Mass Spectrometry-based Lipidomics Research Articles

Critical overview of mass spectrometry-based lipidomics approach for evaluating lipid oxidation in foods

Critical overview of mass spectrometry-based lipidomics approach for evaluating lipid oxidation in foods

Prognostic significance of plasma molecular lipid species in coronary artery disease patients: A prospective cohort study

Abstract Background Circulating plasma lipids are vital indicators for quantifying coronary artery disease (CAD) risk, yet traditional biomarkers like LDL, HDL, and triglycerides often exhibit limited predictive capacity. Advancements in lipidomics have identified novel molecular constituents with the potential to improve prognostication in CAD patients. However, the prognostic value of lipidomics for long-term mortality has not yet been investigated. Objective In our study, which was part of the European Collaborative Project on Inflammation and Vascular Wall Remodeling in Atherosclerosis (ATHEROREMO), we aimed to investigate the predictive value of specific molecular lipid species for long-term mortality. Methods We utilized data from the 581 CAD patients enrolled in the ATHEROREMO clinical imaging study, who were admitted for either diagnostic coronary angiography or percutaneous coronary intervention. We measured a series of serum lipid species, comprising ceramides (Cer) and cholesteryl esters (CE), by mass spectrometry-based shotgun lipidomics. Long-term all-cause mortality follow-up was conducted in 2022 via the Civil Registry. We used the Kaplan-Meier method and multivariable Cox-proportional hazards regression (correction for age, sex, cardiac risk factors, statin use, hypercholesterolemia, and angiography indication) to assess survival distributions and associations with all-cause mortality. Results Mean age was 61.5 years (IQR: 53.5-61.5), 75% were male. A total of 55% patients were diagnosed with acute coronary syndrome (ACS) and 45% with stable angina pectoris (SAP). During a median follow-up of 11 years (IQR: 10.1-13.4) 179 patients died. Five molecular lipid species (two cholesteryl esters, one ceramide and two ceramide ratios) correlated with mortality (see Table). As an example, Figure 1 demonstrates a clear survival difference between patients with Cer(d18:1/16:0)/Cer(d18:1/24:0) ratio below versus above the median. Findings were consistent for ACS and SAP. Conclusion Our study demonstrates the prognostic value of specific cholesteryl esters, ceramides and ceramide ratios for 11-year mortality in patients with CAD. To the best of our knowledge, this is the longest follow-up study so far within this domain.Table.Lipid molecule and Mortality 11-yFig.1 Kaplan Meier Ceramide ratio

Lipid availability influences ferroptosis sensitivity in cancer cells by regulating polyunsaturated fatty acid trafficking.

Ferroptosis is a form of cell death caused by lipid peroxidation that is emerging as a target for cancer therapy, highlighting the need to identify factors that govern ferroptosis susceptibility. Lipid peroxidation occurs primarily on phospholipids containing polyunsaturated fatty acids (PUFAs). Here, we show that even though extracellular lipid limitation reduces cellular PUFA levels, lipid-starved cancer cells are paradoxically more sensitive to ferroptosis. Using mass spectrometry-based lipidomics with stable isotope fatty acid labeling, we show that lipid limitation induces a fatty acid trafficking pathway in which PUFAs are liberated from triglycerides to synthesize highly unsaturated PUFAs such as arachidonic and adrenic acid. These PUFAs then accumulate in phospholipids, including ether phospholipids, to promote ferroptosis sensitivity. Therefore, PUFA levels within cancer cells do not necessarily correlate with ferroptosis susceptibility. Rather, how cancer cells respond to extracellular lipid levels by trafficking PUFAs into proper phospholipid pools contributes to their sensitivity to ferroptosis.

Alterations of Hepatic Lipidome Occur in a Gouty Model: A Shotgun Lipidomics Study.

Liver injury, such as nonalcoholic fatty liver disease, is a common symptom observed in patients with gout/hyperuricaemia. However, the exact mechanisms are still unclear. There is ongoing controversy about whether representative agents like colchicine and febuxostat, commonly used to manage gout, could also help prevent the liver injury. Liver plays a crucial role in uric acid (UA) production and lipid metabolism. Thus, the study aimed to investigate the aberrant lipid metabolism in the liver during injury and the effects of these drugs. An advanced multi-dimensional mass spectrometry-based shotgun lipidomics technology was employed for class-targeted lipid analysis of cellular lipidomes in hepatic tissue of a gouty model induced by a combination of monosodium urate crystals and high-fat diet with or without treatment with colchicine and febuxostat. Serum UA, blood urea nitrogen, creatinine, proinflammatory cytokines, expression of AMP-activated protein kinase protein, footpad histopathology, and footpad swelling and pain threshold of these mice were assessed to evaluate the progression of gout. Lipidomics analysis clearly demonstrated that the ectopic fat accumulation as well as changes in fatty acyls composition in TAG pool, impaired mitochondrial function resulted by decreased tetra 18:2 cardiolipin, and reduced 4-hydroxyalkenal bioavailability in liver tissue could contribute to liver damage to the gouty model. Treatment with colchicine or febuxostat not only ameliorated gouty symptoms but also corrected these abnormal hepatic lipid metabolism patterns. This study shed light on underlying mechanism(s) for liver injury in gout/hyperuricaemia and suggested that administration of drugs like colchicine and febuxostat could prevent liver injury.

Cold-induced phosphatidylethanolamine synthesis in liver and brown adipose tissue of mice

Increasing energy expenditure in brown adipose (BAT) tissue by cold-induced lipolysis is discussed as a potential strategy to counteract imbalanced lipid homeostasis caused through unhealthy lifestyle and cardiometabolic disease. Yet, it is largely unclear how liberated fatty acids (FA) are metabolized. We investigated the liver and BAT lipidome of mice housed for 1 week at thermoneutrality, 23 °C and 4 °C using quantitative mass spectrometry-based lipidomics. Housing at temperatures below thermoneutrality triggered the generation of phosphatidylethanolamine (PE) in both tissues. Particularly, the concentrations of PE containing polyunsaturated fatty acids (PUFA) in their acyl chains like PE 18:0_20:4 were increased at cold. Investigation of the plasma's FA profile using gas chromatography coupled to mass spectrometry revealed a negative correlation of PUFA with unsaturated PE in liver and BAT indicating a flux of FA from the circulation into these tissues. Beta-adrenergic stimulation elevated intracellular levels of PE 38:4 and PE 40:6 in beige wildtype adipocytes, but not in adipose triglyceride lipase (ATGL)-deficient cells. These results imply an induction of PE synthesis in liver, BAT and thermogenic adipocytes after activation of the beta-adrenergic signaling cascade.

Comparison of lipid profiles of male and female silkworm (Bombyx mori) pupae through high-resolution mass spectrometry-based lipidomics and chemometrics

Silkworm (Bombyx mori) pupae lipid profiles were analyzed using high-resolution mass spectrometry-based lipidomics. A total of 241 lipid molecular species were annotated with high confidence in male and female silkworm pupae. Triacylglycerol (TG), phosphoethanolamine (PE) and phosphocholine (PC) were the main lipid subclasses of silkworm pupae, accounting for 63, 41 and 38 lipid molecular species, respectively. No unique lipid molecular species were identified, but there were differences in the abundance of lipid molecular species between male and female silkworm pupae. Therefore, the differences in the lipid abundance of male and female silkworm pupae were analyzed by chemometrics. As a result, 8 lipid molecular species were screened for differential lipids. Hierarchical clustering analysis (HCA) showed that male and female silkworm pupae samples formed two distinct branches, indicating that these differential lipids could potentially be used as biomarkers to distinguish between male and female silkworm pupae.

Spinal cord injury disrupts plasma extracellular vesicles cargoes leading to neuroinflammation in the brain and neurological dysfunction in aged male mice

Aged individuals with spinal cord injury (SCI) are prevalent with increased mortality and worse outcomes. SCI can cause secondary brain neuroinflammation and neurodegeneration. However, the mechanisms contributing to SCI-induced brain dysfunction are poorly understood. Cell-to-cell signaling through extracellular vesicles (EVs) has emerged as a critical mediator of neuroinflammation, including at a distance through circulation. We have previously shown that SCI in young adult (YA) male mice leads to robust changes in plasma EV count and microRNAs (miRs) content. Here, our goal was to investigate the impact of old age on EVs and brain after SCI. At 24 h post-injury, there was no difference in particle count or size distribution between YA and aged mice. However, aged animals increased expression of EV marker CD63 with SCI. Using the Fireplex® miRs assay, Proteomics, and mass spectrometry-based Lipidomics, circulating EVs analysis identified distinct profiles of miRs, proteins, and lipid components in old and injury animals. In vitro, plasma EVs from aged SCI mice, at a lower concentration comparable to those of YA SCI mice, induced the secretion of pro-inflammatory cytokines and neuronal apoptosis. Systemic administration of plasma EVs from SCI animals was sufficient to impair general physical function and neurological function in intact animals, which is associated with pro-inflammatory changes in the brain. Furthermore, plasma EVs from young animals had rejuvenating effects on naïve aged mice. Collectively, these studies identify the critical changes in circulating EVs cargoes after SCI and in aged animals and support a potential EV-mediated mechanism for SCI-induced brain changes.

Exploration of the Lipid Profile of Edible Oleaginous Microgreens by Mass Spectrometry-Based Lipidomics.

The spreading awareness of the health benefits associated with the consumption of plant-based foods is fueling the market of innovative vegetable products, including microgreens, recognized as a promising source of bioactive compounds. To evaluate the potential of oleaginous plant microgreens as a source of bioactive fatty acids, gas chromatography-mass spectrometry was exploited to characterize the total fatty acid content of five microgreens, namely, chia, flax, soy, sunflower, and rapeseed (canola). Chia and flax microgreens appeared as interesting sources of α-linolenic acid (ALA), with total concentrations of 2.6 and 2.9 g/100 g of dried weight (DW), respectively. Based on these amounts, approximately 15% of the ALA daily intake recommended by the European Food Safety Authority can be provided by 100 g of the corresponding fresh products. Flow injection analysis with high-resolution Fourier transform single and tandem mass spectrometry enabled a semi-quantitative profiling of triacylglycerols (TGs) and sterol esters (SEs) in the examined microgreen crops, confirming their role as additional sources of fatty acids like ALA and linoleic acid (LA), along with glycerophospholipids. The highest amounts of TGs and SEs were observed in rapeseed and sunflower microgreens (ca. 50 and 4-5 μmol/g of DW, respectively), followed by flax (ca. 20 and 3 μmol/g DW). TG 54:9, 54:8, and 54:7 prevailed in the case of flax and chia, whereas TG 54:3, 54:4, and 54:5 were the most abundant TGs in the case of rapeseed. β-Sitosteryl linoleate and linolenate were generally prevailing in the SE profiles, although campesteryl oleate, linoleate, and linolenate exhibited a comparable amount in the case of rapeseed microgreens.

Untargeted lipidomics to identify characteristic signatures and mechanisms of mitochondrial diseases according to genetic origin

Background: The major challenge in mitochondrial diseases relies in their great heterogeneity, in terms of genetic origin (i.e. nuclear or mitochondrial), mutation diversity and clinical manifestations. The underlying mechanisms are still unclear and often considered common to most mitochondrial diseases. Hypothesis: According to the genetic origin, the different lipidomic profiles will reveal common as well as mutation-dependent signatures. Aims: i) Establish the characteristic signatures of human fibroblasts from mitochondrial diseases of distinct genetic origins: either nuclear: LRPPRC and MTFMT, or mitochondrial: NDUFS4, UQCRC2 and ECHS1 compared with healthy fibroblasts and, based on the established signatures, ii) identify the underlying mechanisms. Methods: We used a mass spectrometry-based untargeted lipidomics approach to scan for thousands lipid signals. Based on the identified signatures, selected players were evaluated by quantitative PCR. Results: Principal component analysis shows that each cell line differs from the others. Our lipidomics analyses show that few lipids were modulated in a similar way irrespective of the genetic origin, and especially the increase in cholesterol esters. In contrast, ganglioside metabolism was differentially changed according to the genetic origin. More specifically, while GM3 forms were mostly and significantly increased for MTFMT, UQCRC2 and ECHS1 and moderately increased for NDUFS4, GM3 were decreased for LRPPRC. In addition, the GA1 and GM2 forms produced from GM3 were reduced in all cell lines except for LRPPRC and NDUFS4 where their signals remained unchanged. Since the formation of GA1 and GM2 involves the B4GALNT1 enzyme, we measured its mRNA expression and observed a drastic decrease up to 90% for MTFMT, while it remained unchanged for LRPPRC. Conclusion: The use of untargeted lipidomics is a relevant and powerful approach for the identification of specific signatures and underlying mechanisms of mitochondrial disorders, illustrated here by differentially affected ganglioside metabolism according to genetic origin, providing a starting point that will ultimately guide towards nutritional and therapeutic alternatives. Montreal Heart Institute Fundation, Lactic Acidosis Association and FRQS. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Looking into the lipid profile of avocado and byproducts: Using lipidomics to explore value-added compounds.

Consumer priorities in healthy diets and lifestyle boosted the demand for nutritious and functional foods as well as plant-based ingredients. Avocado has become a food trend due to its nutritional and functional values, which in turn is increasing its consumption and production worldwide. Avocado edible portion has a high content of lipids, with the pulp and its oil being rich in monounsaturated fatty acids and essential omega-3 and omega-6 polyunsaturated fatty acids (PUFA). These fatty acids are mainly esterified in triacylglycerides, the major lipids in pulp, but also in minor components such as polar lipids (phospholipids and glycolipids). Polar lipids of avocado have been overlooked despite being recently highlighted with functional properties as well. The growth in the industry of avocado products is generating an increased amount of their byproducts, such as seed and peels (nonedible portions), still undervalued. The few studies on avocado byproducts pointed out that they also contain interesting lipids, with seeds particularly rich in polar lipids bearing PUFA, and thus can be reused as a source of add-value phytochemical. Mass spectrometry-based lipidomics approaches appear as an essential tool to unveil the complex lipid signature of avocado and its byproducts, contributing to the recognition of value-added lipids and opening new avenues for their use in novel biotechnological applications. The present review provides an up-to-date overview of the lipid signature from avocado pulp, peel, seed, and its oils.

Development of an advanced liquid chromatography–tandem mass spectrometry measurement system for simultaneous sphingolipid analysis

Mass spectrometry-based lipidomics approaches offer valuable tools for the detection and quantification of various lipid species, including sphingolipids. The present study aimed to develop a new method to simultaneously detect various sphingolipid species that applies to diverse biological samples. We developed and validated a measurement system by employing a single-column liquid chromatography-mass spectrometry system utilizing a normal-phase separation mode with positive ionization. The measurement system provided precision with a coefficient of variant below 20% for sphingolipids in all types of samples, and we observed good linearity in diluted serum samples. This system can measure the following sphingolipids: sphingosine 1-phosphate (S1P), sphingosine (Sph), dihydroS1P (dhS1P), dihydroSph (dhSph), ceramide 1-phosphate (Cer1P), hexosylceramide (HexCer), lactosylceramide (LacCer), dh-ceramide, deoxy-ceramide, deoxy-dh-ceramide, and sphingomyelin (SM). By measuring these sphingolipids in cell lysates where S1P lyase expression level was modulated, we could observe significant and dynamic modulations of sphingolipids in a comprehensive manner. Our newly established and validated measurement system can simultaneously measure many kinds of sphingolipids in biological samples. It holds great promise as a valuable tool for laboratory testing applications to detect overall modulations of sphingolipids, which have been proposed to be involved in pathogenesis processes in a series of elegant basic research studies.

Repeated cannabidiol treatment affects neuroplasticity and endocannabinoid signaling in the prefrontal cortex of the Flinders Sensitive Line (FSL) rat model of depression.

Delayed therapeutic responses and limited efficacy are the main challenges of existing antidepressant drugs, thereby incentivizing the search for new potential treatments. Cannabidiol (CBD), non-psychotomimetic component of cannabis, has shown promising antidepressant effects in different rodent models, but its mechanism of action remains unclear. Herein, we investigated the antidepressant-like effects of repeated CBD treatment on behavior, neuroplasticity markers and lipidomic profile in the prefrontal cortex (PFC) of Flinders Sensitive Line (FSL), a genetic animal model of depression, and their control counterparts Flinders Resistant Line (FRL) rats. Male FSL animals were treated with CBD (10 mg/kg; i.p.) or vehicle (7 days) followed by Open Field Test (OFT) and the Forced Swimming Test (FST). The PFC was analyzed by a) western blotting to assess markers of synaptic plasticity and cannabinoid signaling in synaptosome and cytosolic fractions; b) mass spectrometry-based lipidomics to investigate endocannabinoid levels (eCB). CBD attenuated the increased immobility observed in FSL, compared to FRL in FST, without changing the locomotor behavior in the OFT. In synaptosomes, CBD increased ERK1, mGluR5, and Synaptophysin, but failed to reverse the reduced CB1 and CB2 levels in FSL rats. In the cytosolic fraction, CBD increased ERK2 and decreased mGluR5 expression in FSL rats. Surprisingly, there were no significant changes in eCB levels in response to CBD treatment. These findings suggest that CBD effects in FSL animals are associated with changes in synaptic plasticity markers involving mGluR5, ERK1, ERK2, and synaptophysin signaling in the PFC, without increasing the levels of endocannabinoids in this brain region.

Diazobutanone-assisted isobaric labelling of phospholipids and sulfated glycolipids enables multiplexed quantitative lipidomics using tandem mass spectrometry.

Mass spectrometry-based quantitative lipidomics is an emerging field aiming to uncover the intricate relationships between lipidomes and disease development. However, quantifying lipidomes comprehensively in a high-throughput manner remains challenging owing to the diverse lipid structures. Here we propose a diazobutanone-assisted isobaric labelling strategy as a rapid and robust platform for multiplexed quantitative lipidomics across a broad range of lipid classes, including various phospholipids and glycolipids. The diazobutanone reagent is designed to conjugate with phosphodiester or sulfate groups, while accommodating various functional groups on different lipid classes, enabling subsequent isobaric labelling for high-throughput multiplexed quantitation. Our method demonstrates excellent performance in terms of labelling efficiency, detection sensitivity, quantitative accuracy and broad applicability to various biological samples. Finally, we performed a six-plex quantification analysis of lipid extracts from lean and obese mouse livers. In total, we identified and quantified 246 phospholipids in a high-throughput manner, revealing lipidomic changes that may be associated with obesity in mice.

The sphingosine 1-phosphate analogue, FTY720, modulates the lipidomic signature of the mouse hippocampus.

The small-molecule drug, FTY720 (fingolimod), is a synthetic sphingosine 1-phosphate (S1P) analogue currently used to treat relapsing-remitting multiple sclerosis in both adults and children. FTY720 can cross the blood-brain barrier (BBB) and, over time, accumulate in lipid-rich areas of the central nervous system (CNS) by incorporating into phospholipid membranes. FTY720 has been shown to enhance cell membrane fluidity, which can modulate the functions of glial cells and neuronal populations involved in regulating behaviour. Moreover, direct modulation of S1P receptor-mediated lipid signalling by FTY720 can impact homeostatic CNS physiology, including neurotransmitter release probability, the biophysical properties of synaptic membranes, ion channel and transmembrane receptor kinetics, and synaptic plasticity mechanisms. The aim of this study was to investigate how chronic FTY720 treatment alters the lipid composition of CNS tissue in adolescent mice at a key stage of brain maturation. We focused on the hippocampus, a brain region known to be important for learning, memory, and the processing of sensory and emotional stimuli. Using mass spectrometry-based lipidomics, we discovered that FTY720 increases the fatty acid chain length of hydroxy-phosphatidylcholine (PCOH) lipids in the mouse hippocampus. It also decreases PCOH monounsaturated fatty acids (MUFAs) and increases PCOH polyunsaturated fatty acids (PUFAs). A total of 99 lipid species were up-regulated in the mouse hippocampus following 3 weeks of oral FTY720 exposure, whereas only 3 lipid species were down-regulated. FTY720 also modulated anxiety-like behaviours in young mice but did not affect spatial learning or memory formation. Our study presents a comprehensive overview of the lipid classes and lipid species that are altered in the hippocampus following chronic FTY720 exposure and provides novel insight into cellular and molecular mechanisms that may underlie the therapeutic or adverse effects of FTY720 in the central nervous system.

Authentication of the species identity of squid rings using UHPLC-Q-Orbitrap MS/MS-based lipidome fingerprinting and chemoinformatics

Species mislabeling of commercial loliginidae squid can undermine important conservation efforts and prevent consumers from making informed decisions. A comprehensive lipidomic fingerprint of Uroteuthis singhalensis, Uroteuthis edulis, and Uroteuthis duvauceli rings was established using high-resolution mass spectrometry-based lipidomics and chemoinformatics analysis. The principal component analysis showed a clear separation of sample groups, with R2X and Q2 values of 0.97 and 0.85 for ESI+ and 0.96 and 0.86 for ESI-, indicating a good model fit. The optimized OPLS-DA and PLS-DA models could discriminate the species identity of validation samples with 100 % accuracy. A total of 67 and 90 lipid molecules were putatively identified as biomarkers in ESI+ and ESI-, respectively. Identified lipids, including PC(40:6), C14 sphingomyelin, PS(O-36:0), and PE(41:4), played an important role in species discrimination. For the first time, this study provides a detailed lipidomics profile of commercially important loliginidae squid and establishes a faster workflow for species authentication.

An altered plasma lipidome-phenome network characterizes heart failure with preserved ejection fraction.

Heart failure with preserved ejection fraction (HFpEF) is a multifactorial, multisystemic syndrome that involves alterations in lipid metabolism. This study aimed to test whether distinct plasma lipid profiles or lipid entities or both are associated with clinical and functional echocardiographic parameters in HFpEF. We examined the human plasma lipidome in HFpEF patients (n=18) with left ventricular ejection fraction ≥50% and N-terminal pro-brain natriuretic peptide (NT-proBNP) >125pg/mL and control subjects (n=12) using mass spectrometry-based shotgun lipidomics. The cohort included 8 women and 22 men with average age of 67.8±8.6 SD. The control and disease groups were not significantly different with respect to age, body mass index, systolic and diastolic blood pressure, and waist-to-hip ratio. The disease group experienced more fatigue (P<0.001), had more often coronary artery disease (P=0.04), and received more medications (beta-blockers, P<0.001). The disease group had significantly different levels of HFpEF-relevant parameters, including NT-proBNP (P<0.001), left ventricular mass index (P=0.005), left atrial volume index (P=0.001), and left ventricular filling index (P<0.001), and lower left ventricular end-diastolic diameter (P=0.014), with no difference in left ventricular ejection fraction. Significant differences in lipid profiles between HFpEF patients and controls could not be detected, including no significant differences in abundance of circulating lipids binned by carbon chain length or by double bonds, nor at the level of individual lipid species. However, there was a striking correlation between selected lipids with smoking status that was independent of disease status, as well as between specific lipids and hyperlipidaemia [with corresponding significance of either false discovery rate (FDR) <0.1 or FDR<0.01]. In an exploratory network analysis of correlations, we observed significantly stronger correlations within the HFpEF group between individual lipids from the cholesterol ester and phosphatidylcholine (PC) classes and clinical/echocardiographic parameters such as left atrial volume index, left ventricular end-diastolic diameters, and heart rate (FDR<0.1). In contrast, the control group showed significantly stronger negative correlations (FDR<0.1) between individual species from the PC and sphingomyelin classes and left ventricular mass index or systolic blood pressure. We did not find significant direct associations between plasma lipidomic parameters and HFpEF and therefore could not conclude that any specific lipids are biomarkers of HFpEF. The validation in larger cohort is needed to confidently conclude the absence of first-order associations.

Anti-platelet aggregation activities of different grades of Angelica sinensis and their therapeutic mechanisms in rats with blood deficiency: insights from metabolomics and lipidomics analyses.

In traditional Chinese medicine, the radix of Angelica sinensis (Oliv.) Diels (RAS) is mainly used to replenish and invigorate the blood circulation. This study investigated anti-platelet aggregation activities were used by New Zealand rabbits, and high-performance liquid chromatography data were obtained to determine the spectrum-effect relationship for different commercial grades of RAS. Plasma and urine metabolites were examined using ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry-based metabolomics to elucidate the mechanisms underlying the role of these metabolites in a rat model of blood deficiency (BD). Plasma and spleen metabolites were additionally examined using ultra-performance liquid chromatography plus Q-Exactive tandem mass spectrometry-based lipidomics to clarify the mechanisms of RAS in treating BD. The third grade of RAS exhibited the best activity in replenishing and invigorating blood in vitro and in vivo. Ferulic acid, ligustilide, senkyunolide I, uridine, and guanine are quality markers of anti-platelet aggregation activity. Based on the metabolomics results, 19 potential biomarkers were screened in plasma, and 12 potential metabolites were detected in urine. In lipidomics analyses, 73 potential biomarkers were screened in plasma, and 112 potential biomarkers were screened in the spleen. RAS may restore lipid metabolism by regulating disorders of glycerophospholipid and sphingolipid metabolism, the tricarboxylic acid cycle, amino acid metabolism (thereby improving energy metabolism), and arachidonic acid metabolism (thereby promoting blood circulation). These results provide a deeper understanding of the effects of different grades of RAS and a scientific reference for the establishment of grading standards and for the clinical use of RAS.

Quantifying yeast lipidomics by high-performance thin-layer chromatography (HPTLC) and comparison to mass spectrometry-based shotgun lipidomics.

Lipidomic analysis in diverse biological settings has become a frequent tool to increase our understanding of the processes of life. Cellular lipids play important roles not only as being the main components of cellular membranes, but also in the regulation of cell homeostasis as lipid signaling molecules. Yeast has been harnessed for biomedical research based on its good conservation of genetics and fundamental cell organisation principles and molecular pathways. Further application in so-called humanised yeast models have been developed which take advantage of yeast as providing the basics of a living cell with full control over heterologous expression. Here we present evidence that high-performance thin-layer chromatography (HPTLC) represents an effective alternative to replace cost intensive mass spectrometry-based lipidomic analyses. We provide statistical comparison of identical samples by both methods, which support the use of HPTLC for quantitative analysis of the main yeast lipid classes.

Lipidome analyses reveal radiation induced remodeling of glycerophospholipid unsaturation in lung tumor.

Radiotherapy is a pivotal treatment for lung cancer, significantly impacting tumor control and patient quality of life. Despite its benefits, the molecular mechanisms underlying radiotherapy-induced biological alterations in lung cancer cells remain inadequately understood. In this study, we employed a mass spectrometry-based lipidomics approach to investigate lipid profile changes in a lung cancer mouse model post-radiation. Lewis lung carcinoma (LLC) cells were injected into C57BL/6J mice, followed by radiation treatment with varying split doses. Our results showed an increase in sterol lipids and a decrease in glycerolipids, specifically triacylglycerides, indicating disrupted lipid storage. Additionally, we observed significant changes in glycerophospholipid unsaturation, suggesting a remodeling of membrane properties that may influence cell survival. Linear regression analysis demonstrated a significant negative correlation between glycerophospholipid unsaturation index and tumor weight, indicating a potential role in radiation-induced tumor cell death. These findings provide new insights into the lipid metabolic pathways affected by radiotherapy and could inform the development of improved therapeutic strategies for lung cancer treatment.

Analysis and Quantification of the Mitochondrial-ER Lipidome.

Mitochondria are vital organelles essential for cellular functions, but their lipid composition and response to stressors are not fully understood. Recent advancements in lipidomics reveal insights into lipid functions, especially their roles in metabolic perturbations and diseases. Previous methods have focused on the protein composition of mitochondria and mitochondrial-associated membranes. The advantage of our technique is that it combines organelle isolation with targeted lipidomics, offering new insights into the composition and dynamics of these organelles in pathological conditions. We developed a mitochondria isolation protocol for L6 myotubes, enabling lipidomics analysis of specific organelles without interference from other cellular compartments. This approach offers a unique opportunity to dissect lipid dynamics within mitochondria and their associated ER compartments under cellular stress. Key features • Analysis and quantification of lipids in mitochondria-ER fraction through liquid chromatography-tandem mass spectrometry-based lipidomics (LC-MS/MS lipidomics). • LC-MS/MS lipidomics provide precise and unbiased information on the lipid composition in in vitro systems. • LC-MS/MS lipidomics facilitates the identification of lipid signatures in mammalian cells.