Essential Fatty Acids and Their Metabolites in the Pathobiology of Inflammation and Its Resolution

The polysaccharide-based nanoemulsions: Preparation, mechanism, and application in food preservation-A review

The stability and bioavailability of antioxidant, antibacterial, and other bioactive substances could be improved through nanoemulsion systems, as a result, nanoemulsion technology has become popular in food preservation. Polysaccharides are green polymers, their renewability, richness, safety, and functionality determine broad application prospects. Polysaccharide-based nanoemulsion coatings with good waterproofness, and mechanical and biological properties are found to effectively prevent or delay water loss, respiration, gas exchange, and microbial corruption of fruits, vegetables, and meat products, and they will be an important innovative technology for sustainable development in the future. The structural and functional properties of polysaccharides that could stabilize nanoemulsions have been discussed, and the preparation methods, physicochemical properties, stability, and formation mechanism of nanoemulsions have been summarized in this review. In addition, the preparation methods of polysaccharide-based nanoemulsion coatings are summarized, the application and preservation mechanisms in fruits, vegetables, and meat products have been introduced, and future perspectives have been discussed. At present, the related researches mainly focus on the bactericidal activity and the sensory quality of food products, while the in-depth research is unclear, this review provides ideas for the subsequent research on polysaccharide-based nanoemulsions for food preservation.

Omics for searching plasma biomarkers associated with unfavorable COVID-19 progression in hypertensive patients

Hypertension is one of the most common risk factors for COVID-19 clinical progression. The identification of plasma biomarkers for anticipating worse clinical outcomes and to better understand the shared mechanisms between hypertension and COVID-19 are needed. A hypothesis-generating study was designed to compare plasma proteomics and metabolomics between 22 hypertensives (HT) and 41 non-hypertensives (nHT) patients with the most unfavorable COVID-19 progression. A total of 43 molecules were significantly differed between HT (n = 22) and nHT (n = 41). Random Forest (RF) analysis identified myo-inositol, gelsolin and phosphatidylcholine (PC) 32:1 as the top molecules for distinguishing between HT and nHT. Plasma myo-inositol and gelsolin were higher (P = 0.03 and P = 0.02, respectively) and plasma PC 32:1 was lower (P = 0.03) in HT compared to nHT. Biological processes like stress response and blood coagulation, along with KEGG pathways including ascorbate and aldarate metabolism (P = 0.021) and linoleic acid metabolism (P = 0.028), were altered in hypertensive patients with the most unfavorable COVID-19 progression. There is a clear link between hypertension and severe COVID-19. Key biological pathways to consider for improving the prognosis and quality of life of hypertensive patients who become infected with SARS-CoV-2 include oxidative stress, ascorbate and aldarate metabolism, lipid metabolism, immune system and inflammation.

Analysis of non-cholesterol sterols and fatty acids in patients with graves' orbitopathy: insights into lipid metabolism in relation to the clinical phenotype of disease

PURPOSE

Graves' orbitopathy (GO) is a complex inflammatory disease of the orbit. A potential link between cholesterol metabolism and the occurrence of GO is possible, but still unexplored. This study aims to investigate patients' lipid status, fatty acid content, and cholesterol homeostasis markers, all in relation to the clinical phenotype of GO.

METHODS

This cross-sectional study enrolled 89 consecutive patients with GO of varying degrees of activity and severity. Conventional lipid parameters were measured using routine biochemical methods. Concentrations of cholesterol synthesis and cholesterol absorption markers were analyzed by a GC-FID method. The percentage composition of individual fatty acids was determined by GC-FID. Total concentration of thyrotropin-receptor antibodies was measured by a binding immunoassay (Roche Diagnostics), while their stimulating activity (TSAb) was quantified using a cell-based bioassay (Quidelortho).

RESULTS

HDL-C concentration was significantly lower in patients with an active GO compared to an inactive form of GO (p = 0.032). The ApoB/ApoA1 ratio was significantly higher in a more severe GO (p = 0.029). Also, a positive correlation between LDL-C and TSAb levels (ρ = 0.255, p = 0.019) was observed. Lathosterol concentration significantly increased in more severe GO cases (p = 0.045). Moreover, the level of cholesterol synthesis-to-absorption index (CSI/CAI) positively correlated with CAS score (ρ = 0.232, p = 0.048). Palmitic acid was significantly associated with active GO (p = 0.012). The levels of desmosterol, lathosterol, CSI/CAI, and oleic acid were significantly associated with TSAb levels.

CONCLUSIONS

Alterations in patients' lipid profile and the cholesterol homeostasis were associated with a worse clinical phenotype of GO.

Delayed viral clearance and altered inflammatory responses affect severity of SARS-CoV-2 infection in aged mice

Epidemiological investigations consistently demonstrate an overrepresentation of the elderly in COVID-19 hospitalizations and fatalities, making the advanced age as a major predictor of disease severity. Despite this, a comprehensive understanding of the cellular and molecular mechanisms explaining how old age represents a major risk factor remain elusive. To investigate this, we compared SARS-CoV-2 infection outcomes in young adults (2 months) and geriatric (15-22 months) mice. Both groups of K18-ACE2 mice were intranasally infected with 500 TCID50 of SARS-CoV-2 Delta variant with analyses performed on days 3, 5, and 7 post-infection (DPI). Analyses included pulmonary cytokines, lung RNA-seq, viral loads, lipidomic profiles, and histological assessments, with a concurrent evaluation of the percentage of mice reaching humane endpoints. The findings unveiled notable differences, with aged mice exhibiting impaired viral clearance, reduced survival, and failure to recover weight loss due to infection. RNA-seq data suggested greater lung damage and reduced respiratory function in infected aged mice. Additionally, elderly-infected mice exhibited a deficient antiviral response characterized by reduced Th1-associated mediators (IFNγ, CCL2, CCL3, CXCL9) and diminished number of macrophages, NK cells, and T cells. Furthermore, mass-spectrometry analysis of the lung lipidome indicated altered expression of several lipids with immunomodulatory and pro-resolution effects in aged mice such as Resolvin, HOTrEs, and NeuroP, but also DiHOMEs-related ARDS. These findings indicate that aging affects antiviral immunity, leading to prolonged infection, greater lung damage, and poorer clinical outcomes. This underscores the potential efficacy of immunomodulatory treatments for elderly subjects experiencing symptoms of severe COVID-19.

A Micro-Flow Liquid Chromatography-Mass Spectrometry Method for the Quantification of Oxylipins in Volume-Limited Human Plasma

Oxylipins are well-known lipid mediators in various inflammatory conditions. Their endogenous concentrations range from low picomolar to nanomolar, and there are growing demands to determine their concentrations in low-volume matrices for pathological studies, including blood, cerebrospinal fluids from animal disease models, infants, and microsampling devices. Most of the published quantification methods for comprehensive profiling of oxylipins still require more than 50 µL plasma as a starting volume to detect these low levels. The aim of our study is to develop a sensitive and reliable method for the quantification of oxylipins in volume-limited human plasma samples. We established and validated a micro-liquid chromatography (LC)-mass spectrometry (MS)/MS method that requires only 5 µL of human plasma for the determination of 66 oxylipins. The optimized micro-LC-MS/MS method utilized a flow rate of 4 µL/min with a 0.3-mm inner diameter column. With an injection volume of 3 µL, our method provides limits of detection in the range from 0.1 to 91.9 pM, and limits of quantification range from 0.3 to 306.2 pM. The sensitivity enhancement compared to conventional flow ranged from 1.4 to 180.7 times for 51 compounds depending on their physical-chemical properties. After validation, the method was applied to analyze 40 plasma samples from a healthy aging study to demonstrate robustness and sensitivity.

Modulatory role of exogenous arachidonic acid in periodontitis with type 2 diabetes mellitus mice

BACKGROUND

Type 2 diabetes mellitus (T2DM) exhibits a bidirectional relationship with periodontitis, wherein each condition influences the progression of the other. Arachidonic acid (AA) exerts an anti-diabetic effect, while showing a protective effect by regulating the inflammatory response independently of its metabolites. However, its impact on periodontitis with T2DM remains poorly understood.

METHODS

The T2DM mouse model was established by combining a high-sugar and high-fat diet with streptozotocin injection, followed by silk ligation to induce periodontitis. Alterations in diabetes-associated symptoms were evaluated. Micro-computed tomography was used to measure bone-related parameters, including the distance from the cementoenamel junction to the alveolar bone crest, bone volume/total volume and bone mineral density. Targeted metabolomics analysis was conducted to evaluate the impact of exogenous AA on serum metabolite levels of AA in mice with type 2 diabetic periodontitis. 16S rRNA gene sequencing was utilized to analyze the microbial diversity. The activity of osteoclasts, levels of inflammatory factors and gene expression related to osteoclasts were investigated using TRAP staining and real-time quantitative PCR.

RESULTS

The periodontitis mouse model with T2DM was successfully established. Following two weeks of exogenous AA treatment, a reduction in fasting blood glucose levels was observed in the diabetic periodontitis mice. Exogenous AA alleviated alveolar bone loss in type 2 diabetic periodontitis mice. However, it had no substantial effect on the contents of serum AA-targeted metabolites. Exogenous AA reduced Staphylococcus in subgingival flora of type 2 diabetic periodontitis mice, but had no significant impact on microbial community structure or diversity. Furthermore, it decreased the number of osteoclasts in the alveolar bone of periodontitis with T2DM mice and increased IL-10 mRNA expression in its gingival tissue.

CONCLUSION

Exogenous AA may alleviate alveolar bone loss in T2DM mice with periodontitis by reducing the number of osteoclasts and increasing the expression of IL-10 mRNA in periodontal tissues, rather than the change of AA-targeted metabolites in serum or the composition and diversity of microorganisms in subgingival plaque. These findings may provide a potential therapeutic approach for the prevention and treatment of periodontitis with T2DM.

Electroacupuncture promotes resolution of inflammation by modulating SPMs via vagus nerve activation in LPS-induced ALI

During the process of acute lung injury (ALI) associated with sepsis, the α7nAChR in the cholinergic anti-inflammatory pathway (CAP) plays a crucial role. However, the roles of electroacupuncture (EA) and specialized pro-resolving mediators (SPMs) in this context remain unclear. In this study, we demonstrated that EA activates CAP via α7nAChR, reducing lung permeability and inflammatory cytokine release. Our results highlighted lipoxin A4 (LXA4) as a crucial SPM in this process. EA was shown to enhance LXA4 synthesis and alleviate symptoms in patients with sepsis-related acute respiratory distress syndrome (ARDS). Studies using α7nAChR-deficient mice confirmed its essential role in LXA4 regulation. Macrophages in bronchoalveolar lavage fluid (BALF) were identified as key contributors to the protective effects of LXA4, further supported by experiments involving pulmonary macrophage depletion. In summary, we discovered a novel anti-inflammatory pathway where EA activates α7nAChR, leading to increased LXA4 production and lung protection.

Mitochondrial fatty acid oxidation regulates monocytic type I interferon signaling via histone acetylation

Although lipid-derived acetyl-coenzyme A (CoA) is a major carbon source for histone acetylation, the contribution of fatty acid β-oxidation (FAO) to this process remains poorly characterized. To investigate this, we generated mitochondrial acetyl-CoA acetyltransferase 1 (ACAT1, distal FAO enzyme) knockout macrophages. 13C-carbon tracing confirmed reduced FA-derived carbon incorporation into histone H3, and RNA sequencing identified diminished interferon-stimulated gene expression in the absence of ACAT1. Chromatin accessibility at the Stat1 locus was diminished in ACAT1-/- cells. Chromatin immunoprecipitation analysis demonstrated reduced acetyl-H3 binding to Stat1 promoter/enhancer regions, and increasing histone acetylation rescued Stat1 expression. Interferon-β release was blunted in ACAT1-/- and recovered by ACAT1 reconstitution. Furthermore, ACAT1-dependent histone acetylation required an intact acetylcarnitine shuttle. Last, obese subjects' monocytes exhibited increased ACAT1 and histone acetylation levels. Thus, our study identifies an intriguing link between FAO-mediated epigenetic control of type I interferon signaling and uncovers a potential mechanistic nexus between obesity and type I interferon signaling.

Effects of Salmonella Typhimurium infection on intestinal flora and intestinal tissue arachidonic acid metabolism in Wenchang chickens

Salmonella infections can lead to intestinal inflammation and metabolic disorders in birds. However, whether arachidonic acid (ARA) metabolism is involved in Salmonella-induced intestinal inflammation remains unclear. This experiment investigated the changes in cecal flora and ARA metabolism in Hainan Wenchang chickens infected with S. Typhimurium using 16s rDNA sequencing and targeted metabolomics. The results showed that the levels of ARA metabolites were increased in the cecum tissue of Wenchang chickens after infection with S. Typhimurium, including prostaglandin E2 (PGE2), prostaglandin F2α (PGF2α), lipoxin A4 (LXA4), ± 8(9)-EET, ± 11(12)-EET, and ± 8,9-DiHETrE. The content of key enzymes for ARA production and metabolism (Phospholipase A2 PLA2 and Cyclooxygenase-2 COX-2) in chicken cecum tissues was increased after S. Typhimurium infection. The relative mRNA levels of inflammatory factors were also increased after infection, including Interferon-γ (IFN-γ), Transforming growth factor-β1 (TGF-β1), Interleukin-4 (IL-4), and Interleukin-6 (IL-6). In HD11 cells, the use of a cyclooxygenase (COX) inhibitor reduced the increased levels of COX-2 and PGF2α induced by S. Typhimurium infection and effectively reduced the inflammatory response. In addition, the number of beneficial genera (e.g., Bifidobacterium, Lactobacillus, and Odorobacterium) in the cecum of Wenchang chickens was significantly reduced after infection with S. Typhimurium. The present study revealed the structure of cecal flora in S. Typhimurium-infected Wenchang chickens. In addition, this study demonstrated that S. Typhimurium activates the ARA cyclooxygenase metabolic pathway, which in turn mediates the development of intestinal inflammation in Wenchang chickens. The results can provide data support and theoretical support for the prevention and control of avian salmonellosis.

Etodolac Single Dose Metabolic Profile Elucidation: Pharmacokinetics and Adverse Events in Healthy Volunteers

BACKGROUND/OBJECTIVES

This study investigates the metabolic profile of a single dose of etodolac in healthy volunteers, focusing on pharmacokinetics, clinical parameters, and metabolomic variations to identify biomarkers and pathways linked to drug response, efficacy, and safety.

METHODS

Thirty-seven healthy volunteers, enrolled after rigorous health assessments, received a single dose of etodolac (Flancox® 500 mg). Pharmacokinetic profiles were determined using tandem mass spectrometry analysis, and the metabolomic profiling was conducted using baseline samples (pre-dose) and samples at maximum drug concentration (post-dose) via liquid chromatography coupled with a quadrupole time-of-flight mass spectrometer. Network analysis was employed to interpret the data.

RESULTS

Correlations were observed between metabolomic profiles and pharmacokinetic parameters as well as clinical characteristics. Notably, metabolites derived from arachidonic acid, such as prostaglandins and leukotrienes, were linked to etodolac's pharmacokinetics. Other metabolites involved in pathways like cholesterol biosynthesis, bile salts, riboflavin, and retinoic acid signaling were correlated with hematological and liver function parameters. These findings are consistent with the infrequent adverse events reported by participants, including hematological and biochemical changes in liver function.

CONCLUSIONS

A set of metabolites was identified in possible associations between specific pathways and unusual side effects, comparing the metabolic profiles before and after doses of etodolac. Our results highlight the importance of optimizing drug therapy and minimizing adverse events by taking into account individual metabolic profile information.

The Metabolome Characteristics of Aerobic Endurance Development in Adolescent Male Rowers Using Polarized and Threshold Model: An Original Research

OBJECTIVE

This study aimed to explore the molecular response mechanisms of differential blood metabolites before and after 8 weeks of threshold and polarized training models using metabolomics technology combined with changes in athletic performance.

METHODS

Twenty-four male rowers aged 14-16 were randomly divided into a THR group and a POL group (12 participants each). The THR group followed a threshold training model (72%, 24%, and 4% of training time in low-, moderate-, and high-intensity zones, respectively), while the POL group followed a polarized training model (78%, 8%, and 14% training-intensity distribution). Both groups underwent an 8-week training program. Aerobic endurance changes were assessed using a 2 km maximal rowing performance test, and untargeted metabolome analysis was conducted to examine blood metabolomic changes before and after the different training interventions. Aerobic endurance changes were assessed through a 2 km maximal rowing test. Non-targeted metabolomics analysis was employed to evaluate changes in blood metabolome profiles before and after the different training interventions.

RESULTS

After 8 weeks of training, both the THR and POL groups exhibited significant improvements in 2 km maximal rowing performance (p < 0.05), with no significant differences between the groups. The THR and POL groups had 46 shared differential metabolites before and after the intervention, primarily enriched in sphingolipid metabolism, glutathione metabolism, and glycine, serine, and threonine metabolism pathways. Nine unique differential metabolites were identified in the THR group, mainly enriched in pyruvate metabolism, glycine, serine, and threonine metabolism, glutathione metabolism, and sphingolipid metabolism. A total of 14 unique differential metabolites were identified in the POL group, predominantly enriched in sphingolipid metabolism, glycine, serine, and threonine metabolism, aminoacyl-tRNA biosynthesis, and glutathione metabolism.

CONCLUSIONS

The 8-week THR and POL training models demonstrated similar effects on enhancing aerobic performance in adolescent male rowers, indicating that both training modalities share similar blood metabolic mechanisms for improving aerobic endurance. Furthermore, both the THR group and the POL group exhibited numerous shared metabolites and some differential metabolites, suggesting that the two endurance training models share common pathways but also have distinct aspects in enhancing aerobic endurance.

Copepod Lipidomics: Fatty Acid Substituents of Structural Lipids in Labidocerca aestiva, a Dominant Species in the Food Chain of the Apalachicola Estuary of the Gulf of Mexico

Zooplanktonic copepods represent a major biological mass in the marine food chain that can be affected by climate change. Monitoring the health of this critical biomass is essential for increasing our understanding of the impact of environmental changes on marine environments. Since the lipidomes of marine organisms are known to adapt to alterations in pH, temperature, and availability of metabolic precursors, lipidomics is one technology that can be used for monitoring copepod adaptations. Among the key lipid parameters that can be monitored are the fatty acid substituents of glycerolipids and glycerophospholipids. We utilized high-resolution tandem mass spectrometry (≤2 ppm mass error) to characterize the fatty acid substituents of triacylglycerols, glycerophosphocholines, ceramides, and sphingomyelins of Labidocerca aestiva. This included monitoring for furan fatty acid substituents, a family of fatty acids unique to marine organisms. These data will contribute to establishing a lipid database of the fatty acid substituents of essential structural lipids. The key findings were that polyunsaturated fatty acids (PUFAs) were only major substituents in glycerophosphocholines with 36 to 44 carbons. Triacylglycerols, ceramides, and sphingomyelins contained minimal PUFA substituents. Furan fatty acids were limited to mono- and di-acylglycerols. In summary, we have built a baseline database of the fatty acid substituents of key structural lipids in Labidocerca aestiva. With this database, we will next evaluate potential seasonal changes in these lipid substituents and long-term effects of climate change.

Proteomic and metabolomic profiling of plasma uncovers immune responses in patients with Long COVID-19

Long COVID is an often-debilitating condition with severe, multisystem symptoms that can persist for weeks or months and increase the risk of various diseases. Currently, there is a lack of diagnostic tools for Long COVID in clinical practice. Therefore, this study utilizes plasma proteomics and metabolomics technologies to understand the molecular profile and pathophysiological mechanisms of Long COVID, providing clinical evidence for the development of potential biomarkers. This study included three age- and gender-matched cohorts: healthy controls (n = 18), COVID-19 recovered patients (n = 17), and Long COVID patients (n = 15). The proteomics results revealed significant differences in proteins between Long COVID-19 patients and COVID-19 recovered patients, with dysregulation mainly focused on pathways such as coagulation, platelets, complement cascade reactions, GPCR cell signal transduction, and substance transport, which can participate in regulating immune responses, inflammation, and tissue vascular repair. Metabolomics results showed that Long COVID patients and COVID-19 recovered patients have similar metabolic disorders, mainly involving dysregulation in lipid metabolites and fatty acid metabolism, such as glycerophospholipids, sphingolipid metabolism, and arachidonic acid metabolism processes. In summary, our study results indicate significant protein dysregulation and metabolic abnormalities in the plasma of Long COVID patients, leading to coagulation dysfunction, impaired energy metabolism, and chronic immune dysregulation, which are more pronounced than in COVID-19 recovered patients.

Polyunsaturated Fatty Acids and Human Health: A Key to Modern Nutritional Balance in Association with Polyphenolic Compounds from Food Sources

Polyunsaturated fatty acids (PUFAs) are vital dietary elements that play a significant role in human nutrition. They are highly regarded for their positive contributions to overall health and well-being. Beyond the fact that they provide a substantial supply of energy to the body (a role that saturated fats can also perform), these unsaturated fatty acids and, especially, the essential ones are involved in cell membrane structure, blood pressure regulation, and coagulation; participate in the proper functioning of the immune system and assimilation of fat-soluble vitamins; influence the synthesis of pro- and anti-inflammatory substances; and protect the cardiovascular system. Modern diets like the Western diet and the American diet are rich in saturated fats found especially in fast food products, sweets, and processed foods, a fact that has led to an increase in the prevalence of metabolic diseases worldwide (obesity, type II diabetes, gout, cardiovascular disease). Nutritionists have drawn attention to the moderate consumption of saturated fats and the need to increase the intake of unsaturated fats to the detriment of saturated ones. This paper examines the biochemical roles of polyunsaturated fats, particularly essential fatty acids, and contrasts their benefits with the detrimental effects of saturated fat overconsumption. Furthermore, it highlights the necessity for dietary shifts towards increased PUFA intake to mitigate the global burden of diet-related health issues. The co-occurrence of PUFAs and polyphenols in plant-based foods highlights the sophistication of nature's design. These bioactive compounds are not randomly distributed but are present in foods humans have consumed together historically. From traditional diets like the Mediterranean, which pairs olive oil (PUFAs and polyphenols) with vegetables and legumes, to Asian cuisines combining sesame seeds with turmeric, cultural practices have long harnessed this natural synergy.

FABP5+ macrophages contribute to lipid metabolism dysregulation in type A aortic dissection

Type A aortic dissection (TAAD) is an acute onset disease with a high mortality rate. TAAD is caused by a tear in the aortic intima and subsequent blood infiltration. The most prominent characteristics of TAAD are aortic media degeneration and inflammatory cell infiltration, which disturb the structural integrity and function of nonimmune and immune cells in the aortic wall. However, to date, there is no systematic evaluation of the interactions between nonimmune cells and immune cells and their effects on metabolism in the context of aortic dissection. Here, multiomics, including bulk RNA-seq, single-cell RNA-seq, and lipid metabolomics, was applied to elucidate the comprehensive TAAD lipid metabolism landscape. Normally, monocytes in the stress response state secrete a variety of cytokines. Injured fibroblasts lack the ability to degrade lipids, which is suspected to contribute to a high lipid environment. Macrophages differentiate into fatty acid binding protein 5-positive (FABP5+) macrophages under the stimulation of metabolic substrates. Moreover, the upregulation of Fabp5+ macrophages were retrospectively validated in TAAD model mice and TAAD patients. Finally, Fabp5+ macrophages can generate a wide range of proinflammatory cytokines, which possibly contribute to TAAD pathogenesis.

Arachidonic acid regulates pluripotency by modulating cellular energetics via fatty acid synthesis and mitochondrial fission

Arachidonic acid (AA) is an important omega-6 fatty acid that can be metabolised into an impressive spectrum of biologically active mediators participating in various cellular functions. Studies have shown that fatty acid synthesis is enhanced in embryonic stem cells (ESCs), and it is crucial for the cellular reprogramming of somatic cells into induced pluripotent stem cells (iPSCs). Fatty acid synthesis increases the cellular lipid contents and, in turn, promotes mitochondrial fission and cellular reprogramming. AA was found to induce acetyl-CoA carboxylase 1 (ACC1) expression, a major enzyme in fatty acid synthesis. In this study, we have investigated the regulation of pluripotency, fatty acid synthesis and mitochondrial activities of the human induced pluripotent stem cells (hiPSCs) and the human embryonal carcinoma (hEC) NTERA-2 cells upon treatment with varying concentrations of AA. Our results indicate that a lower concentration of AA can increase pluripotency, as evidenced by an increased expression of pluripotency markers, increased fatty acid synthesis as evidenced by lipid estimation and modulated mitochondrial fission, as evidenced by mitotracker staining for fissioned mitochondria. Moreover, higher concentrations of AA-induced the opposite effect, leading to pluripotent stem cell differentiation. Molecular docking simulations predicted the possible interactions between AA and its metabolites with fatty acid synthesis regulators ACC1 and CREB1 (Cyclic adenosine monophosphate Response Element Binding Protein 1) as a mechanism for AA regulating pluripotency.

Oxylipins as therapeutic indicators of herbal medicines in cardiovascular diseases: a review

Globally, cardiovascular diseases (CVDs) remain the leading cause of death, and their prevention and treatment continue to face major challenges. Oxylipins, as novel circulating markers of cardiovascular disease, are crucial mediators linking cardiovascular risk factors such as inflammation and platelet activation, and they play an important role in unraveling cardiovascular pathogenesis and therapeutic mechanisms. Chinese herbal medicine plays an important role in the adjuvant treatment of cardiovascular diseases, which has predominantly focused on the key pathways of classic lipids, inflammation, and oxidative stress to elucidate the therapeutic mechanisms of cardiovascular diseases. However,The regulatory effect of traditional Chinese medicine on oxylipins in cardiovascular diseases remains largely unknown. With the increasing number of recent reports on the regulation of oxylipins by Chinese herbal medicine in cardiovascular diseases, it is necessary to comprehensively elucidate the regulatory role of Chinese herbal medicine in cardiovascular diseases from the perspective of oxylipins. This approach not only benefits further research on the therapeutic targets of Chinese herbal medicine, but also brings new perspectives to the treatment of cardiovascular diseases.

Study on the Mechanism of UMI-77 in the Treatment of Sepsis-Induced Acute Lung Injury Based on Transcriptomics and Metabolomics

Introduction

Sepsis-induced acute lung injury (ALI), a critical sequela of systemic inflammation, often progresses to acute respiratory distress syndrome, conferring high mortality. Although UMI-77 has demonstrated efficacy in mitigating lung injury in sepsis, the molecular mechanisms underlying its action have not yet been fully elucidated.

Methods

This study aimed to delineate the mechanism by which UMI-77 counteracts sepsis-induced ALI using comprehensive transcriptomic and metabolomic analyses.

Results

UMI-77 significantly ameliorated histopathological changes in the lungs of mice with sepsis-induced ALI Transcriptomic analysis revealed that 124 differentially expressed genes were modulated by UMI-77 and were predominantly implicated in chemokine-mediated signaling pathways, apoptosis regulation, and inflammatory responses. Integrated metabolomic analysis identified Atp4a, Ido1, Ctla4, and Cxcl10 as key genes, and inosine 5'-monophosphate (IMP), thiamine monophosphate, thymidine 3',5'-cyclic monophosphate (dTMP) as key differential metabolites. UMI-77 may regulate key genes (Atp4a, Ido1, Ctla4, and Cxcl10) to affect key metabolites (IMP, thiamine monophosphate, and dTMP) and their target genes (Entpd2, Entpd1, Nt5e, and Hprt) involved in cytokine-cytokine receptor interaction, gastric acid secretion, pyrimidine, and purine metabolism in the treatment of sepsis-induced ALI.

Conclusion

UMI-77 exerts its therapeutic effect in sepsis-induced ALI through intricate modulation of pivotal genes and metabolites, thereby influencing critical biological pathways. This study lays the groundwork for further development and clinical translation of UMI-77 as a potential therapeutic agent for sepsis-associated lung injuries.

Novel insights into the role of metabolic disorder in osteoarthritis

Osteoarthritis (OA) is a prevalent condition that affects individuals worldwide and is one of the leading causes of disability. Nevertheless, the underlying pathological mechanisms of OA remain inadequately understood. Current treatments for OA include non-drug therapies, pharmacological interventions, and surgical procedures. These treatments are mainly focused on alleviating clinical manifestations and improving patients' quality of life, but are not effective in limiting the progression of OA. The detailed understanding of the pathogenesis of OA is extremely significant for the development of OA treatment. Metabolic syndrome has become a great challenge for medicine and public health, In recent years, several studies have demonstrated that the metabolic syndrome and its individual components play a crucial role in OA. Consequently, this review summarizes the mechanisms and research progress on how metabolic syndrome and its components affect OA. The aim is to gain a deeper understanding of the pathogenesis of OA and explore effective treatment strategies.

Fatty Acid Metabolism Disruptions: A Subtle yet Critical Factor in Adverse Pregnancy Outcomes

The establishment and maintenance of pregnancy encompass a series of complex and high-energy-consuming physiological processes, resulting in a significant energy demand. Fatty acids, one of the most essential nutrients, play a crucial role in energy supply via oxidation and perform critical biological functions such as anti-inflammatory and anti-oxidant effects, which substantially impact human health. Disordered fatty acid metabolism can cause anomalies in fetal growth and development, as well as a range of pregnancy problems, which can influence the health of both the mother and the fetus. In this review, we innovatively explore the relationship between fatty acid metabolism abnormalities and pregnancy complications, emphasizing the potential of dietary interventions with polyunsaturated fatty acids in improving pregnancy outcomes. These findings provide important evidence for clinical interventions and enhance the understanding and practical application of health management during pregnancy.

Essential Fatty Acids along the Women’s Life Cycle and Promotion of a Well-balanced Metabolism

Abstract:

Linoleic acid (ω-6 LA) and α-linolenic acid (ω-3 ALA) are essential fatty acids (EFA) for human beings. They must be consumed through diet and then extensively metabolized, a process that plays a fundamental role in health and eventually in disease prevention. Given the numerous changes depending on age and sex, EFA metabolic adaptations require further investigations along the women’s life cycle, from onset to decline of the reproductive age. Thus, this review explains women’s life cycle stages and their involvement in diet intake, digestion and absorption, the role of microbiota, metabolism, bioavailability, and EFA fate and major metabolites. This knowledge is crucial to promoting lipid homeostasis according to female physiology through well-directed health strategies. Concerning this, the promotion of breastfeeding, nutrition, and physical activity is cardinal to counteract ALA deficiency, LA/ALA imbalance, and the release of unhealthy derivatives. These perturbations arise after menopause that compromise both lipogenic and lipolytic pathways. The close interplay of diet, age, female organism, and microbiota also plays a central role in regulating lipid metabolism. Consequently, future studies are encouraged to propose efficient interventions for each stage of women's cycle. In this sense, plant-derived foods and products are promising to be included in women’s nutrition to improve EFA metabolism.

Quantitative proteomics of patient fibroblasts reveal biomarkers and diagnostic signatures of mitochondrial disease

BACKGROUNDMitochondrial diseases belong to the group of inborn errors of metabolism (IEM), with a prevalence of 1 in 2,000-5,000 individuals. They are the most common form of IEM, but, despite advances in next-generation sequencing technologies, almost half of the patients are left genetically undiagnosed.METHODSWe investigated a cohort of 61 patients with defined mitochondrial disease to improve diagnostics, identify biomarkers, and correlate metabolic pathways to specific disease groups. Clinical presentations were structured using human phenotype ontology terms, and mass spectrometry-based proteomics was performed on primary fibroblasts. Additionally, we integrated 6 patients carrying variants of uncertain significance (VUS) to test proteomics as a diagnostic expansion.RESULTSProteomic profiles from patient samples could be classified according to their biochemical and genetic characteristics, with the expression of 5 proteins (GPX4, MORF4L1, MOXD1, MSRA, and TMED9) correlating with the disease cohort, thus acting as putative biomarkers. Pathway analysis showed a deregulation of inflammatory and mitochondrial stress responses. This included the upregulation of glycosphingolipid metabolism and mitochondrial protein import, as well as the downregulation of arachidonic acid metabolism. Furthermore, we could assign pathogenicity to a VUS in MRPS23 by demonstrating the loss of associated mitochondrial ribosome subunits.CONCLUSIONWe established mass spectrometry-based proteomics on patient fibroblasts as a viable and versatile tool for diagnosing patients with mitochondrial disease.FUNDINGThe NovoNordisk Foundation, Knut and Alice Wallenberg Foundation, Wellcome Centre for Mitochondrial Research, UK Medical Research Council, and the UK NHS Highly Specialised Service for Rare Mitochondrial Disorders of Adults and Children.

Omega-3 and Sports: Focus on Inflammation

Inflammation is expected in sports, especially when practiced at a high level. The human body is pushed toward its limit, and this is perceived as a "stressogenic agent". Athletes, especially elite ones, desire it because their bodies can react with super-compensation, i.e., improve muscle mass, strength, speed, resistance, and, therefore, athletic performance. Thus, the inflammatory stimuli should be there during training but also counteracted to have the body placed in the optimal conditions for reacting with super-compensation. In this sense, omega-3 fatty acids have been shown to have anti-inflammatory biochemical activity. In this review, we will present the biochemical mechanisms of action of omega-3 fatty acids through their mediators, specialized pro-resolving mediators, which have anti-inflammatory activity. A focus will be on studies on omega-3 fatty acid supplementation in sports, and we will provide indications for possible practical applications and future studies, which are undoubtedly necessary to clarify the omega-3 fatty acids used in sports practice.

Mechanism of macrophages in gout: Recent progress and perspective

Gout represents an autoinflammatory disorder instigated by monosodium urate crystals. Its primary manifestation involves the recruitment of diverse immune cell populations, including neutrophils and macrophages. Macrophages assume a pivotal role in the initiation of acute gouty inflammation and subsequent inflammatory cascades. However, recent investigations have revealed that the impact of macrophages on gout is nuanced, extending beyond a solely detrimental influence. Macrophages, characterized by different subtypes, exhibit distinct functionalities that either contribute to the progression or regression of gout. A strategy aimed at modulating macrophage polarization, rather than merely inhibiting inflammation, holds promise for enhancing the efficacy of acute gout treatment. This review centres on elucidating potential mechanisms underlying macrophage polarization in the onset and resolution of gouty inflammation, offering novel insights into the immune equilibrium of macrophages in the context of gout.

The Effects of Mesenchymal Stem Cells-Derived Exosomes on Metabolic Reprogramming in Scar Formation and Wound Healing

Pathological scarring results from aberrant cutaneous wound healing due to the overactivation of biological behaviors of human skin fibroblasts, characterized by local inordinate inflammation, excessive extracellular matrix and collagen deposition. Yet, its underlying pathogenesis opinions vary, which could be caused by increased local mechanical tension, enhanced and continuous inflammation, gene mutation, as well as cellular metabolic disorder, etc. Metabolic reprogramming is the process by which the metabolic pattern of cells undergoes a systematic adjustment and transformation to adapt to the changes of the external environment and meet the needs of their growth and differentiation. Therefore, the abnormality of metabolic reprogramming in cells within wounds and scars attaches great importance to scar formation. Mesenchymal stem cells-derived exosomes (MSC-Exo) are the extracellular vesicles that play an important role in tissue repair, cancer treatment as well as immune and metabolic regulation. However, there is not a systematic work to detail the relevant studies. Herein, we gave a comprehensive summary of the existing research on three main metabolisms, including glycometabolism, lipid metabolism and amino acid metabolism, and MSC-Exo regulating metabolic reprogramming in wound healing and scar formation for further research reference.

Metabolomic Effects of Liraglutide Therapy on the Plasma Metabolomic Profile of Patients with Obesity

BACKGROUND

Liraglutide, a long-acting glucagon-like peptide-1 receptor agonist (GLP1RA), is a well-established anti-diabetic drug, has also been approved for the treatment of obesity at a dose of 3 mg. There are a limited number of studies in the literature that have looked at changes in metabolite levels before and after liraglutide treatment in patients with obesity. To this end, in the present study we aimed to explore the changes in the plasma metabolomic profile, using liquid chromatography-high resolution mass spectrometry (LC-HRMS) in patients with obesity.

METHODS

A single-center prospective study was undertaken to evaluate the effectiveness of 3 mg liraglutide therapy in twenty-three patients (M/F: 8/15) with obesity, mean BMI 40.81 ± 5.04 kg/m2, and mean age of 36 ± 10.9 years, in two groups: at baseline (pre-treatment) and after 12 weeks of treatment (post-treatment). An untargeted metabolomic profiling was conducted in plasma from the pre-treatment and post-treatment groups using LC-HRMS, along with bioinformatics analysis using ingenuity pathway analysis (IPA).

RESULTS

The metabolomics analysis revealed a significant (FDR p-value ≤ 0.05, FC 1.5) dysregulation of 161 endogenous metabolites (97 upregulated and 64 downregulated) with distinct separation between the two groups. Among the significantly dysregulated metabolites, the majority of them were identified as belonging to the class of oxidized lipids (oxylipins) that includes arachidonic acid and its derivatives, phosphorglycerophosphates, N-acylated amino acids, steroid hormones, and bile acids. The biomarker analysis conducted using MetaboAnalyst showed PGP (a21:0/PG/F1alpha), an oxidized lipid, as the first metabolite among the list of the top 15 biomarkers, followed by cysteine and estrone. The IPA analysis showed that the dysregulated metabolites impacted the pathway related to cell signaling, free radical scavenging, and molecular transport, and were focused around the dysregulation of NF-κB, ERK, MAPK, PKc, VEGF, insulin, and pro-inflammatory cytokine signaling pathways.

CONCLUSIONS

The findings suggest that liraglutide treatment reduces inflammation and modulates lipid metabolism and oxidative stress. Our study contributes to a better understanding of the drug's multifaceted impact on overall metabolism in patients with obesity.

Dysregulation of the Arachidonic Acid Pathway in Cystic Fibrosis: Implications for Chronic Inflammation and Disease Progression

Cystic fibrosis (CF) is the most common fatal genetic disease among Caucasian people, with over 2000 mutations in the CFTR gene. Although highly effective modulators have been developed to rescue the mutant CFTR protein, unresolved inflammation and persistent infections still threaten the lives of patients. While the central role of arachidonic acid (AA) and its metabolites in the inflammatory response is widely recognized, less is known about their impact on immunomodulation and metabolic implications in CF. To this end, here we provided a comprehensive analysis of the AA metabolism in CF. In this context, CFTR dysfunction appeared to complexly disrupt normal lipid processing, worsening the chronic airway inflammation, and compromising the immune responses to bacterial infections. As such, potential strategies targeting AA and its inflammatory mediators are being investigated as a promising approach to balance the inflammatory response while mitigating disease progression. Thus, a deeper understanding of the AA pathway dysfunction in CF may open innovative avenues for designing more effective therapeutic interventions.

How Membrane Phospholipids Containing Long-Chain Polyunsaturated Fatty Acids and Their Oxidation Products Orchestrate Lipid Raft Dynamics to Control Inflammation

BACKGROUND

Long-chain PUFA (LC-PUFA) influence varying aspects of inflammation. One mechanism by which they regulate inflammation is by controlling the size and molecular composition of lipid rafts. Lipid rafts are sphingolipid/cholesterol-enriched plasma membrane microdomains that compartmentalize signaling proteins and thereby control downstream inflammatory gene expression and cytokine production.

OBJECTIVES

This review summarizes developments in our understanding of how LC-PUFA acyl chains of phospholipids, in addition to oxidized derivatives of LC-PUFAs such as oxidized 1-palmitoyl-2-arachidonyl-phosphatidylcholine (oxPAPC), manipulate formation of lipid rafts and thereby inflammation.

METHODS

We reviewed the literature, largely from the past 2 decades, on the impact of LC-PUFA acyl chains and oxidized products of LC-PUFAs on lipid raft biophysical organization of myeloid and lymphoid cells. The majority of the studies are based on rodent or cellular experiments with supporting mechanistic studies using biomimetic membranes and molecular dynamic simulations. These studies have focused largely on the LC-PUFA docosahexaenoic acid, with some studies addressing eicosapentaenoic acid. A few studies have investigated the role of oxidized phospholipids on rafts.

RESULTS

The biophysical literature suggests a model in which n-3 LC-PUFAs, in addition to oxPAPC, localize predominately to nonraft regions and impart a disordering effect in this environment. Rafts become larger because of the ensuing increase in the difference in order between raft and nonrafts. Biochemical studies suggest that some n-3 LC-PUFAs can be found within rafts. This deviation from homeostasis is a potential trigger for controlling aspects of innate and adaptive immunity.

CONCLUSION

Overall, select LC-PUFA acyl chains and oxidized acyl chains of phospholipids control lipid raft dynamics and downstream inflammation. Gaps in knowledge remain, particularly on underlying molecular mechanisms by which plasma membrane receptor organization is controlled in response to oxidized LC-PUFA acyl chains of membrane phospholipids. Validation in humans is also an area for future study.

Explore the genetic exposure to alopecia areata

BACKGROUND

Alopecia areata is an autoimmune hair loss disorder with an incompletely understood etiology. Although trace elements, serum metabolites, and inflammatory factors are implicated in the disease, the potential causal relationships between these factors and alopecia areata require further investigation.

METHODS

This study employed Mendelian randomization (MR), utilizing data from genome-wide association studies, to explore the causal relationships between 15 trace elements, 1400 serum metabolites, and 91 inflammatory factors and alopecia areata. The analysis was conducted using the inverse variance weighted (IVW) method complemented by various sensitivity analyses, including Cochran's Q test, MR-Egger regression intercept test, MR-PRESSO global test, and leave-one-out analysis, to assess the robustness of the results.

RESULTS

MR analysis indicated a negative correlation between copper levels and the risk of developing alopecia areata (odds ratio = 0.86, 95% confidence interval: 0.75-0.99, p = 0.041). Additionally, causal relationships were identified between 15 serum metabolites and 6 inflammatory factors and the risk of alopecia areata (IVW, all p values < 0.05).

CONCLUSION

This study provides genetic evidence of the relationships between trace elements, serum metabolites, and alopecia areata, underscoring the potential value of targeted therapeutic strategies and preventive measures. Future research should expand to diverse populations and further explore the specific roles of these biomarkers in the disease mechanism.

Is there a role for essential fatty acids in osteoporosis?

Inflammatory markers are inversely associated with bone density, geometry, and strength in postmenopausal women, and elderly subjects suggesting that osteoporosis is a low-grade systemic inflammatory condition. But glucocorticoids that are potent anti-inflammatory compounds instead of arresting/preventing osteoporosis induce osteoporosis. These results indicate that IL-6 and TNF-α, post-menopausal state, and steroids produce osteoporosis by an unidentified mechanism. Pro-inflammatory cytokines, estrogen, and steroids bring about their actions by influencing the metabolism of essential fatty acids (EFAs). I propose that EFAs and their metabolites act as second messengers of actions of corticosteroids, cytokines, and estrogen. This implies that EFAs are of benefit in the prevention and management of osteoporosis. This argument is supported by the observation that plasma phospholipid content of unsaturated fatty acids is decreased in those with osteoporosis. The reports that long-chain metabolites of EFAs including arachidonic acid, docosahexaenoic acid and eicosapentaenoic acid, and lipoxin A4 are of benefit in the prevention and management of osteoporosis lends further support to this proposal.

Neuroimmune cell interactions and chronic infections in oral cancers

Inflammation is a process that is associated with the activation of distal immunosuppressive pathways that have evolved to restore homeostasis and prevent excessive tissue destruction. However, long-term immunosuppression resulting from systemic and local inflammation that may stem from dysbiosis, infections, or aging poses a higher risk for cancers. Cancer incidence and progression dramatically increase with chronic infections including HIV infection. Thus, studies on pro-tumorigenic effects of microbial stimulants from resident microbiota and infections in the context of inflammation are needed and underway. Here, we discuss chronic infections and potential neuro-immune interactions that could establish immunomodulatory programs permissive for tumor growth and progression.

Exploring the regulatory role of tsRNAs in the TNF signaling pathway: Implications for cancer and non-cancer diseases

Transfer RNA-derived small RNAs (tsRNAs), a recently identified subclass of small non-coding RNAs (sncRNAs), emerge through the cleavage of mature transfer RNA (tRNA) or tRNA precursors mediated by specific enzymes. The tumor necrosis factor (TNF) protein, a signaling molecule produced by activated macrophages, plays a pivotal role in systemic inflammation. Its multifaceted functions include the capacity to eliminate or hinder tumor cells, enhance the phagocytic capabilities of neutrophils, confer resistance against infections, induce fever, and prompt the production of acute phase proteins. Notably, four TNF-related tsRNAs have been conclusively linked to distinct diseases. Examples include 5'tiRNA-Gly in skeletal muscle injury, tsRNA-21109 in systemic lupus erythematosus (SLE), tRF-Leu-AAG-001 in endometriosis (EMs), and tsRNA-04002 in intervertebral disk degeneration (IDD). These tsRNAs exhibit the ability to suppress the expression of TNF-α. Additionally, KEGG analysis has identified seven tsRNAs potentially involved in modulating the TNF pathway, exerting their influence across a spectrum of non-cancerous diseases. Noteworthy instances include aberrant tiRNA-Ser-TGA-001 and tRF-Val-AAC-034 in intrauterine growth restriction (IUGR), irregular tRF-Ala-AGC-052 and tRF-Ala-TGC-027 in obesity, and deviant tiRNA-His-GTG-001, tRF-Ser-GCT-113, and tRF-Gln-TTG-035 in irritable bowel syndrome with diarrhea (IBS-D). This comprehensive review explores the biological functions and mechanisms of tsRNAs associated with the TNF signaling pathway in both cancer and other diseases, offering novel insights for future translational medical research.

Serum and urine metabolomics based on UPLC-QTOF/MS reveal the effect and potential mechanism of "schisandra-evodia" herb pair in the treatment of Alzheimer's disease

The "schisandra-evodia" herb pair (S-E) is a herbal preparation to treat Alzheimer's disease (AD). This study aims to investigate the therapeutic efficacy and potential mechanism of S-E in AD rats, utilizing pharmacodynamic assessments and serum- and urine-based metabolomic analyses. Pharmacodynamic assessments included Morris water maze test, hematoxylin-eosin staining and immunohistochemistry experiments. The results of the study showed that the AD model was successful; the S-E significantly enhanced long-term memory and spatial learning in AD rats. Meanwhile, S-E notably ameliorated Aβ25-35-induced cognitive impairment, improved hippocampal neuron morphology, decreased Aβ deposition in the hippocampus and mitigated inflammatory damage. We then analyzed serum and urine samples using UPLC-MS/MS to identify potential biomarkers and metabolic pathways. Metabolomic analysis revealed alterations in 40 serum metabolites and 38 urine metabolites following S-E treatment, predominantly affecting pathways related to taurine and hypotaurine metabolism, linoleic acid metabolism, α-linolenic acid metabolism, glycerophospholipid metabolism and arachidonic acid metabolism. This study elucidates the biochemical mechanism underlying AD and the metabolic pathway influenced by S-E, laying the groundwork for future clinical applications.

Tumor Homing Chimeric Peptide Rhomboids to Improve Photodynamic Performance by Inhibiting Therapy-Upregulated Cyclooxygenase-2

Negative therapeutic feedback of inflammation would extensively attenuate the antitumor effect of photodynamic therapy (PDT). In this work, tumor homing chimeric peptide rhomboids (designated as NP-Mel) are fabricated to improve photodynamic performance by inhibiting PDT-upregulated cyclooxygenase-2 (COX-2). The hydrophobic photosensitizer of protoporphyrin IX (PpIX) and palmitic acid are conjugated onto the neuropilin receptors (NRPs) targeting peptide motif (CGNKRTR) to obtain tumor homing chimeric peptide (Palmitic-K(PpIX)CGNKRTR), which can encapsulate the COX-2 inhibitor of meloxicam. The well dispersed NP-Mel not only improves the drug stability and reactive oxygen species (ROS) production ability, but also increase the breast cancer targeted drug delivery to intensify the PDT effect. In vitro and in vivo studies verify that NP-Mel will decrease the secretion of prostaglandin E2 (PGE2) after PDT treatment, inducing the downregulation of IL-6 and TNF-α expressions to suppress PDT induced inflammation. Ultimately, an improved PDT performance of NP-Mel is achieved without inducing obvious systemic toxicity, which might inspire the development of sophisticated nanomedicine in consideration of the feedback induced therapeutic resistance.

An Optimized Method for LC-MS-Based Quantification of Endogenous Organic Acids: Metabolic Perturbations in Pancreatic Cancer

Accurate and reliable quantification of organic acids with carboxylic acid functional groups in complex biological samples remains a major analytical challenge in clinical chemistry. Issues such as spontaneous decarboxylation during ionization, poor chromatographic resolution, and retention on a reverse-phase column hinder sensitivity, specificity, and reproducibility in multiple-reaction monitoring (MRM)-based LC-MS assays. We report a targeted metabolomics method using phenylenediamine derivatization for quantifying carboxylic acid-containing metabolites (CCMs). This method achieves accurate and sensitive quantification in various biological matrices, with recovery rates from 90% to 105% and CVs ≤ 10%. It shows linearity from 0.1 ng/mL to 10 µg/mL with linear regression coefficients of 0.99 and LODs as low as 0.01 ng/mL. The library included a wide variety of structurally variant CCMs such as amino acids/conjugates, short- to medium-chain organic acids, di/tri-carboxylic acids/conjugates, fatty acids, and some ring-containing CCMs. Comparing CCM profiles of pancreatic cancer cells to normal pancreatic cells identified potential biomarkers and their correlation with key metabolic pathways. This method enables sensitive, specific, and high-throughput quantification of CCMs from small samples, supporting a wide range of applications in basic, clinical, and translational research.

Gαz-independent and -dependent Improvements With EPA Supplementation on the Early Type 1 Diabetes Phenotype of NOD Mice

Prostaglandin E2 (PGE2) is a key mediator of inflammation and is derived from the omega-6 polyunsaturated fatty acid, arachidonic acid (AA). In the β-cell, the PGE2 receptor, Prostaglandin EP3 receptor (EP3), is coupled to the unique heterotrimeric G protein alpha subunit, Gɑz to reduce the production of cyclic adenosine monophosphate (cAMP), a key signaling molecule that activates β-cell function, proliferation, and survival pathways. Nonobese diabetic (NOD) mice are a strong model of type 1 diabetes (T1D), and NOD mice lacking Gɑz are protected from hyperglycemia. Therefore, limiting systemic PGE2 production could potentially improve both the inflammatory and β-cell dysfunction phenotype of T1D. Here, we sought to evaluate the effect of eicosapentaenoic acid (EPA) feeding, which limits PGE2 production, on the early T1D phenotype of NOD mice in the presence and absence of Gαz. Wild-type and Gαz knockout NOD mice were fed a control or EPA-enriched diet for 12 weeks, beginning at age 4 to 5 weeks. Oral glucose tolerance, splenic T-cell populations, islet cytokine/chemokine gene expression, islet insulitis, measurements of β-cell mass, and measurements of β-cell function were quantified. EPA diet feeding and Gɑz loss independently improved different aspects of the early NOD T1D phenotype and coordinated to alter the expression of certain cytokine/chemokine genes and enhance incretin-potentiated insulin secretion. Our results shed critical light on the Gαz-dependent and -independent effects of dietary EPA enrichment and provide a rationale for future research into novel pharmacological and dietary adjuvant therapies for T1D.

The calcineurin-NFATc pathway modulates the lipid mediators in BAL fluid extracellular vesicles, thereby regulating microvascular endothelial cell barrier function

Extracellular vesicles mediate intercellular communication by transporting biologically active macromolecules. Our prior studies have demonstrated that the nuclear factor of activated T cell cytoplasmic member 3 (NFATc3) is activated in mouse pulmonary macrophages in response to lipopolysaccharide (LPS). Inhibition of NFATc3 activation by a novel cell-permeable calcineurin peptide inhibitor CNI103 mitigated the development of acute lung injury (ALI) in LPS-treated mice. Although pro-inflammatory lipid mediators are known contributors to lung inflammation and injury, it remains unclear whether the calcineurin-NFATc pathway regulates extracellular vesicle (EV) lipid content and if this content contributes to ALI pathogenesis. In this study, EVs from mouse bronchoalveolar lavage fluid (BALF) were analyzed for their lipid mediators by liquid chromatography in conjunction with mass spectrometry (LC-MS/MS). Our data demonstrate that EVs from LPS-treated mice contained significantly higher levels of arachidonic acid (AA) metabolites, which were found in low levels by prior treatment with CNI103. The catalytic activity of lung tissue cytoplasmic phospholipase A2 (cPLA2) increased during ALI, correlating with an increased amount of arachidonic acid (AA) in the EVs. Furthermore, ALI is associated with increased expression of cPLA2, cyclooxygenase 2 (COX2), and lipoxygenases (5-LOX, 12-LOX, and 15-LOX) in lung tissue, and pretreatment with CNI103 inhibited the catalytic activity of cPLA2 and the expression of cPLA2, COX, and LOX transcripts. Furthermore, co-culture of mouse pulmonary microvascular endothelial cell (PMVEC) monolayer and NFAT-luciferase reporter macrophages with BALF EVs from LPS-treated mice increased the pulmonary microvascular endothelial cell (PMVEC) monolayer barrier permeability and luciferase activity in macrophages. However, EVs from CNI103-treated mice had no negative impact on PMVEC monolayer barrier integrity. In summary, BALF EVs from LPS-treated mice carry biologically active NFATc-dependent, AA-derived lipids that play a role in regulating PMVEC monolayer barrier function.

Broussonin E against acute respiratory distress syndrome: the potential roles of anti-inflammatory

We applied network pharmacology and molecular docking analyses to study the efficacy of Broussonin E (BRE) in acute respiratory distress syndrome (ARDS) treatment and to determine the core components, potential targets, and mechanism of action of BRE. The SwissTargetprediction and SEA databases were used to predict BRE targets, and the GeneCards and OMIM databases were used to predict ARDS-related genes. The drug targets and disease targets were mapped to obtain an intersecting drug target gene network, which was then uploaded into the String database for protein-protein interaction network analysis. The intersecting gene was also uploaded into the DAVID database for gene ontology enrichment analysis and Kyoto encyclopedia of genes and genomes pathway analysis. Molecular docking analysis was performed to verify the interaction of BRE with the key targets. Finally, to validate the experiment in vivo, we established an oleic acid-induced ARDS rat model and evaluated the protective effect of BRE on ARDS by histological evaluation and enzyme-linked immunosorbent assay. Overall, 79 targets of BRE and 3974 targets of ARDS were predicted, and 79 targets were obtained after intersection. Key genes such as HSP90AA1, JUN, ESR1, MTOR, and PIK3CA play important roles in the nucleus and cytoplasm by regulating the tumor necrosis factor, nuclear factor-κB, and PI3K-Akt signaling pathways. Molecular docking results showed that small molecules of BRE could freely bind to the active site of the target proteins. In vivo experiments showed that BRE could reduce ARDS-related histopathological changes, release of inflammatory factors, and infiltration of macrophages and oxidative stress reaction. BRE exerts its therapeutic effect on ARDS through target and multiple pathways. This study also predicted the potential mechanism of BRE on ARDS, which provides the theoretical basis for in-depth and comprehensive studies of BRE treatment on ARDS.

Montelukast Influence on Lung in Experimental Diabetes

Background and Objectives: The influence of montelukast (MK), an antagonist of cysLT1 leukotriene receptors, on lung lesions caused by experimental diabetes was studied. Materials and Methods: The study was conducted on four groups of six adult male Wistar rats. Diabetes was produced by administration of streptozotocin 65 mg/kg ip. in a single dose. Before the administration of streptozotocin, after 72 h, and after 8 weeks, the serum values of glucose, SOD, MDA, and total antioxidant capacity (TAS) were determined. After 8 weeks, the animals were anesthetized and sacrificed, and the lungs were harvested and examined by optical microscopy. Pulmonary fibrosis, the extent of lung lesions, and the lung wet-weight/dry-weight ratio were evaluated. Results: The obtained results showed that MK significantly reduced pulmonary fibrosis (3.34 ± 0.41 in the STZ group vs. 1.73 ± 0.24 in the STZ+MK group p < 0.01) and lung lesion scores and also decreased the lung wet-weight/dry-weight (W/D) ratio. SOD and TAS values increased significantly when MK was administered to animals with diabetes (77.2 ± 11 U/mL in the STZ group vs. 95.7 ± 13.3 U/mL in the STZ+MK group, p < 0.05, and 25.52 ± 2.09 Trolox units in the STZ group vs. 33.29 ± 1.64 Trolox units in the STZ+MK group, respectively, p < 0.01), and MDA values decreased. MK administered alone did not significantly alter any of these parameters in normal animals. Conclusions: The obtained data showed that by blocking the action of peptide leukotrienes on cysLT1 receptors, montelukast significantly reduced the lung lesions caused by diabetes. The involvement of these leukotrienes in the pathogenesis of fibrosis and other lung diabetic lesions was also demonstrated.

Can essential fatty acids (EFAs) prevent and ameliorate post-COVID-19 long haul manifestations?

It is hypothesized that COVID-19, post-COVID and post-mRNA COVID-19 (and other related) vaccine manifestations including "long haul syndrome" are due to deficiency of essential fatty acids (EFAs) and dysregulation of their metabolism. This proposal is based on the observation that EFAs and their metabolites can modulate the swift immunostimulatory response of SARS-CoV-2 and similar enveloped viruses, suppress inappropriate cytokine release, possess cytoprotective action, modulate serotonin and bradykinin production and other neurotransmitters, inhibit NF-kB activation, regulate cGAS-STING pathway, modulate gut microbiota, inhibit platelet activation, regulate macrophage and leukocyte function, enhance wound healing and facilitate tissue regeneration and restore homeostasis. This implies that administration of EFAs could be of benefit in the prevention and management of COVID-19 and its associated complications.

Research on the metabolic regulation mechanism of Yangyin Qingfei decoction plus in severe pneumonia caused by Mycoplasma pneumoniae in mice

Introduction: With amazing clinical efficacy, Yangyin Qingfei Decoction Plus (YQDP), a well-known and age-old Chinese compound made of ten Chinese botanical drugs, is utilized in clinical settings to treat a range of respiratory conditions. This study examines the impact of Yangyin Qingfei Decoction (YQDP) on lung tissue metabolic products in severe Mycoplasma pneumoniae pneumonia (SMPP) model mice and examines the mechanism of YQDP in treating MP infection using UPLC-MS/MS technology. Methods: YQDP's chemical composition was ascertained by the use of Agilent 1260 Ⅱ high-performance liquid chromatography. By using a nasal drip of 1010 CCU/mL MP bacterial solution, an SMPP mouse model was created. The lung index, pathology and ultrastructural observation of lung tissue were utilized to assess the therapeutic effect of YQDP in SMPP mice. Lung tissue metabolites were found in the normal group, model group, and YQDP group using UPLC-MS/MS technology. Using an enzyme-linked immunosorbent test (ELISA), the amount of serum inflammatory factors, such as interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α), was found. Additionally, the protein expression of PI3K, P-PI3K, AKT, P-AKT, NF-κB, and P-NF-κB was found using Western blot. Results: The contents of chlorogenic acid, paeoniflorin, forsythrin A, forsythrin, and paeonol in YQDP were 3.480 ± 0.051, 3.255 ± 0.040, 3.612 ± 0.017, 1.757 ± 0.031, and 1.080 ± 0.007 mg/g respectively. YQDP can considerably lower the SMPP mice's lung index (p < 0.05). In the lung tissue of YQDP groups, there has been a decrease (p < 0.05) in the infiltration of inflammatory cells at varying concentrations in the alveoli compared with the model group. A total of 47 distinct metabolites, including choline phosphate, glutamyl lysine, L-tyrosine, 6-thioinosine, Glu Trp, 5-hydroxydecanoate, etc., were linked to the regulation of YQDP, according to metabolomics study. By controlling the metabolism of porphyrins, pyrimidines, cholines, fatty acids, sphingolipids, glycerophospholipids, ferroptosis, steroid hormone biosynthesis, and unsaturated fatty acid biosynthesis, enrichment analysis suggested that YQDP may be used to treat SMPP. YQDP can lower the amount of TNF-α and IL-6 in model group mice as well as downregulate P-PI3K, P-AKT, and P-NF-κB expression (p < 0.05). Conclusion: A specific intervention effect of YQDP is observed in SMPP model mice. Through the PI3K/Akt/NF-κB signaling pathways, YQDP may have therapeutic benefits by regulating the body's metabolism of α-Linoleic acid, sphingolipids, glycerophospholipids, arachidonic acid, and the production of unsaturated fatty acids.

Harnessing anti-inflammatory pathways and macrophage nano delivery to treat inflammatory and fibrotic disorders

Targeting specific organs and cell types using nanotechnology and sophisticated delivery methods has been at the forefront of applicative biomedical sciences lately. Macrophages are an appealing target for immunomodulation by nanodelivery as they are heavily involved in various aspects of many diseases and are highly plastic in their nature. Their continuum of functional "polarization" states has been a research focus for many years yielding a profound understanding of various aspects of these cells. The ability of monocyte-derived macrophages to metamorphose from pro-inflammatory to reparative and consequently to pro-resolving effectors has raised significant interest in its therapeutic potential. Here, we briefly survey macrophages' ontogeny and various polarization phenotypes, highlighting their function in the inflammation-resolution shift. We review their inducing mediators, signaling pathways, and biological programs with emphasis on the nucleic acid sensing-IFN-I axis. We also portray the polarization spectrum of macrophages and the characteristics of their transition between different subtypes. Finally, we highlighted different current drug delivery methods for targeting macrophages with emphasis on nanotargeting that might lead to breakthroughs in the treatment of wound healing, bone regeneration, autoimmune, and fibrotic diseases.

LC-MS based untargeted metabolomics studies of the metabolic response of Ginkgo biloba extract on arsenism patients

Arsenic is an environmentally ubiquitous toxic metalloid. Chronic exposure to arsenic may lead to arsenicosis, while no specific therapeutic strategies are available for the arsenism patients. And Ginkgo biloba extract (GBE) exhibited protective effect in our previous study. However, the mechanisms by which GBE protects the arsenism patients remain poorly understood. A liquid chromatography-mass spectrometry (LC-MS) based untargeted metabolomics analysis was used to study metabolic response in arsenism patients upon GBE intervention. In total, 39 coal-burning type of arsenism patients and 50 healthy residents were enrolled from Guizhou province of China. The intervention group (n = 39) were arsenism patients orally administered with GBE (three times per day) for continuous 90 days. Plasma samples from 50 healthy controls (HC) and 39 arsenism patients before and after GBE intervention were collected and analyzed by established LC-MS method. Statistical analysis was performed by MetaboAnalyst 5.0 to identify differential metabolites. Multivariate analysis revealed a separation in arsenism patients between before (BG) and after GBE intervention (AG) group. It was observed that 35 differential metabolites were identified between BG and AG group, and 30 of them were completely or partially reversed by GBE intervention, with 14 differential metabolites significantly up-regulated and 16 differential metabolites considerably down-regulated. These metabolites were involved in promoting immune response and anti-inflammatory functions, and alleviating oxidative stress. Taken together, these findings indicate that the GBE intervention could probably exert its protective effects by reversing disordered metabolites modulating these functions in arsenism patients, and provide insights into further exploration of mechanistic studies.

Association between dietary inflammatory index with all-cause and cardiovascular disease mortality among older US adults: A longitudinal cohort study among a nationally representative sample

OBJECTIVE

To investigate the association between DII with all-cause and cardiovascular disease (CVD) mortality among older adults in the U.

S METHODS

This prospective cohort study included older adults with complete DII data and mortality data from the National Health and Nutrition Examination Survey (NHANES) 2001-2018. Mortality outcomes were linked to National Death Index records through 31 December 2019. The multivariate Cox proportional hazards models were performed to evaluate the association between DII and mortality. Restricted cubic spline analyses were used to examine the nonlinear association of DII with all-cause and CVD mortality.

RESULTS

During the median follow-up date of 6.7 years, 4446 all-cause deaths were documented among 10,827 representative older adults, including 1230 CVD deaths. After multivariate adjustment, linear relationships between DII with all-cause mortality (P non-linear = 0.17) and non-linear relationship between DII with CVD mortality (P non-linear = 0.04) were observed. Compared to participants with the lowest quartile of DII scores (-5.28 to≤0.43), the multivariate-adjusted HRs and 95 %CI for participants with higher DII scores were 1.19 (Q2, 95 %CI: 1.08-1.31), 1.28 (Q3, 95 %CI: 1.14-1.44), 1.30 (Q4, 95 %CI: 1.17-1.44) for all-cause mortality (P trend <0.001) and 1.19 (Q2, 95 %CI: 0.99-1.43), 1.34 (Q3, 95 %CI: 1.10-1.62), 1.30 (Q4, 95 %CI: 1.06-1.58) for CVD mortality (P trend < 0.01), respectively.

CONCLUSIONS

In the representative sample of older adults in the U.S, higher DII scores were associated with increased risks of all-cause and CVD mortality.

Microarray analysis identifies lncFirre as a potential regulator of obesity-related acute lung injury

AIMS

The inflammatory response in acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is heightened in obesity. The aim of this study was to investigate whether lncRNAs are involved in the effects of obesity on acute lung injury and to find possible effector lncRNAs.

MAIN METHODS

Microarray analysis was used to assess the transcriptional profiles of lncRNAs and mRNAs in lung tissues from normal (CON), high-fat diet induced obese (DIO), and obese ALI mice (DIO-ALI). GO and KEGG analyses were employed to explore the biological functions of differentially expressed genes. A lncRNA-mRNA co-expression network was constructed to identify specific lncRNA. Lung tissues and peripheral blood samples from patients with obesity and healthy lean donors were utilized to confirm the expression characteristics of lncFirre through qRT-PCR. lncFirre was knocked down in MH-S macrophages to explore its function. ELISA and Griess reagent kit were used to detect PGE2 and NO. Flow cytometry was used to detect macrophages polarization.

KEY FINDINGS

There were 475 lncRNAs and 404 mRNAs differentially expressed between DIO and CON, while 1348 lncRNAs and 1349 mRNAs between DIO-ALI and DIO. Obesity increased lncFirre expression in both mice and patients, and PA elevated lncFirre in MH-S. PA exacerbated the inflammation and proinflammatory polarization of MH-S induced by LPS. LncFirre knockdown inhibited the secretion of PGE2 and NO, M1 differentiation while promoted the M2 differentiation in PA and LPS co-challenged MH-S.

SIGNIFICANCE

Interfering with lncFirre effectively inhibit inflammation in MH-S, lncFirre can serve as a promising target for treating obesity-related ALI.

Metabolomics study of graphene nuangong acupoint plaster for primary dysmenorrhea

Primary dysmenorrhea is a common gynecological disease with typical clinical symptoms and diverse treatment methods. Acupoint patch therapy is one of the traditional external treatments of traditional Chinese medicine, with a long history, and has been widely used in the treatment of many diseases in China. Graphene nuangong acupoint plaster (GNGAP) developed based on traditional acupoints and new materials have been used in the clinical treatment of primary dysmenorrhea, and satisfactory therapeutic effects have been achieved. However, the underlying mechanisms of GNGAP still need further investigation. In this study, we used estradiol benzoate combined with oxytocin intraperitoneally to establish dysmenorrhea model rats, and observed the torsion response, uterine organ coefficients, prostaglandin levels and metabolite changes of rats with dysmenorrhea model after the intervention of GNGAP, to elucidate the mechanism of the effect of GNGAP. Compared with normal rats, the dysmenorrhea model rats exhibited increased writhing response and latency time, increased uterine organ coefficient, and significant changes in 79 metabolites. Twenty-three significantly enriched pathways were discovered, including amino acid metabolism, arachidonic acid metabolism, pyrimidine metabolism, and ovarian steroidogenesis, which may be involved in the pathogenesis of primary dysmenorrhea. Compared with the model group, the torsion response, latency time and uterine organ coefficient of rats in the acupoint patch group were significantly improved, and nine uterine metabolites were significantly altered, among which metabolites such as 4-pyridoxic acid, d-glucarate and Phenol were identified as potential biomarkers for the therapeutic effects of GNGAP. Vitamin B6 metabolism, Ascorbate and aldarate metabolism and Tyrosine metabolism were enriched in nine metabolic pathways. These findings contribute to the screening study of potential pathological metabolic pathways in primary dysmenorrhea. Additionally, they reveal the biological effects of GNGAP in the treatment of primary dysmenorrhea at the metabolite level.

Scd-1 deficiency promotes the differentiation of CD8+ T effector

The impact of various fatty acid types on adaptive immunity remains uncertain, and their roles remain unelucidated. Stearoyl-CoA desaturase (Scd) is a Δ-9 desaturase, which is a key rate-limiting enzyme for the conversion of saturated fatty acids (SFA) to monounsaturated fatty acids (MUFA) in the fatty acid de novo synthesis. Scd-1 converts stearic acid (SA) and palmitic acid (PA) to oleic acid (OA) and palmitoleic acid (PO), respectively. In this study, through a series of experiments, we showed that Scd-1 and its resulting compound, OA, have a substantial impact on the transformation of CD8+ naïve T cells into effector T cells. Inactivation of Scd-1 triggers the specialization of CD8+ T cells into the Teff subset, enhancing the effector function and mitochondrial metabolism of Teff cells, and OA can partially counteract this. A deeper understanding of lipid metabolism in immune cells and its impact on cell function can lead to new therapeutic approaches for controlling the immune response and improving prognosis.

The mitochondrial thiolase ACAT1 regulates monocyte/macrophage type I interferon via epigenetic control

Lipid-derived acetyl-CoA is shown to be the major carbon source for histone acetylation. However, there is no direct evidence demonstrating lipid metabolic pathway contribututions to this process. Mitochondrial acetyl-CoA acetyltransferase 1 (ACAT1) catalyzes the final step of ß-oxidation, the aerobic process catabolizing fatty acids (FA) into acetyl-CoA. To investigate this in the context of immunometabolism, we generated macrophage cell line lacking ACAT1. 13C-carbon tracing combined with mass spectrometry confirmed incorporation of FA-derived carbons into histone H3 and this incorporation was reduced in ACAT1 KO macrophage cells. RNA-seq identified a subset of genes downregulated in ACAT1 KO cells including STAT1/2 and interferon stimulated genes (ISGs). CHIP analysis demonstrated reduced acetyl-H3 binding to STAT1 promoter/enhancer regions. Increasing histone acetylation rescued STAT1/2 expression in ACAT1 KO cells. Concomitantly, ligand triggered IFNβ release was blunted in ACAT1 KO cells and rescued by reconstitution of ACAT1. Furthermore, ACAT1 promotes FA-mediated histone acetylation in an acetylcarnitine shuttle-dependent manner. In patients with obesity, levels of ACAT1 and histone acetylation are abnormally elevated. Thus, our study identified a novel link between ACAT1 mediated FA metabolism and epigenetic modification on STAT1/2 that uncovers a regulatory role of lipid metabolism in innate immune signaling and opens novel avenues for interventions in human diseases such as obesity.

BML-111 inhibit H2O2-induced pyroptosis and osteogenic dysfunction of human periodontal ligament fibroblasts by activating the Nrf2/HO-1 pathway

BACKGROUND

Periodontitis is a common and harmful chronic inflammatory oral disease, characterized by the destruction of periodontal soft and hard tissues. The NLRP3 inflammasome-related pyroptosis and human periodontal ligament fibroblasts (hPDLFs) osteogenic dysfunction are involved in its pathogenesis. Studies have shown that lipoxin A4 is an endogenous anti-inflammatory mediator and BML-111 is a lipoxin A4 analog, which was found to have potent and durable anti-inflammatory effects in inflammatory diseases, but the mechanism remains unclear. The purpose of this study was to investigate whether BML-111 inhibits H2O2-induced dysfunction of hPDLFs, attenuates inflammatory responses, and identifies the underlying mechanisms.

METHODS

The oxidative stress model was established with H2O2, and the cell proliferation activity was measured by CCK-8. ALP staining and alizarin red staining were used to detect the osteogenic differentiation capacity of cells; flow cytometry and ELISA were used to detect cell pyroptosis; we explored the effect of BML-111 on hPDLFs under oxidative stress by analyzing the results of PCR and Western blotting. The Nrf2 inhibitor ML385 was added to further identify the target of BML-111 and clarify its mechanism.

RESULTS

BML-111 can alleviate the impaired cell proliferation viability induced by H2O2. H2O2 treatment can induce NLRP3 inflammasome-related pyroptosis, impairing the osteogenic differentiation capacity of hPDLFs. BML-111 can effectively alleviate H2O2-induced cellular dysfunction by activating the Nrf2/HO-1 signaling pathway.

CONCLUSION

The results of this study confirmed the beneficial effects of BML-111 on H2O2-induced NLRP3 inflammasome-related pyroptosis in hPDLFs, and BML-111 could effectively attenuate the impaired osteogenic differentiation function. This beneficial effect is achieved by activating the Nrf2/HO-1 signaling pathway, therefore, our results suggest that BML-111 is a potential drug for the treatment of periodontitis.

PGE2 Potentiates Orai1-Mediated Calcium Entry Contributing to Peripheral Sensitization

Peripheral sensitization is one of the primary mechanisms underlying the pathogenesis of chronic pain. However, candidate molecules involved in peripheral sensitization remain incompletely understood. We have shown that store-operated calcium channels (SOCs) are expressed in the dorsal root ganglion (DRG) neurons. Whether SOCs contribute to peripheral sensitization associated with chronic inflammatory pain is elusive. Here we report that global or conditional deletion of Orai1 attenuates Complete Freund's adjuvant (CFA)-induced pain hypersensitivity in both male and female mice. To further establish the role of Orai1 in inflammatory pain, we performed calcium imaging and patch-clamp recordings in wild-type (WT) and Orai1 knockout (KO) DRG neurons. We found that SOC function was significantly enhanced in WT but not in Orai1 KO DRG neurons from CFA- and carrageenan-injected mice. Interestingly, the Orai1 protein level in L3/4 DRGs was not altered under inflammatory conditions. To understand how Orai1 is modulated under inflammatory pain conditions, prostaglandin E2 (PGE2) was used to sensitize DRG neurons. PGE2-induced increase in neuronal excitability and pain hypersensitivity was significantly reduced in Orai1 KO mice. PGE2-induced potentiation of SOC entry (SOCE) was observed in WT, but not in Orai1 KO DRG neurons. This effect was attenuated by a PGE2 receptor 1 (EP1) antagonist and mimicked by an EP1 agonist. Inhibition of Gq/11, PKC, or ERK abolished PGE2-induced SOCE increase, indicating PGE2-induced SOCE enhancement is mediated by EP1-mediated downstream cascade. These findings demonstrate that Orai1 plays an important role in peripheral sensitization. Our study also provides new insight into molecular mechanisms underlying PGE2-induced modulation of inflammatory pain.Significance Statement Store-operated calcium channel (SOC) Orai1 is expressed and functional in dorsal root ganglion (DRG) neurons. Whether Orai1 contributes to peripheral sensitization is unclear. The present study demonstrates that Orai1-mediated SOC function is enhanced in DRG neurons under inflammatory conditions. Global and conditional deletion of Orai1 attenuates complete Freund's adjuvant (CFA)-induced pain hypersensitivity. We also demonstrate that prostaglandin E2 (PGE2) potentiates SOC function in DRG neurons through EP1-mediated signaling pathway. Importantly, we have found that Orai1 deficiency diminishes PGE2-induced SOC function increase and reduces PGE2-induced increase in neuronal excitability and pain hypersensitivity. These findings suggest that Orai1 plays an important role in peripheral sensitization associated with inflammatory pain. Our study reveals a novel mechanism underlying PGE2/EP1-induced peripheral sensitization. Orai1 may serve as a potential target for pathological pain.