Prostaglandins and leukotrienes: advances in eicosanoid biology

Preliminary Metabolomics Data Reveals Lipid Metabolism and Oxidative Stress Metabolites as Potential Biomarkers for Patent Ductus Arteriosus

Patent ductus arteriosus (PDA) is a common congenital heart defect in preterm infants and is associated with significant morbidity. Early diagnosis is crucial but challenging due to nonspecific clinical symptoms. This study aims to identify potential metabolomic biomarkers for early detection of PDA using human cord blood. A prospective cross-sectional study was conducted involving 45 preterm infants between 230/6 and 316/7 weeks of gestation. The diagnosis of hemodynamically significant PDA (hsPDA) was based on echocardiographic findings after 48 h, showing a left atrium-to-aortic root ratio > 1.5 and/or a ductus diameter > 1.5 mm. Untargeted metabolomics analysis was performed on cord blood plasma samples using quadrupole time-of-flight liquid chromatography-mass spectrometry (Q-TOF LC/MS). Data were processed for metabolites that differed between groups. Twenty infants with hsPDA formed the study group, 25 controls. Out of 4237 detected peaks, 40 showed statistically significant differences (fold change > 1.5,p < 0.05). Among these, 15 metabolites were potentially clinically relevant. Key findings included decreased levels of guanidino acetic acid, S-adenosylmethionine, and ceramides and increased levels of docosahexaenoic acid, arachidonic acid, and cholesterol-related molecules in the PDA group. The study reveals significant metabolic alterations in lipid metabolism and oxidative stress-related pathways in PDA infants. Further targeted metabolomics studies are warranted to validate and explore clinical applications.

Enteric tuft cell inflammasome activation drives NKp46+ILC3 IL22 via PGD2 and inhibits Salmonella

To distinguish pathogens from commensals, the intestinal epithelium employs cytosolic innate immune sensors. Activation of the NAIP-NLRC4 inflammasome initiates extrusion of infected intestinal epithelial cells (IEC) upon cytosolic bacterial sensing. We previously reported that activation of the inflammasome in tuft cells, which are primarily known for their role in parasitic infections, leads to the release of prostaglandin D2 (PGD2). We observe that NAIP-NLRC4 inflammasome activation in tuft cells leads to an antibacterial response with increased IL-22 and antimicrobial protein levels within the small intestine, which is dependent on PGD2 signaling. A NKp46+ subset of ILC3 expresses the PGD2 receptor CRTH2 and is the source of the increased IL-22. Inflammasome activation in tuft cells also leads to better control of Salmonella Typhimurium in the distal small intestine. However, tuft cells in the cecum and colon are dispensable for antibacterial immunity. These data support that intestinal tuft cells can also induce antibacterial responses, possibly in a tissue-specific manner.

"Methyl jasmonate: bridging plant defense mechanisms and human therapeutics"

A volatile organic substance produced from jasmonic acid, methyl jasmonate (MJ/MeJA), is an important plant hormone involved in stress responses and plant defense. Apart from its role in plants, MJ has garnered significant attention because of its pharmacological effects and possible therapeutic use in human health. This thorough analysis looks into the many biological actions of MJ, such as its antioxidant, anti-inflammatory, and anti-cancer effects. The underlying mechanism of these actions is examined, emphasizing MJ's ability to modulate important signaling pathways, cause cancer cells to undergo apoptosis, and boost immunological responses. Furthermore, MJ's capacity to manage long-term illnesses like cancer and neurological conditions like Parkinson's and Alzheimer's is examined. Preclinical and clinical research are beginning to provide evidence that MJ may be a useful medicinal drug. Nevertheless, more research is needed to fully understand its mode of action, enhance its administration methods, and evaluate its efficacy and safety in humans. This review highlights MJ's therapeutic promise and supports earlier research into its pharmacological capabilities and possible medical applications. This abstract highlights methyl jasmonate's pharmacological effects and therapeutic potential by providing a concise overview of the main topics covered in a thorough review.

Unraveling the molecular dynamics of wound healing: integrating spatially resolved lipidomics and temporally resolved proteomics

Understanding the spatial-temporal molecular dynamics of wound healing is crucial for devising effective treatments. Three-dimensional mass spectrometry imaging (3D MSI) enables the comprehensive visualization of molecular distribution throughout skin layers, offering valuable insights into the wound healing process. However, traditional 3D MSI often faces challenges in maintaining data integrity and accurate image registration in the third dimension. To address this, we employed infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI), a hybrid ambient ionization technique capable of sequential imaging through consecutive ablation events for precise 3D image reconstruction. Herein, 3D IR-MALDESI MSI was used to compare the lipidome of fresh-frozen wound samples at three stages of wound healing (inflammation, proliferation, and remodeling) with the healthy skin of SKH- 1 mice. Supplementing this data with a refined LC-MS-based proteomics protocol on selected wound biopsies, our integrated approach deepens our understanding of the molecular intricacies inherent in tissue regeneration.

Phagocytosis is differentially regulated by LPS in M1- and M2-like macrophages via PGE2 formation and EP4 signaling

Phagocytosis is a key process in human innate immune response. Human macrophages are important phagocytes engulfing and neutralizing pathogens and cell debris. In addition, they modulate the inflammatory process by releasing cytokines and lipid mediators. However, the link between oxylipins and phagocytosis in different macrophage phenotypes remains poorly understood. In order to better understand the link between phagocytosis and the arachidonic acid (ARA) cascade, we established a phagocytosis assay in primary human 'inflammatory' M1- and 'anti-inflammatory' M2-like macrophages from peripheral blood mononuclear cells (PBMC), representing extremes of macrophage phenotypes. The branches of the ARA cascade were investigated by quantitative targeted proteomics and metabolomics. M1-like macrophages show a higher abundance of cyclooxygenase (COX)-2 and its products particularly after LPS stimulus compared to M2-like macrophages. LPS increased phagocytosis in M2-like, but not in M1-like macrophages. We demonstrate that the COX product prostaglandin E2 (PGE2) modulates the differential effects of LPS on phagocytosis: Via the EP4 receptor PGE2 signaling suppresses phagocytosis in primary human macrophages. Thus, blockage of COX, e.g. by non-steroidal anti-inflammatory drugs (NSAID), leads to an increase of phagocytosis also in 'inflammatory' M1-like macrophages. This supports the well-described anti-inflammatory effects of these drugs and underscores the importance of the link between the COX branch of the ARA cascade and the regulation of phagocytosis in human macrophages.

Profiling the Anti-Photoaging Impact of Titanium Dioxide and Zinc Oxide Nanoparticles: A Focus on Signaling Pathways

Inorganic nanoparticles are known to protect skin from ultraviolet rays (UVR) and delay photoaging. However, the photoprotective effects of these nanoparticles have not been broadly analyzed at a genetic level. The study objectives are as follows: (1) to investigate how UV-only and complete solar light can affect signaling pathways and genes related to photoaging in human dermal fibroblasts; (2) to investigate how TiO2 and ZnO nanoparticles provide photoprotection at a genetic level. RNAseq identified pathways and genes that were significantly affected by both irradiation conditions. Extracellular matrix (ECM) remodeling, inflammation, and cell cycle-related genes were subsequently validated by qPCR. The photoprotective properties of < 100 nm TiO2 and ZnO dispersions at a 25% active level were analyzed through quantitative differences in the irradiation-induced expression of these genes. There were < 15 signaling pathways affected by UV and complete solar light (p-value (-log10) > 1). Significant differences in gene expression following irradiation were found in MMP1, MMP3, PTGS1, PTGES, MDM2, CDKN1A, and CCNE2 (p ≤ 0.05) through qPCR. TiO2 and ZnO minimized the irradiation-induced expression of genes involved in the inhibition of matrix metalloproteinases, prostanoid biosynthesis, and cell cycle pathways. Photoprotection was best observed in cell cycle-related genes, showing expression differences of up to 74% (p ≤ 0.0001). However, no distinct differences in photoprotection between TiO2 and ZnO were found. The findings from this study serve as a framework for future optimization and development of inorganic sunscreen formulations to target genes that contribute to different aspects of skin aging.

Identification, evolution, functional characterization and expression pattern of a fatty acyl desaturase (fads1) gene in Chinese sturgeon (Acipenser sinensis)

Fatty acyl desaturases (Fads) are known to play critical roles in the biosynthesis of long-chain polyunsaturated fatty acids (LC-PUFAs) in fish species. To date, research on Fads in fish has predominantly focused on Fads2, while studies on Fads1 have been rarely reported. Acipenseriformes, commonly known as Chondrostei, are an ancient fish lineage with unique evolutionary history. However, the biological roles and evolutionary status of Fads1 in Chondrostei remain unclear, which constrains our understanding of the evolutionary processes shaping LC-PUFA biosynthesis in this lineage. In this study, we identified and characterized a fads1 gene from Chinese sturgeon (Acipenser sinensis), a critically endangered Chondrostei, using molecular cloning and multiple bioinformatic analyses. The spatio-temporal expression patterns, functional characteristics, and transcriptional regulation in response to dietary fatty acids were investigated. The coding sequence of the fads1 gene was 1317 bp in length, encoding a protein of 438 amino acids. Bioinformatic analyses suggested high conservation of fads genes across Chondrostei despite their complex evolutionary history. Functional characterization in yeast showed that Chinese sturgeon Fads1 exhibited Δ5 desaturation activity, efficiently converting 20:3n-6 to arachidonic acid (ARA) and 20:4n-3 to eicosapentaenoic acid (EPA). Fatty acid composition analysis indicated that Chinese sturgeon could biosynthesize LC-PUFAs when they are deficient in their diets. Taken together, these results suggest that fads1 plays a crucial role in LC-PUFA biosynthesis in Chinese sturgeon, which provides solid theoretical basis for dietary LC-PUFA requirement of Chinese sturgeon. Furthermore, our findings provide novel insights into evolutionary diversification of fads genes in fish species.

Discovery of novel microsomal prostaglandin E2 synthase 1 (mPGES-1) inhibitors by a structurally inspired virtual screening study

Prostaglandin (PG) E2 is a pro-inflammatory lipid mediator derived from the metabolism of arachidonic acid (AA) by cyclooxygenases (COX) and PGE2 synthases. Nonsteroidal anti-inflammatory drugs (NSAIDs), commonly used in the treatment of inflammation, nonselectively inhibit COX activity and decrease PGE2 production. However, these drugs cause gastrointestinal bleeding and several cardiovascular complications. Therefore, inhibiting microsomal PGE2 Synthase-1 (mPGES-1) to block PGE2 production downstream of COX is expected to yield safer and more effective treatments for inflammation, cancer, and cardiovascular diseases. At present, there are no mPGES-1 inhibitors available on the market, but ongoing research continuously evaluates new compounds in both preclinical and clinical stages. Here, we conducted a high throughput virtual screening campaign to discover novel mPGES-1 inhibitor scaffolds. This campaign utilized physicochemical filtering alongside both structure-aware ligand-based approaches (shape screening templates and pharmacophore models, which were generated based on the 3D binding modes of the co-crystallized mPGES-1 inhibitors) and structure-based strategies (refinement with docking and molecular dynamics). Thirty-four compounds were selected and biologically tested for mPGES-1 inhibition in a cell-free assay using microsomes from interleukin-1β-stimulated A549 cells as the source of mPGES-1. The most potent compound inhibited the remaining enzyme activity with an IC50 value of 6.46 μM in a cell-free assay for PGE2 production. We also compared the binding patterns of the most active compounds identified in this study with those of co-crystallized inhibitors using molecular dynamics simulations. This comparison underscored the crucial role of ionic interactions, π-π interactions, hydrogen bonds, and water bridges involving specific amino acids. Our results highlight the importance of these interaction networks within the binding cavity in various binding scenarios. Ultimately, the insights gained from this study could assist in designing and developing new mPGES-1 inhibitors.

Exploring the Mechanism of Action of Honeybran-Fried Cimicifuga Rhizoma in the Treatment of IBS-D Based on Metabolomics and Network Pharmacology

Honeybran-fried Cimicifuga Rhizoma (HBCR) is often used to treat prolonged diarrhea and prolapse of the anus, uterine prolapse, and gastric ptosis caused by spleen qi deficiency and the inability to elevate qi, and thus the lowering of middle qi. Rats were divided randomly into four groups. Fecal samples of rats in each group were subjected to metabolomics analysis. We identified the chemical components of HBCR using liquid chromatography-tandem mass spectrometry. We predicted the potential active components and key targets of HBCR using network pharmacology to construct a "drug-potential active ingredient-target-disease" network. The key targets screened by network pharmacology and differential metabolites screened by metabolomics analysis were subjected to combined pathway analysis. Pharmacodynamic indices showed that HBCR had a good therapeutic effect upon IBS-D. Metabolomics analysis revealed 26 differential metabolites in the treatment of IBS-D by HBCR. A total of 69 chemical components were identified, and 32 potential active components and 296 key targets were screened. Combination of metabolomics analysis and network pharmacology for joint pathway analysis revealed that the therapeutic effect of HBCR may be affected by the metabolism of linoleic acid, retinol, arachidonic acid, and tryptophan. HBCR had significant therapeutic effects in rats with IBS-D.

A Lipidomic Approach to Studying the Downregulation of Free Fatty Acids by Cytosolic Phospholipase A2 Inhibitors

Inhibitors of cytosolic phospholipase A2 (GIVA cPLA2) have received great attention, since this enzyme is involved in a number of inflammatory diseases, including cancer and auto-immune and neurodegenerative diseases. Traditionally, the effects of GIVA cPLA2 inhibitors in cells have been studied by determining the inhibition of arachidonic acid release. However, although to a lesser extent, GIVA cPLA2 may also hydrolyze glycerophospholipids, releasing other free fatty acids (FFAs), such as linoleic acid or oleic acid. In the present work, we applied a liquid chromatography-high-resolution mass spectrometry method to study the levels of intracellular FFAs, after treating cells with selected GIVA cPLA2 inhibitors. Six inhibitors belonging to different chemical classes were studied, using SH-SY5Y neuroblastoma cells as a model. This lipidomic approach revealed that treatment with each inhibitor created a distinct intracellular FFA profile, suggesting not only inhibitory potency against GIVA cPLA2, but also other parameters affecting the outcome. Potent inhibitors were found to reduce not only arachidonic acid, but also other long-chain FAs, such as adrenic or linoleic acid, even medium-chain FAs, such as caproic or caprylic acid, suggesting that GIVA cPLA2 inhibitors may affect FA metabolic pathways in general. The downregulation of intracellular FFAs may have implications in reprogramming FA metabolism in neurodegenerative diseases and cancer.

Chronic inflammation in obesity and neurodegenerative diseases: exploring the link in disease onset and progression

Obesity, a worldwide health emergency, is defined by excessive fat accumulation and significantly impacts metabolic health. In addition to its recognized association with cardiovascular disease, diabetes, and other metabolic illnesses, recent studies have revealed the connection between obesity and neurodegeneration. The main reason for this link is inflammation caused by the growth of fat tissue, which activates harmful processes that affect how the brain works. Fat tissue, particularly the fat around the organs, produces various substances that cause inflammation, such as cytokines (TNF-α, IL-6), adipokines (leptin, resistin), and free fatty acids. These chemicals cause low-grade, persistent systemic inflammation, which is becoming more widely acknowledged as a major factor in peripheral metabolic dysfunction and pathology of the central nervous system (CNS). Inflammatory signals in the brain cause neuroinflammatory reactions that harm neuronal structures, change neuroplasticity, and disrupt synaptic function. When obesity-related inflammation is present, the brain's resident immune cells, known as microglia, become hyperactivated, which can lead to the production of neurotoxic chemicals, which can cause neuronal death. This neuroinflammation exacerbates the negative effects of obesity on brain health and is linked to cognitive decline, Alzheimer's disease, and other neurodegenerative disorders. Moreover, the blood-brain barrier (BBB) exhibits increased permeability during inflammatory states, facilitating the infiltration of peripheral immune cells and cytokines into the brain, hence exacerbating neurodegeneration. Adipose tissue is a source of chronic inflammatory mediators, which are examined in this review along with the molecular pathways that connect inflammation brought on by obesity to neurodegeneration. Additionally, it addresses various anti-inflammatory treatment approaches, including lifestyle modifications, anti-inflammatory medications, and gut microbiota modulation, to lessen the metabolic and neurological effects of obesity. Recognizing the link between obesity and inflammation opens up new opportunities for early intervention and the development of targeted treatments to prevent or alleviate neurodegenerative disorders.

Engineering yeast for tailored fatty acid profiles

The demand for sustainable and eco-friendly alternatives to fossil and plant oil-derived chemicals has spurred interest in microbial production of lipids, particularly triacylglycerols, fatty acids, and their derivatives. Yeasts are promising platforms for synthesizing these compounds due to their high lipid accumulation capabilities, robust growth, and generally recognized as safe (GRAS) status. There is vast interest in fatty acid and triacylglycerol products with tailored fatty acid chain lengths and compositions, such as polyunsaturated fatty acids and substitutes for cocoa butter and palm oil. However, microbes naturally produce a limited set of mostly long-chain fatty acids, necessitating the development of microbial cell factories with customized fatty acid profiles. This review explores the capabilities of key enzymes involved in fatty acid and triacylglycerol synthesis, including fatty acid synthases, desaturases, elongases, and acyltransferases. It discusses factors influencing fatty acid composition and presents engineering strategies to enhance fatty acid synthesis. Specifically, we highlight successful engineering approaches to modify fatty acid profiles in triacylglycerols and produce tailored fatty acids, and we offer recommendations for host selection to streamline engineering efforts. KEY POINTS: • Detailed overview on all basic aspects of fatty acid metabolism in yeast • Comprehensive description of fatty acid profile tailoring in yeast • Extensive summary of applying tailored fatty acid profiles in production processes.

Pre-emptive Montelukast and Its Effect on Clinical Outcomes After Mandibular Third Molar Surgery: A Triple-blinded Randomized Controlled Trial

BACKGROUND

Cyclooxygenase inhibitors are well-studied for pain and swelling control after mandibular third molar extraction, while the lipoxygenase pathway and leukotriene receptor antagonists, like montelukast, remain less researched.

PURPOSE

The purpose of the study was to measure and compare postoperative pain relief from single pre-emptive doses of montelukast and etoricoxib.

STUDY DESIGN

The investigators conducted a triple-blinded, placebo-controlled randomized clinical trial and enrolled a sample of patients who presented to the All India Institute of Medical Sciences, Mangalagiri, between January 2023 and April 2023 for evaluation and management of impacted lower third molars. Patients with active inflammation or infection in the third molar region were excluded from the study.

PREDICTOR VARIABLE

The predictor variable was pre-emptive analgesic regimen: montelukast, etoricoxib, or a placebo, and subjects were randomly assigned to 3 groups.

OUTCOME VARIABLE(S)

The primary outcome variable was the intensity of postoperative pain, measured using an 11-point visual analog scale at 0, 2, 4, 6, 8, 10, 12, 24, 48, 72 hours, and 7 days postsurgery. Secondary outcome variables included changes in tissue tumor necrosis factor-alpha levels, the need for rescue analgesia, edema, and trismus.

COVARIATES

The study covariates included demographic and surgical characteristics.

ANALYSES

Bivariate analyses were conducted using the χ2 test or one-way ANOVA, while univariate analysis utilized repeated-measures ANOVA to assess outcome changes over time, followed by post-hoc comparisons for group differences. Statistical significance was set at P < .05.

RESULTS

Forty-eight participants were randomized into 3 equal groups of 16, with no statistically significant differences in clinicoradiographic or surgical characteristics (P > .2). At 2 hours postoperatively, the mean pain score was significantly lower in the etoricoxib group (2.19 ± 2.0) compared to the montelukast and placebo groups (3.06 ± 1.6 and 4.13 ± 1.9, respectively) (P = .01; 95% CI: -3.60 to -0.27). Repeated-measures ANOVA revealed a statistically significant interaction between time and treatment group (P = .008). Post hoc analysis showed significantly lower pain intensity at 2 hours in the etoricoxib group compared to the placebo group (P = .01; 95% CI: -3.60 to -0.27).

CONCLUSION

In third molar surgery, pre-emptive etoricoxib reduced postoperative pain, while montelukast decreased inflammation and modulated tumor necrosis factor-alpha levels. The results of the study do not support the use of the alternative pre-emptive analgesic regimens.

Anti-HBV activity of (R)-gentiandiol, a metabolite of Swertiamarin, in transgenic mice: Insights from non-targeted serum metabolomics

Swertiamarin, a predominant component in many traditional Chinese swertia herbs, shows significant anti-HBV activity clinically. (R)-gentiandiol and (S)-gentiandiol are the metabolites of swertiamarin in vivo. In this study, HBsAg, HBeAg and HBV-DNA were determined in liver tissue of HBV-transgenic C57BL/6NCrl mice to analyze anti-HBV activities of swertiamarin, (R)-gentiandiol and (S)-gentiandiol. It was found that HBsAg, HBeAg and HBV-DNA levels were significantly reduced in a dose-dependent manner when (R)-gentiandiol was administered at 1.5, 3 and 6 mg/kg. However, (S)-gentiandiol showed no anti-HBV activity at all. In addition, we also performed untargeted metabolomics to discover biomarkers and metabolic pathways of swertiamarin and (R)-gentiandiol in HBV-transgenic C57BL/6NCrl mice. A total of 15 candidate biomarkers were obtained. Meanwhile, the metabolic disorders including 8 metabolic pathways, such as taurine and hypotaurine metabolism were explored. Taurine and hypotaurine metabolism was the primary pathway for (R)-gentiandiol to regulate HBV-transgenic C57BL/6NCrl mice. It is the first time to clarify real active anti-HBV metabolites of swertiamarin, which can offer more insights into anti-HBV activities of swertia herbs, and bring novel ideas for new drug development in anti-HBV herbs.

Prostaglandins limit nuclear actin rod formation during Drosophila oogenesis

Expression of GFP-Actin results in nuclear actin rod formation during specific stages of Drosophila melanogaster oogenesis. Loss of prostaglandin (PG) synthesis and signaling results in an increased frequency of cells with nuclear actin rods; there are less rods per cell, but the rods are longer. These findings suggest that loss of PGs results in increased nuclear actin and are consistent with prior findings assessing the roles of PGs in modulating endogenous nuclear actin. Thus, GFP-Actin rod formation can be used as a tool to screen for new regulators of nuclear actin.

Immunoregulatory mechanisms of the arachidonic acid pathway in cancer

The arachidonic acid (AA) pathway promotes tumor progression by modulating the complex interactions between cancer and immune cells within the microenvironment. In this Review, we summarize the knowledge acquired thus far concerning the intricate mechanisms through which eicosanoids either promote or suppress the antitumor immune response. In addition, we will discuss the impact of eicosanoids on immune cells and how they affect responsiveness to immunotherapy, as well as potential strategies for manipulating the AA pathway to improve anticancer immunotherapy. Understanding the molecular pathways and mechanisms underlying the role played by AA and its metabolites in tumor progression may contribute to the development of more effective anticancer immunotherapies.

ZfpA-Dependent Quorum Sensing Shifts in Morphology and Secondary Metabolism in Aspergillus flavus

Development of the fungal pathogen Aspergillus flavus involves the balance of asexual spores (conidia) and overwintering hardened hyphal masses (sclerotia). This balance is achieved by an oxylipin-based density-dependent mechanism regulating the switch from sclerotia to conidia as population density increases in A. flavus. Here, we show the transcription factor ZfpA, required for normal oxylipin synthesis, regulates the morphology switch. ZfpA overexpression (OE::zfpA) accelerates the shift leading to increased conidial production and reduced sclerotial production under conditions normally supporting sclerotia formation. In contrast, zfpA deletion (ΔzfpA) produces more sclerotia than wild-type control. These morphology changes are coupled with changes in tissue-specific secondary metabolites. Specifically, the production of four sclerotial metabolites (oxyasparasone A, hydroxyaflatrem, aflavinine, and kotanin) decreases in OE::zfpA whereas the hyphal metabolite aspergillic acid is upregulated in this mutant. Chemical profiling of OE::zfpA compared to a double mutant where the aspergillic acid non-ribosomal synthetase was deleted in the OE::zfpA background confirmed synthesis of known aspergillic acid pathway products as well as putative Val-derived pyrazinones involved in metal chelation. These findings offer valuable insights into the quorum sensing networks connecting fungal development and tissue-specific secondary metabolite production.

Is Cytomegalovirus (CMV) Associated With Development of Posttransplant Psychosis? A Case Report and Review of the Literature

Cytomegalovirus (CMV) has a negative impact on overall posttransplant rehabilitation. While infection often manifests as gastrointestinal disease, pneumonitis, nephritis and others, it may be associated with psychotic symptoms. The role of CMV in etiology of schizophrenia has already been recognized but it was never described in the posttransplant psychosis. We present a case depicting development of psychosis 10 years post kidney transplantation associated with CMV disease.

A Multi-Omics Study of Neurodamage Induced by Growth-Stage Real-Time Air Pollution Exposure in Mice via the Microbiome-Gut-Brain Axis

Air pollution has been widely recognized as a risk factor for neurological disorders, and the gut microbiome may play a mediating role. However, current evidence remains limited. In this study, a mouse model was employed with continuous exposure to real-time air pollution from conception to late adolescence. Effects of growth-stage air pollution exposure on the gut microbiome, host metabolites, and brain tissue were assessed. Pathological damage in the hippocampus and cortex was observed. Fecal metagenomic sequencing revealed alterations in both compositions and functions of the gut microbiome. Metabolic disturbances in unsaturated fatty acids and glycerophospholipids were identified in the intestine, serum, and brain tissues, with significant changes in metabolites (e.g., gamma-linolenic acid, alpha-linolenic acid, docosahexaenoic acid (DHA), phosphatidylethanolamine (PE), phosphatidylcholine (PC) and phosphatidylserine (PS). Serum levels of the pro-inflammatory mediator leukotriene C4 were also elevated. Correlation analysis identified a group of different gut microbiome species that were associated with host metabolites. Furthermore, mediation analysis showed that intestinal and serum metabolites mediated the associations between the key gut microbiome and brain microbiome. These findings indicate that the metabolic crosstalk in the gut-brain axis mediates the neuronal damage in mice induced by growth-stage air pollution exposure, potentially through pathways involving lipid metabolism and inflammation.

Insights into high-altitude adaptation and meat quality regulation by gastrointestinal metabolites in Tibetan and black pigs

Introduction

Tibetan pigs, native to the Qinghai-Tibet Plateau, have adapted over millennia to extreme conditions such as low oxygen, harsh cold, and high UV radiation, impacting their muscle characteristics and digestive tract microbiota. The quality of pork from Tibetan pigs (TP) and black pigs (BP) is influenced by various factors, including genetics, diet, and environmental adaptation. However, the specific influence of digestive tract microbiota metabolites on muscle traits remains poorly understood. Our goal was to correlate omic variations with meat quality traits and identify potential biomarkers predictive of superior meat quality, elucidate the regulatory effects of digestive tract microbial metabolites on Tibetan pig muscle characteristics, and reveal the genetic and nutritional mechanisms that promote adaptation to extreme environmental conditions.

Methods

This analysis encompassed metabolomic profiling of the entire digestive tract-including the stomach, jejunum, cecum, colon, and rectum-as well as histological, amino acid, fatty acid composition, and transcriptomic assessments of the longissimus dorsi muscle tissues to investigate how digestive tract microbial metabolites influence muscle adaptation to high altitudes.

Results

Analyses revealed that Tibetan pig muscles contain smaller, more oxidative fibers enriched with flavor-enhancing amino acids. This was accompanied by a more favorable n-6/n-3 fatty acid ratio. Distinct patterns of microbial metabolites were observed in the digestive tract, influencing protein digestion and purine metabolism, and correlating with muscle glycine levels. Transcriptomic data showed varied gene expression in metabolic pathways related to salivary and pancreatic secretion, as well as carbohydrate and fatty acid metabolism. Integrated multi-omics approaches linked stomach metabolism, particularly through bile secretion pathways influenced by acetylcholine, to muscle functionality, highlighting the important role played by the ATP1B4 gene in enabling muscle physiology in Tibetan pigs.

Discussion

This study highlights the importance of targeted dietary interventions in improving meat quality for specific pig breeds. It also provides a theoretical foundation for precision agriculture strategies aimed at enhancing the meat quality of both TP and BP pigs.

Photoredox-Catalyzed Radical Cyclization of Unactivated Alkene-Substituted β-Ketoesters Enabled Asymmetric Total Synthesis of Tricyclic Prostaglandin D2 Metabolite Methyl Ester

Regio- and stereoselective photoredox-catalyzed cyclizations of alkene-substituted β-ketoesters have been accomplished for the synthesis of polyfunctionalized cyclopentanones. This was achieved using 2,3,5,6-tetrakis(carbazol-9-yl)-1,4-dicyanobenzene (4CzTPN) and 2,4,6-triisopropyl-thiophenol as cocatalysts under illumination of a blue-light-emitting-diode at ambient temperature. The developed chemistry was successfully applied in the enantioselective total synthesis of the tricyclic prostaglandin D2 metabolite (tricyclic-PGDM) methyl ester, which was completed in 9 steps with an overall yield of 7%.

Coupling Subunit-Specific States to Allosteric Regulation in Homodimeric Cyclooxygenase-2

The homodimeric cyclooxygenase enzymes (COX-1 and COX-2) oxygenate arachidonic acid (AA) to generate prostaglandins. COX-2 behaves as a conformational heterodimer in solution comprised of allosteric (Eallo) and catalytic (Ecat) subunits that function cooperatively. We previously utilized 19F-nuclear magnetic resonance spectroscopy (19F-NMR) to show that the cyclooxygenase active site entrances in a COX-2 homodimer construct exhibited composite tightened and relaxed states that are dependent upon the type of ligand bound. A third state, hypothesized to represent the alteration of a loop comprised of residues 120-129, was also detected in the presence of ligands that allosterically potentiate activity. We report here studies that couple the use of 19F-NMR with COX-2 heterodimer constructs to characterize states arising in the individual subunits. Glycine and proline substitutions at Ser-121 were introduced to examine how these mutations alter the 120-129 loop. In the presence of AA, the subunits exhibited asymmetry, with tightened and relaxed states observed in Eallo and Ecat, respectively. Allosteric ligand binding resulted in a shift to equivalent symmetrical states, with tightened states observed in the presence of the allosteric inhibitor flurbiprofen and relaxed states observed in the presence of the allosteric potentiator palmitic acid. The S121P substitution results in a shift to equivalent relaxed states, as well as an alteration of the 120-129 loop in the absence of bound ligand. We put forth a model linking the observed differential states arising from allosteric ligand binding with structural transitions across the dimer interface that govern the regulation of cyclooxygenase activity.

Advances in isoxazole chemistry and their role in drug discovery

Isoxazoles are a class of five-membered heterocyclic compounds that have gained significant attention in medicinal chemistry due to their diverse biological activities and therapeutic potential. Recent advances in isoxazole chemistry have led to the development of novel synthetic strategies, enabling the creation of a wide array of isoxazole derivatives with enhanced bioactivity and selectivity. This review explores the latest progress in isoxazole synthesis, highlighting key methodologies such as transition metal-catalyzed cycloadditions, green chemistry approaches, and regioselective functionalization techniques. These advances have not only improved the efficiency of isoxazole synthesis but have also facilitated the design of more complex and bioactive derivatives. In addition to their synthetic advances, isoxazoles have demonstrated a broad spectrum of biological activities, including antimicrobial, anticancer, anti-inflammatory, and neuroprotective effects, making them attractive candidates in drug discovery. This review discusses the structural modifications that enhance their pharmacological properties and their potential for developing therapies for diseases such as cancer, neurodegenerative disorders, and infections. Moreover, we examine the emerging trends in isoxazole-based drug discovery, such as the development of multi-targeted therapies and personalized medicine approaches. The evolving role of isoxazoles in drug discovery underscores their continued importance in modern pharmaceutical research and their potential to address unmet medical needs.

Deeper insights into the stability of oxylipins in human plasma across multiple freeze-thaw cycles and storage conditions

Oxylipins are signaling lipids derived from the oxidation of polyunsaturated fatty acids (PUFAs). In lipidomic studies, human plasma may be subjected to various storage conditions and freeze-thaw cycles, which may impact the analysis of these compounds. In this study, we used liquid chromatography coupled with mass spectrometry (LC-MS) to examine the influence of up to five freeze-thaw cycles (FTCs) on free and total (mostly esterified) oxylipins in human plasma and the influence of temperature and storage duration (4 °C for up to 120 h and -20 °C and -80 °C for 1-98 days) in the presence or absence of butylated hydroxytoluene (BHT) on extracted oxylipins stored in LC-MS amber vials. In fresh plasma subjected to several FTCs, approximately 48 % of the detected free oxylipins were significantly altered by the third cycle, with increases in cytochrome P450 (CYP450) and lipoxygenase (LOX)-derived compounds and reductions in trihydroxylated oxylipins. In contrast, multiple FTCs did not significantly alter esterified oxylipins. At 4 °C, the extracted oxylipins did not change significantly for up to 120 h (5 days). Oxylipin levels remained stable for 98 days at -80 °C but decreased by 98 days at -20 °C. The antioxidant activity of butylated hydroxytoluene (BHT) did not influence oxylipin stability at 4 °C for 120 h or at -80 °C for 98 days, but it reduced oxylipin degradation at -20 °C at 98 days. Conversely, prostaglandin F2α (PGF2α) exhibited substantial increases at -20 °C and -80 °C, independent of BHT. This study demonstrates that (i) unlike free oxylipins, the esterified oxylipin pool remains stable following repeated FTCs, (ii) extracted oxylipins are stable at 4 °C for up to 120 h and at -80 °C for up to 98 days, but not at -20 °C for 98 days, and (iii) BHT may minimize oxylipin degradation of sample extracts stored at -20 °C. This study provides a framework for measuring oxylipins under various freeze-thaw and storage conditions.

4-Aza Cyclopentenone Prostaglandin Analogues: Synthesis and NF-κB Inhibitory Activities

Inspired by the cyclopentenone family of prostaglandins, a series of 4-aza, cross-conjugated cyclopentenones is described. Synthesised from N-protected (4R)-aza-cyclopentenone 5, the exocyclic alkene was installed using a modified Baylis-Hillman type aldol reaction, whereby carbon-carbon bond formation is accompanied by dehydration. In this manner octanal and octenal, for example, can be introduced to mimic the ω-group present in the natural prostaglandins. Similarly, a focused range of alternative substituents were introduced using different aldehydes and ketones. The presence of the tert-butyloxycarbonyl (Boc) group on the 4-amino-cyclopentenone substituent enabled subsequent derivatisation and various electrophiles were successfully incorporated. The ability of the family of 4-amino functionalised cross-conjugated cyclopentenones to block activation of nuclear factor-kappa B (NF-κB) was studied and compared with the natural prostanoid, Δ12,14-15-deoxy-PGJ2 (2). Thereafter, the synthesis of a series of thiol adducts from these compounds were prepared and similarly evaluated biologically. The adducts showed comparable and, on occasion, more potent inhibition of NF-κB than their cyclopentenone precursors and generally demonstrated diminished cytotoxicity. For example, cross-conjugated dieneone 12 inhibited the activation of NF-κB with an IC50 value of 6.2 μM, whereas its endocyclic N-Boc (27) and N-acetyl (28) cysteine adducts blocked NF-κB activity with values of 1.0 and 8.0 μM respectively.

STForte: tissue context-specific encoding and consistency-aware spatial imputation for spatially resolved transcriptomics

Encoding spatially resolved transcriptomics (SRT) data serves to identify the biological semantics of RNA expression within the tissue while preserving spatial characteristics. Depending on the analytical scenario, one may focus on different contextual structures of tissues. For instance, anatomical regions reveal consistent patterns by focusing on spatial homogeneity, while elucidating complex tumor micro-environments requires more expression heterogeneity. However, current spatial encoding methods lack consideration of the tissue context. Meanwhile, most developed SRT technologies are still limited in providing exact patterns of intact tissues due to limitations such as low resolution or missed measurements. Here, we propose STForte, a novel pairwise graph autoencoder-based approach with cross-reconstruction and adversarial distribution matching, to model the spatial homogeneity and expression heterogeneity of SRT data. STForte extracts interpretable latent encodings, enabling downstream analysis by accurately portraying various tissue contexts. Moreover, STForte allows spatial imputation using only spatial consistency to restore the biological patterns of unobserved locations or low-quality cells, thereby providing fine-grained views to enhance the SRT analysis. Extensive evaluations of datasets under different scenarios and SRT platforms demonstrate that STForte is a scalable and versatile tool for providing enhanced insights into spatial data analysis.

In vivo and in silico anti-inflammatory activity of Artemisia vulgaris and β-caryophyllene oxide in carrageenan-induced paw edema in Wistar rats

This study is aimed to evaluate the impact of methanolic extract of Artemisia vulgaris and isolated plant compound, β-Caryophyllene oxide against carrageenan-induced paw edema in rat model and its therapeutic potential compared with reference drug, Indometacin. Methanolic extract of A. vulgaris was characterized using FTIR, LC-MS, NMR spectral studies. Paw edema was induced by sub-plantar injection of 100 µl of 1% carrageenan. Oxidative enzymes, such as super oxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR), lipid peroxidation and C-reactive protein levels were measured in paw tissue. In silico evaluation of anti-inflammatory activity of plant compounds was evaluated against the molecular targets of inflammation. C-reactive protein and lipid-peroxidation levels were significantly increased whereas the activity levels of oxidative enzymes were significantly decreased in inflammation-induced rats. The recovery of oxidative enzyme levels was seen in treated groups in a dose dependent manner. C-reactive protein and lipid-peroxidation levels were significantly decreased in treated groups, indicating the anti-inflammatory activity of the plant extract and the plant compound. Computational analysis rationalizes the inhibitory ability of plant derived compound possibly by altering the inflammatory signaling pathway.

Mechanisms of immunity in acutely decompensated cirrhosis and acute-on-chronic liver failure

The identification of systemic inflammation (SI) as a central player in the orchestration of acute-on-chronic liver failure (ACLF) has opened new avenues for the understanding of the pathophysiological mechanisms underlying this disease condition. ACLF, which develops in patients with acute decompensation of cirrhosis, is characterized by single or multiple organ failure and high risk of short-term (28-day) mortality. Its poor outcome is closely associated with the severity of the systemic inflammatory response. In this review, we describe the key features of SI in patients with acutely decompensated cirrhosis and ACLF, including the presence of a high blood white cell count and increased levels of inflammatory mediators in systemic circulation. We also discuss the main triggers (i.e. pathogen- and damage-associated molecular patterns), the cell effectors (i.e. neutrophils, monocytes and lymphocytes), the humoral mediators (acute phase proteins, cytokines, chemokines, growth factors and bioactive lipid mediators) and the factors that influence the systemic inflammatory response that drive organ failure and mortality in ACLF. The role of immunological exhaustion and/or immunoparalysis in the context of exacerbated inflammatory responses that predispose ACLF patients to secondary infections and re-escalation of end-organ dysfunction and mortality are also reviewed. Finally, several new potential immunogenic therapeutic targets are debated.

Marine Phytoplankton Bioactive Lipids and Their Perspectives in Clinical Inflammation

Marine phytoplankton is an emerging source of immunomodulatory bioactive lipids (BLs). Under physiological growth conditions and upon stress challenges, several eukaryotic microalgal species accumulate lipid metabolites that resemble the precursors of animal mediators of inflammation: eicosanoids and prostaglandins. Therefore, marine phytoplankton could serve as a biotechnological platform to produce functional BLs with therapeutic applications in the management of chronic inflammatory diseases and other clinical conditions. However, to be commercially competitive, the lipidic precursor yields should be enhanced. Beside tailoring the cultivation of native producers, genetic engineering is a feasible strategy to accrue the production of lipid metabolites and to introduce heterologous biosynthetic pathways in microalgal hosts. Here, we present the state-of-the-art clinical research on immunomodulatory lipids from eukaryotic marine phytoplankton and discuss synthetic biology approaches to boost their light-driven biosynthesis.

COX-2 Inhibitor Prediction With KNIME: A Codeless Automated Machine Learning-Based Virtual Screening Workflow

Cyclooxygenase-2 (COX-2) is an enzyme that plays a crucial role in inflammation by converting arachidonic acid into prostaglandins. The overexpression of enzyme is associated with conditions such as cancer, arthritis, and Alzheimer's disease (AD), where it contributes to neuroinflammation. In silico virtual screening is pivotal in early-stage drug discovery; however, the absence of coding or machine learning expertise can impede the development of reliable computational models capable of accurately predicting inhibitor compounds based on their chemical structure. In this study, we developed an automated KNIME workflow for predicting the COX-2 inhibitory potential of novel molecules by building a multi-level ensemble model constructed with five machine learning algorithms (i.e., Logistic Regression, K-Nearest Neighbors, Decision Tree, Random Forest, and Extreme Gradient Boosting) and various molecular and fingerprint descriptors (i.e., AtomPair, Avalon, MACCS, Morgan, RDKit, and Pattern). Post-applicability domain filtering, the final majority voting-based ensemble model achieved 90.0% balanced accuracy, 87.7% precision, and 86.4% recall on the external validation set. The freely accessible workflow empowers users to swiftly and effortlessly predict COX-2 inhibitors, eliminating the need for any prior knowledge in machine learning, coding, or statistical modeling, significantly broadening its accessibility. While beginners can seamlessly use the tool as is, experienced KNIME users can leverage it as a foundation to build advanced workflows, driving further research and innovation.

Next generation thiazolyl ketone inhibitors of cytosolic phospholipase A2 α for targeted cancer therapy

Eicosanoids are key players in inflammatory diseases and cancer. Targeting their production by inhibiting Group IVA cytosolic phospholipase A2 (cPLA2α) offers a promising approach for cancer therapy. In this study, we synthesize a second generation of thiazolyl ketone inhibitors of cPLA2α starting with compound GK470 (AVX235) and test their in vitro and cellular activities. We identify a more potent and selective lead molecule, GK420 (AVX420), which we test in parallel with AVX235 and a structurally unrelated compound, AVX002 for inhibition of cell viability across a panel of cancer cell lines. From this, we show that activity of polycomb group repressive complex 2 is a key molecular determinant of sensitivity to cPLA2α inhibition, while resistance depends on antioxidant response pathways. Consistent with these results, we show that elevated intracellular reactive oxygen species and activating transcription factor 4 target gene expression precede cell death in AVX420-sensitive T-cell acute lymphoblastic leukemia cells. Our findings imply cPLA2α may support cancer by mitigating oxidative stress and inhibiting tumor suppressor expression and suggest that AVX420 has potential for treating acute leukemias and other cancers that are susceptible to oxidative cell death.

Neutrophils in cancer: from biology to therapy

The view of neutrophils has shifted from simple phagocytic cells, whose main function is to kill pathogens, to very complex cells that are also involved in immune regulation and tissue repair. These cells are essential for maintaining and regaining tissue homeostasis. Neutrophils can be viewed as double-edged swords in a range of situations. The potent killing machinery necessary for immune responses to pathogens can easily lead to collateral damage to host tissues when inappropriately controlled. Furthermore, some subtypes of neutrophils are potent pathogen killers, whereas others are immunosuppressive or can aid in tissue healing. Finally, in tumor immunology, many examples of both protumorigenic and antitumorigenic properties of neutrophils have been described. This has important consequences for cancer therapy, as targeting neutrophils can lead to either suppressed or stimulated antitumor responses. This review will discuss the current knowledge regarding the pro- and antitumorigenic roles of neutrophils, leading to the concept of a confused state of neutrophil-driven pro-/antitumor responses.

In Silico Analysis Revealed Marco (SR-A6) and Abca1/2 as Potential Regulators of Lipid Metabolism in M1 Macrophage Hysteresis

Macrophages undergo polarization, resulting in distinct phenotypes. These transitions, including de-/repolarization, lead to hysteresis, where cells retain genetic and epigenetic signatures of previous states, influencing macrophage function. We previously identified a set of interferon-stimulated genes (ISGs) associated with high lipid levels in macrophages that exhibited hysteresis following M1 polarization, suggesting potential alterations in lipid metabolism. In this study, we applied weighted gene co-expression network analysis (WGCNA) and conducted comparative analyses on 162 RNA-seq samples from de-/repolarized and lipid-loaded macrophages, followed by functional exploration. Our results demonstrate that during M1 hysteresis, the sustained high expression of Marco (SR-A6) enhances lipid uptake, while the suppression of Abca1/2 reduces lipid efflux, collectively leading to elevated intracellular lipid levels. This accumulation may compensate for reduced cholesterol biosynthesis and provide energy for sustained inflammatory responses and interferon signaling. Our findings elucidate the relationship between M1 hysteresis and lipid metabolism, contributing to understanding the underlying mechanisms of macrophage hysteresis.

Lc-ms-based untargeted metabolomics reveals potential mechanisms of histologic chronic inflammation promoting prostate hyperplasia

BACKGROUND

Chronic prostatitis may be a risk factor for developing proliferative changes in the prostate, although the underlying mechanisms are not entirely comprehended.

MATERIALS AND METHODS

Fifty individual prostate tissues were examined in this study, consisting of 25 patients diagnosed with prostatic hyperplasia combined with histologic chronic inflammation and 25 patients diagnosed with prostatic hyperplasia alone. We employed UPLC-Q-TOF-MS-based untargeted metabolomics using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry to identify differential metabolites that can reveal the mechanisms that underlie the promotion of prostate hyperplasia by histologic chronic inflammation. Selected differential endogenous metabolites were analyzed using bioinformatics and subjected to metabolic pathway studies.

RESULTS

Nineteen differential metabolites, consisting of nine up-regulated and ten down-regulated, were identified between the two groups of patients. These groups included individuals with combined histologic chronic inflammation and those with prostatic hyperplasia alone. Glycerolipids, glycerophospholipids, and sphingolipids were primarily the components present. Metabolic pathway enrichment was conducted on the identified differentially expressed metabolites. Topological pathway analysis revealed the differential metabolites' predominant involvement in sphingolipid, ether lipid, and glycerophospholipid metabolism. The metabolites involved in sphingolipid metabolism were Sphingosine, Cer (d18:1/24:1), and Phytosphingosine. The metabolites involved in ether lipid metabolism were Glycerophosphocholine and LysoPC (O-18:0/0:0). The metabolites involved in glycerophospholipid metabolism were LysoPC (P-18:0/0:0) and Glycerophosphocholine. with Impact > 0. 1 and FDR < 0. 05, the most important metabolic pathway was sphingolipid metabolism.

CONCLUSIONS

In conclusion, our findings suggest that patients with prostate hyperplasia and combined histologic chronic inflammation possess distinctive metabolic profiles. These differential metabolites appear to play a significant role in the pathogenesis of histologic chronic inflammation-induced prostate hyperplasia, primarily through the regulation of sphingolipids and glycerophospholipids metabolic pathways. The mechanism by which histologic chronic inflammation promotes prostate hyperplasia was elucidated through the analysis of small molecule metabolites. These findings support the notion that chronic prostatitis may contribute to an increased risk of prostate hyperplasia.

Assessment of binding affinity of major bioactive compounds from Momordica charantia, Azadirachta indica, Nelumbo nucifera, Caesalpinia crista, Martynia annua and Erythrina variegate to COX-2 receptor: an in silico study

In traditional medicine, potential anti-inflammatory and pain-relieving activity of Momordica charantia, Azadirachta indica, Nelumbo nucifera, Caesalpinia crista, Martynia annua and Erythrina variegate has been emphasized. In this study, we explored binding affinity of 36 bioactive compounds from these plants to cyclooxygenase-2 (COX-2) receptor using docking method. Six compounds namely, beta carotene, lycopene, lutein, momordicoside, rutin and azadirachtin showed excellent binding affinities (-10.29, -10.22, -10.03, -7.9, -8.81 and -7.88 kcal/mol, respectively) and stable interactions with COX-2 (greater than those of aspirin and diclofenac) and they were chosen for the molecular dynamics (MD) assessments done throughout a 100-ns time period. Based on the computed RMSD, RMSF, Rg, SASA and PCA, all ligands were found to form stable and adequate interactions with COX-2 protein; these findings were comparable to those of aspirin and diclofenac, indicating the potential inhibitory properties of these ligands on COX-2 protein. In addition, the toxicity of compounds was evaluated using Pred-hERG, Pred-Skin and ProTox-II. Since COX-2 inhibitors have been reported to activate the Nrf2 pathway, it is hypothesized that they may confer other health-promoting effects through triggering Nrf2 signaling.

Structure of a model lipid membrane oxidized by human 15-lipoxygenase-2

Enzyme-mediated lipid oxidation is an important regulatory event in cell signaling, with oxidized lipids being potent signaling molecules that can illicit dramatic changes in cell behavior. For example, peroxidation of an arachidonoyl poly-unsaturated fatty acid by the human enzyme 15-lipoxygenase-2 (15-LOX-2) has been associated with formation of atherosclerotic plaques. Previous work on synthetically oxidized membranes has shown that oxidized lipid tails will change their conformation to facilitate interactions between the peroxide group and the lipid headgroups. However, this phenomenon has not been directly observed for a lipid membrane that has undergone enzyme-catalyzed oxidation. In this study, we report on the structure of a model lipid membrane before and after oxidation by 15-LOX-2. A model lipid membrane monolayer at the air-liquid interface was constructed from 1-stearoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (SAPC) in a Langmuir trough, and X-ray reflectivity measurements were conducted to determine the electron density profile of the system. Exposure to 15-LOX-2 caused a dramatic change in the SAPC structure, namely a blurred distinction between the lipid tail/head layers and shortening of the average lipid tail length by ∼3 Å. The electron density profile of the oxidized SAPC monolayer is similar to that of a synthetically oxidized substrate mimic. Overall, this reported observation of an enzymatically-oxidized membrane structure in situ is helping to bridge a gap in the literature between structural studies on synthetically oxidized membranes and cellular studies aiming to understand physiological responses.

Metformin protects against small intestine damage induced by diabetes and dunning's prostate cancer: A biochemical and histological study

The oral biguanide metformin is used to treat type 2 diabetic mellitus (T2DM). Anti-cancer effects have been proven by metformin in different hormone-sensitive tumors, including breast, pancreatic, colon, and prostate cancer. Therefore, we investigated whether metformin could defend against small intestine damage in Dunning's prostate cancer. The study divided the six groups of male Copenhagen rats into the following categories: control, diabetic (D), cancer (C), diabetic + cancer (DC), cancer + metformin (CM), and diabetic + cancer + metformin (DCM). After sacrifice, the small intestines were removed to assess biochemical markers and histopathological evaluation. Biochemical evaluations showed that glutathione (reduced) levels and other enzyme activities related antioxidant systems, paraoxonase, sodium potassium ATPase, acetylcholinesterase activities were decreased. In contrast, lipid peroxidation, total oxidant status, reactive oxygen species, interleukin-1β, interleukin-6, tumor necrosis factor-α, sucrase, maltase, trypsin, myeloperoxidase, xanthine oxidase activities, protein carbonyl contents and sialic acid levels were raised in the damaged groups. Treatment with metformin restored all of this. The histological assessment revealed moderate to severe damage in the small intestine following processes D and C. According to the study's findings, metformin treatment led to a notable decline in histopathological damage in the C and DC. A slight lowering in inflammatory cells and an improvement in the damaged gland integrity in the small intestine were noted with metformin treatment.​ Metformin use protected the small intestinal tissue damage and decreased oxidative stress.

Lactobacillus fermentum MCC2760 Attenuates Heated Oil-Induced Brain Oxidative Stress and Inflammation via Modulation of NRF2 and NF-kB in Rats

SCOPE

Reusing deep-fried oil is a common practice to cut costs, and their consumption may affect brain function. Hence, the study investigates the modulatory potential of Lactobacillus fermentum MCC2760 (LF) on heated oil-induced brain oxidative stress (OS) and inflammation that may have a bearing on cognition in experimental rats.

METHODS AND RESULTS

Female Wistar rats are fed with diets containing native sunflower oil (N-SFO), native canola oil (N-CNO), heated sunflower oil (H-SFO), heated canola oil (H-CNO), heated sunflower oil with probiotic (H-SFO + LF), or heated canola oil with probiotic (H-CNO + LF} for 60 days. Compared to respective controls, heated oils significantly (p < 0.05) increased OS by decreasing antioxidant defense enzymes and nuclear factor erythroid 2-related factor 2 (NRF2) activity. Further, heated oil elevates brain expression of cytosolic phospholipase A2 (cPLA2), cyclooxygenase-2 (COX-2), prostaglandin-E receptor 4 (EP-4), intercellular adhesion molecule 1 (ICAM-1), nitric oxide synthase 2 (NOS-2), followed by an increased production of proinflammatory eicosanoids (prostaglandin E2 [PGE2] and leukotriene B4 [LTB4]) and cytokines (tumor necrosis factor-α [TNF-α], monocyte chemoattractant protein-1 [MCP-1], interleukin-1β [IL-1β], and interleukin-6 [IL-6]). The increased nuclear translocation of nuclear factor kappa beta (NF-kB) in heated oil-fed groups' brains corroborates the heightened inflammatory response. Heated oils decrease neurotrophins and neuron development markers. However, administration of LF abrogates the heated oil-induced alterations significantly (p < 0.05).

CONCLUSIONS

The present study is novel in demonstrating the protective role of probiotic LF against heated-oil-induced brain OS and inflammation in rats.

Postmortem Fatty Acid Abnormalities in the Cerebellum of Patients with Essential Tremor

Fatty acids play many critical roles in brain function but have not been investigated in essential tremor (ET), a frequent movement disorder suspected to involve cerebellar dysfunction. Here, we report a postmortem comparative analysis of fatty acid profiles by gas chromatography in the cerebellar cortex from ET patients (n = 15), Parkinson's disease (PD) patients (n = 15) and Controls (n = 17). Phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylinositol (PI)/ phosphatidylserine (PS) were separated by thin-layer chromatography and analyzed separately. First, the total amounts of fatty acids retrieved from the cerebellar cortex were lower in ET patients compared with PD patients, including monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA). The diagnosis of ET was associated with lower cerebellar levels of saturated fatty acids (SFA) and PUFA (DHA and ARA) in the PE fraction specifically, but with a higher relative content of dihomo-γ-linolenic acid (DGLA; 20:3 ω-6) in the PC fraction. In contrast, a diagnosis of PD was associated with higher absolute concentrations of SFA, MUFA and ω-6 PUFA in the PI + PS fractions. However, relative PI + PS contents of ω-6 PUFA were lower in both PD and ET patients. Finally, linear regression analyses showed that the ω-3:ω-6 PUFA ratio was positively associated with age of death, but inversely associated with insoluble α-synuclein. Although it remains unclear how these FA changes in the cerebellum are implicated in ET or PD pathophysiology, they may be related to an ongoing neurodegenerative process or to dietary intake differences. The present findings provide a window of opportunity for lipid-based therapeutic nutritional intervention.

U-73122, a phospholipase C inhibitor, impairs lymphocytic choriomeningitis virus virion infectivity

Lassa virus (LASV) is an Old World (OW) mammarenavirus that causes Lassa fever, a life-threatening acute febrile disease endemic in West Africa. Lymphocytic choriomeningitis virus (LCMV) is a worldwide-distributed, prototypic OW mammarenavirus of clinical significance that has been largely neglected as a human pathogen. No licensed OW mammarenavirus vaccines are available, and the current therapeutic option is limited to the off-label use of ribavirin, which offers only partial efficacy. This situation underscores the urgent need to develop novel antivirals against human pathogenic mammarenaviruses. Previously, we showed that afatinib, a pan-ErbB tyrosine kinase inhibitor, inhibited multiple steps of the life cycles of OW LASV and LCMV, as well as the New World Junín virus vaccine strain Candid#1. In the present study, we investigated the inhibitory effect of U-73122, a phospholipase C inhibitor that acts downstream of ErbB signalling, on LCMV multiplication. U-73122 inhibited WT recombinant (r) LCMV multiplication in cultured cells. Preincubation of cell-free LCMV virions with U-73122 resulted in impaired virion infectivity. U-73122 also inhibited the infection of rLCMVs expressing heterologous viral glycoproteins, including the vesicular stomatitis Indiana virus (VSIV) glycoprotein, whereas WT VSIV infection was not affected by U-73122 treatment. Our results show the novel bioactivity of U-73122 as an LCMV inhibitor and indicate the presence of a virion-associated molecule that is necessary for virion infectivity and can be exploited as a potential antiviral drug target against human pathogenic mammarenavirus infections.

Comprehensive Analysis of the Tumour Immune Microenvironment in Canine Urothelial Carcinoma Reveals Immunosuppressive Mechanisms Induced by the COX-Prostanoid Cascade

A comprehensive understanding of the tumour immune microenvironment (TIME) is essential for advancing precision medicine and identifying potential therapeutic targets. This study focused on canine urothelial carcinoma (cUC) recognised for its high sensitivity to cyclooxygenase (COX) inhibitors. Using immunohistochemical techniques, we quantified the infiltration of seven immune cell populations within cUC tumour tissue to identify clinicopathological features that characterise the TIME in cUC. Our results revealed several notable factors, including the significantly higher levels of CD3+ T cells and CD8+ T cells within tumour cell nests in cases treated with preoperative COX inhibitors compared to untreated cases. Based on the immunohistochemistry data, we further performed a comparative analysis using publicly available RNA-seq data from untreated cUC tissues (n = 29) and normal bladder tissues (n = 4) to explore the link between COX-prostanoid pathways and the immune response to tumours. We observed increased expression of COX-2, microsomal prostaglandin E2 synthase-1 (mPGES-1) and mPGES-2 in cUC tissues. However, only mPGES-2 showed a negative correlation with the cytotoxic T-cell (CTL)-related genes CD8A and granzyme B (GZMB). In addition, a broader analysis of solid tumours using The Cancer Genome Atlas (TCGA) database revealed similar patterns in several human tumours, suggesting a common mechanism in dogs and humans. Our results suggest that the COX-2/mPGES-2 pathway may act as a cross-species tumour-intrinsic factor that weakens anti-tumour immunity, and that COX inhibitors may convert TIME from a 'cold tumour' to a 'hot tumour' state by counteracting COX/mPGES-2-mediated immunosuppression.

Deeply Saddening Life Events Play a Carcinogenic Role by Inducing Mutations in ALOX12 and FKBP5 Genes

BACKGROUND/OBJECTIVES

In the past few decades, many studies have been conducted to find out that psychological stress and cancer are closely linked. Moreover, it was reported that stress can induce mutations in gene level. Therefore, in this study we want to examine a relationship between stressful life events, gene mutation and cancer.

METHODS

Stressful Life Experiences Screening (SLES), Hospital Anxiety and Depression Scale (HADS) and the Coping with Stress Style Scale (CSS) were applied to the participants to examine relationship between stress and cancer.

RESULTS

NGS results showed higher level of mutations accumulated on FKBP5 and ALOX12 genes in cancer patients who were exposed to stressful life events. The expression status of ALOX12 and FKBP5 genes on patients with or without cancer and several cancer cell lines demonstrated that both ALOX12 and FKBP5 mRNA levels were downregulated only in cancer patients and cancer cell lines but not in cancer free control groups. Re-created overexpression of the WT-ALOX12 and WT-FKBP5 extremely inhibited cellular growth, cellular invasion in cancer cell lines, tumor growth in xenograft model too.

CONCLUSIONS

Our results indicate that Stressful Life Experiences may induce cancer development by increased somatic mutations in ALOX12 and FKBP5 genes.

The Cardioprotective Effects of Polyunsaturated Fatty Acids Depends on the Balance Between Their Anti- and Pro-Oxidative Properties

Polyunsaturated fatty acids (PUFAs) are not only structural components of membrane phospholipids and energy storage molecules in cells. PUFAs are important factors that regulate various biological functions, including inflammation, oxidation, and immunity. Both n-3 and n-6 PUFAs from cell membranes can be metabolized into pro-inflammatory and anti-inflammatory metabolites that, in turn, influence cardiovascular health in humans. The role that PUFAs play in organisms depends primarily on their structure, quantity, and the availability of enzymes responsible for their metabolism. n-3 PUFAs, such as eicosapentaenoic (EPA) and docosahexaenoic (DHA), are generally known for anti-inflammatory and atheroprotective properties. On the other hand, n-6 FAs, such as arachidonic acid (AA), are precursors of lipid mediators that display mostly pro-inflammatory properties and may attenuate the efficacy of n-3 by competition for the same enzymes. However, a completely different light on the role of PUFAs was shed due to studies on the influence of PUFAs on new-onset atrial fibrillation. This review analyzes the role of PUFAs and PUFA derivatives in health-related effects, considering both confirmed benefits and newly arising controversies.

Evaluation of the Optimum Dietary Arachidonic Acid Level and Its Essentiality for Black Seabream (Acanthopagrus schlegelii): Based on Growth and Lipid Metabolism

The aim of this study was to investigate how dietary arachidonic acid (ARA) level affects growth performance and lipid metabolism in juvenile black seabream (Acanthopagrus schlegelii). A feeding trial was conducted for 8 weeks, during which the fish (0.99 ± 0.10 g) were fed six isonitrogenous and isolipidic diets with varying ARA levels of 0.1%, 0.59%, 1.04%, 1.42%, 1.94%, and 2.42%. Fish fed the diet with 1.42% ARA had significantly higher weight gain (WG) and specific growth rate (SGR) than the other groups (p < 0.05), except for the ARA1.04. As the ARA level increased, the liver and muscle effectively accumulated n-6 polyunsaturated fatty acids (n-6 PUFAs; p < 0.05). However, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and n-3 PUFA contents of liver and muscle significantly decreased by increasing dietary ARA level (p < 0.05). Results of liver histology showed dramatically increased vacuolar fat droplets leading to hepatic fat pathological changes in fish fed diets with ARA levels of 1.94% and 2.42% (p < 0.05). Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities increased with increasing dietary ARA level which was accompanied with elevated liver lipid content (p < 0.05). Consistently, triglyceride (TG) and nonesterified fatty acid (NEFA) concentrations of serum and liver, and serum cholesterol (CHO) concentration increased (p < 0.05). As the level of dietary ARA increased, the indicators of lipid metabolism such as sirtuin 1 (sirt1) and peroxisome proliferator-activated receptor α (pparα) also increased (p < 0.05). However, after reaching their peak in ARA1.04 group, the level of these indicators declined (p < 0.05). The same trend was observed for the expression of genes related to the downstream pathways. While the mRNA levels of sterol regulatory element-binding protein-1 (srebp-1) and its downstream genes were markedly increased with the increase of dietary ARA level (p < 0.05). In conclusion, these data suggested that the optimum dietary ARA requirement of A. schlegelii is 1.03% of diet based on the WG. The study revealed that a diet containing 1.04% ARA can activate the expression levels of sirt1 and pparα leading to promoted lipolysis. However, dietary ARA levels of ≥1.42% induced lipid accumulation in the liver, as they suppressed the mRNA levels of sirt1 and pparα, while elevating the expression level of genes related to lipogenesis.

Bacteriocin Microcin J25's antibacterial infection effects and novel non-microbial regulatory mechanisms: differential regulation of dopaminergic receptors

BACKGROUND

The antibacterial and immunomodulatory activities of bacteriocins make them attractive targets for development as anti-infective drugs. Although the importance of the enteric nervous system (ENS) in the struggle against infections of the intestine has been demonstrated, whether it is involved in bacteriocins anti-infective mechanisms is poorly defined.

RESULTS

Here, we demonstrated that the bacteriocin Microcin J25 (J25) significantly alleviated diarrhea and intestinal inflammation in piglets caused by enterotoxigenic Escherichia coli (ETEC) infection. Mechanistically, macrophage levels were significantly downregulated after J25 treatment, and this was replicated in a mouse model. Omics analysis and validation screening revealed that J25 treatment induced significant changes in the dopaminergic neuron pathway, but little change in microbial structure. The alleviation of inflammation may occur by down-regulating dopamine receptor (DR) D1 and the downstream DAG-PKC pathway, thus inhibiting arachidonic acid decomposition, and the inhibition of macrophages may occur through the up-regulation of DRD5 and the downstream cAMP-PKA pathway, thus inhibiting NF-κB.

CONCLUSIONS

Our studies' findings provide insight into the changes and possible roles of the ENS in J25 treatment of ETEC infection, providing a more sophisticated foundational understanding for developing the application potential of J25.

Structural and Functional Biology of Mammalian ALOX Isoforms with Particular Emphasis on Enzyme Dimerization and Their Allosteric Properties

The human genome involves six functional arachidonic acid (AA) lipoxygenase (ALOX) genes, and the corresponding enzymes (ALOX15, ALOX15B, ALOX12, ALOX12B, ALOXE3, ALOX5) have been implicated in cell differentiations and in the pathogenesis of inflammatory, hyperproliferative, metabolic, and neurological disorders. Humans express two different AA 15-lipoxygenating ALOX isoforms, and these enzymes are called ALOX15 (15-LOX1) and ALOX15B (15-LOX2). Chromosomal localization, sequence alignments, and comparison of the enzyme properties suggest that pig and mouse ALOX15 orthologs (leukocyte-type 12-LOX) on the one hand and rabbit and human ALOX15 orthologs on the other (reticulocyte-type 15-LOX1) belong to the same enzyme family despite their different reaction specificities with AA as a substrate. In contrast, human ALOX12 (platelet-type 12-LOX), as well as pig and mouse ALOX15 (leukocyte-type 12-LOX), belong to different enzyme families, although they exhibit a similar reaction specificity with AA as a substrate. The complex multiplicity of mammalian ALOX isoforms and the controversial enzyme nomenclatures are highly confusing and prompted us to summarize the current knowledge on the biological functions, enzymatic properties, and allosteric regulation mechanisms of mammalian ALOX15, ALOX15B, and ALOX12 orthologs that belong to three different enzyme sub-families.

Long chain polyunsaturated fatty acid (LC-PUFA) composition of fish sperm: nexus of dietary, evolutionary, and biomechanical drivers

Long-chain polyunsaturated fatty acids (LC-PUFA) like arachidonic acid (ARA, 20:4n-6), eicosapentaenoic acid (EPA, 20:5n-3), and docosahexaenoic acid (DHA, 22:6n-3) constitute one-third to half of fish sperm lipids. Fish sperm is rich in phospholipid (PL)-primarily phosphatidylcholine, phosphatidylethanolamine, and sphingomyelin. DHA is generally the most abundant LC-PUFA in each PL class, followed by competition between ARA and EPA. While the total n-6: n-3 PUFA ratio does not correlate significantly with sperm biomechanics, LC-PUFA do. DHA positively influences sperm biomechanics, while ARA and EPA may be negatively associated. Fish sperm maintains lower (≤1) total n-6 PUFA per unit of n-3 PUFA but keep a higher (>1) ARA per unit EPA. A weak dietary influence on sperm EPA and DHA exists but not on ARA. The DHA: EPA ratio in fish sperm is often >1, though values <1 occur. Certain species cannot fortify DHA sufficiently during spermatogenesis, diverging through whole genome duplications. Fish sperm can show ARA: EPA ratios greater or less than 1, due to shifts in prostaglandin pathways in different evolutionary eras. DHA-rich PL bilayers provide unique packing and fusogenic properties, with ARA/EPA-derived eicosanoids guiding sperm rheotaxis/chemotaxis, modulated by DHA-derived resolvins. Docosapentaenoic acid (DPA, 22:5n-3) sometimes substitutes for DHA in fish sperm.

MMP-9 as a clinical marker for endometriosis: a meta-analysis and bioinformatics analysis

Aim

This study systematically evaluated the potential efficacy of serum matrix metalloproteinase-9 (MMP-9) concentration as a diagnostic marker for endometriosis through meta-analysis. Early and accurate diagnosis of endometriosis, a common gynecological disease, is crucial for improving patient prognosis. Hence, this study aimed to comprehensively analyze the data from multiple studies to assess the diagnostic value of serum MMP-9 concentration for endometriosis.

Methods

Articles investigating the association between MMP-9 and endometriosis, published from the inception of the databases until February 2024, were systematically retrieved from multiple databases, including PubMed, Embase, Cochrane, Web of Science, Scopus, and CNKI. Download and analyze the GSE7305, GSE23339, and GSE51981 datasets. Statistical analyses of all eligible studies were conducted using RevMan 5.4, Stata 11.0, and R software version 4.3.3.

Results

Fifteen studies fully met the inclusion criteria for the meta-analysis. The concentration of MMP-9 in the blood of patients with endometriosis was significantly higher compared to that of the control group (p < 0.0001). Subgroup analysis based on different stages of endometriosis revealed a trend towards significantly higher serum MMP-9 concentrations in patients, whether in stages I-II or III-IV. Bioinformatics analysis revealed differences in the expression of MMP-9 in endometrial tissue between EMT patients and healthy controls in the GSE7305 and GSE23339 datasets. Additionally, in the GSE51981 dataset, we found significant differences between the normal group and both mild and severe cases of endometriosis.

Conclusion

Both the current meta-analysis and bioinformatics analysis indicate differences in MMP-9 concentration levels between endometriosis patients and healthy individuals, with potentially elevated MMP-9 concentrations in serum samples from patients with endometriosis.

Systematic review registration

https://www.crd.york.ac.uk/prospero, identifier CRD42024525864.

Association between omega-6 fatty acid intake and asthma in US children and adolescents

BACKGROUND

Asthma is an inflammatory disease. The potential of omega-6 fatty acids to alleviate asthma symptoms through their anti-inflammatory and immunomodulatory effects has been investigated. However, the association of dietary omega-6 fatty acids in childhood and adolescent asthma remains controversial.

OBJECTIVE

The aim of this study was to evaluate the association between dietary intake of omega-6 fatty acids and asthma in children and adolescents in the United States.

METHODS

We conducted a cross-sectional analysis of 5045 children and adolescents from the National Health and Nutrition Examination Survey (NHANES) between 2013 and 2020. Covariates were adjusted, and multivariate logistic regression, restricted cubic splines, threshold effects, and subgroup analyses were used.

RESULTS

Of the 5045 participants, 1000 (19.8%) were identified as having asthma. After adjustment for potential confounders, individuals in the second group (T2, 215.3-377.7 mg/kg/day) had an adjusted odds ratio (OR) of 0.70 (95% CI: 0.57-0.86, P = 0.001) for asthma compared with those in the lowest omega-6 fatty acid intake group (T1, < 215.3 mg/kg/day). Similarly, individuals in the third group (T3, > 377.7 mg/kg/day) had an adjusted OR of 0.59 (95% CI: 0.45-0.78, P < 0.001) for asthma. Furthermore, a non-linear (L-shaped) relationship between omega-6 intake and asthma was observed (P = 0.001), with subgroup analyses confirming the stability of the results. In the threshold analysis, a critical turning point was observed at around 384.2 mg/kg/day (OR = 0.996, 95% CI: 0.995-0.998, P < 0.001).

CONCLUSION

The consumption of omega-6 fatty acids in the diet showed an L-shaped association with asthma among children and adolescents in the United States. A critical turning point was noted at approximately 384.2 mg/kg/day.

Inhibitory Effect of (2S)-Pinocembrin From Goniothalamus macrophyllus on the Prostaglandin E2 Production in Macrophage Cell Lines: In Vitro and In Silico Studies

Pinocembrin (PCB), a flavonoid known for its anti-inflammatory properties, has been approved for various clinical trial applications. To evaluate deeper into the anti-inflammatory potential of the specific enantiomer of natural PCB, we conducted the first investigation into the efficacy of the pure enantiomer (2S)-PCB in modulating inflammatory mediators induced by lipopolysaccharide (LPS) in both murine RAW 264.7 and human U937 macrophage cell lines. This particular compound was isolated from Goniothalamus macrophyllus (Annonaceae), a native plant of Indonesia. This plant has been used traditionally as an herbal medicine to alleviate inflammation. (2S)-PCB was isolated from the stem bark of G. macrophyllus by defatting with n-hexane followed by maceration with methanol. Purification was performed using several chromatographic techniques. The absolute configuration was determined using electronic circular dichroism (ECD) spectroscopy. This compound was then tested for its inhibitory activity on prostaglandin E2 (PGE2) and subjected to docking simulations. The results indicated that (2S)-PCB significantly suppressed the production of PGE2 induced by LPS in both RAW 264.7 and U937 cell lines. The docking simulations revealed that (2S)-PCB reduced PGE2 levels by suppressing mitogen-activated protein kinase (MAPK) activation through inhibiting p38 and extracellular signal-regulated kinases (ERK). These findings suggest that the compound may prevent worsening of septic shock caused by bacterial infection.