A rapid method of total lipid extraction and purification

Enhanced lipidomics workflows for plasma and extracellular vesicles through advanced liquid chromatography-tandem mass spectrometry integrated

Lipidomics, a subfield of metabolomics, provides comprehensive analysis of lipids in biological systems and is essential for biomedical research, driven by advances in analytical technologies. Lipids are crucial biomolecules in cellular functions and have been increasingly recognized for their role in physiological and pathological processes. This study focuses on advanced strategies for the development, validation, and implementation of untargeted lipidomics methods in human plasma and extracellular vesicles (EVs) using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Method validation demonstrated excellent accuracy (precision and trueness) (81-120 % of nominal value), precision with inter-day repeatability below 20 %, limits of quantification ranging from 0.25 to 25 μM, and recovery rates exceeding 80 % for most lipid classes, as well as matrix effects. Plasma samples were used as a proof-of-concept study, and the method was ultimately applied to human macrophage-derived EVs. Lipid extraction utilized four liquid-liquid extraction methods to ensure broad lipid class coverage, high recovery, and repeatability. Additionally, we demonstrated that a sonication-assisted homogenization step effectively facilitates lipid extraction from EVs. Through untargeted lipidomics, our study identifies and quantifies a diverse range of lipid species in human plasma (225 lipids analytes) and macrophage-derived EVs (124 lipids analytes) within different classes. Overall, we present sophisticated approaches that combine pre-analytical lipid extraction techniques with high-resolution LC-MS/MS to enhance lipidomics research. This approach enhances the characterization of lipid profiles and their biological implications, paving the way for applications in personalized medicine and the discovery of novel lipid biomarkers associated with EVs biogenesis.

Elucidating the toxicity of methyl parathion, imazapic, isoxaflutole, and chlorantraniliprole on human hepatocarcinoma cells and bioinspired membranes

Pesticides have boosted agricultural productivity but pose significant risks to environmental and human health. The intensification of agriculture has driven widespread pesticide use, with 66 % of global consumption allocated to sugarcane, soybean and corn. Sugarcane, a major monoculture in Brazil, India, and China, has driven a 700 % increase in pesticide use in Brazil over the past 40 years. Commonly used pesticides in Brazilian sugarcane farming include methyl parathion (PM), imazapic (IM), isoxaflutole (IS), and chlorantraniliprole (CL). Despite regulatory efforts by governmental agencies worldwide, the long-term toxicity of these substances on human health remains insufficiently studied. This study evaluates the cytotoxicity of PM, IM, IS, and CL at concentrations regulated by governmental agencies in human hepatocarcinoma (HepG2) cells. Given the liver's role in metabolizing xenobiotics, it is especially vulnerable to pesticide-toxicity. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and LDH (lactate dehydrogenase release) assays, alongside confocal microscopy, showed reduced cell viability and impaired membrane integrity, with progressive toxicity (from 24 to 96 h), primarily impacting mitochondrial activity. Surface pressure-area (π-A) isotherms, compressibility (CS⁻¹), and atomic force microscopy (AFM) revealed distinct pesticide incorporation mechanisms into Langmuir monolayers of HepG2 lipid extracts, used as membrane models. The findings underscore the hepatotoxicity of PM, IM, IS, and CL, even at concentrations regulated by governmental agencies, emphasizing their potential human health hazards.

Identification of novel oxidized phospholipids that activate platelet-activating factor receptor using HPLC fractionation and comprehensive LC-MS/MS analysis

Platelet-activating factor receptor (PAFR) is involved in various physiological processes, including the immune system and inflammatory responses. In addition to PAF, several oxidized phospholipids have been shown to act as ligands for PAFR. We have previously developed a comprehensive analysis method for oxidized phospholipids, and in this study, we employed this method to test whether additional oxidized phospholipids can activate PAFR. From an oxidized phosphatidylcholine mixture, we identified that 1-palmitoyl-2-(4'-oxo-butanoyl)-sn-glycero-3-phosphocholine (POBPC) functions as a novel PAFR activator, using preparative HPLC and comprehensive LC-MS/MS analysis of fractionated oxidized phospholipids. Next, multiple assays confirmed that POBPC acts as a bona fide PAFR agonist. The H248W mutation of PAFR attenuated the response to POBPC. Finally, POBPC induced phosphorylation of extracellular signal-regulated kinase in mouse peritoneal macrophages, which endogenously express PAFR. Our findings provide valuable insight into the biological functions of oxidized phospholipids, advancing our understanding of their roles in cellular processes.

Docosapentaenoic (22:5 n-6) and docosahexaenoic (22:6 n-3) acids exhibit highly lipogenic properties in rainbow trout preadipocytes

Dietary polyunsaturated fatty acids are essential for fish health. Adipose tissue is the major tissue for fatty acid storage in rainbow trout (Oncorhynchus mykiss), and its development and function can be impacted by the fatty acids themselves. In the present study, the effects of seven fatty acids, oleic (OA, 18:1 n-9), α-linolenic (ALA, 18:3 n-3), eicosapentaenoic (EPA, 20:5 n-3), docosahexaenoic (DHA, 22:6 n-3), linoleic (LA, 18:2 n-6), arachidonic (AA, 20:4 n-6), and docosapentaenoic (DPA, 22:5 n-6) acids, on adipogenesis were investigated in primary cultures of rainbow trout preadipocytes. In terms of lipid accumulation, DPA and DHA appeared to be the most lipogenic fatty acids, while all treatments modified the fatty acid composition of the cellular phospholipids and neutral lipids. The fatty acid of interest added to the culture medium was the most abundant in preadipocytes, while the first bioconversion products were detected in lower amounts. In terms of transcriptional effects, DPA increased the expression of the early transcription factor CCAAT/enhancer binding protein δ, while DHA upregulated the expression of genes involved in neutral lipid synthesis, notably lipoprotein lipase, fatty acid transport protein 1 and glycerol-3-phosphate dehydrogenase. Both fatty acids decreased the expression of fatty acid synthase. These results highlight that DPA and DHA exert a significant effect on lipid deposition in rainbow trout preadipocytes, potentially through different pathways, and confirm that fatty acids have major impacts on preadipocyte lipid metabolism and adipogenesis.

Effect of extraction solvents on the lipid profiles and volatile compounds of fish roe phospholipids

This study aimed to elucidate the effect of extraction solvents on the lipid profiles and volatile compounds in large yellow croaker roe phospholipids (LYPLs) with chloroform/methanol (CM), ethanol/ethanol (EE), and ethanol/hexane (EH). The results demonstrated that CM-extracted LYPLs exhibited the lowest oxidation levels, while EE-extracted LYPLs contained the highest polyunsaturated fatty acids (PUFAs) content. EH extraction was more effective for monounsaturated fatty acids (MUFAs) in LYPLs but was less effective for polar lipids. Across solvents, 410 lipids were identified, with phosphatidylcholine (PC) predominating in all LYPLs groups. The study detected 97 volatiles, with CM-extracted LYPLs showing notably high in pyrazines and benzenes. A total of 65 lipids and 47 volatiles distinguished the three LYPLs groups. Correlation analysis revealed a synergistic effect between PUFAs and lysophosphatidylcholine (LPC), increasing the production of volatile compounds associated with oxidation. These results offered new insights for optimizing future solvent extraction of marine phospholipids.

Lipidomics and cardiovascular disease

Cardiovascular diseases (CVDs) remain the leading cause of mortality worldwide, necessitating innovative approaches for early detection and personalized interventions. Lipidomics, leveraging advanced mass spectrometry techniques, has become instrumental in deciphering lipid-mediated mechanisms in CVDs. This review explores the application of lipidomics in identifying biomarkers for myocardial infarction, heart failure, stroke, and calcific aortic valve stenosis (CAVS). This review examines the technological advancements in shotgun lipidomics and LC/MS, which provide unparalleled insights into lipid composition and function. Key lipid biomarkers, including ceramides and lysophospholipids, have been linked to disease progression and therapeutic outcomes. Integrating lipidomics with genomic and proteomic data reveals the molecular underpinnings of CVDs, enhancing risk prediction and intervention strategies. This review positions lipidomics as a transformative tool in reshaping cardiovascular research and clinical practice.

Medium chain fatty acid production from CO2 in integrated dark fermentation-microbial electrosynthesis reactor

Emerging technologies aim to convert CO2 into biofuels and chemicals, reducing greenhouse gas emissions. Microbial electrosynthesis (MES) offers promise for producing organic products, but challenges remain in energy efficiency and medium-chain fatty acid (MCFA) synthesis. This study demonstrates long-term, continuous caproic acid production in an integrated dark fermentation-MES (DF-MES) system using enriched mixed cultures. A maximum caproic acid production rate of 0.47 ± 0.16 g L-1 d-1 was achieved, with a 73 % selectivity, 83 % carbon recovery and 94 % electron recovery. Integration of DF reduced external energy demand by 60 %, while continuous operation increased production rates by 14.6 % over batch mode, maintained stability for over three months. These findings highlight DF-MES integration as a viable approach to reducing energy demand while ensuring sustained caproic acid production.

TamL is a Key Player of the Outer Membrane Homeostasis in Bacteroidota

In Proteobacteria, the outer membrane protein TamA and the inner membrane-anchored protein TamB form the Translocation and Assembly Module (TAM) complex, which facilitates the transport of autotransporters, virulence factors, and likely lipids across the two membranes. In Bacteroidota, TamA is replaced by TamL, a TamA-like lipoprotein with a lipid modification at its N-terminus that likely anchors it to the outer membrane. This structural difference suggests that TamL may have a distinct function compared to TamA. However, the role of TAM in bacterial phyla other than Proteobacteria remains unexplored. Our study aimed to elucidate the function of TamL in Flavobacterium johnsoniae, an environmental Bacteroidota. Unlike its homologs in Proteobacteria, we found that TamL and TamB are essential in F. johnsoniae. Through genetic, phenotypic, proteomic, and lipidomic analyses, we show that TamL depletion severely compromises outer membrane integrity, as evidenced by reduced cell viability, altered cell shape, increased susceptibility to membrane-disrupting agents, and elevated levels of outer membrane lipoproteins. Notably, we did not observe an overall decrease in the levels of β-barrel outer membrane proteins, nor substantial alterations in outer membrane lipid composition. By pull-down assays, we found TamL co-purifying with TamB in F. johnsoniae, suggesting an interaction. Furthermore, we found that while TamL and TamB monocistronic genes are conserved among Bacteroidota, only some species encode multiple TamL, TamB and TamA proteins. To our knowledge, this study is the first to provide functional insights into a TAM subunit beyond Proteobacteria.

Edible plant oils with high n-3/n-6 polyunsaturated fatty acids ratio prolong the lifespan of Drosophila by modulating lipid metabolism

Edible plant oils with a high n-3/n-6 polyunsaturated fatty acids (PUFAs) ratio exhibit numerous health benefits, potentially due to their ability to modulate cellular lipidomes metabolism within the organism. To test this hypothesis, lifespan studies in Drosophila were conducted to assess the impact of 7 representative plant oils with different n-3/n-6 PUFA ratios on health outcomes. Subsequently, multi-dimensional MS-based shotgun lipidomics was utilized for class-targeted lipid analysis of cellular lipidomes in fly bodies. The plant oils with high n-3/n-6 PUFAs ratio significantly extended the lifespan of Drosophila, enhancing overall health. Lipidomics analysis revealed that these oils substantially increased the composition of 18:3 free FA, reduced compositions of phospholipid species containing 18:2 FA in flies, and enhanced mitochondrial functions by elevating T18:2 cardiolipin composition. The study provides insights into the mechanism(s) underlying the positive health effects of plant oils with high n-3/n-6 PUFAs ratio.

Dietary fennel (Foeniculum vulgare Mill) seeds supplementation affects yield, fatty acid composition and flavour profile of milk and cheese in grazing goats

Fennel (Foeniculum vulgare Mill) is an annual plant belonging to the family of Apiaceae, widely used in Mediterranean areas for its aromatic and medical properties, especially for carminative, digestive and galactagogue effects. In this trial, 20 multiparous goats homogeneous for body weight (BW: 50.0 ± 2 kg), parity (3rd) and milk yield (1940 ± 120 g/head/day), were randomly allocated into two groups (C: control; F: fennel) fed on a permanent pasture (9:00 am to 4:00 pm). In the pen both groups received 400 g of concentrate mixture (barley and corn meals) and group F diet was supplemented with 15 g/head/day of organic fennel seeds. From the beginning of May until September, milk yield was measured daily, and samples of milk and pasture were collected monthly and analysed, along with concentrate, for their chemical composition and fatty acid profile. Cheese samples were obtained at the beginning and at the end of the trial and analysed for chemical composition, fatty acid and VOCs profile. Milk yield was significantly higher in group F (1809.6 g vs 1418.3 g for group F and C respectively), whereas the solid content did not differ between groups. Milk fatty acid profile differed between groups, especially for the content of MUFA, PUFA, and SFA. Cheese production and composition also was different for yield, fatty acid profile and VOCs composition between the groups. Indeed, the cheese of group F had higher antioxidant capacity and 4 aromatic compounds which were completely absent in the cheese of group C. These results confirm the galactagogue activity of fennel seeds in dairy goats and suggest their potential role as feed additive in grazing system to enhance production in terms of yield and antioxidant activity.

Reversible tuning of membrane sterol levels by cyclodextrin in a dialysis setting

Large unilamellar vesicles are popular membrane models for studying the impact of lipids and bilayer properties on the structure and function of transmembrane proteins. However, the functional reconstitution of transmembrane proteins in liposomes can be challenging, especially if the hydrophobic thickness of the protein does not match the thickness of the lipid bilayer. Such hydrophobic mismatch causes protein aggregation and low yields during the reconstitution procedure, which are exacerbated in sterol-rich membranes featuring low membrane compressibility. Here, we explore new approaches to reversibly tune the sterol content of (proteo)liposomes with methyl-β-cyclodextrin (mβCD) in a dialysis setting. Maintaining (proteo)liposomes in a confined compartment minimizes loss of material during cholesterol transfer and facilitates efficient removal of mβCD. We monitor the sterol concentration in the membrane with help of the solvatochromic probe C-Laurdan, which reports on lipid packing. Using Förster resonance energy transfer, we show that cholesterol delivery to proteoliposomes induces the oligomerization of a membrane property sensor, whereas a subsequent removal of cholesterol demonstrates full reversibility. We propose that tuning membrane compressibility by mβCD-meditated cholesterol delivery and removal in a dialysis setup provides a new handle to study the impact of sterols and membrane compressibility on membrane protein structure, function, and dynamics.

Production of biomass and biomolecules in Limnospira indica PCC 8005 cultivation under magnetic fields and polymeric nanofibers

Researchers often apply physical, chemical, or biological stresses to cyanobacteria cultivation to enhance biomass production by triggering cellular adaptation mechanisms, increasing growth or boosting target compound synthesis. Static magnetic fields (SMF) offer a non-toxic, cost-effective way to modulate microalgal growth, alter biomass composition, and promote metabolite production. Polymeric nanofibers (Nano) function as a physical barrier in cultivation, while monoethanolamine (MEA) acts as a chemical absorbent, reducing CO₂ loss and enhancing biofixation. This study investigated the effects of SMF and nanofibers on the biomass yield and molecular composition of Limnospira indica PCC 8005. The combined SMF and Nano treatment achieved the highest biomass yield (5.87 ± 0.06gL⁻¹), a 28% increase compared to the control. SMF application increased protein content by 16% but reduced carbohydrate levels by 73% relative to the nanofiber-only treatment (39.58 ± 0.98% ww⁻¹). Exopolysaccharide (EPS) produced under the SMF+NanoMEA treatment contained 39.9% uronic acid, while the Nano-only treatment had the highest sulphate content (8.4%) but the lowest uronic acid concentration (25.4%). The EPS were identified as acidic, sulphated polysaccharides. SMF and nanofibers significantly enhances biomass production, alters the carbohydrate and protein proportions in biomass, and influences the composition of sugars, acids, and sulphate in exopolysaccharides.

EHBP1 suppresses liver fibrosis in metabolic dysfunction-associated steatohepatitis

Excess cholesterol accumulation contributes to fibrogenesis in metabolic dysfunction-associated steatohepatitis (MASH), but how hepatic cholesterol metabolism becomes dysregulated in MASH is not completely understood. We show that human fibrotic MASH livers have decreased EH-domain-binding protein 1 (EHBP1), a genome-wide association study (GWAS) locus associated with low-density lipoprotein (LDL) cholesterol, and that EHBP1 loss- and gain-of-function increase and decrease MASH fibrosis in mice, respectively. Mechanistic studies reveal that EHBP1 promotes sortilin-mediated PCSK9 secretion, leading to LDL receptor (LDLR) degradation, decreased LDL uptake, and reduced TAZ, a fibrogenic effector. At a cellular level, EHBP1 deficiency affects the intracellular localization of retromer, a protein complex required for sortilin stabilization. Our therapeutic approach to stabilizing retromer is effective in mitigating MASH fibrosis. Moreover, we show that the tumor necrosis factor alpha (TNF-α)/peroxisome proliferator-activated receptor alpha (PPARα) pathway suppresses EHBP1 in MASH. These data not only provide mechanistic insights into the role of EHBP1 in cholesterol metabolism and MASH fibrosis but also elucidate an interplay between inflammation and EHBP1-mediated cholesterol metabolism.

Membranal phosphatidylglycerol enhances oxygen diffusion and release from cyanobacteria

Efficient oxygen transfer is critical challenge in algae-bacteria consortia, where aerobic bacteria depend on oxygen supplied by algae for the degradation of organic pollutants. Despite the well-documented role of cyanobacterial photosynthesis in oxygen production, the mechanisms regulating oxygen diffusion and release remain poorly understood. This study investigates the abiological functions of phosphatidylglycerol (PG), a key membrane phospholipid, in modulating oxygen dynamics in Synechococcus elongates. By engineering a PG-enriched pgsA mutant strain, we observed significantly enhanced oxygen diffusion and bubble release compared to the wild-type strain. Molecular dynamics simulations revealed that PG enrichment lowers energy barriers and increases the rate of oxygen permeation across the cell membrane. Single-cell adhesion measurements using atomic force microscopy demonstrated reduced cell-bubble adhesion forces in the pgsA strain, promoting efficient oxygen bubble detachment. PG incorporation also reduced surface roughness, decreased envelope stiffness, and enhanced membrane hydrophilicity, further supporting oxygen release. Importantly, PG enrichment did not affect photosynthetic efficiency or cell growth, indicating that the observed enhancements are driven by PG's abiological functions. These findings provide new insights into the role of membrane lipids in cyanobacterial oxygen dynamics and highlight PG's potential for improving oxygen delivery in environmental applications such as wastewater treatment and aquatic ecosystem restoration.

Characterization of lipid chain order and dynamics in asymmetric membranes by solid-state NMR spectroscopy

We studied the structure and dynamics of asymmetric POPCout/(POPE/POPG)in and POPSout/(POPE/POPG)in lipid membranes. To this end, the outer layer of multilamellar POPE/POPG (molar ratio 9 : 1) vesicles was exchanged (using methyl-β-cyclodextrin) by either chain deuterated POPC-d31 or POPS-d31, for which 2H NMR order parameters were measured. As controls, we prepared symmetric POPC-d31/POPE/POPG and POPS-d31/POPE/POPG membranes of the composition of just the outer membrane of the asymmetric multilamellar vesicles and pure POPC-d31 or POPS-d31 multilamellar vesicles. Compared to symmetric membranes of the same lipid composition, chain order parameters (S) of the asymmetric preparations were higher in the upper half of the chain and lower in the lower half. This reshuffling of acyl chain order is also expressed in higher 2H NMR Zeeman order relaxation rates (R1Z) of the chain segments in asymmetric membranes indicating alterations in the elastic properties of asymmetric bilayers as inferred from plots of R1Zvs. S2. Asymmetric membranes showed increased stiffness and rigidity although the lipid acyl chain composition between the inner and outer leaflets were identical. There were no indications for chain interdigitation between the two leaflets in the NMR spectra, which led us to speculate that the interleaflet coupling could be accomplished by sensing the differences in lipid packing densities between the two leaflets. These alterations in leaflet properties should have consequences for lipid protein interaction and ultimately protein function.

Nanopesticides ecotoxicity towards traditional ones: A case of study with Daphnia magna and λ-cyhalothrin

Nanotechnology has contributed to agriculture industry with novel products to improve the targeted delivery of active ingredients (a.i.), enable gradual release, avoid premature degradation, and increase efficacy. The properties of nanopesticides make their drift and environmental behavior more unpredictable than traditional formulations. Our aim was to compare the ecotoxicity of two insecticides with λ-cyhalothrin as a.i.: a nano-based one and a traditional emulsified, considering the incidence of temperature according to climate change prospections (20 and 24 °C). We evaluated their effects on Daphnia magna survival, body stores, and butyrylcholinesterase (BChE) activity. Although after 24 h the traditional formulation had greater lethality than the nanopesticide, after 48 h this pattern was reversed. At 24 °C the lethality of both pesticides increased. BChE activity was inhibited at 24 °C by both pesticides. In general, the increase in temperature negatively affected protein and glycogen content. The traditional formulation reduced glycogen content at 24 °C. A decrease in lipid content and the whole energy budget was observed in organisms exposed to the traditional formulation at both temperatures. Although the nano-based pesticide developed a delayed toxicity, it was more lethal than the traditional one in the long term. The temperature rise worsened the pesticides effects in terms of decreased survival, BChE activity inhibition, and energy reserves depletion. The development and regulation of new eco-safer nanopesticides needs to be complemented by their ecotoxicological assessment. It is imperative to analyze their impact in the context of climate change in order to develop mitigation and adaptation strategies.

Development and thorough evaluation of a multi-omics sample preparation workflow for comprehensive LC-MS/MS-based metabolomics, lipidomics and proteomics datasets

The importance of sample preparation selection if often overlooked particularly for untargeted multi-omics approaches that gained popularity in recent years. To minimize issues with sample heterogeneity and additional freeze-thaw cycles during sample splitting, multiple -omics datasets (e.g. metabolomics, lipidomics and proteomics) should ideally be generated from the same set of samples. For sample extraction, commonly biphasic organic solvent systems are used that require extensive multi-step protocols. Individual studies have recently also started to investigate monophasic (all-in-one) extraction procedures. The aim of the current study was to develop and systematically compare ten different mono- and biphasic extraction solvent mixtures for their potential to aid in the most comprehensive metabolomics, lipidomics and proteomics datasets. As the focus was on human postmortem tissue samples (muscle and liver tissue), four tissue homogenization parameters were also evaluated. Untargeted liquid chromatography mass spectrometry-based metabolomics, lipidomic and proteomics methods were utilized along with 1D sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and bicinchoninic acid (BCA) assay results. Optimal homogenization was found to be achieved by bead-homogenizing 20 mg of muscle or liver tissue with 200 μL (1:10 ratio) Water:Methanol (1:2) using 3 × 30 s pulses. The supernatant of the homogenate was further extracted. Comprehensive ranking, taking nine different processing parameters into account, showed that the monophasic extraction solvents, overall, showed better scores compared to the biphasic solvent systems, despite their recommendation for one or all of the -omics extractions. The optimal extraction solvent was found to be Methanol:Acetone (9:1), resulting in the most comprehensive metabolomics, lipidomics and proteomics datasets, showing the potential to be automated, hence, allowing for high-throughput analysis of samples and opening the door for comprehensive multi-omics results from routine clinical cases in the future.

Platelet lipidomics indicates enhanced thrombocyte activation in patients with antiphospholipid syndrome in vivo

BACKGROUND

Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by the presence of antiphospholipid antibodies in patients with thromboembolic/thromboinflammatory events and/or obstetric complications.

OBJECTIVES

The aim of this study was to examine whether there are alterations in the platelet lipidome of APS patients in comparison with patients affected by thromboembolism without APS (control) and healthy volunteers.

METHODS

We applied quantitative mass spectrometry-based lipidomics to investigate the platelet lipidome of isolated resting and thrombin-stimulated platelets as well as platelet release in patients with APS, controls, and healthy volunteers.

RESULTS

Lipidomic data revealed an increase in lysophospholipids (LPLs) in platelets from APS patients, specifically in lysophosphatidylcholine and lysophosphatidylethanolamine species. As LPLs are cleavage products generated by phospholipase A (PLA) from the corresponding phospholipid precursor, LPL/phospholipid ratios may be employed as surrogates for PLA1 and PLA2 activities. The surrogate ratios for PLA2, which participates in the release of arachidonic acid during platelet activation, were significantly increased in APS in both resting platelets and upon thrombin-induced activation for phosphatidylcholine and phosphatidylethanolamine. The phosphatidylcholine-PLA2 surrogate ratio was found to correlate with serum levels of anti-β2-glycoprotein I and anticardiolipin immunoglobulin G. Finally, receiver operator characteristic analysis demonstrated excellent discrimination of patients with APS from controls and healthy volunteers.

CONCLUSION

These findings provide substantial evidence that platelet activation is enhanced in APS in vivo, involving the activation of PLA2.

Pre-fermentation and filtration pretreatments enhance hydrogen production from food waste through microbial electrolysis

Bioavailable organic-rich food waste (FW) is a promising feedstock for renewable hydrogen production. However, its highly suspended and complex nature presents substantial challenges for producing high-purity hydrogen in dual-chamber microbial electrolysis cells (MECs). This study examined the effects of pretreating FW through pre-fermentation and/or filtration on its microbial electrolysis. Both methods enhanced the exoelectrogenic utilization of FW, with pre-fermentation being especially effective by conditioning substrate composition, while filtration alone was less advantageous due to associated energy loss. The MECs fed with pre-fermented FW exhibited significantly higher performances, achieving the highest hydrogen yield of 1,029 mL/g chemical oxygen demand fed (39.1 % increase over raw FW) when pre-fermentation was followed by filtration. Bioanodes across all MECs were dominated by exoelectrogenic bacteria, mainly Geobacter and Desulfovibrio, with significantly greater abundance observed with pre-fermentation. These findings highlight the value of pretreatment, particularly pre-fermentation, and warrant further optimization research to maximize FW conversion into hydrogen.

Ergosterol-induced immune response in barley involves phosphorylation of phosphatidylinositol phosphate metabolic enzymes and activation of diterpene biosynthesis

Lipids play crucial roles in plant-microbe interactions, functioning as structural components, signaling molecules, and microbe-associated molecular patterns (MAMPs). However, the mechanisms underlying lipid perception and signaling in plants remain largely unknown. Here, we investigate the immune responses activated in barley (Hordeum vulgare) by lipid extracts from the beneficial root endophytic fungus Serendipita indica and compare them to responses elicited by chitohexaose and the fungal sterol ergosterol. We demonstrate that S. indica lipid extract induces hallmarks of pattern-triggered immunity (PTI) in barley. Ergosterol emerged as the primary immunogenic component and was detected in the apoplastic fluid of S. indica-colonized barley roots. Notably, S. indica colonization suppresses the ergosterol-induced burst of reactive oxygen species (ROS) in barley. By employing a multi-omics approach, which integrates transcriptomics, phosphoproteomics, and metabolomics, we provide evidence for the phosphorylation of phosphatidylinositol phosphate (PIP) metabolic enzymes and activation of diterpene biosynthesis upon exposure to fungal lipids. Furthermore, we show that phosphatidic acid (PA) enhances lipid-mediated apoplastic ROS production in barley. These findings indicate that plant lipids facilitate immune responses to fungal lipids in barley, providing new insights into lipid-based signaling mechanisms in plant-microbe interactions.

Lipidome plasticity in medium- and long-chain fatty acid oxidation disorders: Insights from dried blood spot lipidomics

Fatty acid (FA) oxidation disorders (FAOD) are characterized by accumulation of specific acylcarnitines (CAR) and FA and can lead to potentially severe complications. In this study, dried blood spots (DBS) combined with LC-MS lipidomics analysis were used to assess lipidome plasticity in medium-chain acyl-CoA dehydrogenase deficiency (MCADD), long-chain hydroxyacyl-CoA dehydrogenase deficiency (LCHADD), and very long-chain acyl-CoA dehydrogenase deficiency (VLCADD), compared to control (CT) individuals, for screening potential prognostic biomarkers. Statistically significant variations were found in CAR, biomarkers for FAOD diagnosis, but other lipid species showed variations depending on the FAOD. Common changes in all FAOD included a few phosphatidylcholine (PC) lipid species, notably an up-regulation of LPC 16:1, possibly associated with a higher risk of cardiovascular disease (CVD). In LCHADD and VLCADD, an up-regulation of odd-chain PC (PC 33:0, PC 35:4 and PC 37:4) was observed. VLCADD exhibited higher levels of odd-chain TG, while LCHADD showed an up-regulation of ceramide (Cer 41:2;O2). The increase in the Cer class has been found to be associated with neurodegeneration and may contribute to the risk of developing this condition in LCHADD. An upregulation of ether-linked PC lipid species, including plasmenyl (known as endogenous antioxidants), was observed in MCADD, possibly as a response to increased oxidative stress reported in this disorder. Overall, DBS combined with lipidomics effectively pinpoints the lipid plasticity in FAOD, highlighting potential specific biomarkers for disease prognosis that warrant further validation for their association with the development of FAOD comorbidities.

Advances in targeted liquid chromatography-tandem mass spectrometry methods for endocannabinoid and N-acylethanolamine quantification in biological matrices: A systematic review

Liquid chromatography paired with tandem mass spectrometry (LC-MS/MS) is the gold standard in measurement of endocannabinoid concentrations in biomatrices. We conducted a systematic review of literature to identify advances in targeted LC-MS/MS methods in the period 2017-2024. We found that LC-MS/MS methods for endocannabinoid quantification are relatively consistent both across time and across biomatrices. Recent advances have primarily been in three areas: (1) sample preparation techniques, specific to the chosen biomatrix; (2) the range of biomatrices tested, recently favoring blood matrices; and (3) the breadth of endocannabinoid and endocannabinoid-like analytes incorporated into assays. This review provides a summary of the recent literature and a guide for researchers looking to establish the best methods for quantifying endocannabinoids in a range of biomatrices.

Lipoxin A4/FPR2 Signaling Mitigates Ferroptosis of Alveolar Epithelial Cells via NRF2-Dependent Pathway During Lung Ischemia-Reperfusion Injury

Post-lung transplant (LTx) injury can involve sterile inflammation due to ischemia-reperfusion injury (IRI) that contributes to allograft dysfunction. In this study, we investigated the cell-specific role of ferroptosis (excessive iron-mediated cell death) in mediating lung IRI and investigated if specialized pro-resolving mediators such as Lipoxin A4 (LxA4) can protect against ferroptosis in lung IRI. Single-cell RNA sequencing analysis of lung tissue from post-LTx patients was performed, and lung IRI was evaluated in C57BL/6 (WT), formyl peptide receptor 2 knockout (Fpr2-/-) and nuclear factor erythroid 2-related factor 2 knockout (Nrf2-/-) mice using a hilar-ligation model with or without LxA4 administration. Furthermore, the protective efficacy of LxA4 was evaluated employing a murine orthotopic LTx model and in vitro studies using alveolar type II epithelial (ATII) cells. The results show differential expression of ferroptosis-related genes in post-LTx patient samples compared to healthy controls. A significant increase in the levels of oxidized lipids and a reduction in the levels of intact lipids were observed in mice subjected to IRI compared to shams. Importantly, LxA4 treatment attenuated pulmonary dysfunction, ferroptosis, and inflammation in WT mice subjected to lung IRI, but not in Fpr2-/- or Nrf2-/- mice after IRI. In the murine LTx model, LxA4 treatment increased PaO2 levels and attenuated lung IRI. Mechanistically, LxA4-mediated protection involves an increase in NRF2 activation and glutathione concentration as well as a decrease in MDA levels in ATII cells. In summary, our results collectively show that LxA4/FPR2 signaling on ATII cells mitigates ferroptosis via NRF2 activation and protects against lung IRI.

Role of glucuronoxylomannan and steryl glucosides in protecting against cryptococcosis

The development of vaccines for fungal diseases, including cryptococcosis, is an emergent line of research and development. In previous studies, we showed that a Cryptococcus mutant lacking the SGL1 gene (∆sgl1) accumulates certain glycolipids called steryl glucosides (SGs) on the fungal capsule, promoting an effective immunostimulation that totally protects the host from a secondary cryptococcal infection. However, this protection is lost when the cryptococcal capsule is absent in the ∆sgl1 background. The cryptococcal capsule is mainly composed of glucuronoxylomannan (GXM), a polysaccharide microfiber consisting of glucuronic acid, xylose, and mannose linked by glycosidic bonds forming specific triads. In this study, we engineered cells to lack each of the GXM components and tested the effect of these deletions on protection under the condition of SG accumulation. We found that glucuronic acid and xylose are required for protection, and their absence abrogates the production of IFNγ and IL-17A by γδ T cells, which are necessary stimulants for the protective phenotype of the ∆sgl1. We analyzed the structure of the GXM microfibers and found that although the deletion of SGL1 only slightly affects the size and distribution of these microfibers, it significantly changes the ratio of mannose to other components. In conclusion, this study identifies the structural modifications that the deletion of SGL1 and the consequent accumulation of SGs impart to the GXM structure of C. neoformans. This provides significant insights into the protective mechanisms mediated by SG accumulation on the capsule, with important implications for the future development of an efficacious cryptococcal vaccine.IMPORTANCECryptococcus neoformans is an encapsulated fungus that causes invasive fungal infections with high morbidity and mortality in susceptible patients. With increasing drug resistance and high toxicity of current antifungal drugs, there is a need for alternative therapeutic strategies, such as a cryptococcal vaccine. In this study, we identify the necessary capsular components and their structural organization required for a cryptococcal vaccine to protect the host against challenge with a virulent strain. These capsular components are glucuronic acid, xylose, and mannose, and they work together with certain glycolipids called steryl glucosides (SGs) to stimulate host immunity. Interestingly, SGs on the capsule may favor the formation of small capsular microfibers organized in specific mannose triads. Thus, the results of this paper are important because they identify a mechanism by which SGs affect the structure of the cryptococcal capsule, with important implications for the future development of a cryptococcal vaccine using capsular components and SGs.

Mitochondrial membrane hyperpolarization modulates nuclear DNA methylation and gene expression through phospholipid remodeling

Maintenance of the mitochondrial inner membrane potential (ΔΨm) is critical for many aspects of mitochondrial function. While ΔΨm loss and its consequences are well studied, little is known about the effects of mitochondrial hyperpolarization. In this study, we used cells deleted of ATP5IF1 (IF1), a natural inhibitor of the hydrolytic activity of the ATP synthase, as a genetic model of increased resting ΔΨm. We found that the nuclear DNA hypermethylates when the ΔΨm is chronically high, regulating the transcription of mitochondrial, carbohydrate and lipid genes. These effects can be reversed by decreasing the ΔΨm and recapitulated in wild-type (WT) cells exposed to environmental chemicals that cause hyperpolarization. Surprisingly, phospholipid changes, but not redox or metabolic alterations, linked the ΔΨm to the epigenome. Sorted hyperpolarized WT and ovarian cancer cells naturally depleted of IF1 also showed phospholipid remodeling, indicating this as an adaptation to mitochondrial hyperpolarization. These data provide a new framework for how mitochondria can impact epigenetics and cellular biology to influence health outcomes, including through chemical exposures and in disease states.

PPARα regulates ER-lipid droplet protein Calsyntenin-3β to promote ketogenesis in hepatocytes

Ketogenesis requires fatty acid flux from intracellular (lipid droplets) and extrahepatic (adipose tissue) lipid stores to hepatocyte mitochondria. However, whether interorganelle contact sites regulate this process is unknown. Recent studies have revealed a role for Calsyntenin-3β (CLSTN3β), an endoplasmic reticulum-lipid droplet contact site protein, in the control of lipid utilization in adipose tissue. Here, we show that Clstn3b expression is induced in the liver by the nuclear receptor PPARα in settings of high lipid utilization, including fasting and ketogenic diet feeding. Hepatocyte-specific loss of CLSTN3β in mice impairs ketogenesis independent of changes in PPARα activation. Conversely, hepatic overexpression of CLSTN3β promotes ketogenesis in mice. Mechanistically, CLSTN3β affects LD-mitochondria crosstalk, as evidenced by changes in fatty acid oxidation, lipid-dependent mitochondrial respiration, and the mitochondrial integrated stress response. These findings define a function for CLSTN3β-dependent membrane contacts in hepatic lipid utilization and ketogenesis.

Paraoxonase-like APMAP maintains endoplasmic-reticulum-associated lipid and lipoprotein homeostasis

Oxidative stress perturbs lipid homeostasis and contributes to metabolic diseases. Though ignored when compared with mitochondrial oxidation, the endoplasmic reticulum (ER) generates reactive oxygen species requiring antioxidant quality control. Using multi-organismal profiling featuring Drosophila, zebrafish, and mammalian hepatocytes, here we characterize the paraoxonase-like C20orf3/adipocyte plasma-membrane-associated protein (APMAP) as an ER-localized antioxidant that suppresses ER lipid oxidation to safeguard ER function. APMAP-depleted cells exhibit defective ER morphology, ER stress, and lipid peroxidation dependent on ER-oxidoreductase 1α (ERO1A), as well as sensitivity to ferroptosis and defects in ApoB-lipoprotein homeostasis. Similarly, organismal APMAP depletion in Drosophila and zebrafish perturbs ApoB-lipoprotein homeostasis. Strikingly, APMAP loss is rescued with chemical antioxidant N-acetyl-cysteine (NAC). Lipidomics identifies that APMAP loss elevates phospholipid peroxidation and boosts ceramides-signatures of lipid stress. Collectively, we propose that APMAP is an ER-localized antioxidant that promotes lipid and lipoprotein homeostasis in the ER network.

Elucidating mechanisms of action of environmental contaminants from Doce River in Brazilian fish embryos using metabolomics and chemometric methods

Mining and other essential economic activities have a long historical contamination impact on diverse aquatic environments, such as the Doce River Basin (DRB), in Southeast Brazil. High concentrations of metals combined with organic chemicals released from multiple sources of contaminants may trigger complex toxicity pathways that are complicated to interpret and distinguish. This study aimed to investigate mechanisms of toxicity of environmental chemicals from DRB using a comprehensive untargeted LC-HRMS metabolomics approach (data-independent acquisition of all ion-fragmentation mode), in fish embryos (Rhamdia quelen) exposed to complex chemical mixtures. The Regions of Interest (ROI) Multivariate Curve Resolution (MCR) approach was applied to compress and resolve data-independent acquisition (DIA) LC-MS/MS complex datasets mode. Fish embryos exposed for 96 h to 6 treatment sample groups showed a distinct pattern of responses when compared to controls, with downregulated essential metabolites, such as amino acids, as a main response, especially for metal exposure. Organic contaminants extracted from sediments combined with inorganic elements have shown non-additive effects, with inorganics possibly exerting greater influence on metabolic responses. The results helped to investigate and distinguish the effects of different complex mixtures of environmental chemicals on fish embryo samples. ROIMCR approach is shown to be a suitable strategy for the analysis of large metabolomics-derived data in the investigation of the effects of different classes of environmental chemicals on aquatic biota and ecosystems.

Dietary targeting of TRPM8 rewires macrophage immunometabolism reducing colitis severity

The interplay between diet, host genetics, microbiota, and immune system has a key role in the pathogenesis of inflammatory bowel disease (IBD). Although the causal pathophysiological mechanisms remain unknown, numerous dietary nutrients have been shown to regulate gut mucosal immune function, being effective in influencing innate or adaptive immunity. Here, we proved that transient receptor potential melastatin 8 (TRPM8), a non-selective cation channel, mediates LPS- evoked Ca2+ influx in macrophages leading to their activation. Additionally, we showed that TRPM8 is selectively blocked by the dietary flavonoid luteolin, which induced a pro-tolerogenic phenotype in pro-inflammatory macrophages. Accordingly, genetic deletion of Trpm8 in macrophages caused a deficit in the activation of pro-inflammatory metabolic and transcriptional reprogramming, leading to reduced production of key pro-inflammatory cytokines such as interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α. The TRPM8 anti-inflammatory effect was found to be dependent on lactate which in turn induces IL-10 gene expression. Adoptive transfer of TRPM8-deficient bone marrow in wild-type mice improved intestinal inflammation in a model of colitis. Accordingly, oral administration of luteolin protected mice against colitis through an impairment in the innate immune response. Our study reveals the potential of targeting TRPM8 through specific nutrient interventions to regulate immune function in sub-clinical scenarios or to treat inflammatory diseases, primarily driven by chronic immune responses, such as IBD.

Effects of elevated temperature on gene expression, energy metabolism, and physiology in brown trout, Salmo trutta

Given the imminent threat of global warming and rising water temperatures in Austria, this study investigated the effects of elevated temperature on gene expression, energy reserves, and cellular energy status in brown trout (Salmo trutta), a species particularly sensitive to increasing water temperature. A total of 250 fish were placed in four stream channels under flow-through conditions. Two channels were maintained at 9 °C as controls, while the other two had their temperature gradually increased to 20 °C over seven days and then maintained at 20 °C for 21 days. Sampling was conducted on day 1, after the temperature reached 20 °C, and the last day of high-temperature exposure on day 21. At each sampling point growth, hepatosomatic index and the fat content of the viscera were measured and/or calculated, and liver samples were taken for gene expression and metabolite analyses. Elevated temperature significantly increased the expression of genes related to cellular stress response (hsp70, hsp90 aa1, cat, and casp8) compared to controls. However, there was no significant difference in the expression of genes associated with lipid and carbohydrate metabolism (d5fad and pfkfb4). Furthermore, there was a decrease in energy storage indicated by a decrease in the hepatosomatic index, glycogen, triglycerides and ATP in the liver as well as the fat content of the viscera. Cellular energy status also significantly decreased, as indicated by the calculated adenylate energy charge. Physiologically, this culminated in suppression of growth in the treatment group after 21 days. This study shows that elevated temperature leads to significant trade-offs in brown trout, which may lead to ecological consequences over the long run. These findings offer critical insights into the physiological impacts of elevated temperature that help evaluate the species' acclimation to rising water temperature and inform the development of effective conservation strategies in a warming world.

Potentiation of macrophage Piezo1 by atherogenic 7-ketocholesterol

The mechanosensitive ion channel Piezo1 present in endothelial and smooth muscle cells, as well as in macrophages, is emerging as a novel, important player in the etiology of atherosclerosis. Here, we show that myeloid-specific deficiency of Piezo1 in atherogenic Ldlr-/- mice reduces plaque formation. Moreover, chronic oxLDL, as well as its main oxysterol 7-ketocholesterol (7-KC), promotes Piezo1 opening by pressure stimulation in both mouse macrophages and transfected HEK cells. 7-KC dramatically enhances Piezo1 current amplitude and slows down inactivation and deactivation. This up-modulation involves an increase in Piezo1 expression, as well as a potentiation of mechanical gating that depends on membrane cholesterol depletion and decreased order. By contrast, Piezo1 is inhibited by the athero-protective free docosahexaenoic acid, either without or with 7-KC. Altogether, these findings indicate that macrophage Piezo1 is differentially modulated by pro- and anti-atherogenic lipids, pointing to the role of Piezo1 and its potentiation by oxysterols in atherosclerosis.

Structural robustness and temporal vulnerability of the starvation-responsive metabolic network in healthy and obese mouse liver

Adaptation to starvation is a multimolecular and temporally ordered process. We sought to elucidate how the healthy liver regulates various molecules in a temporally ordered manner during starvation and how obesity disrupts this process. We used multiomic data collected from the plasma and livers of wild-type and leptin-deficient obese (ob/ob) mice at multiple time points during starvation to construct a starvation-responsive metabolic network that included responsive molecules and their regulatory relationships. Analysis of the network structure showed that in wild-type mice, the key molecules for energy homeostasis, ATP and AMP, acted as hub molecules to regulate various metabolic reactions in the network. Although neither ATP nor AMP was responsive to starvation in ob/ob mice, the structural properties of the network were maintained. In wild-type mice, the molecules in the network were temporally ordered through metabolic processes coordinated by hub molecules, including ATP and AMP, and were positively or negatively coregulated. By contrast, both temporal order and coregulation were disrupted in ob/ob mice. These results suggest that the metabolic network that responds to starvation was structurally robust but temporally disrupted by the obesity-associated loss of responsiveness of the hub molecules. In addition, we propose how obesity alters the response to intermittent fasting.

Belowground energy fluxes determine tree diversity effects on above- and belowground food webs

Worldwide tree diversity loss raises concerns about functional and energetic declines across trophic levels. In this study, we coupled 160 above- and belowground food webs, quantifying energy fluxes to microorganisms and invertebrates in a tree-mycorrhiza diversity experiment, to test how tree diversity affects fluxes of energy above and below the ground. The experiment differentiates three mycorrhizal type treatments: only AM tree species (with arbuscular mycorrhizae), only EcM tree species (with ectomycorrhizae; one, two, and four tree species), or mixtures of both AM and EcM tree species (AM+EcM; two and four tree species). Our results indicate that most energy initially flowed through belowground communities, with soil microorganisms contributing 97.7% of total energy and belowground fauna accounting for 60.9% of energy to animals. Consequently, belowground fauna fueled surface (62.3% of predation) and aboveground (30.5% of predation) predators. Tree diversity increased ecosystem multifunctionality (indicated by total and averaged energy fluxes) by ∼30% and energy across most trophic levels in EcM tree communities, while it shifted food webs from fast (such as bacterial-dominated) to slow (such as fungal-dominated) channels in AM tree communities. Tree diversity primarily impacted energy fluxes through belowground communities and strengthened the coupling of above- and belowground food webs, with increasing importance of belowground prey for predators at the soil surface and above the ground. These findings highlight that tree diversity and mycorrhizal types drive above- and belowground ecosystem functioning via belowground energy fluxes.

Identification of novel candidate genes for regulating oil composition in soybean seeds under environmental stresses

Introduction

A key objective of soybean breeding programs is to enhance nutritional quality for human and animal consumption, with improved fatty acid (FA) composition for health benefits, and expand soybean use for industrial applications.

Methods

We conducted a metabolite genome-wide association study (mGWAS) to identify genomic regions associated with changes in FA composition and FA ratios in soybean seeds influenced by environmental factors. This mGWAS utilized 218 soybean plant introductions (PIs) grown in two field locations in Virginia over two years.

Results

The mGWAS revealed that 20 SNPs were significantly associated with 21 FA ratios, while additional suggestive SNPs were found for 36 FA ratios, highlighting potential quantitative trait loci linked to FA composition.

Discussion

Many of these SNPs are located near or within the genes related to phytohormone-mediated biotic and abiotic stress responses, suggesting the involvement of environmental factors in modulating FA composition in soybean seeds. Our findings provide novel insights into the genetic and environmental factors influencing FA composition in oilseeds. This research also lays the foundation for developing stable markers to develop soybean cultivars with tailored FA profiles for different practical applications under variable growth conditions.

Synergistic Effects of Selected Nonthermal Technologies Combined with Soursop Leaf Extract on the Quality and Shelf Life of Refrigerated Pacific White Shrimp

The effectiveness of multi-targeted treatments including pulsed electric field (PEF), soursop leaf extract (SLE), vacuum impregnation (VI), and modified atmosphere packaging (MAP), with and without cold plasma (CP) treatment, on the quality and shelf life of Pacific white shrimp (Penaeus vannamei) during refrigerated storage for 21 days was investigated. PEF inhibited melanosis and reduced the initial bacterial load, as evidenced by lower melanosis scores and total bacterial counts in the treated samples. Integrating 1% SLE through VI effectively lowered color alteration, retarded melanosis, and preserved textural integrity in the SLE-treated samples (p < 0.05). SLE1 (1%) significantly reduced lipid oxidation, as witnessed by lower thiobarbituric acid reactive substances (p < 0.05) and minimal fatty acid profile changes. MAP3, comprising CO2/N2/Ar (60%/30%/10%), combined with CP treatment, ensured microbiological quality and maintained total viable count within the acceptable limit (6 Log CFU/g) throughout the storage time of 21 days. Notably, the PEF-SLE1-VI-MAP3-CP sample exhibited superior quality preservation, as shown by a lower pH and total volatile base content than the others. Sensory evaluation confirmed that the PEF-SLE1-VI-MAP3-CP sample remained sensorially acceptable during storage. Thus, this multi-hurdle approach demonstrated the synergistic potential of integrating nonthermal processing technologies with plant extracts, contributing to the extended shelf life and safety of the refrigerated shrimp for up to 21 days.

Effectiveness of red propolis extract as a natural antioxidant in frozen lamb burgers

The antioxidant effects of red propolis extract were evaluated in lamb burgers stored for 120 days at -18 °C. The treatments prepared were CON (control, no antioxidant), ERI (500 mg/kg sodium erythorbate), P1800 (1800 mg/kg propolis extract), and P3600 (3600 mg/kg propolis extract).The analyses performed were proximate composition (moisture, protein, fat, and ash), texture, and sensory acceptance (day 0); pH, color profile (L*, a*, b*), weight loss of cooking (WLC), diameter reduction, TBARS, and peroxide index (0, 30, 60, 90, and 120 days); and fatty acid profile and volatile compounds (0 and 120 days). No treatment was associated with a change in the proximate composition. Most texture parameters in treatments P1800 and P3600 were lower (P < 0.05), and it can be concluded that the extract favors the improvement of this sensory attribute, making the hamburgers softer. The WLC was higher in the treatments where the extract was used; however, the reduction of the diameter of the hamburgers was lower, an important aspect for consumers. The extract retarded lipid oxidation during storage, especially P3600, which presented the lowest level of TBARS (1.37 mg MDA/kg) and the peroxide index (5.69 mEq g of O2) on day 120. The presence of volatile compounds derived from lipid oxidation was more evident in the CON and ERI treatments, showing the efficiency of natural antioxidants used in the P1800 and P3600 treatments. It is concluded that red propolis represents an excellent alternative for replacement of synthetic antioxidants with natural products in lamb hamburgers.

Phytochemical diversity and biological activities of Hypericum japonicum and Hypericum sampsonii: potential for natural product-based food applications

This study characterizes two species of the genus Hypericum to envisage their applicability as effective and versatile functional foods, dietary supplements, and food preservatives. A wide phenolic composition was found in both extracts, highlighting flanovoids for H. japonicum and xanthones for H. sampsonii. Moreover, anthocyanins were analyzed for the first time in the latter plant. Antioxidant capacity was highlighted by oxidative hemolysis inhibition assay (OxHLIA), where H. japonicum was more effective (lower EC50) than antioxidant Trolox (16.3 < 21.8 μg/mL). H. sampsonii extract inhibited lipid peroxidation in the thiobarbituric acid reactive substances (TBARS) method (EC50 = 17.05 μg/mL) compared to Trolox (EC50 = 5.8 μg/mL). H. japonicum antibacterial activity showed a minimum inhibitory concentration (MIC) of 0.007 mg/mL, even lower than the control. These results indicate the bioactive potential of both extracts, as well as the importance of evaluating the food-related bioactive components of medicinal plants and the mechanisms involved in their bioactivities.

Spatial Metabolomics and Lipidomics in Kidney Disease

Kidney disease is a global health issue that affects over 850 million people, and early detection is key to preventing severe disease and complications. Kidney diseases are associated with complex and dysregulation of lipid metabolism. Spatial metabolomics through mass spectrometry imaging (MSI) enables spatial mapping of the lipids in tissue and includes a variety of techniques that can be used to image lipids. In the kidney, MSI studies often seek to resolve individual functional tissue units such as glomeruli and proximal tubules. Several different MSI techniques, such as matrix-assisted laser desorption/ionization (MALDI) and desorption electrospray ionization (DESI), have been used to characterize lipids and small molecules in chronic kidney disease, acute kidney injury, genetic kidney disease, and cancer. In this review we provide several examples of how spatial metabolomics data can provide critical information concerning the localization of changes in various disease states. Additionally, when combined with pathology, transcriptomics, or proteomics, the metabolomic changes can illuminate underlying mechanisms and provide new clinical insights into disease mechanisms. Semin Nephrol 36:x-xx © 20xx Elsevier Inc. All rights reserved.

Sex differences in lipid profiles of visceral adipose tissue with obesity and gonadectomy

In obesity, adipose tissue (AT) expansion is accompanied by chronic inflammation. Altered lipid composition in the visceral or gonadal white AT (GWAT) directly drive AT macrophage (ATM) accumulation and activation to a proinflammatory phenotype. Sex steroid hormones modulate visceral vs subcutaneous lipid accumulation that correlates with metabolic syndrome, especially in men and post-menopausal women who are more prone to abdominal obesity. Prior studies demonstrated sex differences in GWAT lipid species in HFD-fed mice, but the role of sex hormones is still unclear. We hypothesized that sex hormone alterations with gonadectomy (GX) would further impact lipid composition in the obese GWAT. Untargeted lipidomics of obese GWAT identified sex differences in phospholipids, sphingolipids, sterols, fatty acyls, saccharo-lipids and prenol-lipids. Males had significantly more precursor fatty acids (palmitic, oleic, linoleic and arachidonic acid) than females and GX mice. Targeted lipidomics for fatty acids and oxylipins in the HFD-fed male and female GWAT stromal vascular fraction (SVF) identified higher omega-6 to omega-3 free fatty acid profile in males and differences in polyunsaturated fatty acids (PUFAs)-derived prostaglandins, thromboxanes and leukotrienes. Both obese male and female GWAT SVF showed increased levels of arachidonic acid (AA) derived oxylipins compared to their lean counterparts. Bulk RNA sequencing of sorted GWAT ATMs highlighted sex and diet differences in PUFA and oxylipin metabolism genes. These findings of sexual dimorphism in both stored lipid species and PUFA derived mediators with diet and GX emphasize sex-differences in lipid metabolism pathways that drive inflammation responses and metabolic disease risk in obesity.

Peroxisomal membrane protein PMP70 confers drug resistance in colorectal cancer

Metabolic reprogramming is a key contributor to cancer therapeutic resistance. Peroxisomes are highly metabolic organelles essential for lipid metabolism and reactive oxygen species (ROS) turnover. Recent studies pointed out that targeting peroxisomal genes could be a promising strategy for treating therapy-resistant cells. However, the role of peroxisomes in CRC chemoresistance remains largely unexplored. This study aimed to investigate the function of peroxisomes in CRC chemoresistance and uncover the underlying mechanisms. Our results showed that the protein level of peroxisome marker PMP70 was strongly correlated with oxaliplatin (LOHP)-treated tumor recurrence in CRC. LOHP was confirmed to induce pexophagy in CRC cells, whereas LOHP-resistant cells maintained stable peroxisome levels and resisted this selective autophagy. Moreover, depletion of PMP70 significantly reduced the viability of resistant CRC cells in response to LOHP, both in vitro and in vivo. Mechanistically, PMP70 acted as a potential protector against excessive lipid peroxidation (LPO) in PMP70High and LOHP-resistant CRC cells. Additionally, PMP70-depleted cells exhibited an altered metabolic profile, characterized by reduced neutral lipids, fewer lipid droplets (LDs), and cell cycle arrest, indicating that PMP70 downregulation resulted in metabolic impairment. In conclusion, our study unveiled the pivotal role of PMP70-mediated peroxisomal functions in conferring chemoresistance, particularly in the context of LOHP resistance in CRC.

Aeromonas caviae subsp. aquatica subsp. nov., a New Multidrug-Resistant Subspecies Isolated from a Drinking Water Storage Tank

The increasing prevalence and dissemination of multidrug-resistant bacteria represent a serious concern for public health. Aeromonas caviae is a pathogenic microorganism that causes a wide spectrum of diseases in fish and humans and is often associated with aquatic environments and isolated from foods and animals. Here, we present the isolation and characterization of the V15T strain isolated from a drinking water storage tank in Rio de Janeiro, Brazil. The V15T strain has a genome length of 4,443,347 bp with an average G + C content of 61.78% and a total of 4028 open reading frames. Its genome harbors eight types of antibiotic resistance genes (ARGs) involving resistance to beta-lactamases, macrolides, and quinolones. The presence of blaMOX-6, blaOXA-427/blaOXA-504, and mutations in parC were detected. In addition, other ARGs (macA, macB, opmH, and qnrA) and multidrug efflux pumps (such as MdtL), along with several resistance determinants and 106 genes encoding virulence factors, including adherence (polar and lateral flagella), secretion (T2SS, T6SS), toxin (hlyA), and stress adaptation (katG) systems, were observed. The genome sequence reported here provides insights into antibiotic resistance, biofilm formation, evolution, and virulence in Aeromonas strains, highlighting the need for more public health attention and the further monitoring of drinking water systems. Also, the results of physiological and phylogenetic data, average nucleotide identity (ANI) calculation, and digital DNA-DNA hybridization (dDDH) analysis support the inclusion of the strain V15T in the genus Aeromonas as a new subspecies with the proposed name Aeromonas caviae subsp. aquatica subsp. nov. (V15T = P53320T). This study highlights the genomic plasticity and pathogenic potential of Aeromonas within household drinking water systems, calling for the revision of water treatment protocols to address biofilm-mediated resistance and the implementation of routine genomic surveillance to mitigate public health risks.

Polyphenol blend enhances zootechnical performance, improves meat quality, and reduces the severity of wooden breast in broiler chickens

This study investigated the effects of a commercial polyphenol blend on broiler performance, meat quality, carcass traits, and the incidence of pectoral myopathies. Broilers (1-42 days old) were allocated to four treatments: T1 (control, basal diet), T2 (250 g/ton polyphenol blend), T3 (500 g/ton), and T4 (1,000 g/ton), with eight replicates of 40 birds each. All diets were corn-soy based, isonutritional, and formulated to meet age-specific nutritional requirements. Parameters assessed at 21, 28, 35, and 42 days included antioxidant potential, growth performance, myopathy incidence, carcass yield, allometric growth, muscle morphometry, meat quality, and lipid profile. Optimal performance was observed at a supplementation level of 514 g/ton of polyphenols. While carcass yield remained unaffected, birds fed 500 g/ton exhibited delayed breast growth relative to other body parts, suggesting modulated allometric growth. Polyphenol supplementation reduced breast muscle fiber size, increased fiber density, and lowered the severity of wooden breast without influencing the incidence of white striping. Improved meat tenderness was evident through reduced cooking weight loss and enhanced shear force. Antioxidant status improved in plasma, muscle, and liver tissues, and the muscle lipid profile was favorably altered. In conclusion, the polyphenol blend enhanced broiler zootechnical performance, alleviated wooden breast severity, and improved meat quality and tenderness.

Meat Quality of Dairy and Dairy × Beef Steers Reared in Two Production Systems Based on Forages and Semi-Natural Pastures

To safeguard an agricultural landscape with high biodiversity, livestock grazing on semi-natural pastures is crucial, and steers are well suited to such production systems. This study compared meat quality, including technological traits, sensory attributes, and fatty acid composition, of purebred dairy steers (D) and dairy × beef crossbreed steers (C), reared in two distinct production systems. Sixty-four steers (thirty-two per breed type) were included. Half were kept in a production system that had relatively high feed intensity (H), with one grazing summer on semi-natural pastures and slaughtered at 21 months of age. The other half were kept in a production system that had low feed intensity (L), with two grazing summers on semi-natural pastures and slaughtered at 28 months. Colour, water holding capacity, Warner-Bratzler shear force, sensory attributes, and fatty acid profiles were measured on the Musculus longissimus lumborum. Meat from L steers with two grazing seasons was darker (p = 0.003) and contained a higher proportion of unsaturated fatty acids (p = 0.006) than meat from more intensively reared H steers. Meat from C steers was perceived as having a coarser fibre structure (p = 0.022) with an acidic odour (p = 0.040) compared to D steers. Additionally, cooked meat from L steers was evaluated as having a pinker appearance by an analytical sensory panel (p = 0.008). In summary, breed type and production system had no major effect on technological and sensory attributes for forage and pasture-fed steers, but fatty acid composition was improved with more unsaturated lipids in meat from L steers.

Following phospholipid transfer through the OmpF3-MlaA-MlaC lipid shuttle with native mass spectrometry

The maintenance of lipid asymmetry (Mla) system in gram-negative bacteria transfers phospholipids between the outer and inner membrane to maintain the outer membrane asymmetry. Misplaced phospholipids are extracted from the outer leaflet of the outer membrane by MlaA, transferred to the periplasmic lipid transporter MlaC, and shuttled to the inner membrane. We set out to investigate the lipid transfer between MlaA and MlaC using native mass spectrometry, with the aim of determining the lipid preferences of MlaC and whether MlaA preselected lipids for MlaC. First, we characterized the lipids that copurified with overexpressed MlaC, phosphatidylglycerol (PG), and phosphatidylethanolamine (PE), and following delipidation noted a headgroup-independent enrichment of cyclopropane lipids. Under native expression conditions, we found that PG is three-fold enriched on MlaC compared to its abundance in the membrane. Next, we isolated and characterized OmpF3-MlaA complexes and demonstrated their ability to enhance loading of delipidated MlaC with bacterial and nonbacterial phospholipids. We then captured the intact ternary lipid shuttle (OmpF3-MlaA-MlaC) and demonstrated that PG dissociates this transient complex, releasing lipid-bound MlaC. Together our results point to a high population of endogenous PG on periplasmic MlaC, which likely arises from disassembly of the lipid shuttle to maintain lipid asymmetry for cell viability.

Nuclear envelope-associated lipid droplets are enriched in cholesteryl esters and increase during inflammatory signaling

Cholesteryl esters (CEs) and triacylglycerols (TAGs) are stored in lipid droplets (LDs), but their compartmentalisation is not well understood. Here, we established a hyperspectral stimulated Raman scattering microscopy system to identify and quantitatively assess CEs and TAGs in individual LDs of human cells. We found that nuclear envelope-associated lipid droplets (NE-LDs) were enriched in cholesteryl esters compared to lipid droplets in the cytoplasm. Correlative light-volume-electron microscopy revealed that NE-LDs projected towards the cytoplasm and associated with type II nuclear envelope (NE) invaginations. The nuclear envelope localization of sterol O-acyltransferase 1 (SOAT1) contributed to NE-LD generation, as trapping of SOAT1 to the NE further increased their number. Upon stimulation by the pro-inflammatory cytokine TNFα, the number of NE-LDs moderately increased. Moreover, TNFα-induced NF-κB nuclear translocation was fine-tuned by SOAT1: increased SOAT1 activity and NE-LDs associated with faster NF-κB translocation, whereas reduced SOAT1 activity and NE-LDs associated with slower NF-κB translocation. Our findings suggest that the NE is enriched in CEs and that cholesterol esterification can modulate nuclear translocation.

Biochemical characterization and mutational analysis of lysophosphatidic acid acyltransferases of Escherichia coli highlighting their involvement in the generation of membrane phospholipid diversity

Lysophosphatidic acid acyltransferase (LPAAT) is an enzyme responsible for the second acylation step of phospholipid biosynthesis and transforms lysophosphatidic acid to phosphatidic acid, a universal precursor of various phospholipids. In addition to the well-studied plsC-encoded LPAAT (EcPlsC), we previously found that Escherichia coli has another LPAAT that is encoded by yihG (EcYihG). EcPlsC and EcYihG are integral membrane proteins and have never been solubilized and purified in their active form. To better understand the difference in their enzymatic functions and how the two paralogs differently contribute to lipid diversity, we established a method to purify both enzymes in their active form and comparatively analysed their biochemical characteristics. Our findings illustrate that EcPlsC possesses the highest activity at pH 8.0 and 37°C with selectivity for unsaturated fatty acyl-CoAs (e.g. palmitoleoyl-CoA), whereas EcYihG works optimally at pH 7.5 and 30°C and prefers saturated fatty acyl-CoAs (e.g. myristoyl-CoA). In addition, we performed a mutational analysis based on AlphaFold2 models and revealed that one residue, which is located at the putative acyl-donor-selectivity tunnel entrance, plays a pivotal role in selecting acyl donor substrates. This provides new insights into how LPAATs recognize specific fatty acyl groups and incorporate them into membrane phospholipids.

Investigation on the Lipid Profile of Ripened Pu-erh Tea and Relationships Between Their Changes and Key Aromatic Volatiles

Ripened Pu-erh tea is a special tea with unique flavor and obtained by solid fermentation of microorganisms. This work aimed to investigate the changes of lipid metabolites during fermentation and the association between lipids and the aroma of ripened Pu-erh tea based on ultra-high-performance liquid chromatography-high resolution mass spectrometry and GC-MS. A total of 217 lipids and lipid-soluble substances covering 19 subclasses were detected and characterized. Compared with green tea, black tea, and raw Pu-erh tea, ripened Pu-erh tea showed the highest levels of fatty acids. The contents of 36 lipids varied remarkably with fermentation time, and thus these compounds were screened as differential metabolites. These changes were mainly caused by the degradation of glycerophospholipids (folds change: 0.48-0.13) and the formation of fatty acids (folds change: 5.2-11.2). Results of Pearson correlation analysis showed that a few of the aromatic volatiles, including 2-octenal, 3,5-octadien-2-one, 2,4-heptadienal, and 2,6-nonadienal showed obvious negative correlations with phosphatidylcholine, phosphatidylethanolamine, and phosphatidylinositol, but significant positive correlations with fatty acids 18:2 and 18:1. This study provided a further understanding of the lipid composition of ripened Pu-erh and their changes during tea production.

Human PHOSPHO1 exhibits phosphatidylcholine- and phosphatidylethanolamine-phospholipase C activities and interacts with diacylglycerol kinase δ

Phosphatidylcholine- and phosphatidylethanolamine-specific phospholipase C (PC-PLC and PE-PLC) activities, which generate diacylglycerol (DG) and are tricyclodecan-9-yl-xanthogenate (D609)-sensitive, have been detected in both the membrane and cytosolic fractions. We have previously demonstrated that sphingomyelin synthase isozymes, which are transmembrane proteins, exhibit PC-/PE-PLC activities. However, mammalian cytosolic PC-PLC and PE-PLC remain unidentified. Here, we demonstrated that phosphatase orphan 1 (PHOSPHO1), a cytosolic protein, exhibits D609-sensitive PC-PLC and PE-PLC activities. Moreover, the overexpression of PHOSPHO1 in HEK293 cells significantly increased the levels of cellular saturated and/or monounsaturated fatty acid-containing DG. Furthermore, DGKδ cosedimented and colocalized with PHOSPHO1. Collectively, these in vitro findings provide, for the first time, a promising candidate for the long-sought cytosolic PC-/PE-PLC, which may act as DG supply enzyme upstream of DGKδ.

Identification and expression of nuclear receptor genes during nutritive phagocyte development in sea urchin Mesocentrotus nudus gonads

The role of the endocrine system during synthesis of the nutrients (e.g., proteins, lipids, polysaccharides) in the gonad in sea urchins is imperfectly understood. We identify genes encoding nuclear receptors (NRs) involved in the development of nutritive phagocytes of the sea urchin Mesocentrotus nudus, and investigate their gene expression patterns during this time. RNA-seq analysis was performed on immature gonads using a next-generation sequencer. A total of 7,651,421 quality-controlled reads obtained using an Ion PGM sequencer were assembled into 175,092 contigs. BLASTn analysis identified 20 NR genes potentially involved in the development of nutritive phagocytes. Expression analyses revealed levels of four NR genes to increase during the development of nutritive phagocytes. These results indicate that these 20 NR genes have physiological functions in gonadal growth, and that 4 NR genes mainly control the expression of genes involved in the synthesis and metabolism of proteins, lipids, and polysaccharides during cellular proliferation in sea urchin gonads.

Peroxisomal biogenesis factor 11 as a novel target to trigger lipid biosynthesis and salt stress resistance in oleaginous Tetradesmus obliquus

To overcome economic challenges in microalgal biofuel production, this study investigates the overexpression of peroxisome-localized peroxisomal biogenesis factor 11 (PEX11) to enhance lipid biosynthesis and improve salt stress resistance in Tetradesmus obliquus, aiming to advance microalgal biofuel production. Transgenic strains PEX11-2-1 and PEX11-2-2 exhibited a 2.13- and 2.51-fold increase in neutral lipid content and more cellular lipid droplets compared to WT, along with lipid yield and biomass escalating to 255.45 and 815.15 mg/L, respectively. This enhancement resulted from the redistribution of carbon precursors, increased intracellular reactive oxygen species, enhanced NADPH synthesis, and upregulation of lipid synthesis genes. Additionally, PEX11 improved salt stress tolerance by upregulating the expression of stress-responsive genes, including SnRK2 and PYRC. Fatty acid profile alterations, with increases in saturated fatty acids C16:0 and monounsaturated fatty acids C18:1, and decreases in polyunsaturated fatty acids, facilitated high-quality biofuel production. These findings highlight novel insights for advancing microalgae-based biorefinery.