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.

AIM: 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. METHODOLOGY: 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. RESULTS: 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. CONCLUSIONS: 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.

Decreased fertility in female mice lacking urokinase plasminogen activator.

It is well established that mouse ovarian granulosa cells secrete urokinase plasminogen activator (uPA) under gonadotropin stimulation. The synthesis and secretion of the enzyme correlate well with the time of follicular rupture in vivo. Moreover, uPA is secreted by the trophoblast at the time of implantation. In the present study, we have analyzed whether the absence of uPA could influence follicular growth, ovulation, and embryo implantation. Our data show fewer preantral follicles in uPA-/- ovaries but no decrease in hormonally induced ovulation. However, we observed a significant decrease in the number of implanted embryos in uPA-/- animals and, therefore, a lower number of pups per family. Adding uPA to the epithelial and stromal uterine cell culture medium strongly upregulates the expression of prostaglandin-endoperoxide synthase 2 (Ptgs2), the enzyme required for prostaglandin production and embryo implantation. The uPA inhibitor amiloride abrogated this increase.

Effect of "Tongdu Qishen" acupuncture on expressions of ferroptosis-related factors in the hippocampus of APPswe/PS1dE9 Mice. / "通督启神"针法对APPswe/PS1dE9å°é¼ æµ·é©¬é“æ­»äº¡ç›¸å ³å› å­è¡¨è¾¾çš„å½±å“.

OBJECTIVES: To investigate the effect of "Tongdu Qishen" acupunctureï¼»dredging the Govern Vessel and normalizing mental activities, electroacupuncture (EA) of "Baihui" (GV20), "Yintang" (EX-HN3) and "Shuigou" (GV26) needlingï¼½on the learning-memory ability and the mechanism of ferroptosis in Alzheimer's disease (AD) mice. METHODS: Twenty-four male APPswe/PS1dE9 mice were randomly and equally divided into model group and EA group, and 12 normal C57BL/6 mice were used as the control group. In the EA group, EA (2 Hz/100 Hz, 20 min) was applied to GV20 and EX-HN3 in combination with manual acupuncture stimulation of GV26. The treatment was performed once a day, for a total of 28 days. The mice in the three groups were given the same fixation and grasping operation. Morris water maze swimming tests were used to assess the mice's learning-memory ability. Nissl staining and transmission electron microscopy were used to observe the morphological changes of neurons in the hippocampus. The activity of superoxide dismutase (SOD) in the hippocampus tissue was detected by superoxide anionic colorimetric assay kit (WST-1), and malondialdehyde (MDA) contents were detected by thiobarbituric acid (TBA) method. The expression levels of prostaglandin endoperoxide synthase 2 (ptgs2) and glutathione peroxidase 4 (GPX4) mRNA in the hippocampus were detected by fluorescent quantitative real-time PCR. RESULTS: Behavioral results showed that compared with the control group, the escape latencies at the 2nd, 3rd, 4th and 5th day of Morris water maze swimming test were significantly increased (P<0.05), and the swimming time in the original platform quadrant and the times of cros-sing the original platform were considerably decreased (P<0.05) in the model group. In comparison with the model group, the escape latencies at the 4th and 5th day were strikingly decreased (P<0.05), and the swimming time in the original platform quadrant and times of crossing the original platform significantly increased (P<0.05) in the EA group. Following modeling, the SOD activity and the expression of GPX4 mRNA were obviously down-regulated (P<0.05), and the content of MDA and the expression of ptgs2 mRNA significantly up-regulated (P<0.05) in the model group rele-vant to the control group. The SOD activity and the expression of GPX4 mRNA were apparently increased (P<0.05), and the content of MDA and the expression of ptgs2 mRNA remarkably down-regulated (P<0.05) in the EA group rele-vant to the model group. Histopathological and ultrastructural results showed scattered arrangement of cells, widened space among cells, reduction in the number of cells, and many shrunk of dissolved nucleoli, shrunking and incomplete mitochondria, and high membrane electron density in the hippocampus of the model group, which was relatively milder in the EA group. CONCLUSIONS: "Tongdu Qishen" acupuncture can improve the learning-memory ability of AD mice, which may be related to its functions in up-regulating SOD activity and GPX4 mRNA expression, and down-regulating MDA content and ptgs2 mRNA expression to reduce the lipid peroxidation in the process of ferroptosis.

The role of CcPTGS2a in immune response against Aeromonas hydrophila infection in common carp (Cyprinus carpio).

Prostaglandin-endoperoxide synthase 2 (PTGS2), a crucial enzyme in prostaglandin synthesis, catalyzes the conversion of arachidonic acid to prostaglandins and plays a significant role in the inflammatory response. This investigation aimed to determine the regulatory role of PTGS2a in the innate immune response to bacterial infection in fish. To achieve this objective, the CcPTGS2a gene was identified and characterized in common carp (Cyprinus carpio), and its function in immune defense was investigated. According to the sequence and structural analysis results, CcPTGS2a had an open reading frame of 1806 bp that encoded 602 amino acids. It was estimated that the protein's theoretical molecular weight was 69.0 kDa, and its isoelectric point was 8.10. The structure of CcPTGS2a was observed to be conserved, with an epidermal growth factor domain and a peroxidase domain present. Moreover, the amino acid sequence of CcPTGS2a exhibited significant homology with the amino acid sequences of several fish species. CcPTGS2a mRNA was detected in the healthy tissues of common carp, with higher expression in the head kidney, spleen, gills, and liver. Following the challenges with Aeromonas hydrophila and lipopolysaccharide, CcPTGS2a mRNA showed unique geographic and temporal expression patterns, with significant increases detected in the head kidney, gills, spleen, and liver. Additionally, the recombinant CcPTGS2a protein exhibited detectable bacterial binding to various bacteria. As determined by subcellular localization analysis, CcPTGS2a was predominantly localized in the nucleus and cytoplasm. Furthermore, it was discovered that the overexpression of CcPTGS2a stimulated the up-regulation of ferroptosis-related genes and inflammatory cytokine mRNA expression in fish and EPC (Epithelioma papulosum cyprinid) cells while concurrently reducing the bacterial load of A. hydrophila. In contrast, the interference of CcPTGS2a decreased the mRNA expression of ferroptosis-related genes and inflammatory cytokines in fish and EPC cells and increased the bacterial load of A. hydrophila. Notably, A. hydrophila stimulation resulted in the up-regulation of CcPTGS2a protein expression in EPC cells. These results suggested that CcPTGS2a was involved in the immune response to bacterial infections in common carp.

Ferroptosis model system by the re-expression of BACH1.

Ferroptosis is a regulated cell death induced by iron-dependent lipid peroxidation. The heme-responsive transcription factor BTB and CNC homology 1 (BACH1) promotes ferroptosis by repressing the transcription of genes involved in glutathione (GSH) synthesis and intracellular labile iron metabolism, which are key regulatory pathways in ferroptosis. We found that BACH1 re-expression in Bach1-/- immortalized mouse embryonic fibroblasts (iMEFs) can induce ferroptosis upon 2-mercaptoethanol removal, without any ferroptosis inducers. In these iMEFs, GSH synthesis was reduced, and intracellular labile iron levels were increased upon BACH1 re-expression. We used this system to investigate whether the major ferroptosis regulators glutathione peroxidase 4 (Gpx4) and apoptosis-inducing factor mitochondria-associated 2 (Aifm2), the gene for ferroptosis suppressor protein 1, are target genes of BACH1. Neither Gpx4 nor Aifm2 was regulated by BACH1 in the iMEFs. However, we found that BACH1 represses AIFM2 transcription in human pancreatic cancer cells. These results suggest that the ferroptosis regulators targeted by BACH1 may vary across different cell types and animal species. Furthermore, we confirmed that the ferroptosis induced by BACH1 re-expression exhibited a propagating effect. BACH1 re-expression represents a new strategy for inducing ferroptosis after GPX4 or system Xc- suppression and is expected to contribute to future ferroptosis research.

Tongqiao Huoxue decoction alleviates neurological impairment following ischemic stroke via the PTGS2/NF-kappa B axis.

Traditional Chinese medicine has emerged as promising targets for ischemic stroke (IS) therapy, yet the mechanism remains elusive. The current study was performed with an aim to investigate the action and mechanism of Tongqiao Huoxue decoction (TQHXD) affecting the neurological impairment secondary to IS based on network pharmacology. Based on network pharmacology and bioinformatics analysis, target genes and pathways involved in the treatment of TQHXD against IS were predicted. Serum containing TQHXD was prepared through blood collection from C57BL/6 mice after intragastric administration of TQHXD. The main results exhibited that Prostaglandin-endoperoxide synthase 2 (PTGS2) exhibited an abundance in IS and enrichment in the NF-kappa B signaling pathway, holding the potential as targets related to TQHXD treatment for IS. TQHXD was found to rescue cell viability, inhibit apoptosis, and alleviate inflammation under oxygen and glucose deprivation and reoxygenation (OGD/R) exposure. Furthermore, our in vivo experiment validated the protective function of TQHXD in ischemic brain damage stimulated by middle cerebral artery occlusion (MCAO). This protective action of TQHXD could be attenuated by overexpressing nuclear factor (NF)-kappa B, which was dependent on PTGS2. Collectively, TQHXD was demonstrated to ameliorate IS-induced neurological impairment by blocking the NF-kappa B signaling pathway and down-regulating PTGS2.

The PTGS1 (rs1330344) CC Genotype Contributes to Susceptibility to Kawasaki Disease in Southern Chinese Children.

Kawasaki disease (KD) is an acute systemic vascular disease complicated by coronary artery injury. Although polymorphisms in prostaglandin-endoperoxide synthase 1 (PTGS1) are being increasingly explored in cardiovascular diseases, little is known regarding the connection between PTGS1 polymorphisms and KD risk. We evaluated 834 KD patients and 1474 healthy controls to explore the relationship between PTGS1 polymorphisms (rs1330344 and rs5788) and KD risk. Our results showed that the rs1330344 CC genotype was significantly associated with KD risk and coronary artery injury in children with KD. In combined analysis, individuals with 1-2 unfavorable genotypes had an increased risk of KD, compared with those with no risk genotype. Stratified analysis indicated that the rs1330344 CC genotype is strongly associated with increased risk of KD in children aged ≤60 months and females. Moreover, carrying 1-2 of these SNP genotypes had a higher risk of KD than those who harbored none of them in children ≤60 months of age and females; the risk of coronary artery dilatations/small aneurysms and medium/giant aneurysms was also significantly increased in KD patients. In summary, the PTGS1 rs1330344 CC genotype is associated with increased susceptibility to KD, which may contribute to KD pathogenesis and serve as a genetic biomarker.

Identification and Validation of PTGS2 Gene as an Oxidative Stress-Related Biomarker for Arteriovenous Fistula Failure.

(1) Background: Arteriovenous fistulas (AVFs) are the preferred site for hemodialysis. Unfortunately, approximately 60% of patients suffer from AVF failure within one year. Oxidative stress plays an important role in the occurrence and development of AVF. However, the underlying mechanisms remain unclear. Therefore, specific oxidative stress-related biomarkers are urgently needed for the diagnosis and treatment of AVF failure. (2) Methods: Bioinformatics analysis was carried out on dataset GSE119296 to screen for PTGS2 as a candidate gene related to oxidative stress and to verify the expression level and diagnostic efficacy of PTGS2 in clinical patients. The effects of NS398, a PTGS2 inhibitor, on hemodynamics, smooth muscle cell proliferation, migration, and oxidative stress were evaluated in a mouse AVF model. (3) Results: Based on 83 oxidative stress-related differentially expressed genes, we identified the important pathways related to oxidative stress. PTGS2 may have diagnostic and therapeutic efficacy for AVF failure. We further confirmed this finding using clinical specimens and validation datasets. The animal experiments illustrated that NS398 administration could reduce neointimal area (average decrease: 49%) and improve peak velocity (average increase: 53%). (4) Conclusions: Our study identified PTGS2 as an important oxidative stress-related biomarker for AVF failure. Targeting PTGS2 reduced oxidative stress and improved hemodynamics in an AVF mouse model.

Morinda officinalis polysaccharide enable suppression of osteoclastic differentiation by exosomes derived from rat mesenchymal stem cells.

CONTEXT: Morinda officinalis F.C. How. (MO) (Rubiaceae) can strengthen bone function. OBJECTIVE: To examine the functional mechanism and effect of MO polysaccharides (MOPs) in rats with glucocorticoid-induced osteoporosis (GIOP). MATERIALS AND METHODS: Rats with GIOP were treated with 5, 15 or 45 mL/kg of MOP [n = 15 for each dose, intraperitoneal (i.p.) injection every other day for 8 weeks]. The body weight of rats and histomorphology of bone tissues were examined. Bone marrow mesenchymal stem cells (BMSCs)-derived exosomes (Exo) were collected and identified. Bone marrow-derived macrophages (BMMs) were induced to differentiate into osteoclasts and treated with BMSC-Exo for in vitro studies. RESULTS: MOP reduced the body weight (5, 15, or 45 mg/kg MOP vs. phosphate-buffered saline: 8%, 15% and 25%, p < 0.01), elevated the bone volume to tissue volume (BV/TV), mean trabecular thickness (Tb.Th), mean trabecular number (Tb.N) and mean connectivity density (Conn.D) (40-86%, p < 0.01), decreased the mean trabecular separation/spacing (Tb.Sp) (22-37%, p < 0.01), increased the cortical bone continuity (35-90%, p < 0.01) and elevated RUNX family transcription factor 2 and RANK levels (5-12%, p < 0.01), but suppressed matrix metallopeptidase 9 and cathepsin K levels (9-20%, p < 0.01) in femur tissues. BMSC-Exo from MOP-treated rats (MOP-Exo) suppressed osteoclastic differentiation and proliferation of BMMs. The downregulation of microRNA-101-3p (miR-101-3p) or the upregulation of prostaglandin-endoperoxide synthase 2 (PTGS2) blocked the functions of MOP-Exo. DISCUSSION AND CONCLUSIONS: MOP inhibits osteoclastic differentiation and could potentially be used for osteoporosis management. This suppression may be enhanced by the upregulation of miR-101-3p or the inhibition of PTGS2.

MiR-214-3p Prevents the Development of Perioperative Neurocognitive Disorders in Elderly Rats.

OBJECTIVE: This study aimed to identify microRNAs (miRNAs) involved in the development of perioperative neurocognitive disorders (PND). METHODS: Plasma exosomal miRNA expression was examined in patients before and after cardiopulmonary bypass (CPB) using microarray and qRT-PCR and these patients were diagnosed as PND later. Elderly rats were subjected to CPB, and the cognitive functions were examined. Bioinformatics analysis was conducted to predict the targets of miR-214-3p. Rats were administered rno-miR-214-3p agomir before or after CPB to investigate the role of miR-214-3p in PND development. RESULTS: We identified 76 differentially expressed plasma exosomal miRNAs in PND patients after surgery (P<0.05, ∣log2FC∣>0.58), including the upregulated hsa-miR-214-3p (P=0.002399392). Prostaglandin-endoperoxide synthase 2 (PTGS2) was predicted as a miR-214-3p target. In rats, CPB reduced the platform crossing numbers and target quadrant stay time, accompanied with hippocampal neuronal necrosis. The rno-miR-214-3p level was significantly increased in plasma exosomes but decreased in rat hippocampus after surgery, exhibiting a negative correlation (P<0.001, r=-0.762). A negative correlation between miR-214-3p and PTGS2 protein expression was also observed in the hippocampus after surgery. Importantly, rno-miR-214-3p agomir treatment, before or after surgery, significantly increased the platform crossing numbers (P=0.035) and target quadrant stay time (P=0.029) compared with negative control. Hippocampal PTGS2 protein level was increased in the untreated surgery group and decreased in response to rno-miR-214-3p agomir treatment before or after surgery (both P<0.05 vs. negative control). CONCLUSION: These data suggest that miR-214-3p/PTGS2 signaling contributes to the development of PND, serving as a potential therapeutic target for PND.

NMDA receptor-dependent prostaglandin-endoperoxide synthase 2 induction in neurons promotes glial proliferation during brain development and injury.

Astrocytes play critical roles in brain development and disease, but the mechanisms that regulate astrocyte proliferation are poorly understood. We report that astrocyte proliferation is bi-directionally regulated by neuronal activity via NMDA receptor (NMDAR) signaling in neurons. Prolonged treatment with an NMDAR antagonist reduced expression of cell-cycle-related genes in astrocytes in hippocampal cultures and suppressed astrocyte proliferation in vitro and in vivo, whereas neuronal activation promoted astrocyte proliferation, dependent on neuronal NMDARs. Expression of prostaglandin-endoperoxide synthase 2 (Ptgs2) is induced specifically in neurons by NMDAR activation and is required for activity-dependent astrocyte proliferation through its product, prostaglandin E2 (PGE2). NMDAR inhibition or Ptgs2 genetic ablation in mice reduced the proliferation of astrocytes and microglia induced by mild traumatic brain injury in the absence of secondary excitotoxicity-induced neuronal death. Our study defines an NMDAR-mediated signaling mechanism that allows trans-cellular control of glial proliferation by neurons in brain development and injury.

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

BACKGROUND: Tumour-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. METHODS: This 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. RESULTS: Our 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. CONCLUSIONS: Our study demonstrated a novel epigenetic regulation mechanism of promoting pro-tumour M2-polarised TAMs in the PDAC tumour microenvironment.

Differential Expression of miR-381-3p in Alzheimer's Disease Patients and Its Role in Beta-Amyloid-Induced Neurotoxicity and Inflammation.

INTRODUCTION: This study aimed to explore the diagnostic value and effect of miR-381-3p on Alzheimer's disease (AD). METHODS: RT-qPCR was used for the measurement of miR-381-3p levels. Pearson correlation coefficient was used for the correlation analysis. Receiver operating characteristic (ROC) curve was constructed to assess the distinct ability of miR-381-3p for AD. SH-SY5Y cells were treated with Aß25-35 to establish an AD cell model. The role of miR-381-3p on cell proliferation and apoptosis was detected. ELISA was applied to detect the protein levels of inflammatory cytokine expression. The target relationship of miR-381-3p with PTGS2 was verified by luciferase reporter gene assay. RESULTS: Low expression of miR-381-3p was detected in the serum of AD patients and cell models. There was a negative association of serum miR-381-3p with the serum inflammatory cytokines. The ROC curve demonstrated the distinct ability of serum miR-381-3p for AD, with the AUC value of 0.898, with a sensitivity of 87.5%, and a specificity of 77.7%. Overexpression of miR-381-3p reversed the influence of Aß25-35 on cell proliferation and apoptosis, but miR-381-3p downregulation exacerbated the influence. miR-381-3p overexpression inhibited the release of IL-6, IL-1ß, and TNF-α induced by Aß25-35 treatment, whereas miR-381-3p downregulation further promoted the release of inflammatory cytokines. PTGS2 was the target gene of miR-381-3p and was upregulated in AD cell models. CONCLUSION: miR-381-3p is less expressed in the serum of AD patients and has potential diagnostic values for AD. Overexpression of miR-381-3p may attenuate Aß25-35-induced neurotoxicity and inflammatory responses via targeting PTGS2 in SH-SY5Y cells.

Fluoxetine-induced hepatic lipid accumulation is mediated by prostaglandin endoperoxide synthase 1 and is linked to elevated 15-deoxy-Δ12,14 PGJ2.

Major depressive disorder and other neuropsychiatric disorders are often managed with long-term use of antidepressant medication. Fluoxetine, an SSRI antidepressant, is widely used as a first-line treatment for neuropsychiatric disorders. However, fluoxetine has also been shown to increase the risk of metabolic diseases such as non-alcoholic fatty liver disease. Fluoxetine has been shown to increase hepatic lipid accumulation in vivo and in vitro. In addition, fluoxetine has been shown to alter the production of prostaglandins which have also been implicated in the development of non-alcoholic fatty liver disease. The goal of this study was to assess the effect of fluoxetine exposure on the prostaglandin biosynthetic pathway and lipid accumulation in a hepatic cell line (H4-II-E-C3 cells). Fluoxetine treatment increased mRNA expression of prostaglandin biosynthetic enzymes (Ptgs1, Ptgs2, and Ptgds), PPAR gamma (Pparg), and PPAR gamma downstream targets involved in fatty acid uptake (Cd36, Fatp2, and Fatp5) as well as production of 15-deoxy-Δ12,14 PGJ2 a PPAR gamma ligand. The effects of fluoxetine to induce lipid accumulation were attenuated with a PTGS1 specific inhibitor (SC-560), whereas inhibition of PTGS2 had no effect. Moreover, SC-560 attenuated 15-deoxy-Δ12,14 PGJ2 production and expression of PPAR gamma downstream target genes. Taken together these results suggest that fluoxetine-induced lipid abnormalities appear to be mediated via PTGS1 and its downstream product 15d-PGJ2 and suggest a novel therapeutic target to prevent some of the adverse effects of fluoxetine treatment.

Systematic analysis of potential targets of the curcumin analog pentagamavunon-1 (PGV-1) in overcoming resistance of glioblastoma cells to bevacizumab.

BACKGROUND: Glioblastoma is one of the most aggressive and deadliest malignant tumors. Acquired resistance decreases the effectiveness of bevacizumab in glioblastoma treatment and thus increases the mortality rate in patients with glioblastoma. In this study, the potential targets of pentagamavunone-1 (PGV-1), a curcumin analog, were explored as a complementary treatment to bevacizumab in glioblastoma therapy. METHODS: Target prediction, data collection, and analysis were conducted using the similarity ensemble approach (SEA), SwissTargetPrediction, STRING DB, and Gene Expression Omnibus (GEO) datasets. Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were conducted using Webgestalt and DAVID, respectively. Hub genes were selected based on the highest degree scores using the CytoHubba. Analysis of genetic alterations and gene expression as well as Kaplan-Meier survival analysis of selected genes were conducted with cBioportal and GEPIA. Immune infiltration correlations between selected genes and immune cells were analyzed with database TIMER 2.0. RESULTS: We found 374 targets of PGV-1, 1139 differentially expressed genes (DEGs) from bevacizumab-resistant-glioblastoma cells. A Venn diagram analysis using these two sets of data resulted in 21 genes that were identified as potential targets of PGV-1 against bevacizumab resistance (PBR). PBR regulated the metabolism of xenobiotics by cytochrome P450. Seven potential therapeutic PBR, namely GSTM1, AKR1C3, AKR1C4, PTGS2, ADAM10, AKR1B1, and HSD17B110 were found to have genetic alterations in 1.2%-30% of patients with glioblastoma. Analysis using the GEPIA database showed that the mRNA expression of ADAM10, AKR1B1, and HSD17B10 was significantly upregulated in glioblastoma patients. Kaplan-Meier survival analysis showed that only patients with low mRNA expression of AKR1B1 had significantly better overall survival than the patients in the high mRNA group. We also found a correlation between PBR and immune cells and thus revealed the potential of PGV-1 as an immunotherapeutic agent via targeting of PBR. CONCLUSION: This study highlighted seven PBR, namely, GSTM1, AKR1C3, AKR1C4, PTGS2, ADAM10, AKR1B1, and HSD17B110. This study also emphasized the potential of PBR as a target for immunotherapy with PGV-1. Further validation of the results of this study is required for the development of PGV-1 as an adjunct to immunotherapy for glioblastoma to counteract bevacizumab resistance.

Pulmonary surfactant-associated protein B regulates prostaglandin-endoperoxide synthase-2 and inflammation in chronic obstructive pulmonary disease.

NEW FINDINGS: What is the central question of this study? It is reported that polymorphism of the gene for pulmonary surfactant-associated protein B (SFTPB) is associated with chronic obstructive pulmonary disease (COPD): what are the function and mechanism of action of SFTPB in COPD? What is the main finding and its importance? Under stimulation of the risk factors of COPD, SFTPB expression is decreased, which may be involved in the formation of COPD. The progress of COPD induces an inflammatory response and reduces SFTPB expression. Levels of prostaglandin-endoperoxide synthase-2 (PTGS2) and inflammatory responses are changed by SFTPB, which indicates that SFTPB promotes the progression of COPD by PTGS2 and inflammation. ABSTRACT: Pulmonary surfactant-associated protein B (SFTPB) is a critical protein for lung homeostasis, and polymorphism of its gene is associated with chronic obstructive pulmonary disease (COPD). However, few studies have so far confirmed the functional involvement of SFTPB in COPD. Serum SFTPB and inflammatory cytokine levels were measured in 54 patients with acute exacerbation of COPD and 29 healthy controls. A549 cells were induced using 10% cigarette smoke extract (CSE) and treated with dexamethasone to investigate the effect of inflammation on SFTPB expression, and the effect of SFTPB overexpression and silencing on inflammatory cytokines was measured using real-time PCR and enzyme-linked immunosorbent assay. SFTPB expression was assessed in mouse lung tissues using immunofluorescence. Serum levels of SFTPB were significantly lower in COPD patients than in controls (P = 0.009). Conversely, levels of interleukin (IL)-6 and prostaglandin-endoperoxide synthase-2 (PTGS2) were increased in COPD patients (IL-6: P = 0.006; PTGS2: P = 0.043). After CSE treatment, SFTPB mRNA and protein levels were significantly decreased compared to controls (mRNA: P = 0.002; protein: P = 0.011), while IL-6, IL-8 and PTGS2 were elevated. Dexamethasone treatment increased SFTPB levels. Following overexpression of SFTPB in A549 cells, mRNA and protein levels of IL-6, IL-8 and PTGS2 were significantly reduced, while gene silencing induced the opposite effect. SFTPB levels were significantly reduced in the lung tissue of a mouse model of COPD compared to controls. Reduced SFTPB levels may induce PTGS2 and inflammatory responses in COPD and SFTPB could be a key protein for evaluation of COPD progression.

Genetic Variations in Prostaglandin E2 Pathway Identified as Susceptibility Biomarkers for Gastric Cancer in an Intermediate Risk European Country.

The cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) pathway exerts deleterious pleiotropic effects in inflammation-induced gastric carcinogenesis. We aimed to assess the association of genetic variants in prostaglandin-endoperoxide synthase 2 (PTGS2), ATP binding cassette subfamily C member 4 (ABCC4), hydroxyprostaglandin dehydrogenase 15-(NAD) (HPGD), and solute carrier organic anion transporter family member 2A1 (SLCO2A1) PGE2 pathway-related genes with gastric cancer (GC) risk in a European Caucasian population. A hospital-based case-control study gathering 260 GC cases and 476 cancer-free controls was implemented. Using a tagSNP approach, 51 single nucleotide polymorphisms (SNPs) were genotyped through MassARRAY® iPLEX Gold Technology or allelic discrimination by real-time polymerase chain reaction (PCR). Homozygous carriers of the minor allele for both rs689466 and rs10935090 SNPs were associated with a 2.98 and 4.30-fold increased risk for GC, respectively (95% confidence interval (CI): 1.14-7.74, p = 0.027; 95% CI: 1.22-15.16, p = 0.026), with the latter also being associated with an anticipated diagnosis age. A multifactor dimensionality reduction analysis identified an overall three-factor best interactive model composed of age, rs689466, and rs1678374 that was associated with a 17.6-fold GC increased risk (95% CI: 11.67-26.48, p < 0.0001, (cross-validation) CV consistency of 8/10 and accuracy of 0.807). In this preliminary study, several tagSNPs in PGE2 pathway-related genes were identified as risk biomarkers for GC development. This approach may help to identify higher-risk individuals and may contribute to the tailoring screening of GC in intermediate-risk European countries.

Expression of Transcript Variants of PTGS1 and PTGS2 Genes among Patients with Chronic Rhinosinusitis with Nasal Polyps.

To date, there has been no reliable test to identify unfavorable course of Chronic Rhinosinusitis with Nasal Polyps (CRSwNP), especially in aspirin intolerant patients. The research aimed to analyze the expression of transcript variants of PTGS1 and PTGS2 genes in the pathobiology of the disease. The study was performed on 409 adult patients: 206 CRSwNP patients including 44 (21.36%) aspirin intolerant patients and 203 healthy volunteers in the control group. Transcript variants of the PTGS1 and PTGS2 genes named as follows: COX1.1 for NM_000962, COX1.2 for NM_080591, COX1.3 for NM_001271165.1, COX1.4 for NM_001271368.1, COX1.5 for NM_001271166.1, COX2.1 for NM_000963.3, COX2.2 for AY_151286 and COX2.3 for BQ_722004 were confirmed using direct sequencing and quantified using targeted qPCR. The coexistence of all examined transcript variants in the study and the control group and significant differences between both were found. In aspirin sensitive patients, the levels of COX1.2, COX1.3, COX1.4 and COX1.5 isoforms were higher compared to aspirin-tolerant patients. The severity of symptoms was bigger in patients with higher expressions of variants: COX1.1 (R with dCt = -0.134; p = 0.0490), COX1.3 (R = -0.1429; p = 0.0400) and COX1.5 (Rs = -0.1499; p = 0.032). The expression of COX1.1 (Rs = -0.098; p = 0.049) and COX1.5 (Rs = -0.141; p = 0.043) isoforms increased with polyposis advancement in endoscopy. With the CT extent of sinuses opacification, COX1.1 isoform also significantly increased (Rs = -0.163; p = 0.020). The isoforms COX1.3, COX1.4, COX1.5 and COX2.1 may promote milder CRSwNP course. On the contrary, the variants COX1.1, COX1.2 and COX2.2 may be involved in a more aggressive disease.

Deciphering the Effective Constituents and Mechanisms of Portulaca oleracea L. for Treating NASH via Integrating Bioinformatics Analysis and Experimental Pharmacology.

Nonalcoholic steatohepatitis (NASH) is a highly prevalent metabolic disorder. Currently, there are no effective pharmacotherapeutic options for preventing and treating NASH. Portulaca oleracea L. (POL) is an edible herb that has been used for preventing and treating some metabolic disorders in China, but the bioactive constituents in POL and the related mechanisms for treating NASH are still unclear. Here, a comprehensive research strategy was used to identify the core genes and the key constituents in POL for treating NASH, via integrating bioinformatics analysis and experimental pharmacology both in vitro and in vivo. The phenotypes and mechanisms of POL were carefully investigated by performing a set of in vivo and in vitro experiments. Bioinformatics analysis suggested that prostaglandin-endoperoxide synthase 2 (PTGS2) was the core target and myricetin (Myr) was the key constituent in POL for treating NASH. In NASH mice model induced by methionine choline deficiency diet, POL significantly alleviated hepatic steatosis and liver injury. In free fatty acids-induced hepatocytes, POL and Myr significantly down-regulated the expression of PTGS2, decreased the number of lipid droplets, and regulated the mRNA expression of lipid synthesis and homeostasis genes, including FASN, CPT1a, SERBP1c, ACC1, and SCD1. In lipopolysaccharide-induced macrophages, POL and Myr significantly reduced the expression of PTGS2 and blocked the secretion of inflammatory mediators TNF-α, IL-6, and IL-1ß. Further investigations demonstrate that Myr acts as both suppressor and inhibitor of PTGS2. Collectively, POL and its major component Myr can ameliorate NASH via down-regulating and inhibiting PTGS2, suggesting that POL and Myr can be developed as novel medicines for treating NASH.

Targeting COX-2 potently inhibits proliferation of cancer cells in vivo but not in vitro in cutaneous squamous cell carcinoma.

BACKGROUND: Cyclooxygenase 2 (COX-2) is an inducible enzyme which promotes tumorigenesis in many types of cancers. Genetic knockout of COX-2 significantly suppresses the tumorigenesis of skin squamous cell carcinoma (SCC). However, COX-2 inhibitor treatment only showed mild to moderate inhibition on SCC in previous reports. The aim of this study is to solve this contradiction and to re-evaluate the therapeutic potential of targeting COX-2 in SCC. METHODS: COX-2 was knocked down by shRNA in two different SCC cell lines, A431 and SCC-13. The cells proliferation and migration capacity were evaluated by cell growth curves and monolayer scratch assay, respectively. Cancer cells with COX-2 knockdown were also xenografted into Balb/c nude mice and tumor growth curves were recorded over time. In addition, we changed the drug administration route and intraperitoneally injected COX-2 inhibitor celecoxib into mice to evaluate its anti-cancer activity. RESULTS: Knockdown of COX-2 exhibited mild or even no effect on cell proliferation and migration in two different SCC cell lines in vitro. However, when cancer cells were xenografted into nude mice, knockdown of COX-2 significantly suppressed proliferation of cancer cells in tumors. At last, intraperitoneal injection instead of oral administration of COX-2 inhibitor celecoxib potently suppressed tumor growth. CONCLUSIONS: Our results indicate that COX-2 might impact on the interaction between cancer cells and surrounding microenvironments rather than on cancer cells directly, and demonstrate that targeting COX-2 is a very promising therapeutic approach for SCC treatment.