Mass Spectrometry Research Articles

Analysis of the senescence-associated cell surfaceome reveals potential senotherapeutic targets.

The accumulation of senescent cells is thought to play a crucial role in aging-associated physiological decline and the pathogenesis of various age-related pathologies. Targeting senescence-associated cell surface molecules through immunotherapy emerges as a promising avenue for the selective removal of these cells. Despite its potential, a thorough characterization of senescence-specific surface proteins remains to be achieved. Our study addresses this gap by conducting an extensive analysis of the cell surface proteome, or "surfaceome", in senescent cells, spanning various senescence induction regimes and encompassing both murine and human cell types. Utilizing quantitative mass spectrometry, we investigated enriched cell surface proteins across eight distinct models of senescence. Our results uncover significant changes in surfaceome expression profiles during senescence, highlighting extensive modifications in cell mechanics and extracellular matrix remodeling. Our research also reveals substantive heterogeneity of senescence, predominantly influenced by cell type and senescence inducer. A key discovery of our study is the identification of four unique cell surface proteins with extracellular epitopes. These proteins are expressed in senescent cells, absent or present at low levels in their proliferating counterparts, and notably upregulated in tissues from aged mice and an Alzheimer's disease mouse model. These proteins stand out as promising candidates for senotherapeutic targeting, offering potential pathways for the detection and strategic targeting of senescent cell populations in aging and age-related diseases.

Sustainable application of modified Luffa cylindrica biomass for removal of trimethoprim in water by adsorption with process optimization.

The present study describes a set of methodological procedures (seldom applied together), including (i) development of an alternative adsorbent derived from abundant low-cost plant biomass; (ii) use of simple low-cost biomass modification techniques based on physical processing and chemical activation; (iii) design of experiments (DoE) applied to optimize the removal of a pharmaceutical contaminant from water; (iv) at environmentally relevant concentrations, (v) that due to initial low concentrations required determination by ultra-performance liquid phase chromatography coupled to mass spectrometry (UPLC-MS/MS). A central composite rotational design (CCRD) was employed to investigate the performance of vegetable sponge biomass (Luffa cylindrica), physically processed (crushing and sieving) and chemically activated with phosphoric acid, in the adsorption of the antibiotic trimethoprim (TMP) from water. The optimized model identified pH as the most significant variable, with maximum drug removal (91.1 ± 5.7%) achieved at pH 7.5, a temperature of 22.5°C, and an adsorbent/adsorbate ratio of 18.6mgµg-1. The adsorption mechanisms and surface properties of the adsorbent were examined through characterization techniques such as scanning electron microscopy (SEM), point of zero charge (pHpzc) measurement, thermogravimetric analysis (TGA), specific surface area, and Fourier-transform infrared spectroscopy (FTIR). The best kinetic fit was obtained by the Avrami fractional-order model. The hypothesis of a hybrid behavior of the adsorbent was suggested by the equilibrium results presented by the Langmuir and Freundlich models and reinforced by the Redlich-Peterson model, which achieved the best fit (R2 = 0.982). The thermodynamic study indicated an exothermic, spontaneous, and favorable process. The maximum adsorption capacity of the material was 2.32 × 102µgg-1 at an equilibrium time of 120min. Finally, a sustainable and promising adsorbent for the polishing of aqueous matrices contaminated by contaminants of emerging concern (CECs) at environmentally relevant concentrations is available for future investigations.

Synthesis, Chemical Characterization, and Biological Evaluation of Hydrophilic Gold(I) and Silver(I) N-Heterocyclic Carbenes as Potential Anticancer Agents.

A series of new gold(I) and silver(I) N-heterocyclic carbenes bearing a 1-thio-β-d-glucose tetraacetate moiety was synthesized and chemically characterized. The compounds' stability and solubility in physiological conditions were investigated employing a multitechnique approach. Interaction studies with biologically relevant proteins, such as superoxide dismutase (SOD) and human serum albumin (HSA), were conducted via UV-vis absorption spectroscopy and high-resolution ESI mass spectrometry. The biological activity of the compounds was evaluated in the A2780 and A2780R (cisplatin-resistant) ovarian cancer cell lines and the HSkMC (human skeletal muscle) healthy cell line. Inhibition studies of the selenoenzyme thioredoxin reductase (TrxR) were also carried out. The results highlighted that the gold complexes are more stable in aqueous environment and capable of interaction with SOD and HSA. Moreover, these carbenes strongly inhibited the TrxR activity. In contrast, the silver ones underwent structural alterations in the aqueous medium and showed greater antiproliferative activity.

Associations of multiple serum metals with the risk of metabolic Syndrome among the older population in China based on a community study: a mediation role of peripheral blood cells

Metal exposure has been reported to be associated with metabolic syndrome (MetS), however, the evidence remains inconclusive, particularly in elderly individuals. From May to July 2016, serum levels of 16 metals were measured using inductively coupled plasma mass spectrometry (ICP-MS) in 852 elderly individuals (≥65 years) residing in Wuhan, China. Biological detection and disease recognition were based on individual surveys conducted during health check-ups. Spearman’s rank correlation analysis was performed to identify the correlation among serum metals. The data were Ln-transformed to fit a normal distribution for further analyses. Linear and logistic regression were applied to explore the associations between metals and diseases. Restricted cubic spline (RCS) analysis was utilized to examine dose-response relationships. The Weighted Quantile Sum (WQS) score was applied to determine the empirical weights of each heavy metal in the context of their combined effect on metabolic diseases. The prevalence of MetS, hypertension, diabetes, and hyperlipidemia were 46.36%, 68.90%, 24.65%, and 21.60%, respectively. Serum metal mixture was positively associated with the prevalence of MetS (OR = 1.92, 95% CI: 1.30-2.82), hypertension (OR = 1.50, 95% CI: 1.01-2.23), and diabetes (OR = 2.18, 95% CI: 1.48-3.22). In single metal models, we found that serum zinc levels were associated with an increased risk of MetS, while rubidium had a protective effect against MetS. Interestingly, different metals had distinct effects on specific diseases in this study: lithium and barium were more likely to influence blood pressure, while selenium had a more significant effect on blood glucose. Lipids were more susceptible to the effects of zinc, selenium, and strontium. Platelet count (PLT) and lymphocyte count (LYM) mediated the association between selenium exposure and hyperlipidemia, while neutrophil count (NEU) mediated the relationship between serum rubidium exposure and MetS. Our findings offer valuable etiological insights into the relationship between serum heavy metals and the prevalence of MetS, suggesting that peripheral blood cells may play a mediating role in this association.

Excretion characteristics of main compounds of Yigong San in urine, feces, and bile of rats.

Yigong San (YGS) is a traditional Chinese medicine formula used for pediatric anorexia, chronic atrophic gastritis, and irritable bowel syndrome. In this study, the excretion of eight main compounds, including liquiritin; isoliquiritin; hesperidin;ginsenosides Rb1, Re, and Rg1; and atractylenolides I and II, in rat urine, feces, and bile, was investigated by ultra-high performance liquid chromatography-tandem mass spectrometry. The results showed that the cumulative excretion rates of the compounds in rat urine, feces, and bile were 0.018-1.15%, 0.024-19.89%, and 0.0025-0.72%, respectively. Among the eight compounds detected, liquiritin was the richest in urine, and ginsenosides Re and Rg1 and atractylenolide I were mainly found in feces and bile. In summary, the main components of YGS are excreted via multiple approaches. Liquiritin is mainly through urine, whereas isoliquiritin;hesperidin;ginsenosides Rb1, Re,and Rg1; and atractylenolides I and II are mainly through feces. The excretion of these compounds in bile is usually positively correlated with that in feces. This study lays a foundation for further pharmacological research and application of YGS.

Gas-Phase Structures of Fucosylated Oligosaccharides: Alkali Metal and Halogen Influences.

Fucosylated carbohydrate antigens play critical roles in physiology and pathology with function linked to their structural details. However, the separation and structural characterization of isomeric fucosylated epitopes remain challenging analytically. Here, we report for the first time the influence of alkali metal cations (Li+, Na+, K+, Rb+, and Cs+) and halogen anions (Cl-, Br-, and I-) on the gas-phase conformational landscapes of common fucosylated trisaccharides (Lewis A, X, and H types 1 and 2) and tetrasaccharides (Lewis B and Y) using trapped ion mobility spectrometry coupled to mass spectrometry and theoretical calculations. Inspection of the mobility profiles of individual standards showed a dependence on the number of mobility bands with the oligosaccharide and the alkali metal and halogen; collision cross sections are reported for all of the observed species. Results showed that trisaccharides (Lewis A, X, and H types 1 and 2) can be best mobility resolved in the positive mode using the [M + Li]+ molecular ion form (baseline resolution r ≈ 2.88 between Lewis X and A); tetrasaccharides can be best mobility resolved in the negative mode using the [M + I]- molecular ion form (baseline separation r ≈ 1.35 between Lewis B and Y). The correlation between the number of oligosaccharide conformers as a function of the molecular ion adduct was studied using density functional theory. Theoretical calculations revealed that smaller cations can form more stable structures based on the number of coordinations, while larger cations induced greater oligosaccharide reorganizations; candidate structures are proposed to better understand the gas-phase oligosaccharide rearrangement trends. Inspection of the candidate structures suggests that the interplay between ion size/charge density and molecular structure dictated the conformational preferences and, consequently, the number of mobility bands and the mobility separation across isomers. This work provides a fundamental understanding of the gas-phase structural dynamics of fucosylated oligosaccharides and their interaction with alkali metals and halogens.

Enhancement of W Nanoparticles Synthesis by Injecting H2 in a Magnetron Sputtering Gas Aggregation Cluster Source Operated in Ar

AbstractSynthesis of W nanoparticles by magnetron sputtering combined with gas aggregation operated in Ar suffers from a continuous decrease of the synthesis rate, ceasing in a finite time interval, in the range of minutes to tens of minutes. Experimentally, we noticed that adding small amounts of H2 to Ar (5–20%) increases the synthesis rate, which remains constant over time, at a value dependent on the amount of injected hydrogen. Mass spectrometry investigations revealed, in the hydrogen presence, a dominance of the ArH+ ions over the Ar+ ones, associated also with an increased number of W+ and WH+ species in plasma, sustaining a substantial increase in the nucleation rate.

Discovery and Heterologous Expression of Trilenodin, an Antimicrobial Lasso Peptide with a Unique Tri-isoleucine Motif.

Lasso peptides are an increasingly relevant class of peptide natural products with diverse biological activities, intriguing physical properties, and unique chemical structures. Most characterized lasso peptides have been from Actinobacteria and Proteobacteria, despite bioinformatic analyses suggesting that other bacterial taxa, particularly those from Firmicutes, are rich in biosynthetic gene clusters (BGCs) encoding lasso peptides. Herein, we report the bioinformatic identification of a lasso peptide BGC from Paenibacillus taiwanensis DSM18679 which we termed pats. We used a bioinformatics-guided isolation approach and high-resolution tandem mass spectrometry (HRMS/MS) to isolate and subsequently characterize a new lasso peptide produced from the pats BGC, which we named trilenodin, after the tri-isoleucine motif present in its primary sequence. This tri-isoleucine motif is unique among currently characterized lasso peptides. We confirmed the connection between the pats BGC and trilenodin production by establishing the first Bacillus subtilis 168-based heterologous expression system for expressing Firmicutes lasso peptides. We finally determined that trilenodin exhibits potent antimicrobial activity against B. subtilis and Klebsiella pneumoniae, making trilenodin the first characterized biologically active lasso peptide from Firmicutes. Collectively, we demonstrate that bacteria from Firmicutes can serve as high-potential sources of chemically and biologically diverse lasso peptides.

Crucial Parameters for Immunopeptidome Characterization: A Systematic Evaluation

Immunopeptidomics is the area of knowledge focused on the study of peptides assembled in the major histocompatibility complex (MHC), or human leukocyte antigen (HLA) in humans, which could activate the immune response via specific and selective T cell recognition. Advances in high-sensitivity mass spectrometry have enabled the detailed identification and quantification of the immunopeptidome, significantly impacting fields like oncology, infections, and autoimmune diseases. Current immunopeptidomics approaches primarily focus on workflows to identify immunopeptides from HLA molecules, requiring the isolation of the HLA from relevant cells or tissues. Common critical steps in these workflows, such as cell lysis, HLA immunoenrichment, and peptide isolation, significantly influence outcomes. A systematic evaluation of these steps led to the creation of an ‘Immunopeptidome Score’ to enhance the reproducibility and robustness of these workflows. This score, derived from LC-MS/MS datasets (ProteomeXchange identifier PXD038165), in combination with available information from public databases, aids in optimizing the immunopeptidome characterization process. The ‘Immunopeptidome Score’ has been applied in a systematic analysis of protein extraction, HLA immunoprecipitation, and peptide recovery yields across several tumor cell lines enabling the selection of peptides with optimal features and, therefore, the identification of potential biomarker and therapeutic targets.

Thonningianin A from Penthorum chinense Pursh as a targeted inhibitor of Alzheimer's disease-related β-amyloid and Tau proteins.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by complex pathogenesis mechanisms. Among these, β-amyloid plaques and hyperphosphorylated Tau protein tangles have been identified as significant contributors to neuronal damage. This study investigates thonningianin A (TA) from Penthorum chinense Pursh (PCP) as a potential inhibitor targeting these pivotal proteins in AD progression. The inhibitory potential of PCP and TA on Aβ fibrillization was initially investigated. Subsequently, ultra-high performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry and biolayer interferometry were employed to determine TA's affinity for both Aβ and Tau. The inhibitory effects of TA on the levels and cytotoxicity of AD-related proteins were then assessed. In 3xTg-AD mice, the therapeutic potential of TA was evaluated. Additionally, the molecular interactions between TA and either Aβ or Tau were explored using molecular docking. We found that PCP-total ethanol extract and TA significantly inhibited Aβ fibrillization. Additionally, TA demonstrated strong affinity to Aβ and Tau, reduced levels of amyloid precursor protein and Tau, and alleviated mitochondrial distress in PC-12 cells. In 3xTg-AD mice, TA improved cognition, reduced Aβ and Tau pathology, and strengthened neurons. Moreover, molecular analyses revealed efficient binding of TA to Aβ and Tau. In conclusion, TA, derived from PCP, shows significant neuroprotection against AD proteins, highlighting its potential as an anti-AD drug candidate.

From Organotypic Mouse Brain Slices to Human Alzheimer Plasma Biomarkers: A Focus on Microglia

Alzheimer’s disease is a severe neurodegenerative disorder, and the discovery of biomarkers is crucial for early diagnosis. While the analysis of biomarkers in cerebrospinal fluid is well accepted, there are currently no blood biomarkers available. Our research focuses on identifying novel plasma biomarkers for Alzheimer’s disease. To achieve this, we employed a technique that involves coupling human plasma to mouse organotypic brain slices via microcontact prints. After culturing for two weeks, we assessed Iba1-immunopositive microglia on these microcontact prints. We hypothesized that plasma from Alzheimer’s patients contains factors that affect microglial migration. Our data indicated that plasma from Alzheimer’s patients significantly inhibited the migration of round Iba1-immunoreactive microglia (13 ± 3, n = 24, p = 0.01) compared to healthy controls (50 ± 16, n = 23). Based on these findings, we selected the most promising plasma samples and conducted mass spectrometry using a differential approach, and we identified four potential biomarkers: mannose-binding protein C, macrophage receptor MARCO, complement factor H-related protein-3, and C-reactive protein. Our method represents a novel and innovative approach to translate research findings from mouse models to human applications.

Characterization of Recycled Base Oils for Lubricants Using Statistical Approaches on Orbitrap Mass Spectrometry Data

Characterization of Recycled Base Oils for Lubricants Using Statistical Approaches on Orbitrap Mass Spectrometry Data

Sewage and Organic Pollution Compounds in Nairobi River Urban Sediments Characterized by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS).

Nairobi River sediments from locations adjacent to the Kawangware and Kiambio slums were analyzed via Fourier transform ion cyclotron resonance mass spectrometry with atmospheric pressure photoionization (APPI-FT-ICR-MS). The data from these ultrahigh resolution, untargeted measurements provided new insights into the impacts of local anthropogenic activity, which included likely benzo- and dibenzothiophene pollution with a suspected petrogenic origin, and prominent surfactant-like compositions. Other features in the data included highly abundant tetra-oxygenated compounds, and oxygenated nitrogen compounds with sphingolipid interpretations. Most notably, several hydrocarbon and oxygenated compound classes in the sediment data featured intensity patterns consistent with steroid molecular formulas, including those associated with sewage contamination investigatory work. In support of this interpretation, standards of cholesterol, β-sitosterol, stigmasterol, coprostanol, cholestanol, and 5α-sitostanol were analyzed via APPI, to explore steroid ionization behavior. Generally, these analytes produced radical molecular ions ([M]•+), and water-loss pseudo molecular ion species ([M-H2O]•+ and [M+H-H2O]+), among various other less intense contributions. The absence of pseudo molecular protonated species ([M+H]+) was notable for these compounds, because these are often assumed to form with APPI. The standard measurements demonstrated how steroids can create the observed intensity patterns in FT-ICR-MS data, and hence these patterns have the potential to indicate sewage contamination in the analysis of other complex environmental samples. The steroid interpretation for the Kawangware and Kiambio data was further verified by subjecting the steroid standard radical molecular ions to collision-induced dissociation and comparing the detected fragments to those for the corresponding isolated ions from a Kawangware sediment sample.

Polyphenolic Content and Antimicrobial Effects of Plant Extracts as Adjuncts for Craft Herbal Beer Stabilization

Extracts from locally grown aromatic plants can enhance the geographical characteristics and microbial stability of craft beers, which are often not pasteurized or filtered. Here, the chemical and antimicrobial properties of aqueous extracts from leaves of Myrtus communis L., Pistacia lentiscus L., Artemisia arborescens L., and floral wastes of Crocus sativus L., all cultivated in Sardinia (Italy), were assessed. P. lentiscus extract had the highest polyphenol content (111.20 mg GAE/g), followed by M. communis (56.80 mg GAE/g), C. sativus (32.80 mg GAE/g), and A. arborescens (8.80 mg GAE/g). Notably, only the M. communis extract demonstrated significant inhibitory activity against pathogenic and spoilage microorganisms, with minimum inhibitory concentrations of 0.18, 0.71, and 1.42 mg GAE/mL against Staphylococcus aureus, Lactiplantibacillus plantarum, and Lacticaseibacillus casei, respectively. Additionally, it reduced the growth of Levilactobacillus brevis and Fructilactobacillus lindneri at concentrations of 0.35 and 0.71 mg GAE/mL, respectively. Based on its significant antimicrobial activity, the M. communis extract was further characterized using high-resolution mass spectrometry, revealing high abundances of nonprenylated phloroglucinols, flavonoid derivatives (myricetin), and quinic acids. Lastly, adding M. communis extract (2.84 mg GAE/mL) to commercial beer effectively prevented the growth of L. brevis and F. lindneri, showing its potential to avoid beer’s microbial spoilage.

Reanalysis of the Huygens GCMS dataset. I. High-resolution methane vertical profile in the atmosphere of Titan

More than 15 years after its landing on the surface of Titan, the data returned by the Huygens probe remain the only available in situ information on Titan’s lower atmosphere and its methane content. In this work, we present a reanalysis of the Huygens probe data obtained by the Gas Chromatograph Mass Spectrometer (GCMS) instrument on board Huygens. GCMS measured the atmospheric composition almost continuously during the Huygens probe descent by acquiring mass spectra between 145 km of altitude and Titan’s surface. We first focus on the recollection, reconstruction, and recalibration of the GCMS dataset to facilitate similar future work. We then reevaluate the methane vertical profile in Titan’s lower atmosphere by applying novel mass spectra data-treatment methods to this dataset. In addition to finding a slightly lower methane mixing ratio than those previously reported using GCMS measurements above the Huygens probe landing site, our work has revealed several kilometric to subkilometric-scale oscillations in the methane vertical profile below 30 km of altitude. We discuss several hypotheses that could explain these features, such as multiple layers of optically thin clouds or local convection cells, and strongly encourage the reanalysis of other Huygens datasets to further investigate these variations in the methane mixing ratio.

Measurement report: Characteristics of airborne black-carbon-containing particles during the 2021 summer COVID-19 lockdown in a typical Yangtze River Delta city, China

Abstract. Black-carbon-containing (BCc) particles are ubiquitous in ambient air, significantly contributing to particulate matter (PM) pollution. The unexpected outbreak of the COVID-19 pandemic in the summer of 2021 prompted a localized and prolonged lockdown in Yangzhou, situated in the Yangtze River Delta, China. This lockdown led to significant alteration of local anthropogenic emissions, while neighboring cities continued regular operations, providing a unique opportunity for the investigation of BCc particle characteristics influenced by varying emission conditions. Single-particle aerosol mass spectrometer (SPA-MS) analysis revealed a notable decrease in the proportion of freshly emitted BCc particles during the lockdown (LD) period. However, PM2.5 concentrations remained relatively unchanged, with an observed increase in the proportion of aged BCc particles during LD compared to the period before the lockdown (BLD). The study also underscores the significant role of regional transport in PM2.5 pollution during the campaign. Moreover, reactive trace gases (e.g., NOx, SO2, and volatile organic compounds – VOCs) could form thick coatings on pre-existing particles, likely via enhanced heterogeneous hydrolysis under high relative humidity (RH), resulting in significant BCc particle growth (∼ 600 nm), as well as PM2.5 concentration, during LD. Our study highlights that short-term, strict local emission controls may not effectively reduce PM pollution due to the complex production and transmission characteristics of BCc particles and the nonlinear responses of PM2.5 to its precursors. Achieving further effective PM2.5 reduction mandates a focus on nuanced control of BCc particles and necessitates a comprehensive and extensive approach with a regionally coordinated and balanced control strategy through joint regulation.

Walnut extract protects against hepatic inflammation and toxicity induced by a high‐fat diet

AbstractA high‐fat diet (HFD) is one of the main causes of obesity and metabolic diseases. The liver is particularly affected by HFD causing metabolic dysfunction associated with fatty liver disease. Therefore, different strategies are used to mitigate the negative effects of HFD. This study aimed to assess the protective effects of walnut extract against HFD‐induced toxicity in mice. The mice were fed HFD and walnut extract alone or in combination. The walnut extract was analyzed for composition using high‐performance liquid chromatography with a diode array detector (HPLC‐DAD) and ultra‐high‐performance liquid chromatography with mass spectrometry (UHPLC–MS/MS). Serum lipid profile; liver histology; hepatic antioxidants such as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH‐Px), lipid peroxidation (TBARS), and reduced glutathione (GSH); inflammatory markers like IL‐6 and TNF‐α; and phospholipids were determined. Results showed that phenolic acids, epicatechin, catechin, benzaldehyde, and juglone were the main constituents in the extract. The HFD group showed increased hepatic fat accumulation as evidenced by biochemical and histopathological examinations compared to the control animals. The HFD group mice also showed increased body and cardiac weights, modified lipid profiles, decreased antioxidant status, and increased levels of hepatic inflammatory markers. The weights of the body and heart, lipid profiles, antioxidant contents (CAT, SOD, GSH‐Px, TBARS, and GSH), and pro‐inflammatory cytokines (IL‐6 and TNF‐α) were all normalized by consuming walnut extract. Similarly, the HFD group had significantly high amounts of hepatic lipase, phospholipid, and lysophospholipid levels, which were improved by walnut extract. In conclusion, walnut extract has been shown to play a unique role in promoting the recovery of liver damage caused by a high‐fat diet.

Unveiling novel serum biomarkers in intrahepatic cholangiocarcinoma: a pilot proteomic exploration

Recent advancements in proteomics have shown promise in identifying biomarkers for various cancers. Our study is the first to compare the serum proteomes of intrahepatic cholangiocarcinoma (iCCA) with cirrhosis (CIR), primary sclerosing cholangitis (PSC), and hepatocellular carcinoma (HCC), aiming to identify a proteomic signature that can effectively distinguish among these conditions. Utilizing high-throughput mass spectrometry on serum samples, we identified 845 proteins, of which 646 were suitable for further analysis. Unique clustering patterns were observed among the five groups, with significant proteomic differences. Our key findings include: S100 calcium-binding protein A9 (S100A9) and haptoglobin (HP) were more abundant in iCCA, while intercellular adhesion molecule 2 (ICAM2) was higher in HCC. Serum amyloid A1 (SAA1) and A4 (SAA4) emerged as potential biomarkers, with SAA1 significantly different in the iCCA vs healthy controls (HC) comparison, and SAA4 in the HCC vs HC comparison. Elevated levels of vascular cell adhesion molecule 1 (VCAM-1) in HCC suggested its potential as a differentiation and diagnostic marker. Angiopoietin-1 receptor (TEK) also showed discriminatory and diagnostic potential in HCC. ELISA validation corroborated mass spectrometry findings. Our study underscores the potential of proteomic profiling in distinguishing iCCA from other liver conditions and highlights the need for further validation to establish robust diagnostic biomarkers.

Stage-Specific Plasma Metabolomic Profiles in Colorectal Cancer

Background/Objectives: The objective of this study was to investigate the metabolomic profiles of patients with colorectal cancer (CRC) across various stages of the disease. Methods: The plasma samples were obtained from 255 subjects, including patients with CRC in stages I-IV, polyps, and controls. We employed capillary electrophoresis time-of-flight mass spectrometry and liquid chromatography triple quadrupole mass spectrometry to analyze hydrophilic metabolites comprehensively. The data were randomly divided into two groups, and consistent differences observed in both groups were analyzed. Results: Acetylated polyamines, such as N1-acetylspermine and N1, N12-diacetylspermine, consistently showed elevated concentrations in stage IV compared to stages I-III. Non-acetylated polyamines, including spermine and spermidine, exhibited increasing trends from polyp to stage IV. Other metabolites, such as histidine and o-acetylcarnitine, showed decreasing trends across stages. While acetylated polyamines have been reported as CRC detection markers, our findings suggest that they also possess diagnostic potential for distinguishing stage IV from other stages. Conclusions: This study showed stage-specific changes in metabolic profiles, including polyamines, of colorectal cancer.

Comprehensive identification of polyphenolic metabolites in aspen knotwood by combination of 2D NMR and HPLC-HRMS.

European aspen (Populus tremula L.) knotwood contains large amounts of polyphenolic metabolites, mainly flavonoids, and can be considered as a promising industrial-scale source of valuable bioactive compounds. Valorization of knotwood extractives requires detailed information on their chemical composition and a relevant analytical methodology. This study proposes combined analytical strategy for non-targeted screening and identification of polyphenolic plant metabolites and is aimed at comprehensive characterization of knotwood extractives. Aspen knotwood acetone extract with determined antioxidant activity was an object of the study. Two-dimensional NMR spectroscopy with Structure Elucidator expert system was used for preliminary search of major components and specific structures. Liquid chromatography-high-resolution mass spectrometry (HPLC-HRMS) with data-dependent MS/MS spectra acquisition was used as a complementary technique providing molecular-level characterization and identification of the detected metabolites. Twenty-eight phenolic metabolites were found and identified. Among them, flavonoids, aromadendrin and naringenin, as well as their glycosylated derivatives (mainly O-glucosides) and methyl ethers, dominated. Taxifolin and its 7-O-glucoside were detected as minor components. Other detected compounds are represented by p-coumaric acid and its rutinoside and small amounts of glycosylated ferulic acid. Nineteen of the detected compounds were discovered in aspen knotwood for the first time. The results were confirmed by preparative isolation of individual compounds and NMR studies. The proposed analytical strategy based on 2D NMR and HPLC-HRMS can be considered a powerful tool in the analysis of plant extractives and allowed for the identification and semi-quantification of a large number of polyphenols in aspen knotwood.