1 activation, and decreases PTGS2 expression in inflammatory endothelial cells. In addition, Robo4-deficiency in mice exacerbates PTGS2-associated inflammatory diseases, including arthritis, edema, and pain. Thus, we reveal the molecular mechanism by which ROBO4 suppresses the inflammatory response and vascular hyperpermeability, highlighting its potential as a promising therapeutic target for inflammatory diseases.

Integration of single-cell RNA sequencing of endothelial cells and proteomics to unravel the role of ICAM1-PTGS2 communication in apical periodontitis: A laboratory investigation.

Endothelial cells (EDs) play a key role in angiogenesis and are associated with granulomatous lesions in patients with chronic apical periodontitis (CAP). This study aimed to investigate the diversity of EDs using single-cell ribonucleic acid sequencing (scRNA-seq) and to evaluate the regulation of intercellular adhesion molecule 1 (ICAM1) on the ferroptosis-related protein, prostaglandin-endoperoxide synthase 2 (PTGS2), in CAP. EDs from the uploaded scRNA-seq data of five CAP samples (GSE181688 and GSE197680) were categorized using distinct marker genes. The interactions between vein EDs (veinEndo) and other cell types were analysed using CellPhoneDB. Differentially expressed proteins in the proteomics of human umbilical vein EDs (HUVECs) and THP-1-derived macrophages infected with Porphyromonas gingivalis were compared with the differentially expressed genes (DEGs) of VeinEndo in scRNA-seq of CAP versus healthy control periodontal tissues. The protein-protein interaction of ICAM1-PTGS2 in macrophages and HUVECs was validated by adding recombinant ICAM1, ICAM1 inhibitor and PTGS2 inhibitor using real-time polymerase chain reaction (PCR), western blotting, and immunofluorescence staining. EDs in patients with CAP were divided into eight subclusters: five vein ED, capillaries, arterials and EC (PLA). There were 29 mutually upregulated DEGs and two mutually downregulated DEGs in vein cells in the scRNA-seq data, as well as differentially expressed proteins in the proteomics of HUVECs. Real-time PCR and immunofluorescence staining showed that ICAM1 and PTGS2 were highly expressed in CAP, infected HUVECs, and macrophages. Recombinant protein ICAM1 may improve PTGS2 expression, reactive oxygen species (ROS), and Fe2+ levels and decrease glutathione peroxidase 4 (GPX4) and SLC7A11 protein levels. ICAM1 inhibitor may inverse the above changes. scRNA-seq revealed the diversity of EDs in CAP and identified the possible regulation of ICAM1 by the ferroptosis-related protein, PTGS2, in infected HUVECs and macrophages, thus providing a basis for therapeutic approaches that target the inflammatory microenvironment of CAP.

Hypoglycemic TCM formulas (Huangqi-Gegen drug pair) have the potential as an Alzheimer's disease

BackgroundAlzheimer's disease (AD) is a neurological disorder. There is a considerable unmet medical need among those suffering from it. Hypothesis and purposeGiven the link between type-2 diabetes mellitus (T2DM) and AD, hypoglycemic traditional Chinese medicine formulas (TCMFs) may be a treatment for AD. We investigated the possibility of identifying anti-AD medicines in hypoglycemic TCMFs and presented another option for the screening of AD medications. Study design and methodsParalysis of the transgenic Caenorhabditis elegans (C. elegans) strain CL4176 (caused by amyloid beta (Aβ)1–42 aggregates) was used to evaluate the anti-AD effect. The toxicity and neurodegeneration induced by neuronal expression of Aβ in the transgenic C. elegans strain CL2355 were determined using a 5-hydroxytryptamine (5-HT) assay. The transgenic Aβ-expressing strain CL 2006 and transgenic tau-expressing strain BR5270 were used to explore the effect of TCMFs on protein expression in C. elegans using ELISAs. Then, network pharmacology was used to determine the mechanism of action. The Traditional Chinese Medicine Inheritance Support System platform was used to investigate prescription patterns, core drugs, and optimum combinations of hypoglycemic TCMFs for AD. ResultsSixteen hypoglycemic TCMFs prolonged the PT50 (half paralysis time) of the CL4176 strain of C. elegans, reduced the percentage of worms paralyzed. The results of network pharmacology showed that prostaglandin-endoperoxide synthase 2 (PTGS2) and acetylcholine esterase (AChE) are main targets of hypoglycemic TCMFs. Enriched pathway analysis showed that the cholinergic receptor-related pathway was the core pathway of hypoglycemic TCMFs. According to the “four qi and five flavors” system of TCM theory, the main pharmacological qualities were “cold” and “sweet.” Through the analysis by TCMISS, we found that Huangqi-Gegen drug pair as the significant Chinese herbs of hypoglycemic TCMFs. The Huangqi–Gegen pairing had the most robust therapeutic effect when delivered at a 2:1 (v/v) ratio. It reduced the paralysis caused by 5-HT, decreased protein expression of AChE and PTGS2, and reduced Aβ deposition in the brain of the CL2006 strain of C. elegans. ConclusionsHuangqi–Gegen is a promising treatment of AD, and its mechanism may be induced by suppressing the protein production of AChE and PTGS2, reducing 5-HT intake, and then decreasing Aβ deposition.

Protective mechanism of Paeoniae Radix Alba against chemical liver injury based on network pharmacology, molecular docking, and in vitro experiments

ObjectiveTo explore and validate the potential targets of Paeoniae Radix Alba (P. Radix, Bai Shao) in protecting against chemical liver injury through network pharmacology, molecular docking technology, and in vitro cell experiments. MethodsNetwork pharmacology was used to identify the common potential targets of P. Radix and chemical liver injury. Molecular docking was used to fit the components, which were subsequently verified in vitro. A cell model of hepatic fibrosis was established by activating hepatic stellate cell (HSC)-LX2 cells with 10 ng/mL transforming growth factor-β1. The cells were exposed to different concentrations of total glucosides of paeony (TGP), the active substance of P. Radix, and then evaluated using the cell counting kit-8 assay, enzyme-linked immunosorbent assay, and western blot. ResultsAnalysis through network pharmacology revealed 13 key compounds of P. Radix, and the potential targets for preventing chemical liver injury were IL-6, AKT serine/threonine kinase 1, jun proto-oncogene, heat shock protein 90 alpha family class A member 1 (HSP90AA1), peroxisome proliferator activated receptor gamma (PPARG), PTGS2, and CASP3. Gene Ontology (GO) enrichment analysis indicated the involvement of response to drugs, membrane rafts, and peptide binding. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that the main pathways involved lipid and atherosclerosis and chemical carcinogenesis-receptor activation. Paeoniflorin and albiflorin exhibited strong affinity for HSP90AA1, PTGS2, PPARG, and CASP3. Different concentrations of TGP can inhibit the expression of COL-Ⅰ, COL-Ⅲ, IL-6, TNF-α, IL-1β, HSP-90α, and PTGS2 while increasing the expression of PPAR-γ and CASP3 in activated HSC-LX2 cells. ConclusionP. Radix primarily can regulate targets such as HSP90AA1, PTGS2, PPARG, CASP3. TGP, the main active compound of P. Radix, protects against chemical liver injury by reducing the inflammatory response, activating apoptotic proteins, and promoting the apoptosis of activated HSCs.

Echinacoside ameliorates doxorubicin‑induced cardiac injury by regulating GPX4 inhibition‑induced ferroptosis.

Echinacoside (ECH) is a compound derived from the natural herbs Cistanche and Echinacea, which has considerable protective effects on heart failure (HF). HF is characterized by myocardial damage and abnormal ferroptosis. Glutathione peroxidase 4 (GPX4) is an important regulator of ferroptosis, which plays a role in ferroptosis-related diseases. Despite this, the therapeutic mechanisms of ECH against HF remain unknown. Therefore, the aim of the present study was to investigate the cardioprotective effect and underlying mechanisms of ECH in the treatment of doxorubicin (DOX)-induced chronic HF (CHF). Cell proliferation was assessed using a CCK-8 assay. Furthermore, cardiac cell injury and oxidative stress were determined by measuring the lactate dehydrogenase (LDH), malondialdehyde (MDA), and glutathione (GSH) levels. The levels of Fe2+ and lipid reactive oxygen species (ROS), and expression of the biomarkers of ferroptosis, including GPX4 and prostaglandin-endoperoxide synthase 2 (PTGS2), were measured to examine cardiomyocyte ferroptosis. Additionally, RNA interference was used to silence Gpx4. In vitro and in vivo, ECH considerably reduced the MDA and LDH levels and increased the GSH level, thereby attenuating DOX-induced cardiac injury and oxidative stress. Meanwhile, ECH treatment decreased the lipid ROS levels and PTGS2 expression while increasing GPX4 expression, thereby alleviating DOX-induced cardiomyocyte ferroptosis. Moreover, knockdown of Gpx4 inhibited the protective effects of ECH on DOX-induced accumulation of lipid ROS in cardiomyocytes. These findings indicate that ECH can reduce DOX-induced cardiac injury by inhibiting ferroptosis via GPX4, highlighting its value as a potentially valuable therapeutic target in the management of CHF.

Network pharmacology and experimental validation methods to reveal the active compounds and hub targets of Curculigo orchioides Gaertn in rheumatoid arthritis

BackgroundRheumatoid arthritis (RA) is an autoimmune disease that can lead to joint destruction and deformity. Curculigo orchioides Gaertn (CO) was previously revealed to play a significant role in RA treatment. However, the main active ingredients and molecular mechanisms of CO in regulating RA are still unclear.MethodsThe active ingredients of CO were obtained from the Traditional Chinese Medicine Systems Pharmacology database and published literature. The targets corresponding to these compounds and the targets linked to RA were collected from public databases. The “ingredient-target” and “protein–protein interaction” networks were constructed to screen the main active ingredients and hub targets of CO in the treatment of RA. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment assays were used to elucidate the potential pharmacological mechanism of CO in RA. Molecular docking was performed to detect the binding between the main active ingredients and hub targets. Collagen-induced arthritis rats were used to validate the hub targets of CO against RA.ResultsNetwork pharmacological topology analysis showed that caffeine, 2,4-dichloro-5-methoxy-3-methylphenol, curculigoside, orcinol glucoside, and orcin were the main active ingredients of CO, and matrix metalloproteinase 9 (MMP9), transcription factor AP-1 (JUN), prostaglandin-endoperoxide synthase 2 (PTGS2), brain-derived neurotrophic factor, and receptor-type tyrosine-protein phosphatase C were the hub targets of CO for RA treatment. Molecular docking revealed that curculigoside and orcinol glucoside had effective binding potential with MMP9, JUN, and PTGS2, respectively. In vivo experiments demonstrated that CO alleviated RA symptoms and inhibited the expression of MMP9, JUN, and PTGS2 proteins.ConclusionsOur study demonstrates the main active ingredients and potential targets of CO against RA, laying an experimental foundation for the development and application of CO as an anti-RA drug.

TMIC-72. INVESTIGATING THE ROLES OF PGE2 IN MODULATING THE GBM-GAM MICROENVIRONMENT

Abstract Glioblastoma (GBM), the most aggressive and deadliest primary brain tumor, is characterized by being surrounded by up to approximately 40% macrophages, which promote tumor progression through interactions with tumor cells. The mechanisms underlying how GBM and its associated macrophages (GAM) communicate remain not fully understood. In this study, we investigated the essential roles of Prostaglandin E2 (PGE2), which affects multiple functions of immune cells, in modulating the GBM microenvironment, specifically the GAM. Massive PGE2 accumulated in the GBM-GAM co-culture microenvironment, and the expression of prostaglandin-endoperoxide synthase 2 (PTGS2) involved in PGE2 synthesis was markedly elevated in GAM. GAM expressed two PGE2 receptors, namely EP2 and EP4, and their expressions positively correlated with PTGS2 expression. Ingenuity pathway analysis (IPA) of differentially expressed (DE) genes obtained from GBM- (conditioned medium) CM-treated THP-1 macrophages revealed significant enrichment in biological functions associated with migration and proliferation. THP-1 macrophage migration promoted by GBM-CM was interrupted by blocking EP4 receptors using an antagonist. GBM-CM promoted THP-1 macrophages proliferation and increased proliferative enhancers, such as PI3KCD, AKT3, ETS1, and BHLHE41, while decreasing proliferative repressors, including MAF, MAFB, and CDKN1A. Cytokine array analysis indicated that GBM-CM shaped GAM into an immunosuppressive phenotype and elevated IL-6 secretion to promote GBM growth. In conclusion, our current results suggest that PGE2 accumulates in the GBM microenvironment, sustaining the macrophage population through increased recruitment and elevated local proliferation and shaping macrophages into an immunosuppressive type. Blockage of the PGE2 autocrine regulation, thus interrupting the supportive roles of GAM in GBM progression, may provide a novel therapeutic strategy for treating patients with GBM.

Integration of metabolomics and network pharmacology to reveal the protective mechanism underlying Qibai Pingfei capsule on chronic obstructive pulmonary disease.

In this study, we have employed metabolomics technology in combination with network pharmacology to ascertain the key metabolites and hub genes. The objective was to explore the pathway of Qibai Pingfei Capsule (QBPF) in treating COPD through metabolomics. We identified 96 differential metabolites in the lung tissues of rats belonging to control and model groups, out of which 47 were observed to be critical (VIP >2, p < 0.05). Furthermore, 16 important differential metabolites were reversed after QBPF treatment. Using network pharmacology, we identified 176 core targets of 81 drug-active ingredients. Our comprehensive analysis of network pharmacology and metabolomics enabled us to identify a core target, prostaglandin-endoperoxide synthase 2 (PTGS2), and a core metabolic pathway for glutathione metabolism. Finally, the result of molecular docking showed that PTGS2 had strong binding activity to 18 compounds including Fumarine and Kaempferol, etc.. PTGS2 is a marker of ferroptosis, so we wanted to explore whether QBPF could inhibit ferroptosis in COPD. The results showed that ferroptosis was involved in the pathogenesis of COPD, and QBPF could inhibit the occurrence of ferroptosis. In conclusion, the mechanism of QBPF for treating COPD may be related to PTGS2 expression, glutathione metabolism and ferroptosis.

Prostaglandin-endoperoxide synthase 2 (PTGS2) gene expression and its association with genes regulating the VEGF signaling pathway in head and neck squamous cell carcinoma

The PTGS2 gene codes for the cyclooxygenase-2 (COX-2) enzyme that catalyzes the committed step in prostaglandin (PG) synthesis. Various in-vivo and in-vitro data suggest that prostaglandin E2 mediates as a signaling molecule for activating the VEGF signaling pathway (VSP), forming an association between COX-2 and VSP. Several chemotherapy regimens increasingly rely on preventing the synthesis of PGs. The targeted and metronomic chemotherapy agents, which suppress the COX-2 enzymes, have a major role in suppressing the oral cancer cascade. Hence, this study was designed to understand the pattern of PTGS2 expression and genes regulating VSP in head and neck cancers. PTGS2 expression was analyzed in the TCGA database computationally with the help of the UALCAN web-server. The expression of VEGF signaling pathway genes was mined, and their expression pattern was determined. Co-expression analysis was done to elucidate the association between VEGF signaling genes and PTGS2. The ShineyGo web server was used for gene set enrichment. Significantly high PTGS2 expression was observed in tumor samples. Further genes regulating VEGF signaling were significantly overexpressed in tumor samples. Co-expression analysis results showed a significant positive correlation between PTGS2 and angiogenesis-regulating genes. The majority of the genes were enriched for angiogenesis pathways. PTGS2 was significantly expressed in head and neck cancer, and its expression was associated with genes regulating angiogenesis.

SNORA71C promotes development and metastasis of breast cancer by regulating RUNX1 and ferroptosis.

SNORA71C promotes development and metastasis of breast cancer by regulating RUNX1 and ferroptosis.

Sinomenine alleviates diabetic peripheral neuropathic pain through inhibition of the inositol-requiring enzyme 1 alpha-X-box binding protein 1 pathway by downregulating prostaglandin-endoperoxide synthase 2.

We tried to show the effect of sinomenine (SIN) in diabetic peripheral neuropathic pain (DPNP) and the related underlying mechanism. Network pharmacological analysis and bioinformatics analysis were carried out for identification of the active ingredients of Sinomenium acutum and the related genes. The DPNP rat model was constructed and primary rat spinal cord microglial cells were isolated for in vitro cell experiments. The therapeutic role of SIN in DPNP was determined in vivo and in vitro through analysis of microglial cell activation and inflammatory response. Therapeutic role of S.acutum in DPNP was mainly achieved by regulating 14 key genes, among which the target gene prostaglandin-endoperoxide synthase 2 (PTGS2) of SIN might be the key gene. An in vivo experiment showed that SIN inactivated the inositol-requiring enzyme 1 alpha-X-box binding protein 1 pathway by downregulating PTGS2, which relieved pain symptoms in DPNP rats. It was confirmed in vivo that SIN inhibited the pathway through PTGS2 to alleviate the activation of spinal cord microglial cells and inflammatory response. SIN decreases the expression of PTGS2 to inactivate the inositol-requiring enzyme 1 alpha-X-box binding protein 1 signaling pathway, which inhibits microglial activation, as well as the release of inflammatory factors, thus alleviating DPNP.

LPS-induced PTGS2 manipulates the inflammatory response through trophoblast invasion in preeclampsia via NF-κB pathway.

Preeclampsia (PE) is a serious obstetric complication, in which trophoblast cell invasion and migration contribute to placental inflammation. In line with the discovery that mRNA prostaglandin endoperoxide synthase 2 (PTGS2) participates in the inflammatory responses in various disorders, our study aims to explore the role of PTGS2 in trophoblast invasion and further in inflammatory response in PE, ultimately providing new therapeutic targets. Bioinformatics analysis was exploited to examine PTGS2 expression in GSE40182 and find inflammatory response-relevant genes in downstream targets of PTGS2. HTR-8/SVneo cells were treated with lipopolysaccharide (LPS) and transfected with short hairpin RNA against PTGS2 (shPTGS2). Quantitative real-time polymerase chain reaction (qRT-PCR), Western blotting, and immunofluorence assays were performed to quantify the expressions of PTGS2 and involved genes (matrix metallopeptidase 2 (MMP-2), tissue inhibitors of metalloproteinase-2 (TIMP-2), p65, p-p65, IκB-α, p-IκB-α, PTGIS, CAV1, AGTR1). The migration and invasion of trophoblasts were detected through wound healing and Transwell assays. We screened out PTGS2 from GSE40182 dataset. LPS promoted cell migration and invasion, the expressions of PTGS2 and MMP-2, and reduced the expression of TIMP-2, while PTGS2 knockdown reversed all above effects of LPS. Activation of nuclear factor kappa-B (NF-κB) pathway was reinforced by LPS which also upregulated CAV1 and AGTR1 levels, and downregulated PTGIS level. Also, the effects of LPS were offset by PTGS2 knockdown. Altogether, PTGS2 silencing reverses the promoting effect of LPS on trophoblast invasion and inflammation in PE, making a breakthrough in the research regarding molecular mechanism of PE.

Exploring the Molecular Mechanism of Tong Xie Yao Fang in Treating Ulcerative Colitis Using Network Pharmacology and Molecular Docking.

Objective The purpose of this study was to investigate the mechanisms of action of Tong Xie Yao Fang (TXYF) against ulcerative colitis (UC) by employing a network pharmacology approach. Methods The network pharmacology approach, including screening of the active ingredients and targets, construction of the active ingredient-drug target network, the active ingredient-diseasetarget network, the protein–protein interaction (PPI) network, enrichment analyses, molecular docking, and targets validation, was used to explore the mechanisms of TXYF against UC. Results 34 active ingredients and 129 and 772 targets of TXYF and UC, respectively, were identified. The intersection of the active ingredient-drug target network, the active ingredient-disease target network, and the PPI network suggested that kaempferol, beta-sitosterol, wogonin, and naringenin were the core ingredients and prostaglandin-endoperoxide synthase 2 (PTGS2) was the core target. Enrichment analyses showed that regulation of exogenous protein binding and other functions were of great significance. Nuclear factor-kappa B (NF-κB) signaling pathway, interleukin-17 (IL-17) signaling pathway, and tumor necrosis factor (TNF) signaling pathway were important pathways. Results of molecular docking indicated that the core ingredients and the target molecule had strong binding affinities. We have validated the high levels of expression of PTGS2 in UC by analyzing three additional datasets from the Gene Expression Omnibus (GEO) database. Conclusions There are multiple ingredients, targets, and pathways involved in TXYF's effectiveness against UC, and these findings will promote further research and clinical applications.

Radix Salvia miltiorrhiza for Ankylosing Spondylitis: Determining Potential Inflammatory Molecular Targets and Mechanism Using Network Pharmacology.

Radix Salvia miltiorrhiza (RSM) is widely used for the clinical improvement of inflammatory diseases. However, the actions of RSM in the treatment of ankylosing spondylitis (AS) have not been fully explored. Therefore, this study was designed to use retrospective clinical data mining approach to understand the effects of RSM on AS-related immuno-inflammatory processes, use network pharmacology to predict therapeutic targets of RSM, and to further investigate the pharmacological molecular mechanism in vitro. RSM treatment has a long-term correlation with the improvement of AS-related immuno-inflammatory indicators through computational models. We established protein-protein interaction networks, conducted KEGG analysis to enrich significant TNF pathways, and finally obtained three core targets of RSM in the treatment of AS, namely, prostaglandin endoperoxide synthase 2 (PTGS2), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha). Screening of RSM active ingredients with node degree greater than 20 yielded cryptotanshinone and tanshinone IIA, and previous studies have reported their anti-inflammatory effects. In vitro, both cryptotanshinone and tanshinone IIA significantly inhibited the expressions of PTGS2, IL-6, and TNF-α in peripheral blood mononuclear cells in AS patients. In conclusion, cryptotanshinone and tanshinone IIA, which are the active components of RSM, may inhibit the activation of TNF signaling pathway in AS patients by downregulating the expression of PTGS2, IL-6, and TNF-α. These findings illustrate that RSM may be a promising therapeutic candidate for AS, but further validation is required.

Scutellarin Loaded on Ultradeformable Nanoliposome Scutellarin EDTMP (S-UNL-E) Promotes Osteogenesis in Osteoporotic Rats.

Scutellarin is known as a safe, effective, and low-cost traditional Chinese medicine and has a variety of biological activities. Studies reported that the scutellarin loaded on ultradeformable nanoliposome scutellarin EDTMP (S-UNL-E) could promote osteoblast differentiation and bone formation in vitro. However, its effect on promoting osteogenesis in vivo is still unclear. In this study, pharmacology network and transcriptome sequencing were used to screen the potential targets and pathways of scutellarin in treating osteoporosis. The female Sprague-Dawley (SD) rats were operated on with bilateral oophorectomy and femoral defect to establish an osteoporosis model and then treated separately with bone dust, single scutellarin, 40 mg/kg ultradeformable nanoliposome scutellarin (S-UNL), and the optimal concentration of 40 mg/kg S-UNL-E for a total of 56 d to detect the parameters of trabecular bones. And qRT-PCR and western blot were performed to determine the expression of prostaglandin-endoperoxide synthase 2 (PTGS2), alkaline phosphatase (ALP), transcription factor 4 (TCF4), and β-catenin. Results of microscopic computed tomography (Micro-CT) of trabecular bones showed that single scutellarin, S-UNL, and S-UNL-E all promoted the bone formation of osteoporotic rats, in which S-UNL-E manifested the most remarkable therapeutic effect. And it is found that 40 mg/kg of S-UNL-E increased the expression of PTGS2, ALP, TCF4, and β-catenin, which indicated that S-UNL-E stimulated the secretion of ALP in bone defect areas to promote bone healing, and increased PTGS2 expression thereby enhancing the transcription and translation of key gene β-catenin and TCF4 in the Wnt/β-catenin signaling pathway to treat osteoporotic rats.

Studying the potential of upregulated PTGS2 and VEGF-C besides hyper-methylation of PTGS2 promoter as biomarkers of Acute myeloid leukemia.

Hereby, we aimed to investigate the expression of prostaglandin-endoperoxide synthase 2 (PTGS2) and Vascular Endothelial Factor-C (VEGF-C) besides the methylation of PTGS2 in AML patients. VEGF-C and PTGS2 expression analysis were evaluated in newly diagnosed AML patients and healthy controls by quantitative Reverse Transcriptase PCR method. Also, PTGS2 methylation status was evaluated by Methylation-Sensitive High-Resolution Melting Curve Analysis (MS-HRM). While 34% of patients were female, the mean age of the patients was 43.41 ± 17.60 years suffering mostly from M4 (48.21%) type of AML. Although methylation level between patients and controls was not significantly different, none of the normal controls showed methylation in the PTGS2 promoter. PTGS2 and VEGF-C levels were elevated in AML cases and correlated with WBC, Platelet, and Hemoglobin levels. The survival of patients with overexpressed VEGF-C and PTGS2 was poorer than others. It can be concluded that PTGS2 and especially VEGF-C expression but not PTGS2 methylation can be considered as diagnostic biomarkers for AML.

The Bradykinin System Contributes to the Regulation of Prostaglandin-Endoperoxide Synthase 2 Expression in Human Amnion Fibroblasts: Implications for Term and Preterm Birth.

BackgroundBradykinin (BK) and its biologically active metabolite des-Arg9 bradykinin (DABK) play a pivotal role in inflammation. Since chorioamnionitis is the leading cause of preterm birth and prostaglandin E2 (PGE2) derived from the amnion is key to labor initiation, we investigated if bradykinin peptides are part of the regulatory network of PGE2 synthesis in human amnion at parturition.MethodsHuman amnion tissue was obtained from term and preterm birth for the study of the changes of the bradykinin system at parturition. Cultured primary human amnion fibroblasts, the major source of PGE2, were used to study the effects of bradykinin peptides on PTGS2 expression and PGE2 production as well as the effects of infection mediators on bradykinin receptors.ResultsBradykinin peptides and their receptors BDKRB1 and BDKRB2 were present in human amnion, and their abundance increased in term and preterm labor. However, transcripts of the genes encoding the bradykinin precursor and its proteolytic cleavage enzymes were hardly detectable in human amnion despite the increased abundance of bradykinin peptides in term and preterm labor, suggesting that there is an alternative source of bradykinin peptides for human amnion and their actions are enhanced in human amnion at parturition. In-vitro studies in cultured human amnion fibroblasts showed that both BK and DABK increased the expression of prostaglandin-endoperoxide synthase 2 (PTGS2), the rate-limiting enzyme in prostaglandin synthesis, and subsequent PGE2 production. These effects of BK and DABK were mediated through BDKRB2 and BDKRB1 receptors, respectively, with subsequent activation of the p38 and ERK1/2 pathways. Moreover, lipopolysaccharide (LPS) and serum amyloid A1 (SAA1), the important mediators of infectious inflammation, induced the expression of both BDKRB1 and BDKRB2 through toll-like receptor 4 (TLR4). Induction of BDKRB1 and BDKRB2 expression by LPS and SAA1 enhanced BK- or DABK-induced PTGS2 expression and PGE2 production in human amnion fibroblasts.ConclusionsThis study demonstrated for the first time that the human amnion is a target tissue of bradykinin peptides and the bradykinin system may be part of the regulatory network of PTGS2 expression and PGE2 production in human amnion fibroblasts at both term and preterm birth, which may be enhanced by infection.

Effects of Omega‐6 Fatty Acids on Interleukin‐6, Phospholipase A2, and Prostaglandin‐Endoperoxide Synthase 2 Gene Expression in Lipopolysaccharide‐Challenged Murine Macrophages and Adipocytes

Obese adipose tissue (AT) has been described as an organ involved in meta‐inflammation‐a chronic low‐grade inflammation linked to the predisposition to chronic diseases. Both adipocytes and macrophages are found in AT, with obese AT containing a higher percentage of macrophages compared to lean AT. Adipocytes and macrophages can produce pro‐inflammatory molecules (adipokines), with research showing that the macrophage is the primary contributor to inflammatory adipokine release by obese AT. Our lab has described differential effects of omega‐6 (n‐6) fatty acids (FAs) on the production of adipokines by 3T3‐L1 murine adipocytes and RAW 264.7 murine macrophages. The objective of this study was to compare the effects of n‐6 FAs on gene expression of inflammation‐related molecules in 3T3‐L1 and RAW264.7. Gene expression of interleukin‐6 (IL‐6), prostaglandin‐endoperoxide synthase‐2 (PTGS2), and phospholipase A2 (PLA2) were quantified in both of these cell lines after incubation with n‐6 FAs and a lipopolysaccharide (LPS) challenge. PGTS2 and PLA2 are enzymes involved in the production of inflammatory eicosanoids, while the IL‐6 gene codes for the IL‐6 protein. Macrophages were pre‐incubated with 100 μM of linoleic acid (LA; n‐6) or arachidonic acid (ARA; n‐6) for 24 h, followed by a 6 h, 0.01 μg/ml LPS challenge. Fibroblasts (3T3‐L1) were differentiated into adipocytes with the addition of 100 μM of one of the n‐6 FAs throughout the differentiation period, followed by a 6 h, 1 μg/ml LPS challenge once they were fully differentiated. After LPS challenge, RNA was extracted for quantitative PCR analysis. Fatty acid treatments had no effect on expression of the target genes (IL‐6, PTGS2, PLA2) in 3T3‐L1 cells (two‐way ANOVA). PTGS2 expression was downregulated in LA (0.24 ± 0.13 2ΔΔCt) and ARA (0.16 ± 0.13 2ΔΔCt)‐treated macrophages challenged with LPS compared to control (1.07 ± 0.13 2ΔΔCt) and LPS (1.70 ± 0.13 2ΔΔCt)‐challenged macrophages (two‐way ANOVA; p&lt;0.0001). There were no significant LPS or LPS+n‐6 FA effects on gene expression of IL‐6 and PLA2in macrophages (two‐way ANOVA). Time‐response experimentation is necessary to determine the kinetic model of gene expression of these target genes in both cell lines.

Exploration of the Potential Mechanism of Qi Yin San Liang San Decoction in the Treatment of EGFRI-Related Adverse Skin Reactions Using Network Pharmacology and In Vitro Experiments.

BackgroundAdverse skin reactions are the most common side effects of epidermal growth factor receptor inhibitors (EGFRIs) in the treatment of cancer, significantly affecting the survival rate and quality of life of patients. Qi Yin San Liang San Decoction (QYSLS) comes from folk prescription and is currently used in the clinical treatment of adverse skin reactions caused by EGFRIs. However, its therapeutic mechanism remains unclear.ObjectivesTo explore the potential mechanism of QYSLS in the treatment of adverse skin reactions caused by EGFR inhibition using network pharmacology and experimental research.MethodsFirst, we verified the effectiveness of QYSLS in vivo using model mice. Second, the related targets of adverse skin reactions associated with EGFR inhibition were predicted by the Gene Expression Omnibus (GEO) database, and effective components and predictive targets of QYSLS were analyzed by Traditional Chinese Medicine Systems Pharmacology (TCMSP) and Batman-TCM databases. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed via the Bioconductor (R) V3.8 bioinformatics software. Molecular docking studies verified the selected key ingredients and targets. Finally, the results of network pharmacology were verified by in vitro experiments.ResultsIn the in vivo mouse model, QYSLS effectively reduced the occurrence of skin side effects. Network pharmacological results showed that the active ingredient luteolin, quercetin, licochalcone a, and kaempferol and the effective targets prostaglandin-endoperoxide synthase 2 (PTGS2), matrix metallopeptidase 9 (MMP9), and C–C motif chemokine ligand 2 (CCL2) were related to the interleukin-17 (IL-17) and tumor necrosis factor (TNF) pathway. Subsequently, the related active compounds and targets were verified using HaCaT cells as an in vitro adverse reaction model. The results showed that luteolin and quercetin increased the expression of PTGS2 and MMP9 and reduced the expression of CCL2 in HaCaT cells treated with gefitinib.ConclusionsThe results revealed that QYSLS effectively treats EGFRI-related adverse skin reactions through multi-target and multi-pathway mechanisms. Luteolin and quercetin may be the core active ingredients of QYSLS in the treatment of EGFRI-related adverse skin reactions, and their therapeutic effects are potentially mediated through PTGS2, CCL2, and MMP9 in the IL-17 and TNF signaling pathway.

The CTCF/LncRNA-PACERR complex recruits E1A binding protein p300 to induce pro-tumour macrophages in pancreatic ductal adenocarcinoma via directly regulating PTGS2 expression.

BackgroundTumour‐associated macrophages (TAMs) play an important role in promoting the progression of pancreatic ductal adenocarcinoma (PDAC). Here, we aimed to study the epigenetic mechanisms in regulating pro‐tumour M2‐polarised TAMs in the PDAC tumour microenvironment.MethodsThis study was conducted based on ex vivo TAMs isolated from PDAC tissues and in vitro THP1‐derived TAM model. RNA‐sequencing (RNA‐seq), assay for transposase‐accessible chromatin with sequencing and chromatin immunoprecipitation sequencing were performed to investigate gene expression, chromatin accessibility, transcription factor binding sites and histone modifications. Gene knockdown in THP1‐derived TAMs was performed with lentivirus, and the impact of THP1‐derived TAMs on invasion and metastasis ability of PDAC cells were investigated with in vitro and in vivo functional assays. RNA‐chromatin interaction was analysed by chromatin isolation through RNA purification with sequencing. RNA‐protein interaction was studied by RNA immunoprecipitation and RNA pull‐down.ResultsOur data showed that the transcription factor CTCF (CCCTC‐binding factor) was highly expressed in TAMs and predicted to be significantly enriched in hyper‐accessible chromatin regions when compared to monocytes. High infiltration of CTCF+ TAMs was significantly associated with poor prognosis in PDAC patients. Knockdown of CTCF in THP1‐derived TAMs led to the down‐regulation of specific markers for M2‐polarised TAMs, including CD206 and CD163. When THP1‐derived TAMs with CTCF knockdown, they showed a decreased ability of invasion and metastasis. Further integrative analysis of multi‐omics data revealed that prostaglandin‐endoperoxide synthase 2 (PTGS2) and PTGS2 antisense NF‐κB1 complex‐mediated expression regulator RNA (PACERR) were critical downstream targets of CTCF and positively correlated with each other, which are closely situated on a chromosome. Knockdown of PACERR exhibited a similar phenotype as observed in CTCF knockdown THP1‐derived TAMs. Moreover, PACERR could directly bind to CTCF and recruit histone acetyltransferase E1A binding protein p300 to the promoter regions of PACERR and PTGS2, thereby enhancing histone acetylation and gene transcription, promoting the M2 polarization of TAMs in PDAC.ConclusionsOur study demonstrated a novel epigenetic regulation mechanism of promoting pro‐tumour M2‐polarised TAMs in the PDAC tumour microenvironment.