Prostaglandin Research Articles

Role of Mast Cell in Hyperalgesic Priming and the Preventive Effect of Electroacupuncture on the Transition from Acute to Chronic Pain

Objective: Injury can lead to long-term changes that increase the sensitivity of afferent nerve endings to subsequent stimulation and pain can transition from acute to chronic. This phenomenon is known as hyperalgesic priming (HP). This study aimed to understand the mechanisms underlying the effect of Electroacupuncture (EA) on HP and optimize acupoint selection for EA to prevent pain transition. Methods: A rat HP model was established using sequential intraplantar injections of carrageenan (Cg) and prostaglandin E2 (PGE2). The pain thresholds were measured using von Frey filaments. EA on bilateral Zusanli(ST36) and Kunlun(BL60) was used to prevent pain transition. The number of mast cells in the ipsilateral hindpaw skin was determined using toluidine blue or fluorescence-labeled avidin staining. The protein expression levels of protein kinase C (PKCε) in the lumbar dorsal root ganglions (DRGs) were detected by western blotting 24 h after PGE2 injection. Serial pharmacological experiments were conducted to evaluate the relationship between mast cells and pain transition. Finally, EA on the bilateral ST36 and Chongyang(ST42) or a novel combination (ST36 and ST42 on the ipsilateral side, and ST36 and BL60 on the contralateral side) was used to prevent pain transition. Results: Although EA applied to ST36 and BL60 alleviated acute pain induced by Cg injection, it failed to prevent the pain transition caused by PGE2 injection. Mast cell accumulation in the ipsilateral hind paw was observed 7 days after Cg injection. Furthermore, mast cell degranulation may be responsible for PKCε activation in the DRG, a marker of pain transition. EA significantly decreased the number of mast cells in the skin of the ipsilateral hind paw when applied at ST36 and ST42, but not when applied at ST36 and BL60. Furthermore, EA employed to ST36 and ST42 significantly reversed long-term hyperalgesia induced by PGE2 injection, even when administered before injection. However, EA did not alleviate acute pain caused by Cg injection. By using a novel acupoint combination, EA simultaneously alleviated acute pain and prevented pain transition. Conclusions: Our study suggests that mast cells play a critical role in both HP and the transition from acute to chronic pain, whereas EA can prevent pain transition by decreasing the number of mast cells in the local tissue. Graphical abstract: http://links.lww.com/AHM/A144.

Abstract Su206: Early Metabolic Effects of Prehospitally Administered High-Dose Glucocorticoids in Comatose Patients Resuscitated from Out-of-Hospital Cardiac Arrest

Background: Administration of glucocorticoid in comatose patients resuscitated from out-of-hospital cardiac arrest (OHCA) mitigate the inflammatory response within the first 24 hours. The anti-inflammatory action is mediated through genomic effects, taking hours to days to set in, but glucocorticoids may also exert acute, non-genomic effects. The interplay between inflammation and metabolism is becoming more evident and emerging evidence suggests that early metabolic interventions can reduce reactive oxygen species, thus preventing cell apoptosis and necrosis. Hence, it is pivotal to investigate whether glucocorticoids cause significant metabolic effects in this context. Methods: Sub-study of a two-center, blinded, randomized controlled trial (NCT04624776) examining the effects of prehospital administration of 250 mg methylprednisolone versus placebo in comatose patients resuscitated from OHCA of presumed cardiac cause. Blood samples were collected upon hospital arrival (T0) and 48 hours later (T48). A total of 60 metabolites were quantified by mass-spectrometry and compared between groups following adjustment for sex, age, time to return of spontaneous circulation (ROSC), ST-elevation myocardial infarction, and time from intervention to sampling (only at T0). All results were corrected using the false-discovery rate method to account for multiple tests. Results: In the modified intention to treat population (mITT) 68 (50%) had been randomized to glucocorticoid and 69 (50%) to placebo. Blood samples were available for 121 (88%) and 117 (82%) patients at T0 and T48, respectively. Median age was 66 years (IQR: 56- 74) and 100 (83%) patients were men. Median time to ROSC was 16 min (10-20), and study medicine was administered prehospital 20 min (13-29) following ROSC with blood samples at T0 being drawn after 107 min (64-180). Though a nominal difference was observed at hospital arrival (Figure 1 left), we found no metabolic effects following correction for multiple testing. At T48, glucocorticoid showed increased plasma levels of many amino acids, especially tryptophan (Figure 1 right), while prostaglandin E2 and free fatty acids associated with inflammation were higher in the placebo group. Discussion: We did not find evidence for early metabolic effects of glucocorticoid treatment after OHCA. In contrast, several metabolites were affected at T48, including an increase in plasma tryptophan levels in the glucocorticoid group and lower levels of prostaglandin E2.

Abstract 4118993: β1 Adrenergic Receptor Autoantibodies Promote Heart Failure Though Activation of Prostaglandin E2 Receptor EP1/Phosphodiesterase 4B Pathway

Background: β1 adrenergic receptor (β1-AR) autoantibodies (β1-AA) can cause heart failure (HF) through activating of β1-AR; However, β-AR antagonists cannot completely reverse the cardiac injury induced by β1-AA and improve the survival rate of patients with β1-AA-positive HF. However, the β1-AR-independent mechanisms of heart failure induced by β1-AA are unclear. Methods: Proteomics of mice hearts was used to identify the specific changed proteins induced by β1-AA. The expression of phosphodiesterase 4B (PDE4B) was detected by western blot in neonatal mice mouse cardiomyocytes (NMCMs) and heart tissues. The binding proteins with β1-AA were enriched by immunoprecipitation (IP) and identified by mass spectrum. The interaction between β1-AA and prostaglandin E2 Receptor EP1 was detected by co-IP and surface plasmon resonance. The cardiac function and cardiac remodeling of PDE4B transgenic (TG) mice and EP1 knockout (KO) mice. Results: Firstly, PDE4B was changed the most proteins induced by β1-AA compared to β1 adrenergic receptor dobutamine. Moreover, the decrease of PDE4B induced by β1-AA cannot be reversed by metoprolol in vivo and in vitro. Secondly, the cAMP/PKA pathway and cardiac injury/dysfunction induced by β1-AA were inhibited after activation of PDE4B or PDE4B-TG in vivo and in vitro. Thirdly, β1-AA can bind with EP1 and activate Gq/IP3 pathway. The activation effect was abolished by EP1 antagonist. Lastly, blocked EP1 or EP1-KO will reverse the decreased PDE4B and cardiac injury/dysfunction induced by β1-AA. Conclusions: Our work reveals that β1-AA can activate of EP1/PDE4B pathway to result in heart failure.

CNSC-37. ROLE OF PGE2-REGULATED NEUROINFLAMMATION IN CONSTRUCTING NEURON-NK-GLIOMA CIRCUIT FOR GLIOBLASTOMA

Abstract Glioblastoma (GBM), known for its aggressive nature and poor prognosis, frequently recurs and resists standard treatments such as temozolomide (TMZ). This resistance is partly due to complex interactions within the tumor microenvironment, particularly involving neuronal excitation. Recent insights suggest that neuronal activity, through mechanisms like neurogliomal synapses, not only promotes glioma cell proliferation but also contributes to the chemoresistance observed in recurrent tumors. Our focus is on Prostaglandin E2 (PGE2), a mediator that regulates neuronal excitation, and its role in the recurrence and resistance of GBM. We discovered that PGE2 upregulates synaptic proteins and alters neurotransmitter profiles, enhancing tumor cell survival and resistance to TMZ. Specifically, increased levels of neurotransmitters such as glutamine and asparagine were observed in PGE2-rich environments, correlating with heightened chemoresistance and tumor recurrence. Co-culture experiments further demonstrated that PGE2-treated neuronal cells could induce resistance in adjacent GBM cells. These findings highlight the potential of targeting PGE2 pathways as a therapeutic strategy. A significant advancement in our study was the development and application of compound #038, a novel celecoxib derivative designed to cross the blood-brain barrier (BBB). This compound demonstrated enhanced efficacy in inhibiting GBM growth and improving survival rates in mouse models, indicating its potential as an effective therapeutic agent against GBM.

The Altered Lipid Composition and Key Lipid Metabolic Enzymes in Thiacloprid-Resistant Myzus persicae, with Special Attention Paid to the Function of MpTHEM6a

Neonicotinoid resistance is increasingly prevalent in the agricultural pest Myzus persicae. Lipids play a critical role in insect defense systems, but their contribution to insect neonicotinoid resistance is disregarded. We conducted metabolomics and transcriptomics studies on M. persicae thiacloprid-resistant (THG-R) and -susceptible (FFJ-S) populations. A total of 149 lipid metabolites were identified, with 90 upregulated and 59 downregulated in THG-R compared to in FFJ-S. Metabolites in the arachidonic acid (AA) pathway substantially varied between THG-R and FFJ-S. For example, arachidonic acid, (±)11-HETE, and prostaglandin B1 were significantly upregulated, while prostaglandin A1, tetranor-PGDM, 8,15-diHETE, and (±)11(12)-EET were significantly decreased in THG-R. Transcriptomics profiles and qPCR indicated that lipid metabolic enzymes, including fatty acid synthase (FAS), the elongase of very-long-chain fatty acids (ELO), fatty acid desaturase (FAD), and phospholipase (PL) genes, were not overexpressed in THG-R. Among the twelve thioesterase genes, only MpTHEM6a was significantly upregulated in THG-R. Knocking down the expression of MpTHEM6a in THG-R significantly increased the toxicity of the three neonicotinoids, reduced the lifespan of adults, and decreased the number of nonviable nymphs produced by female adults. The metabolites AA, (±)11-HETE, and prostaglandin B1 are potential biomarkers in neonicotinoid-resistant M. persicae. MpTHEM6a may become a potential target for combating neonicotinoid-resistant M. persicae.

Thermoregulation and survival during sepsis: insights from the cecal ligation and puncture experimental model

BackgroundSepsis remains a major global health concern due to its high prevalence and mortality. Changes in body temperature (Tb), such as hypothermia or fever, are diagnostic indicators and play a crucial role in the pathophysiology of sepsis. This study aims to characterize the thermoregulatory mechanisms during sepsis using the cecal ligation and puncture (CLP) model and explore how sepsis severity and ambient temperature (Ta) influence Tb regulation and mortality. Rats were subjected to mild or severe sepsis by CLP while housed at thermoneutral (28 °C) or subthermoneutral (22 °C) Ta, and their Tb was monitored for 12 h. Blood and hypothalamus were collected for cytokines and prostaglandin E2 (PGE2) analysis.ResultsAt 28 °C, febrile response magnitude correlated with sepsis severity and inflammatory response, with tail vasoconstriction as the primary heat retention mechanism. At 22 °C, Tb was maintained during mild sepsis but dropped during severe sepsis, linked to reduced UCP1 expression in brown adipose tissue and less effective vasoconstriction. Despite differences in thermoregulatory responses, both Ta conditions induced a persistent inflammatory response and increased hypothalamic PGE2 production. Notably, mortality in severe sepsis was significantly higher at 28 °C (80%) compared to 22 °C (0%).ConclusionsOur findings reveal that ambient temperature and the inflammatory burden critically influence thermoregulation and survival during early sepsis. These results emphasize the importance of considering environmental factors in preclinical sepsis studies. Although rodents in experimental settings are often adapted to cold environments, these conditions may not fully translate to human sepsis, where cold adaptation is rare. Thus, researchers should carefully consider these variables when designing experiments and interpreting translational implications.Graphical Graphical representation of the thermoregulatory and inflammatory responses to mild and severe sepsis in rats housed at thermoneutral (28 °C) and subthermoneutral (22 °C) ambient temperatures (Ta). The model highlights distinct body temperature outcomes: fever and hypothermia. At thermoneutral Ta, severe sepsis induces a high fever, associated with increased hypothalamic PGE2, cytokine levels, and mortality, while mild sepsis leads to a moderate fever. In contrast, at subthermoneutral Ta, severe sepsis results in hypothermia with decreased UCP1 expression and lower mortality, whereas mild sepsis maintains normal body temperature. The impact of Ta on sepsis severity, thermoregulatory mechanisms, and survival is emphasized.

A Study Into Systemic and Oral Levels of Proinflammatory Biomarkers Associated With Endpoints After Active Non‐Surgical Periodontal Therapy

ABSTRACTAimTo analyse whether some selected inflammatory biomarkers collected from venous blood and gingival crevicular fluid (GCF) were associated with the outcome of non‐surgical periodontal therapy.Materials and MethodsTwo‐hundred and nine patients affected by periodontitis were enrolled in the study, who had undergone steps I and II therapy as well as a non‐surgical re‐instrumentation (NSRI) of periodontal pockets after 6 months. Serum (SE), plasma (PL) and GCF samples were quantitatively analysed for the following inflammatory biomarkers: active matrix metalloproteinase‐8 (aMMP‐8), prostaglandin E2 (PGE2) and surfactant protein D (SP‐D). Therapy outcomes were evaluated using a ‘treat‐to‐target’ endpoint (T2T) at the patient level, defined as ≤ 4 sites with pocket depth ≥ 5 mm.ResultsPatients presented with 23 ± 6 teeth (mean ± SD) at baseline. After steps I and II therapy, 41.6% of the patients reached T2T and after NSRI 47.4%. Univariate analysis identified a potential association between high levels of PL‐SP‐D and more favourable treatment outcomes. Multivariate binary logistic regression adjusted for sex, mean baseline probing depth, diabetes and current smoking status confirmed an independent relationship between baseline PL‐SP‐D and the T2T after steps I and II therapy (aOR 0.432, p = 0.011), implying that a higher level PL‐SP‐D at baseline is associated with a > 50% reduced risk of failing T2T. However, no such association was found for PL‐SP‐D and NSRI.ConclusionHigher baseline PL‐SP‐D levels might be associated with more favourable treatment outcomes after steps I and II therapy. This may be due to its role in the regulation of neutrophil function. However, further investigation is required to confirm this hypothesis. If proven, PL‐SP‐D could play a role as a biomarker for identifying individuals who respond differentially to primary therapy.

Lipopolysaccharide-mediated effects of the microbiota on sleep and body temperature

Recent research suggests that microbial molecules translocated from the intestinal lumen into the host’s internal environment may play a role in various physiological functions, including sleep. Previously, we identified that butyrate, a short-chain fatty acid produced by intestinal bacteria, and lipoteichoic acid, a cell wall component of gram-positive bacteria, induce sleep when their naturally occurring translocation is mimicked by direct delivery into the portal vein. Building upon these findings, we aimed to explore the sleep signaling potential of intraportally administered lipopolysaccharide (LPS), a primary component of gram-negative bacterial cell walls, in rats. Low dose of LPS (1 μg/kg) increased sleep duration and prolonged fever, without affecting systemic LPS levels. Interestingly, administering LPS systemically outside the portal region at a dose 20 times higher did not affect sleep, indicating a localized sensitivity within the hepatoportal region for the sleep and febrile effects of LPS. Furthermore, both the sleep- and fever-inducing effects of LPS were inhibited by indomethacin, a prostaglandin synthesis inhibitor, and replicated by intraportal administration of prostaglandin E2 or arachidonic acid, suggesting the involvement of the prostaglandin system in mediating these actions.

Pivotal roles for cancer cell-intrinsic mPGES-1 and autocrine EP4 signaling in suppressing antitumor immunity.

Tumor cell-derived prostaglandin E2 (PGE2) is a tumor cell-intrinsic factor that supports immunosuppression in the tumor microenvironment (TME) by acting on the immune cells, but the impact of PGE2 signaling in tumor cells on the immunosuppressive TME is unclear. We demonstrate that deleting the PGE2 synthesis enzyme or disrupting autocrine PGE2 signaling through EP4 receptors on tumor cells reverses the T cell-low, myeloid cell-rich TME, activates T cells, and suppresses tumor growth. Knockout (KO) of Ptges (the gene encoding the PGE2 synthesis enzyme mPGES-1) or the EP4 receptor gene (Ptger4) in KPCY (KrasG12D P53R172H Yfp CrePdx) pancreatic tumor cells abolished growth of implanted tumors in a T cell-dependent manner. Blockade of the EP4 receptor in combination with immunotherapy, but not immunotherapy alone, induced complete tumor regressions and immunological memory. Mechanistically, Ptges- and Ptger4-KO tumor cells exhibited altered T and myeloid cell attractant chemokines, became more susceptible to TNF-α-induced killing, and exhibited reduced adenosine synthesis. In hosts treated with an adenosine deaminase inhibitor, Ptger4-KO tumor cells accumulated adenosine and gave rise to tumors. These studies reveal an unexpected finding - a nonredundant role for the autocrine mPGES-1/PGE2/EP4 signaling axis in pancreatic cancer cells, further nominating mPGES-1 inhibition and EP4 blockade as immune-sensitizing therapy in cancer.

Clinical effects of anweiyang capsule and Pinellia decoction for eradication of Helicobacter pylori and healing of peptic ulcers

Peptic ulcers are a prevalent and often chronic condition within the digestive system, frequently prone to recurrence. This study aims to evaluate the clinical effects of Anweiyang capsule combined with Pinellia Heart-Draining Decoction on Helicobacter pylori eradication, ulcer healing rates, and improvement of Traditional Chinese Medicine (TCM) syndromes in patients with peptic ulcers. A total of 100 patients were randomly assigned to an observation group (n = 50), receiving the herbal combination, and a control group (n = 50), receiving standard Western medical treatment. The total effective rate was significantly (P < 0.05) higher in the observation group (96%) compared to the control group (80%). After 4 weeks of treatment, serum procalcitonin (PCT) and C-reactive protein (CRP) levels decreased, while prostaglandin E2 (PGE2) levels increased in both groups; however, the observation group exhibited better results (P < 0.05). The observation group achieved a H. pylori eradication rate of 94% and an ulcer healing rate of 82%, compared to 64% and 56% in the control group, respectively. Improvement in TCM syndrome scores was more significant in the observation group (P < 0.05). Moreover, the incidence of adverse reactions was significantly (P < 0.05) lower in the observation group (4%) compared to the control group (18%). In conclusion, Anweiyang capsule combined with Pinellia Heart-Draining Decoction significantly enhances the eradication rate of H. pylori and the ulcer healing rate without substantially increasing the risk of adverse reactions, demonstrating its safety and reliability for patients.

Salmon Nasal Cartilage-Derived Proteoglycans Alleviate Monosodium Iodoacetate-Induced Osteoarthritis in Rats

Osteoarthritis is a chronic inflammatory condition characterized by the degeneration of joint cartilage and underlying bone, resulting in pain, swelling, and reduced mobility. This study evaluates the efficacy of salmon nasal cartilage-derived proteoglycans in mitigating osteoarthritis symptoms and investigates the underlying molecular mechanisms. This study employed a rat model of osteoarthritis induced by monosodium iodoacetate (MIA) injection. The rats were orally administered salmon nasal cartilage-derived proteoglycans or ibuprofen. Key aspects of osteoarthritis pathology, including impaired exercise ability, inflammation, extracellular matrix degradation, and chondrocyte apoptosis, were assessed using histological analysis, micro-CT, treadmill testing, serum assays, and mRNA/protein expression studies. The MIA injection caused significant cartilage damage, reduced bone mineral density, and impaired exercise ability. Additionally, it elevated serum levels of prostaglandin E2 and nitric oxide, increased the mRNA and protein levels of inflammation-related factors, and activated apoptosis signaling pathways in cartilage. Treatment with salmon nasal cartilage-derived proteoglycans significantly improved cartilage morphology and mineralization, reduced inflammation, and inhibited apoptosis signaling pathways, with effects comparable to those observed with ibuprofen treatment. These findings highlight the potential of salmon nasal cartilage-derived proteoglycans as a therapeutic agent for managing osteoarthritis by effectively reducing inflammation, preventing cartilage degradation, and inhibiting chondrocyte apoptosis.

Homocysteine aggravates intestinal inflammation through promotion of 5-LOX and COX-2 in IBD

BackgroundHomocysteine (Hcy) is a pro-inflammatory molecule that has the potential to induce oxidative damage to cells and stimulate the release of inflammatory mediators. Hcy has been observed to enhance the production of inflammatory agents in vascular endothelial cells. However, the impact of Hcy on intestinal mucosal inflammation remains largely unexplored. Therefore, the objective of this study was to examine the potential of Hcy to stimulate the synthesis of inflammatory mediators and elucidate the underlying mechanisms in the intestinal mucosa.MethodsA total of 99 patients diagnosed with inflammatory bowel disease (IBD) and 10 healthy individuals were included in this study to assess the impact of homocysteine (Hcy) on the levels of leukotriene E4 (LTE4) and prostaglandin E2 (PGE2). The underlying mechanism responsible for the generation of LTE4 and PGE2 induced by Hcy was investigated using colitis rats and Caco-2 cells. 32 Sprague–Dawley rats were categorized into four groups: normal control, TNBS model, normal with Hcy injection, and TNBS model with Hcy injection. The mRNA expressions of 5-LOX, COX-2, and NF-κB were assessed using reverse transcription quantitative polymerase chain reaction (RT-qPCR). Caco-2 cells were subjected to treatment with varying concentrations (10, 20, 50, 100 μmol/L) of Hcy and incubated for different durations (1, 3, 6 h). The alterations in NF-κB activity, as well as the levels of Hcy, LTE4, and PGE2, were measured using enzyme-linked immunosorbent assay (ELISA).ResultsThe excretion of Hcy, LTE4, and PGE2 in urine exhibited significant increases in patients with inflammatory bowel disease (IBD), Crohn's disease (CD), and ulcerative colitis (UC). In addition, Hcy demonstrated a significant increase in the expression of 5-LOX, COX-2, and NF-κB, as well as elevated levels of LTE4 and PGE2 in rats with colitis. Furthermore, Hcy was found to induce NF-κB activation and nuclear translocation, thereby contributing to the enhanced synthesis of LTE4 and PGE2 in Caco-2 cells.ConclusionsHcy was found to enhance the expression of 5-LOX and COX-2 by activating NF-κB, thereby augmenting the production of LTE4 and PGE2, which ultimately exacerbates colonic inflammation in individuals with inflammatory bowel disease (IBD).

Exploring COX-Independent Pathways: A Novel Approach for Meloxicam and Other NSAIDs in Cancer and Cardiovascular Disease Treatment

As a fundamental process of innate immunity, inflammation is associated with the pathologic process of various diseases and constitutes a prevalent risk factor for both cancer and cardiovascular disease (CVD). Studies have indicated that several non-steroidal anti-inflammatory drugs (NSAIDs), including Meloxicam, may prevent tumorigenesis, reduce the risk of carcinogenesis, improve the efficacy of anticancer therapies, and reduce the risk of CVD, in addition to controlling the body’s inflammatory imbalances. Traditionally, most NSAIDs work by inhibiting cyclooxygenase (COX) activity, thereby blocking the synthesis of prostaglandins (PGs), which play a role in inflammation, cancer, and various cardiovascular conditions. However, long-term COX inhibition and reduced PGs synthesis can result in serious side effects. Recent studies have increasingly shown that some selective COX-2 inhibitors and NSAIDs, such as Meloxicam, may exert effects beyond COX inhibition. This emerging understanding prompts a re-evaluation of the mechanisms by which NSAIDs operate, suggesting that their benefits in cancer and CVD treatment may not solely depend on COX targeting. In this review, we will explore the potential COX-independent mechanisms of Meloxicam and other NSAIDs in addressing oncology and cardiovascular health.

Phase 2b program with sonlicromanol in patients with mitochondrial disease due to m.3243A>G mutation.

Mitochondrial disease is a group of rare conditions, with no approved treatment to date, except for Leber hereditary optic neuropathy. Therapeutic options to alleviate the symptoms of mitochondrial disease are urgently needed. Sonlicromanol is a promising candidate, as it positively alters the key metabolic and inflammatory pathways associated with mitochondrial disease. Sonlicromanol is a reductive and oxidative distress modulator, selectively inhibiting microsomal prostaglandin E1 synthase activity. This Phase 2b program, aiming at evaluating sonlicromanol in adults with m.3243A>G mutation and primary mitochondrial disease, consisted of a randomized controlled (RCT) study (dose-selection) followed by a 52-week open-label extension study (EXT, long-term tolerability, safety, and efficacy of sonlicromanol). Patients were randomized (1:1:1) to receive 100- or 50-mg sonlicromanol, or placebo twice daily (bid) for 28 days with ≥2-week wash-out period between treatments. Patients who completed the RCT study entered the EXT study wherein they received 100-mg sonlicromanol bid. Overall, 27 patients were randomized (24 RCT patients completed all periods). 15 patients entered the EXT, and 12 patients were included in the EXT analysis set. All patients reported good tolerability and favourable safety, with pharmacokinetic results comparable to the earlier Phase 2a study. The RCT primary endpoint (change from placebo in the attentional domain of cognition score [IDN: visual identification, Cogstate]) did not reach statistical significance. Using a categorisation of the subject's period baseline a treatment effect over placebo was observed if their baseline was more affected (p=0.0338). Using this approach, there were signals of improvements over placebo in at least one dose in the Beck Depression Inventory (BDI, p=0.0143), Cognitive Failure Questionnaire (CFQ, p=0.0113), and the Depression subscale of the Hospital Anxiety and Depression Scale (p=0.0256). Statistically and/or clinically meaningful improvements were observed in the patient- and clinician-reported outcome measures at the end of the EXT study (Test of attentional performance [TAP] with alarm, p=0.0102; TAP without alarm, p=0.0047; BDI somatic, p=0.0261; BDI Total, p=0.0563; SF12 physical component score, p=0.0008). Seven of nine domains of RAND-Short form-36 like SF-36 pain improved (p=0.0105). Other promising results were observed in Neuro QoL-Fatigue-SF (p=0.0036), MiniBESTest (p=0.0009), McGill Pain Questionnaire (p=0.0105), EQ-5D-5L-VAS (p=0.0213) and EQ-5D-5L-index (p=0.0173). Most patients showed improvement in the 5× sit-to-stand test. Sonlicromanol was well-tolerated and demonstrated a favourable benefit/risk ratio for up to one year. Sonlicromanol was efficacious in patients when affected at baseline, as seen across a variety of clinically relevant domains. Long-term treatment showed more pronounced changes from baseline.

Mechanism of Asperosaponin VI Related to EGFR/MMP9/AKT/PI3K Pathway in Treatment of Rheumtoid Arthritis.

To explore the mechanism of action of asperosaponin VI (AVI) in the treatment of rheumatoid arthritis (RA) and validate it in ex vivo experiments using network pharmacology and molecular docking methods. The predicted targets of AVI were obtained from PharmMaper, UniProt and SwissTarget Prediction platforms, the disease targets were collected from Online Mendelian Inheritance in Man, Therapeutic Target Database and GeneCards databases, the intersection targets of AVI and RA were obtained from Venny 2.1.0, and the protein-protein interaction (PPI) network was obtained from STRING database, which was analyzed by Cytoscape software and screened to obtain the core targets. Cytoscape software was used to analyze PPI network and screen the core targets. Based on the Database for Annotation, Visualization and Integrated Discovery database, Gene Ontology functional and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were performed, and Cytoscape software was used to construct the "Disease-Pathway-Target-Drug" network, which was finally verified by molecular docking and animal experiments. Network pharmacological studies showed that AVI was able to modulate 289 targets, with 102 targets for the potential treatment of RA, with the core pathway being the AKT/PI3K signaling pathway, and the core targets being the epidermal growth factor receptor (EGFR) and matrix metalloproteinase 9 (MMP9). Molecular docking results showed that AVI could produce strong binding with both of the 2 core targets. In vitro cellular experiments showed that AVI reduced nitric oxide, prostaglandin E2, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and IL-1 β levels (P<0.05) and inhibited cyclooxygenase-2, nitric oxide synthase, EGFR, MMP9, phosphorylated phosphoinositide 3-kinase (p-PI3K), and phosphorylated serine-threonine kinase (p-AKT) proteins (P<0.05). The results of in vivo studies showed that AVI improved RA score and foot swelling thickness and decreased TNF-α, IL-6, p-PI3K and p-AKT levels in RA rats (P<0.05). AVI exerts anti-inflammatory and anti-RA effects which might be related to the EGFR/MMP9/AKT/PI3K pathway.

The role of mitochondrial transfer in the suppression of CD8+ T cell responses by Mesenchymal stem cells

Background. CD8+ Cytotoxic T lymphocytes play a key role in the pathogenesis of autoimmune diseases and clinical conditions such as graft versus host disease and graft rejection. Mesenchymal Stromal Cells (MSCs) are multipotent cells with tissue repair and immunomodulatory capabilities. Since they are able to suppress multiple pathogenic immune responses, MSCs have been proposed as a cellular therapy for the treatment of immune-mediated diseases. However, the mechanisms underlying their immunosuppressive properties are not yet fully understood. MSCs have the remarkable ability to sense tissue injury and inflammation and respond by donating their own mitochondria to neighboring cells. Whether mitochondrial transfer has any role in the repression of CD8+ responses is unknown.Methods and results. We have utilized CD8+ T cells from Clone 4 TCR transgenic mice that differentiate into effector cells upon activation in vitro and in vivo to address this question. Allogeneic bone marrow derived MSCs, co-cultured with activated Clone 4 CD8+ T cells, decreased their expansion, the production of the effector cytokine IFNγ and their diabetogenic potential in vivo. Notably, we found that during this interaction leading to suppression, MSCs transferred mitochondria to CD8+ T cells as evidenced by FACS and confocal microscopy. Transfer of MSC mitochondria to Clone 4 CD8+ T cells also resulted in decreased expansion and production of IFNγ upon activation. These effects overlapped and were additive with those of prostaglandin E2 secreted by MSCs. Furthermore, preventing mitochondrial transfer in co-cultures diminished the ability of MSCs to inhibit IFNγ production. Finally, we demonstrated that both MSCs and MSC mitochondria downregulated T-bet and Eomes expression, key transcription factors for CTL differentiation, on activated CD8+ T cells.Conclusion. In this report we showed that MSCs are able to interact with CD8+ T cells and transfer them their mitochondria. Mitochondrial transfer contributed to the global suppressive effect of MSCs on CD8+ T cell activation by downregulating T-bet and Eomes expression resulting in impaired IFNγ production of activated CD8+ T cells.

PGE2 Binding Affinity of Hemocyte Membrane Preparations of Manduca sexta and Identification of the Receptor-Associated G Proteins in Two Lepidopteran Species.

Prostaglandin E2 (PGE2) is an eicosanoid that mediates a range of physiological actions in vertebrates and invertebrates, including reproduction and immunity. The PGE2 receptor was identified and functionally assessed in two lepidopteran insects, Manduca sexta and Spodoptera exigua. However, its binding affinity to the receptor has not been reported. The PGE2 receptor is a G-protein coupled receptor (GPCR) although its corresponding G-protein is not identified. PGE2 binding assays were performed with membrane preparations from hemocytes of M. sexta larvae. We recorded an optimal binding in 4 h reactions conducted at pH 7.5 with 12 nM tritium-labeled PGE2. We found that hemocytes express a single population of PGE2 binding sites with a high affinity (Kd = 35 pmol/mg protein), which are specific and saturable. The outcomes of experiments on the influence of purine nucleotides suggested these are functional GPCRs. A bioinformatics analysis led to a proposed trimeric G-protein in the S. exigua transcriptome, in which the Gα subunit is classified into five different types: Gα(o), Gα(q), Gα(s), Gα(12), and Gα(f). After confirming expressions of these five types in S. exigua, individual RNA interference (RNAi) treatments were applied to the larvae using gene-specific double-stranded RNAs. RNAi treatments specific to Gα(s) or Gα(12) gene expression significantly suppressed the cellular immune responses although the RNAi treatments specific to other three Gα components did not. While PGE2 treatments led to elevated hemocyte cAMP or Ca2+ levels, the RNAi treatments specific to Gα(s) or Gα(12) genes led to significantly reduced second messenger levels under PGE2, although the RNAi treatments specific to the other three Gα components did not. These results showed that the PGE2 receptor has high PGE2 affinity in the nanomolar range and binds G-proteins containing a Gα(s) or Gα(12) trimeric component in S. exigua and M. sexta, and likely, all lepidopteran insects.

TissueGene-C induces anti-inflammatory activity and M2 macrophage polarization via activation of prostaglandin E2 signaling

Osteoarthritis (OA) is the most common form of degenerative joint disease that commonly affects the knees, hips, and hands. OA is a mechano-inflammatory disease characterized by low-grade inflammation, which results in the breakdown of the cartilage extracellular matrix (ECM) within joints, leading to pain, stiffness, and inflammation. TissueGene-C (TG-C) is a cell and gene therapy investigational drug for treating knee OA that comprises human allogenic chondrocytes and an irradiated modified cell line stably expressing transforming growth factor-β1 (TGF-β1). Previous preclinical animal studies have shown that TG-C provides pain relief via its anti-inflammatory effects and cartilage structural improvement in rat OA model. The goal of this study was to investigate the mechanism of action of TG-C, explore its anti-inflammatory activity, and identify the TG-C-derived active factor(s) responsible for its efficacy. Our results showed that TG-C induces the polarization of M2 macrophages and the upregulation of interleukin-10 (IL-10) and interleukin-1 receptor antagonist (IL-1ra) while inhibiting tumor necrosis factor alpha (TNF-α) expression. Additionally, this study identified prostaglandin E2 (PGE2) as the main bioactive factor responsible for the anti-inflammatory activity of TG-C. Our results demonstrated that PGE2 is expressed by the TG-C chondrocyte component and modulated by TGF-β1 derived from the second component of TG-C. Finally, the present study provides insight into the mechanism of action of TG-C in the treatment of OA.

Prostaglandin E2-EP2/EP4 signaling induces immunosuppression in human cancer by impairing bioenergetics and ribosome biogenesis in immune cells

While prostaglandin E2 (PGE2) is produced in human tumor microenvironment (TME), its role therein remains poorly understood. Here, we examine this issue by comparative single-cell RNA sequencing of immune cells infiltrating human cancers and syngeneic tumors in female mice. PGE receptors EP4 and EP2 are expressed in lymphocytes and myeloid cells, and their expression is associated with the downregulation of oxidative phosphorylation (OXPHOS) and MYC targets, glycolysis and ribosomal proteins (RPs). Mechanistically, CD8+ T cells express EP4 and EP2 upon TCR activation, and PGE2 blocks IL-2-STAT5 signaling by downregulating Il2ra, which downregulates c-Myc and PGC-1 to decrease OXPHOS, glycolysis, and RPs, impairing migration, expansion, survival, and antitumor activity. Similarly, EP4 and EP2 are induced upon macrophage activation, and PGE2 downregulates c-Myc and OXPHOS in M1-like macrophages. These results suggest that PGE2-EP4/EP2 signaling impairs both adaptive and innate immunity in TME by hampering bioenergetics and ribosome biogenesis of tumor-infiltrating immune cells.

The role of the cyclooxygenase-2 pathway in tissue ischemia and revascularization following skeletal muscle injury induced by bothropic snake venom

Bothrops asper venom (Bav) contains metalloproteinases that disrupt the microvascular system, impairing muscle tissue regeneration after injury. This study investigated the impact of the cyclooxygenase-2 (COX-2) pathway on vascular injury and revascularization in muscle injuries induced by Bav. Mice were injected with Bav into the gastrocnemius muscle and treated with lumiracoxib, a selective COX-2 inhibitor, 30 min, 2 days, and 6 days post-Bav injection. Muscle tissue was analyzed at 24 h, 7 days, and 21 days post-injection. A decrease in COX-2 expression at 24 h post-Bav injection indicated significant necrosis and tissue loss. Both Bav injection and lumiracoxib treatment influenced the decrease of prostaglandin (PG)D2 and PGE2 production. Seven and 21 days post-Bav injections, COX-2 expression increased, along with PGDs levels unaffected by lumiracoxib, indicating that the other isoform COX-1 pathway could contribute to the release of PGs. Bav/lumiracoxib treated animals presented exacerbated limb ischemia, implying that COX-2-derived prostaglandins preserve vessel integrity. CD31, an angiogenesis marker, initially (24 h) decreased post-Bav injection but increased at 7 and 21 days in Bav/lumiracoxib mice, suggesting a down-modulatory role for COX-2-derived prostaglandins in early angiogenesis and tissue regeneration. Vascular endothelial growth factor (VEGF) production rose 7 days post-Bav injection, supporting its role in angiogenesis. Previous treatment with lumiracoxib promoted release of VEGF levels 21 days post-Bav injury showing that the inhibition of COX-2 pathway in the early stage of revascularization stimulates the neovascularization regulated by elevated release of VEGF. Similarly, metalloproteinases (MMPs), such as MMP-9, MMP-10, and MMP-13, crucial for vascular remodeling, were elevated 21 days after Bav/lumiracoxib treatment. In conclusion, the COX-2 pathway is essential to decrease the high grade of ischemia caused by acute injury induced by Bav. However, the decrease of activity in the COX-2 pathway in the first stages of revascularization contributes to the elevated production of key pro-angiogenic mediators that up-regulate the restoration of microvasculature and blood flow in muscle tissue injured by botropic venoms.