ABSTRACT
Trilobolide and its analogues belong to the guaianolide type of sesquiterpene lactones, which are characteristic and widely distributed within the families Asteraceae and Apiaceae. Certain guaianolides are receiving continuously increasing attention for their promising sarco-endoplasmic reticulum Ca2+-ATPase (SERCA)-inhibitory activity. However, because of their alkylation capabilities, they are generally toxic. Therefore, the search for compounds with significant immunobiological properties but with decreased cytotoxicities suitable for use in immune-based pharmacotherapy is ongoing. Therefore, we extended our previous investigation of the immunobiological effects of trilobolide to a series of structurally related guaianolides and germacranolides. To evaluate the relationship, we tested a series of selected derivatives containing α-methyl lactone or exomethylene lactone ring. For a wider comparison, we also included some of their glycosidic derivatives. We assessed the in vitro immunobiological effects of the tested compounds on nitric oxide (NO) production, cytokine secretion, and prostaglandin E2 (PGE2) release by mouse peritoneal cells, activated primarily by lipopolysaccharide (LPS), and evaluated their viability. The inhibitory effects of the apparently most active substance, 8-deoxylactucin, seem to be the most promising.
Subject(s)
Lactones , Nitric Oxide , Sesquiterpenes, Germacrane , Sesquiterpenes, Guaiane , Animals , Nitric Oxide/metabolism , Mice , Sesquiterpenes, Germacrane/pharmacology , Sesquiterpenes, Germacrane/chemistry , Sesquiterpenes, Guaiane/pharmacology , Sesquiterpenes, Guaiane/chemistry , Lactones/pharmacology , Lactones/chemistry , Lipopolysaccharides/pharmacology , Sesquiterpenes/pharmacology , Sesquiterpenes/chemistry , Cytokines/metabolism , Dinoprostone/metabolism , Dinoprostone/biosynthesis , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/metabolism , Butyrates , FuransABSTRACT
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-1ß (IL-1ß). The dominant effect of IL-1ß 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-1ß 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.
Subject(s)
Macrophages , Oxylipins , Pyroptosis , Secretome , Wound Healing , Animals , Female , Humans , Mice , Caspase 1/metabolism , Cell Movement , Cell Proliferation , Cyclooxygenase 2/metabolism , Dinoprostone/biosynthesis , Dinoprostone/metabolism , Fibroblasts/metabolism , Fibroblasts/cytology , Gasdermins/metabolism , Inflammasomes/metabolism , Interleukin-1beta , Lipidomics , Macrophages/metabolism , Macrophages/cytology , Mice, Inbred C57BL , Oxylipins/metabolism , Phosphate-Binding Proteins/metabolism , Secretome/metabolism , Wound Healing/physiologyABSTRACT
BACKGROUND: Phobic anxiety present after stroke (called poststroke anxiety, PSA) can hamper the rehabilitation of patients and disrupt their usual activities. Besides, the symptoms and mechanisms of PSA are different from those in nonstroke populations that have generalized anxiety disorder. What's more, the treatment approaches for phobic anxiety are confined to unitary or general methods with poor efficiency. METHODS: Behavioural test screen combined bioinformatics analysis explored molecular changes between generalized anxiety disorder in nonstroke mice (restraint stress, RS) and photothrombotic stroke mice exposed to environmental stress (PTS + RS, mimicking PSA). Multiple molecular biological and neurobiological methods were employed to explain mechanisms in vitro and in vivo. And exploiting gamma flicker stimulation device for therapy. RESULTS: Microglial (MG) overactivation is a prominent characteristic of PTS + RS. HDAC3 was mainly upregulated in activated-microglia from damaged cortex and that local prostaglandin E2 (PGE2) production increased in MG via HDAC3-mediated activation of NF-κB signalling by p65 deacetylation. A high content of PGE2 in damaged ischaemic cortex could diffuse freely to amygdala, eliciting anxiety susceptibility of PSA via EP2. Importantly, gamma flicker stimulation relieved anxious behaviour of PTS + RS by modulating the HDAC3/Cox1/EP2 network at some extent. CONCLUSIONS: HDAC3-regulated PGE2 production by microglia constitutes phobic anxiety susceptibility after stroke and a protective approach of gamma visual stimulation can be a candidate new therapy.
Subject(s)
Anxiety , Dinoprostone , Histone Deacetylases , Microglia , Stroke , Animals , Anxiety Disorders , Dinoprostone/biosynthesis , Histone Deacetylases/metabolism , Humans , Male , Mice , Microglia/metabolism , Photic Stimulation , Prostate-Specific Antigen , Stroke/therapyABSTRACT
Porphyromonas gingivalis is commonly known as one of the major pathogens contributing to periodontitis, and its persistent infection may increase the risk for the disease. The proinflammatory mediators, including IL-6, TNF-α, and cyclooxygenase-2 (COX-2)/PGE2, are closely associated with progression of periodontitis. In this study, we focused on the cysteine protease "gingipains," lysine-specific gingipain, arginine-specific gingipain (Rgp) A, and RgpB, produced by P. gingivalis, and used the wild-type strain and several gene-deletion mutants (rgpA, rgpB, kgp, and fimA) to elucidate the involvement of gingipains in COX-2 expression and PGE2 production. We infected human monocytes, which are THP-1 cells and primary monocytes, with these bacterial strains and found that gingipains were involved in induction of COX-2 expression and PGE2 production. We have shown that the protease activity of gingipains was crucial for these events by using gingipain inhibitors. Furthermore, activation of ERK1/2 and IκB kinase was required for gingipain-induced COX-2 expression/PGE2 production, and these kinases activated two transcription factors, c-Jun/c-Fos (AP-1) and NF-κB p65, respectively. In particular, these data suggest that gingipain-induced c-Fos expression via ERK is essential for AP-1 formation with c-Jun, and activation of AP-1 and NF-κB p65 plays a central role in COX-2 expression/PGE2 production. Thus, we show the (to our knowledge) novel finding that gingipains with the protease activity from P. gingivalis induce COX-2 expression and PGE2 production via activation of MEK/ERK/AP-1 and IκB kinase/NF-κB p65 in human monocytes. Hence it is likely that gingipains closely contribute to the inflammation of periodontal tissues.
Subject(s)
Cyclooxygenase 2/biosynthesis , Dinoprostone/biosynthesis , Gingipain Cysteine Endopeptidases/metabolism , MAP Kinase Signaling System/physiology , Periodontitis/pathology , Porphyromonas gingivalis/metabolism , Bacterial Proteins/genetics , Cell Line , Cysteine Endopeptidases/genetics , Fimbriae Proteins/genetics , Gingipain Cysteine Endopeptidases/genetics , Humans , I-kappa B Kinase/metabolism , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Monocytes/microbiology , Periodontitis/microbiology , THP-1 Cells , Transcription Factor AP-1/metabolism , Transcription Factor RelA/metabolismABSTRACT
Toll-like receptors (TLRs) are pattern recognition receptors that play a critical role in innate immune diseases. TLR3, which is localized in the endosomal compartments of hematopoietic immune cells, is able to recognize double-stranded RNA (dsRNA) derived from viruses and bacteria and thereby induce innate immune responses. Inflammatory periodontal bone resorption is caused by bacterial infections, which initially is regulated by innate immunity; however, the roles of TLR3 signaling in bone resorption are still not known. We examined the roles of TLR3 signaling in bone resorption using poly(I:C), a synthetic dsRNA analog. In cocultures of mouse bone marrow cells and stromal osteoblasts, poly(I:C) clearly induced osteoclast differentiation. In osteoblasts, poly(I:C) increased PGE2 production and upregulated the mRNA expression of PGE2-related genes, Ptgs2 and Ptges, as well as that of a gene related to osteoclast differentiation, Tnfsf11. In addition, we found that indomethacin (a COX-2 inhibitor) or an antagonist of the PGE2 receptor EP4 attenuated the poly(I:C)-induced PGE2 production and subsequent Tnfsf11 expression. Poly(I:C) also prolonged the survival of the mature osteoclasts associated with the increased mRNA expression of osteoclast marker genes, Nfatc1 and Ctsk. In ex vivo organ cultures of periodontal alveolar bone, poly(I:C) induced bone-resorbing activity in a dose-dependent manner, which was attenuated by the simultaneous administration of either indomethacin or an EP4 antagonist. These data suggest that TLR3 signaling in osteoblasts controls PGE2 production and induces the subsequent differentiation and survival of mature osteoclasts. Endogenous TLR3 in stromal osteoblasts and osteoclasts synergistically induces inflammatory alveolar bone resorption in periodontitis.
Subject(s)
Bone Resorption , Dinoprostone , Osteoblasts , Toll-Like Receptor 3 , Animals , Bone Resorption/genetics , Bone Resorption/metabolism , Cells, Cultured , Dinoprostone/biosynthesis , Dinoprostone/genetics , Dinoprostone/metabolism , Endosomes/metabolism , Indomethacin/pharmacology , Mice , Osteoblasts/metabolism , Osteoclasts/metabolism , Prostaglandins E/adverse effects , Prostaglandins E/metabolism , RANK Ligand/metabolism , RNA, Messenger/metabolism , Toll-Like Receptor 3/genetics , Toll-Like Receptor 3/metabolismABSTRACT
MicroRNAs are small non-coding RNA regulatory molecules that play an important role in the development and function of immune cells. MicroRNA-26a (miR-26a) exhibits anti-inflammatory immune effects on immune cells. However, the exact mechanism by which miR-26a plays an anti-inflammatory role remains unclear. Here, we report that miR-26a reduces inflammatory response via inhibition of prostaglandin E2 (PGE2) production by targeting cyclooxygenase-2 (COX-2). We found that miR-26a was downregulated in vitro and in vivo. The miR-26a mimic significantly decreased COX-2 protein levels, further inhibiting pro-inflammatory cytokine production in LPS-stimulated macrophages. We predicted that miR-26a could potentially target COX-2 in LPS-stimulated macrophages. Computational algorithms showed that the 3'-UTR of COX-2 mRNA contains a binding site for miR-26a. This putative targeting relationship between miR-26a and COX-2 was further confirmed by a dual-reporter gene assay. The anti-inflammatory effects of the miR-26a mimic were diminished by PGE2 supplementation. Importantly, miR-26a mimics protected mice from lethal endotoxic shock and attenuated pro-inflammatory cytokine production. Collectively, these results suggest that miR-26a may function as a novel feedback negative regulator of the hyperinflammatory response and as a drug target for the progression of inflammation.
Subject(s)
Cyclooxygenase 2 , Dinoprostone , MicroRNAs , 3' Untranslated Regions , Animals , Cyclooxygenase 2/genetics , Cyclooxygenase 2/metabolism , Cytokines/genetics , Dinoprostone/biosynthesis , Inflammation , Lipopolysaccharides , Mice , MicroRNAs/geneticsABSTRACT
Flavonols possess several beneficial bioactivities in vitro and in vivo. In this study, two flavonols galangin and quercetin with or without heat treatment (100 °C for 15-30 min) were assessed for their anti-inflammatory activities in lipopolysaccharide (LPS)-stimulated rat intestinal epithelial (IEC-6) cells and whether the heat treatment caused activity changes. The flavonol dosages of 2.5-20 µmol/L had no cytotoxicity on the cells but could enhance cell viability (especially using 5 µmol/L flavonol dosage). The flavonols could decrease the production of prostaglandin E2 and three pro-inflammatory cytokines interleukin-1ß (IL-1ß), IL-6, and tumor necrosis factor-α, and simultaneously promote the production of two anti-inflammatory cytokines IL-10 and transforming growth factor-ß. The Western-blot results verified that the flavonols could suppress the LPS-induced expression of TLR4 and phosphorylated IκBα and p65, while the molecular docking results also illustrated that the flavonols could bind with TLR4 and NF-κB to yield energy decreases of -(21.9-28.6) kJ/mol. Furthermore, an inhibitor BAY 11-7082 blocked the NF-κB signaling pathway by inhibiting the expression of phosphorylated IκBα/p65 and thus mediated the production of IL-6/IL-10 as the flavonols did, which confirmed the assessed anti-inflammatory effect of the flavonols. Consistently, galangin had higher anti-inflammatory activity than quercetin, while the heated flavonols (especially those with longer heat time) were less active than the unheated counterparts to exert these target anti-inflammatory effects. It is highlighted that the flavonols could antagonize the LPS-caused IEC-6 cells inflammation via suppressing TLR4/NF-κB activation, but heat treatment of the flavonols led to reduced anti-inflammatory efficacy.
Subject(s)
Anti-Inflammatory Agents/pharmacology , Epithelial Cells/drug effects , Flavonoids/pharmacology , Hot Temperature , Intestinal Mucosa/drug effects , Quercetin/pharmacology , Animals , Anti-Inflammatory Agents/chemistry , Cell Line , Cell Survival/drug effects , Cytokines/antagonists & inhibitors , Cytokines/biosynthesis , Dinoprostone/antagonists & inhibitors , Dinoprostone/biosynthesis , Epithelial Cells/metabolism , Flavonoids/chemistry , Inflammation/drug therapy , Inflammation/metabolism , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Molecular Docking Simulation , Molecular Structure , NF-kappa B/antagonists & inhibitors , NF-kappa B/metabolism , Quercetin/chemistry , Rats , Signal Transduction/drug effects , Toll-Like Receptor 4/antagonists & inhibitors , Toll-Like Receptor 4/metabolismABSTRACT
A series of thirteen triarylpyrazole analogs were investigated as inhibitors of lipopolysaccharide (LPS)-induced prostaglandin E2 (PGE2) and nitric oxide (NO) production in RAW 264.7 macrophages. The target compounds 1a-m have first been assessed for cytotoxicity against RAW 264.7 macrophages to determine their non-cytotoxic concentration(s) for anti-inflammatory testing to make sure that the inhibition of PGE2 and NO production would not be caused by cytotoxicity. It was found that compounds 1f and 1m were the most potent PGE2 inhibitors with IC50 values of 7.1 and 1.1 µM, respectively. In addition, these compounds also showed inhibitory effects of 11.6% and 37.19% on LPS-induced NO production, respectively. The western blots analysis of COX-2 and iNOS showed that the PGE2 and NO inhibitory effect of compound 1m are attributed to inhibition of COX-2 and iNOS protein expression through inactivation of p38.
Subject(s)
Anti-Inflammatory Agents/pharmacology , Dinoprostone/biosynthesis , Macrophages/drug effects , Macrophages/metabolism , Nitric Oxide/biosynthesis , Pyrazoles/pharmacology , Animals , Anti-Inflammatory Agents/chemistry , Dose-Response Relationship, Drug , Lipopolysaccharides/immunology , Macrophages/immunology , Mice , Molecular Structure , Pyrazoles/chemistry , RAW 264.7 Cells , Structure-Activity RelationshipABSTRACT
Prostaglandin E2 (PGE2) plays pivotal roles in controlling microglial activation with the EP2 receptor, a PGE2 receptor subtype. Activated microglia are often reported to increase cyclooxygenase (COX)-2 expression, followed by PGE2 production, but it is unclear whether extracellular PGE2 is involved in microglial PGE2 synthesis. In the present study, we report that PGE2 increases COX-2 protein in microglia. In a culture system, PGE2 at 10-6 M for 3 h increased COX-2 and microsomal PGE synthase (mPGES)-1 mRNA levels, and reduced mPGES-2, but did not affect COX-1 or cytosolic PGE synthase (cPGES) in microglia. PGE2 at 10-6 M for 3 h also increased the COX-2 protein level, but did not affect COX-1, mPGES-1, mPGES-2, or cPGES. An EP2 agonist, ONO-AE1-259-01, also increased COX-2 and mPGES-1 mRNA levels, and reduced mPGES-2, but did not affect COX-1 or cPGES, whereas an EP1 agonist, ONO-DI-004, an EP3 agonist, ONO-AE-248, and an EP4 agonist, ONO-AE1-329, had no effect. Similar to PGE2, ONO-AE1-259-01 increased the COX-2 protein level, but did not affect COX-1, mPGES-1, mPGES-2, or cPGES. In addition, the effects of PGE2 were inhibited by an EP2 antagonist, PF-04418948, but not by an EP1 antagonist, ONO-8713, an EP3 antagonist, ONO-AE3-240, or an EP4 antagonist, ONO-AE3-208, at 10-6 M. On the other hand, lipopolysaccharide (LPS) increased PGE2 production, but the LPS-induced PGE2 production was not affected by ONO-8713, PF-04418948, ONO-AE3-240, or ONO-AE3-208. These results indicate that PGE2 increases COX-2 protein in microglia through the EP2 receptor supporting the idea that extracellular PGE2 has a triggering aspect for microglial activation.
Subject(s)
Cyclooxygenase 2/biosynthesis , Dinoprostone/pharmacology , Microglia/drug effects , Animals , Azetidines/pharmacology , Cells, Cultured , Cerebral Cortex/cytology , Cyclooxygenase 1/biosynthesis , Cyclooxygenase 1/genetics , Cyclooxygenase 2/genetics , Dinoprostone/analogs & derivatives , Dinoprostone/biosynthesis , Enzyme Induction/drug effects , Membrane Proteins/biosynthesis , Membrane Proteins/genetics , Methyl Ethers/pharmacology , Microglia/enzymology , Microsomes/drug effects , Microsomes/enzymology , Prostaglandin-E Synthases/biosynthesis , Prostaglandin-E Synthases/genetics , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Rats , Rats, Wistar , Receptors, Prostaglandin E, EP2 Subtype/agonists , Receptors, Prostaglandin E, EP2 Subtype/antagonists & inhibitorsABSTRACT
A series of halogenated 1,5-diarylimidazole compounds were synthesized and their inhibitory effects on LPS-induced PGE2 production in RAW 264.7 cells were evaluated. A wide variety of 2,4-, 4-, and 2-halogenated 5-aryl-1-(4-methylsulfonylphenyl)imidazoles were synthesized for SAR study via two different pathways. Overall, 4-halogenated 5-aryl-1-(4-methylsulfonylphenyl)imidazoles, regardless of the species of halogen, exhibited very strong inhibitory activities of PGE2 production. Among them, 4-chloro-5-(4-methoxyphenyl)-1-(4-methylsulfonylphenyl)imidazole (3, IC50 3.3 nM ± 2.93), and 4-chloro-5-(4-chlorophenyl)-1-(4-methylsulfonylphenyl)imidazole (13, IC50 5.3 nM ± 0.23) showed the best results.
Subject(s)
Dinoprostone/biosynthesis , Imidazoles , RAW 264.7 Cells/drug effects , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemical synthesis , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Halogenation , Imidazoles/chemical synthesis , Imidazoles/pharmacology , Mice , Molecular Structure , Structure-Activity RelationshipABSTRACT
Listeria monocytogenes is an intracellular bacterium that elicits robust CD8+ T-cell responses. Despite the ongoing development of L. monocytogenes-based platforms as cancer vaccines, our understanding of how L. monocytogenes drives robust CD8+ T-cell responses remains incomplete. One overarching hypothesis is that activation of cytosolic innate pathways is critical for immunity, as strains of L. monocytogenes that are unable to access the cytosol fail to elicit robust CD8+ T-cell responses and in fact inhibit optimal T-cell priming. Counterintuitively, however, activation of known cytosolic pathways, such as the inflammasome and type I IFN, lead to impaired immunity. Conversely, production of prostaglandin E2 (PGE2) downstream of cyclooxygenase-2 (COX-2) is essential for optimal L. monocytogenes T-cell priming. Here, we demonstrate that vacuole-constrained L. monocytogenes elicit reduced PGE2 production compared to wild-type strains in macrophages and dendritic cells ex vivo. In vivo, infection with wild-type L. monocytogenes leads to 10-fold increases in PGE2 production early during infection whereas vacuole-constrained strains fail to induce PGE2 over mock-immunized controls. Mice deficient in COX-2 specifically in Lyz2+ or CD11c+ cells produce less PGE2, suggesting these cell subsets contribute to PGE2 levels in vivo, while depletion of phagocytes with clodronate abolishes PGE2 production completely. Taken together, this work demonstrates that optimal PGE2 production by phagocytes depends on L. monocytogenes access to the cytosol, suggesting that one reason cytosolic access is required to prime CD8+ T-cell responses may be to facilitate production of PGE2.
Subject(s)
Dendritic Cells/immunology , Dinoprostone/biosynthesis , Dinoprostone/immunology , Listeriosis/immunology , Macrophages/immunology , Animals , Dendritic Cells/metabolism , Dendritic Cells/microbiology , Female , Listeria monocytogenes/immunology , Lymphocyte Activation/immunology , Macrophages/metabolism , Macrophages/microbiology , Male , Mice , Mice, Inbred C57BLABSTRACT
Recently, adipose-derived stem cells (ADSCs) are considered to be ideal for application in cell therapy or tissue regeneration, mainly due to their wide availability and easy access. In this study, we examined the anti-inflammatory effects of membrane-free stem cell extract (MFSC-Ex) derived from ADSCs against lipopolysaccharide (LPS)/interferon-gamma (IFN-γ) on RAW 264.7 macrophage cells. Exposure of RAW macrophages to LPS and IFN-γ stimuli induced high levels of nitric oxide (NO), cyclooxygenase-2 (COX-2), and prostaglandin E2 (PGE2) production. However, pretreatment with MFSC-Ex inhibited LPS/IFN-γ-induced these pro-inflammatory mediators. To clarify the molecular mechanisms underlying the anti-inflammatory property of MFSC-Ex, we analyzed nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) protein expressions by Western blotting. Our study showed that treatment of MFSC-Ex significantly down-regulated inducible nitric oxide synthase (iNOS) and COX-2 protein expressions. Furthermore, phosphorylation of extracellular signal-regulated kinase (ERK) and p38 was also blocked by treatment with MFSC-Ex, indicating that inhibitory effect of MFSC-Ex on MAPK signaling cascade may attribute to inactivation of NF-κB. From these findings, we suggest that MFSC-Ex exert anti-inflammatory activities, which suppressed LPS/IFN-γ-induced production of NO, COX-2 and PGE2 by regulation of NF-κB and MAPK signaling pathway in RAW 264.7 macrophages. In conclusion, MFSC-Ex might provide a new therapeutic opportunity to treatment of inflammatory-related diseases.
Subject(s)
Adipose Tissue/cytology , Anti-Inflammatory Agents/pharmacology , Interferon-gamma/pharmacology , Lipopolysaccharides/pharmacology , Macrophages/drug effects , Protective Agents/pharmacology , Stem Cells/metabolism , Animals , Anti-Inflammatory Agents/chemistry , Cell Survival/drug effects , Cyclooxygenase 2/biosynthesis , Dinoprostone/biosynthesis , Lipopolysaccharides/immunology , Macrophages/immunology , Mice , Models, Biological , Protective Agents/metabolism , RAW 264.7 CellsABSTRACT
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief. A reader reported that Figure 9 of the above paper contains similar section with Figure 4 of another article authored by the same group in Inflammopharmacology, 29, (2021) 1119-1129, https://doi.org/10.1007/s10787-021-00840-9, and part of the Figure 9 of the above paper is used in Figure 9 of another article authored by the same group in Inflammopharmacology, 29, (2021) 673682, https://doi.org/10.1007/s10787-021-00804-z. The journal requested the authors to explain the repeated use of the image and provide the raw data. However, the authors were not able to fulfill this request and therefore the Editor-in-Chief has decided to retract the article.
Subject(s)
Arthritis, Rheumatoid/metabolism , Dinoprostone/biosynthesis , Ephedrine/pharmacology , Gene Expression Regulation/drug effects , Interleukin-1beta/biosynthesis , Interleukin-6/biosynthesis , Tumor Necrosis Factor-alpha/biosynthesis , Animals , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/pathology , Male , Rats , Rats, Sprague-DawleyABSTRACT
As a potent autocrine regulator, the proinflammatory cytokine interleukin 6 (IL6) is expressed in granulosa cells and is involved in the modulation of various follicular functions, including follicular development and ovulation. At present, the detailed molecular mechanisms by which IL6 regulates the event of ovulation remain to be elucidated. In the present study, primary and immortalized (SVOG) human granulosa-lutein (hGL) cells were used to investigate the effects of IL6 on the expression of prostaglandin-endoperoxide synthase 2 (PTGS2) and the subsequent synthesis of prostaglandin E2 (PGE2) and to investigate the underlying molecular mechanisms. We found that instead of classic signaling, IL6/soluble form of the IL6 receptor (sIL-6Ralpha) trans-signaling induced the expression of PTGS2 and production of PGE2 in both SVOG cells and primary hGL cells. Moreover, IL6/sIL-6Ralpha activated the phosphorylation of Janus-activated kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3), which in turn induced STAT3 nuclear translocation. In addition, these effects were suppressed by the addition of inhibitors (AG490 for JAK2 and C188-9 for STAT3) and by the small interfering RNA-mediated knockdown of STAT3. In addition, suppressor of cytokine signaling 3 (SOCS3) acts as a negative-feedback regulator in IL6/sIL-6Ralpha-induced cellular activities, including the activation and nuclear translocation of STAT3, upregulation of PTGS2 expression, and increase in PGE2 production in SVOG cells. In conclusion, IL6 trans-signaling upregulates the expression of PTGS2 and increases the production of PGE2 via the JAK2/STAT3/SOCS3 signaling pathway in hGL cells. Our findings provide insights into the molecular mechanisms by which IL6 trans-signaling may potentially modulate the event of ovulation in human ovaries.
Subject(s)
Cyclooxygenase 2/genetics , Dinoprostone/biosynthesis , Interleukin-6/genetics , Luteal Cells/metabolism , Receptors, Interleukin-6/metabolism , Signal Transduction , Cyclooxygenase 2/metabolism , Female , Gene Expression , Granulosa Cells/metabolism , Humans , Interleukin-6/metabolismABSTRACT
2-Arachidonyl-lysophosphatidylethanolamine, shortly 2-ARA-LPE, is a polyunsaturated lysophosphatidylethanolamine. 2-ARA-LPE has a very long chain arachidonic acid, formed by an ester bond at the sn-2 position. It has been reported that 2-ARA-LPE has anti-inflammatory effects in a zymosan-induced peritonitis model. However, it's action mechanisms are poorly investigated. Recently, resolution of inflammation is considered to be an active process driven by M2 polarized macrophages. Therefore, we have investigated whether 2-ARA-LPE acts on macrophages for anti-inflammation, whether 2-ARA-LPE modulates macrophage phenotypes to reduce inflammation, and whether 2-ARA-LPE is anti-inflammatory in a carrageenan-induced paw edema model. In mouse peritoneal macrophages, 2-ARA-LPE was found to inhibit lipopolysaccharide (LPS)-induced M1 macrophage polarization, but not induce M2 polarization. 2-ARA-LPE inhibited the inductions of inducible nitric oxide synthase and cyclooxygenase-2 in mouse peritoneal macrophages at the mRNA and protein levels. Furthermore, products of the two genes, nitric oxide and prostaglandin E2, were also inhibited by 2-ARA-LPE. However, 1-oleoyl-LPE did not show any activity on the macrophage polarization and inflammatory responses. The anti-inflammatory activity of 2-ARA-LPE was also verified in vivo in a carrageenan-induced paw edema model. 2-ARA-LPE inhibits LPS-induced M1 polarization, which contributes to anti-inflammation and suppresses the carrageenan-induced paw edema in vivo.
Subject(s)
Anti-Inflammatory Agents/pharmacology , Arachidonic Acids/pharmacology , Edema/drug therapy , Lysophospholipids/pharmacology , Macrophages, Peritoneal/drug effects , Animals , Anti-Inflammatory Agents/chemistry , Arachidonic Acids/chemistry , Carrageenan/administration & dosage , Cyclooxygenase 2/immunology , Dinoprostone/antagonists & inhibitors , Dinoprostone/biosynthesis , Edema/chemically induced , Edema/immunology , Edema/pathology , Hindlimb/drug effects , Hindlimb/immunology , Hindlimb/metabolism , Interleukin-12 Subunit p35/antagonists & inhibitors , Interleukin-12 Subunit p35/immunology , Interleukin-1beta/antagonists & inhibitors , Interleukin-1beta/immunology , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Lysophospholipids/chemistry , Macrophages, Peritoneal/immunology , Male , Mice , Mice, Inbred C57BL , Nitric Oxide/antagonists & inhibitors , Nitric Oxide/biosynthesis , Nitric Oxide Synthase Type II/antagonists & inhibitors , Nitric Oxide Synthase Type II/immunology , Primary Cell Culture , Treatment OutcomeABSTRACT
Bovine endometrium infection with gram-negative bacteria commonly causes uterine diseases. Previous studies indicate that prostaglandin E2 (PGE2) is an inflammatory mediator in bacterial endometritis. However, the mechanism underlying lipopolysaccharide (LPS)-induced inflammatory response regulation in bovine endometrial explants remains elusive. In the present study, bovine explants were pre-treated with 15-hydroxyprostaglandin dehydrogenase (15-PGDH) inhibitors before LPS stimulation. PGE2 secretion, prostaglandin synthetase, pro-inflammatory factor, damage-associated molecular pattern (DAMP), and related signaling pathway factor levels were evaluated. Using 15-PGDH inhibitors pre-treatment, LPS-treated bovine endometrial explants exhibited augmentation of PGE2 and DAMP expression, and upregulation of various signaling pathway factors. Protein kinase A (PKA), extracellular-signal-regulated kinase, and c-Jun N-terminal kinase phosphorylation and degradation of nuclear transcription factor-κB (NF-κB) inhibitors were induced in the pre-treated endometrial explants. The mechanism underlying LPS-induced PGE2 accumulation acting as a pro-inflammatory mediator through toll-like receptor 4 signaling in bovine explants could involve the PKA, mitogen-activated protein kinase, and NF-κB pathways.
Subject(s)
Dinoprostone/biosynthesis , Endometritis/drug therapy , Endometrium/drug effects , Inflammation/drug therapy , Lipopolysaccharides/pharmacology , NF-kappa B/metabolism , Toll-Like Receptor 4/metabolism , Animals , Cattle , Dinoprostone/metabolism , Endometritis/metabolism , Endometritis/microbiology , Endometritis/pathology , Endometrium/metabolism , Endometrium/pathology , Female , Inflammation/metabolism , Inflammation/microbiology , Inflammation/pathology , Signal TransductionABSTRACT
Acetaminophen is one of the most widely used analgesic and antipyretic medicines, whose long-period use has reportedly been associated with an increased risk of bone fracture. However, the mechanism underlying this undesired effect remains to be investigated. The homeostatic control of bone tissue depends on the interaction between osteoblasts and osteoclasts. Osteoprotegerin produced by osteoblasts is known to play an essential role in suppressing osteoclast induction. We have previously reported that prostaglandin (PG) E2 and PGF2α induce osteoprotegerin synthesis through p38 mitogen-activated protein kinase (MAPK), p44/p42 MAPK and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) in osteoblast-like MC3T3-E1 cells. In the present study, we investigated the effects of acetaminophen on the osteoprotegerin synthesis induced by PGE2 and PGF2α in MC3T3-E1 cells. Acetaminophen significantly suppressed the osteoprotegerin release stimulated by PGE2 and PGF2α. The PGE2-induced expression of osteoprotegerin mRNA was also reduced by acetaminophen. Acetaminophen markedly downregulated the phosphorylation of SAPK/JNK stimulated by PGE2 and PGF2α, but not those of p38 MAPK or p44/p42 MAPK. SP600125, an inhibitor of SAPK/JNK, suppressed the levels of PGE2- and PGF2α-upregulated osteoprotegerin mRNA expression. Taken together, these results strongly suggest that acetaminophen reduces the PGE2- and PGF2α-stimulated synthesis of osteoprotegerin in osteoblasts, and that the suppressive effect is exerted via attenuation of SAPK/JNK. These findings provide a molecular basis for the possible effect of acetaminophen on bone tissue metabolism.
Subject(s)
Acetaminophen/pharmacology , Dinoprost/biosynthesis , Dinoprostone/biosynthesis , MAP Kinase Kinase 4/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Osteoblasts/drug effects , Osteoblasts/metabolism , Osteoprotegerin/biosynthesis , p38 Mitogen-Activated Protein Kinases/metabolism , 3T3 Cells , Animals , Anthracenes , Bone Remodeling , Bone and Bones/drug effects , Densitometry , Down-Regulation , Mice , PhosphorylationABSTRACT
Components of the iron reductive pathway of Candida albicans have been implicated in the production of prostaglandin E2 (PGE2) and virulence. However, it is unknown whether other components of this pathway influence PGE2. We investigated the role of the iron reductive pathway of C. albicans in biofilm formation, PGE2 production, and virulence in Caenorhabditis elegans. Additionally, as the co-occurrence of C. albicans and Pseudomonas aeruginosa in host tissues is frequent and involves competition for host-associated iron, we examined the effects of this interaction. Deletion of multicopper oxidase gene, FET99, and iron permease genes, FTH1 and FTH2, affected biofilm metabolic activity, and for the FTH2 mutant, also biofilm morphology. Deletion of CCC1 (vacuolar iron transporter) and CCC2 (P-type ATPase copper importer) also influenced biofilm morphology. For PGE2 production, deletion of FET99, FTH1, FTH2, CCC1, and CCC2 caused a significant reduction by monomicrobial biofilms, while FTH2deletion caused the highest reduction in polymicrobial biofilms. URA3 positive mutants of FET99 and FTH2 demonstrated attenuated virulence in C. elegans, potentially due to the inability of mutants to form hyphae in vivo. Deductively, the role of the iron reductive pathway in PGE2 synthesis is indirect, possibly due to their role in iron homeostasis. LAY SUMMARY: Iron uptake is vital for disease-causing microbes like Candida albicans. Using strains deficient in some iron-uptake genes, we show that iron-uptake genes, especially FET99 and FTH2, play a role in biofilm formation, prostaglandin production, and virulence in the nematode infection model.
Subject(s)
Biofilms/drug effects , Caenorhabditis elegans/metabolism , Caenorhabditis elegans/parasitology , Candida albicans/metabolism , Dinoprostone/biosynthesis , Iron/metabolism , Pseudomonas aeruginosa/metabolism , Virulence/drug effects , Animals , Candida albicans/genetics , Candida albicans/pathogenicity , Dinoprostone/genetics , Genetic Variation , Genotype , Host-Pathogen Interactions/genetics , Metabolic Networks and Pathways/genetics , Pseudomonas aeruginosa/genetics , Pseudomonas aeruginosa/pathogenicity , Virulence/geneticsABSTRACT
Prostaglandin E2 (PGE2) is a key mediator of inflammation, and consequently huge efforts have been devoted to the development of novel agents able to regulate its formation. In this work, we present the synthesis of various α-ketoheterocycles and a study of their ability to inhibit the formation of PGE2 at a cellular level. A series of α-ketobenzothiazoles, α-ketobenzoxazoles, α-ketobenzimidazoles, and α-keto-1,2,4-oxadiazoles were synthesized and chemically characterized. Evaluation of their ability to suppress the generation of PGE2 in interleukin-1ß plus forskolin-stimulated mesangial cells led to the identification of one α-ketobenzothiazole (GK181) and one α-ketobenzoxazole (GK491), which are able to suppress the PGE2 generation at a nanomolar level.
Subject(s)
Dinoprostone/antagonists & inhibitors , Glomerular Mesangium/drug effects , Heterocyclic Compounds/pharmacology , Prostaglandin Antagonists/pharmacology , Animals , Cells, Cultured , Dinoprostone/biosynthesis , Glomerular Mesangium/cytology , Glomerular Mesangium/metabolism , Molecular Docking Simulation , Rats , Spectrum Analysis/methodsABSTRACT
Prostaglandin G/H synthase 2 (PTGS2) is a rate-limiting enzyme in prostaglandin synthesis. The present study assessed the role of the uterine circadian clock on Ptgs2 transcription in response to steroid hormones during early pregnancy. We demonstrated that the core clock genes (Bmal1, Per2, Nr1d1, and Dbp), Vegf, and Ptgs2, and their encoded proteins, have rhythmic expression in the mouse uterus from days 3.5 to 4.5 (D3.5-4.5) of pregnancy. Progesterone (P4) treatment of cultured uterus endometrial stromal cells (UESCs) isolated from mPer2Luciferase reporter gene knock-in mice on D4 induced a phase shift in PER2::LUCIFERASE oscillations. This P4-induced phase shift of PER2::LUCIFERASE oscillations was significantly attenuated by the P4 antagonist RU486. Additionally, the amplitude of PER2::LUCIFERASE oscillations was increased by estradiol (E2) treatment in the presence of P4. Consistently, the mRNA levels of clock genes (Bmal1 and Per2), Vegf, and Ptgs2 were markedly increased by E2 treatment of UESCs in the presence of P4. Treatment with E2 also promoted prostaglandin E2 (PGE2) synthesis by UESCs. Depletion of Bmal1 in UESCs by small-interfering RNA (siRNA) decreased the transcript levels of clock genes (Nr1d1 and Dbp), Vegf, and Ptgs2 compared with nonsilencing siRNA treatment. Bmal1 knockdown also inhibited PGE2 synthesis. Moreover, the mRNA expression levels of clock genes (Nr1d1 and Dbp), Vegf, and Ptgs2, and their respective proteins were significantly decreased in the uterus of Bmal1-/- mice. Thus, these data suggest that Bmal1 in mice promotes PGE2 synthesis by upregulating Ptgs2 in response to increases in E2 on D4 of pregnancy.NEW & NOTEWORTHY Rhythmic expression of Bmal1 and Ptgs2 was observed in the uterus isolated from D3.5-4.5 of pregnant mice. E2 increased the expression of Bmal1 and Ptg2 in UESCs isolated from mice on D4. The expression of Ptgs2 was significantly decreased in Bmal1-siRNA treated UESCs. Bmal1 knockdown also inhibited PGE2 synthesis. Thus, these data suggest that Bmal1 in mice promotes PGE2 synthesis by upregulating Ptgs2 in response to increases in E2 on D4 of pregnancy.