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Natural deep eutectic solvent in situ formation-based extraction method coupled to high-performance anion-exchange chromatography with pulsed amperometric detection for multiclass carbohydrates in hot pot bases.

A novel method was developed for the simultaneous extraction of fourteen multiclass carbohydrates from high-fat foods via the in situ formation of deep eutectic adducts from analytes and acetate ions. Different natural deep eutectic solvents (NADESs) composed of fructose and organic acids were tested as extraction solvents. A model NADES formulated with sodium acetate and fructose was characterized using Fourier transform infrared (FTIR) spectroscopy and hydrogen nuclear magnetic resonance (1H-NMR) spectroscopy. The critical extraction parameters were systematically optimized using multi-response surface methodology (MRSM) with a central composite design (CCD). The extract was analyzed using high-performance anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD) using a sodium hydroxide-sodium acetate eluent, which did not require organic solvents. This approach exhibited good linearity over the concentration range of 0.02-10 mg L-1, with correlation coefficients (r) ranging from 0.9994 to 0.9999. The limits of detection and quantification were in the ranges of 0.06-0.42 mg kg-1 and 0.19-1.3 mg kg-1, respectively, which were significantly lower than those of liquid chromatography (LC). The protocol was successfully applied to the determination of fourteen carbohydrates in forty-five hotpot seasoning samples. The recoveries ranged from 86.3% to 104.1%, with relative standard deviations (RSDs) of 0.9-7.1%. By integrating multiple techniques, this strategy simplifies operations, shortens extraction time, and achieves baseline separation of three carbohydrate classes that exhibit poor resolution using a conventional LC method. This study describes an efficient procedure for the simultaneous determination of multiple trace-level carbohydrates in complex samples using HPAEC-PAD.

Journal Article

Multi-omics reveal microbial functional traits and antifungal metabolites associated with lower Pseudogymnoascus destructans loads in bat cave soils.

White-nose syndrome, caused by Pseudogymnoascus destructans (Pd), is a major fungal disease threatening hibernating bats. Cave soils can serve as environmental reservoirs for Pd, yet the microbial and biochemical mechanisms underlying naturally low Pd burdens in some cave environments remain poorly understood. Here, we integrated soil microbiome profiling, metagenomics, metabolomics, multi-omics network analysis, and in vitro validation to investigate the ecological and functional basis of differential Pd loads in hibernating bat caves in Northeast China. The three caves shared cold, humid, and weakly acidic microenvironments, but differed significantly in electrical conductivity, soil water content, nutrient availability, and extracellular enzyme activities. Soil microbial communities showed significant inter-cave variation in composition, diversity, and niche breadth, with stochastic processes contributing substantially to community assembly. Environmental variables, particularly pH and Pd load, were important predictors of microbial community structure. Functional analyses revealed that the low-Pd Gezi Cave was enriched in genes associated with organic carbon degradation, nitrogen input and retention, and secondary metabolism. Metabolomic profiling further identified cave-specific metabolite signatures, among which Biochanin A, 4-Hydroxybenzaldehyde, Vanillin, and Arachidonic acid were negatively correlated with Pd loads. Integrated pathway and network analyses showed that differential genes and metabolites jointly mapped to secondary metabolite biosynthesis, aminobenzoate degradation, and flavonoid degradation pathways, forming a microbe-metabolite-functional gene coupling network involving key taxa such as Rhodococcus, Pseudorhodoplanes, and Rhodoplanes. In vitro assays confirmed that 4-Hydroxybenzaldehyde, Coumarin, and Vanillin inhibited Pd growth. Structural equation modelling further indicated that environmental heterogeneity was associated with variation in Pd loads through microbial functional attributes and metabolite profiles. These findings suggest that naturally low-Pd cave soils are associated with coordinated environmental filtering, microbial functional specialization, and antifungal metabolite production, providing mechanistic insight into microbial and biochemical constraints on Pd persistence in cave reservoirs.

Animals

Spatially resolved multi-omics analysis of indigenous Bacillus-fortified high-temperature Daqu.

Layer-dependent patterns associated with indigenous Bacillus fortification on high-temperature Daqu remain unclear. Here, six indigenous functional Bacillus strains were combined to fortify Daqu at three inoculation levels (QH4, QH5, QH6), with non-fortified as the control (CK). Upper, middle, and lower shelf-layer samples were profiled by physicochemical measurements, volatilomics, organic acid analysis, untargeted metabolomics, 16S/ITS amplicon sequencing, and metagenomics. PERMANOVA showed significant effects of treatment, spatial layer, and their interaction on physicochemical, volatile, bacterial, and fungal profiles (P = 0.001). Among the three inoculation levels, QH5 showed the most balanced performance: QH5_M exhibited the highest observed mean peak temperature (63.3 °C; +4.5 °C relative to CK_M), and its group-mean temperature remained ≥ 60 °C for seven consecutive days. Multi-omics analyses indicated coordinated, non-linear, and layer-dependent differences associated with indigenous Bacillus fortification, with QH5_M showing the most pronounced combined thermal, pyrazine, substrate, microbial, and predicted functional profile. These findings indicate that moderate indigenous Bacillus fortification was associated with distinct layer-dependent thermal and flavor profiles and coordinated microbial, metabolic, and predicted functional differences.

Bacillus

Recent advances in Strongyloides screening, diagnostics, therapeutics, and management.

PURPOSE OF REVIEW: Strongyloidiasis affects an estimated 30-100 million people globally and can have life-threatening consequences in immunocompromised hosts, yet it remains underdiagnosed due to limited access and performance of available diagnostics. Novel assays and anthelmintics may reshape screening, diagnosis, treatment, and prevention for at-risk populations. RECENT FINDINGS: Advances in molecular diagnostics coupled with robust stool extraction methods have supplanted traditional parasitologic methods in settings where nucleic acid amplification is feasible. Transition from standard immunoglobulin G (IgG)-based immunoassays to the new IgG- and IgG4-based rapid diagnostic tests using recombinant Strongyloides stercoralis nematode immunodominant E antigen (NIE) and/or S. stercoralis immunoreactive antigen (SsIR) has facilitated serologic screening at the point of care. The World Health Organization now conditionally recommends community-wide ivermectin mass drug administration in highly endemic settings. Regarding new treatment options, moxidectin is noninferior to ivermectin with 93-94% cure rates and a longer half-life, while emodepside shows 80-90% predicted cure rates in early trials and offers a mechanistically distinct option. Understanding of immunosuppressed populations at risk for hyperinfection has expanded, prompting updated screening recommendations. SUMMARY: Serologic and molecular tools are improving screening and diagnosis, and moxidectin and emodepside may broaden treatment options, but data in severe disease and special populations remain limited. Priorities include harmonized screening algorithms and prospective studies in high-risk groups.

Humans

Chemical and sensory profiling of fermented, washed, and artificially flavored coffee beans: Insights into flavour quality, authenticity, and food safety implications.

This study establishes an integrated framework combining chemical profiling, sensory analysis, and molecular mechanism evaluation to compare flavour quality and authenticity among fermented, washed, and artificially flavored coffees. GC&#xa0;&#xd7;&#xa0;GC-TOF-MS and UHPLC-HRMS showed that fermented samples had markedly higher ester and aromatic alcohol levels (total esters 74.5&#xa0;&#xb1;&#xa0;7.8&#xa0;mg&#xa0;kg-1; phenylethanol 27.5&#xa0;&#xb1;&#xa0;3.2&#xa0;mg&#xa0;kg-1, p&#xa0;<&#xa0;0.01), enhancing fruity-floral notes. Washed coffees contained the highest organic acid concentrations (45.2&#xa0;&#xb1;&#xa0;3.8&#xa0;mg&#xa0;kg-1, p&#xa0;<&#xa0;0.01), supporting brightness and umami. Artificially flavored coffees exhibited elevated exogenous aromatics (vanillin 21.5&#xa0;&#xb1;&#xa0;3.1&#xa0;mg&#xa0;kg-1) but significantly fewer Maillard products (p&#xa0;<&#xa0;0.05) and reduced flavour retention (55% after 14 days). Molecular docking revealed higher theoretical binding affinities for naturally generated compounds, suggesting a potential molecular basis for their greater sensory persistence. The framework supports constructing coffee quality fingerprints and verifying flavour authenticity.

Flavoring Agents

Microbial diversity, functional activities, and safety risks in fermented tea: a comprehensive review.

Microbial fermented teas are gaining global popularity due to their unique sensory profiles and health benefits. The quality and safety of these products are governed by complex microbial ecosystems that orchestrate the biotransformation of tea leaf components. This review addresses a critical paradox in the field: the same microbial activities that generate desirable bioactive metabolites, such as theabrownins and organic acids, also create ecological niches for mycotoxigenic fungi, posing significant health risks from contaminants like ochratoxin A, citrinin, and aflatoxins. While extensive research has cataloged the microbial diversity in these systems, a comprehensive framework linking processing environments to microbial community assembly, functional outcomes, and quantifiable safety risks remains elusive. This review systematically bridges this gap by synthesizing current knowledge on the microbial consortia-dominated by Aspergillus, Penicillium, Bacillus, and Lactiplantibacillus species-that drive tea fermentation. We critically analyze their functional roles in enhancing flavor, bioactivity, and potential probiotic activity while simultaneously evaluating the mechanisms of mycotoxin production and accumulation. By integrating microbial ecology, biochemistry, and food safety, we propose a forward-looking perspective focused on transitioning the industry from traditional, spontaneous fermentation to modern, controlled biotechnological processes. This approach, centered on the use of defined starter cultures, predictive modeling, and active biocontrol strategies, provides a roadmap for ensuring the consistent quality and safety of fermented tea products, ultimately unlocking their full potential as high-quality functional foods.

Tea

Probiotic supplementation improves body composition, lipid profiles, and fatty acid metabolism in combat sports athletes during the weight reduction phase.

PURPOSE: Pre-competition weight control for combat sports athletes may alter body composition and fatty acid metabolism. Probiotics have shown potential to regulate overall metabolism; however, their specific effects on fatty acid metabolism during weight control in athletes remain unclear. METHODS: Thirty-two combat sports athletes participating in the 4-week weight reduction period were assigned to either the probiotic group (Group E) or the placebo group (Group C). Body composition, lipid profiles, and fatty acid metabolism were measured before and after the 4-week weight reduction phase. RESULTS: All the athletes experienced a decrease in body weight, body mass index (BMI), body fat percentage, and muscle mass following the 4-week weight loss intervention. Notably, a more significant reduction in body fat percentage (p&#x2009;<&#x2009;0.05) was observed, along with lower levels of triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C), specifically in Group E. Weight loss intervention resulted in increased levels of short-chain fatty acids (SCFAs), specifically acetic acid, propionic acid, and butyric acid. Notably, Group E exhibited higher mean values for SCFAs compared to Group C (p&#x2009;<&#x2009;0.05). Additionally, the serum levels of &#x3b3;-linolenic acid and 8,11,14-eicosatrienoic acid were significantly reduced in Group E (p&#x2009;<&#x2009;0.05). In contrast, the majority of free fatty acids (FFAs) showed significant increases, with greater magnitudes of change observed in Group C (p&#x2009;<&#x2009;0.05). CONCLUSION: Probiotic supplementation can improve body composition, enhance SCFAs levels, and decrease circulating FFAs in combat sports athletes, suggesting that probiotics may have a beneficial impact on pre-competition weight management. TRIAL REGISTRATION NUMBER: chiCTR2400079908 (Reg Date:2024-01-16).

Humans

Acetic acid-induced translational repression involves eIF2B body formation and Ded1 sequestration into stress granules in yeast.

Elucidating the physiological impact of acetic acid stress and the corresponding yeast responses is essential for advancing fundamental biology and improving industrial alcoholic fermentation. Despite numerous genome-wide studies, information on the effects of acetic acid stress on yeast translational regulation remains limited. We found that a sublethal concentration of acetic acid (35 mM, 0.2% v/v) causes translational repression, accompanied by the formation of eIF2B bodies and the phosphorylation of eIF2&#x3b1;, both of which are involved in the regulation of translation initiation. Acetic acid also caused the sequestration of Ded1, a DEAD-box RNA helicase crucial for translation initiation, into stress granules. Removal of acetic acid restored translational activity and the proper localization of eIF2B and Ded1, indicating the reversibility of acetic acid-induced translational repression. Furthermore, when yeast cells were pretreated with 0.05% acetic acid, translational repression under subsequent 0.2% acetic acid stress was attenuated in wild-type cells but not in hrk1&#x394; cells. This indicates that Hrk1, a Pma1 activator, is required to sufficiently enhance tolerance to acetic acid-induced translational repression. These findings provide novel insights into the physiological effects of acetic acid stress on translational activity and translation-related factors in yeast cells.

Saccharomyces cerevisiae

Boosting kynurenic acid in kombucha via substrate selection: metagenomic and biochemical insights.

Kombucha is gaining global popularity for its health benefits. This study explored the use of chestnut honey, a rich source of kynurenic acid (KYNA), to produce kombucha enriched with this metabolite. Five variants were prepared using different green/black tea blends and carbon sources: white sugar or acacia honey (controls) versus chestnut honey. Samples were analyzed for tryptophan metabolites, physicochemical properties, and microbial diversity. Komagataeibacter and Enterobacter were predominant bacterial genera in SCOBY. Candida and Aspergillus were predominated in the single sample analyzed for fungi. During fermentation, tryptophan decreased, while kynurenine increased. KYNA levels remained largely stable during fermentation and were mainly influenced by the fermentation substrate. No melatonin pathway derivatives were detected. On day 7, chestnut honey yielded kombucha with 381.680-739.915&#xa0;&#x3bc;mol/L KYNA and elevated myricetin. Overall, chestnut honey-based kombucha represents a system in which substrate composition appears to be the main factor influencing KYNA levels in the final beverage.

Kynurenic Acid

Reversed unidirectional transport in a Janus polyurethane/alginate dressing for directional postbiotic delivery to infected wounds.

Probiotic-derived postbiotics exhibit significant potential for infected wound control; however, their effective and localized delivery at wound sites remains a challenge. This study developed a polyurethane/alginate composite nonwoven via electrospinning to establish a postbiotic delivery platform for Bifidobacterium bifidum BD-1 (PU/Alg/BD-1). The beaded fibrous hydrophobic PU layer and hydrophilic Alg layer form a wettability gradient, enabling reversed unidirectional fluid transport toward the wound interface while inhibiting backflow. In vitro results showed that PU/Alg/BD-1 exhibited significant antibacterial activity against Staphylococcus aureus and Escherichia coli and good cytocompatibility with a hemolysis rate of <5%. Targeted metabolomic analysis revealed multiple organic acids in the BD-1 metabolites, which contributed to its antibacterial activity. In vivo microbial analysis verified that PU/Alg/BD-1 effectively reduced the relative abundance of Staphylococcus at the wound site while increasing the proportions of Corynebacterium and Psychrobacter. This microbial modulation contributed to infection control in a rat full-thickness infected wound model, accompanied by a shift in the macrophage phenotype and the downregulation of inflammatory factors including IL-6, TNF-&#x3b1;, and TGF-&#x3b2; in the PU/Alg/BD-1 group. Compared with the blank control, conventional gauze, PU/Alg, and BD-1 groups, PU/Alg/BD-1 significantly promoted wound contraction and re-epithelialization and enhanced collagen deposition. Hence, this study provides an effective material construction strategy for the application of probiotic-derived postbiotics to promote wound healing, demonstrates the potential of BD-1 to regulate the wound microenvironment and accelerate healing, and thereby offers a novel approach for the treatment of infected wounds.

Journal Article

Multi-omics insights into the physiological mechanisms of bile acid accumulation in the gallbladder in brumation-like snakes.

Hibernation/brumation represents an important physiological adaptation for animals to cope with seasonal environmental changes. Field observations suggested increased gallbladder weight in the Five-pacer viper (Deinagkistrodon acutus) during brumation, and our quantitative measurements confirmed this increase together with bile acid accumulation. By integrating a multi-omic approach, this study elucidates the regulatory mechanisms of bile acid accumulation in the gallbladder during brumation. Results showed that taurocholic acid (TCA) and taurodeoxycholic acid (TDCA) were the major components in the gallbladder of the brumation-like group, with significantly elevated concentrations of bile acids, whereas bile acid concentrations in serum and intestinal contents were markedly reduced, indicating suppression of the enterohepatic circulation and consequent accumulation of bile acids in the gallbladder. Hepatic transcriptomic analysis revealed significant downregulation of bile acid synthesis and regulatory genes in brumation-like snakes. In contrast, the alternative synthesis pathway gene sterol 27-hydroxylase (CYP27A1) and some transporter genes were slightly upregulated. Further, some modification genes and regulatory genes showed no significant differences between active and brumation-like states. Gut microbiota analysis demonstrated Akkermansia muciniphila, Bacteroides fragilis, and Citrobacter freundii were more enriched in the active group, which were common microbes related to bile acid metabolism, and the correlation analysis confirmed this relationship. Taken together, these findings indicate that the "physiological bile acid accumulation" observed in snakes during brumation-like state is jointly driven by suppressed hepatic synthesis, reduced enterohepatic circulation, and remodeled microbial community structure. The study provides novel comparative physiological insights into extreme metabolic homeostasis in animals.

Animals

Quantifying the aromatic amino acid metabolome: UPLC-MS/MS analysis of aromatic amino acids and their host and co-metabolites in plasma.

Aromatic amino acids (AAAs), tryptophan, phenylalanine, and tyrosine along with their pathway metabolites have been implicated in the pathogenesis of diseases ranging from cardiovascular, neurological, inflammatory, and cancer diseases, among others. As such, the measurement of the primary AAAs, their host pathway metabolites, and microbiome derived co-metabolites in blood can provide a sensitive reflection of systemic health. The aim of the study was to develop a method for the quantification of 17 metabolites, the three AAAs and various of their metabolites in plasma using a high-throughput ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. The method demonstrated a dynamic range (1 to 16,700&#xa0;ng/mL), with detection limits (LOD) as low as 0.05&#xa0;ng/mL. Quantification limits ranged from 3 to 5019&#xa0;ng/mL (LLOQ) and up to 16,700&#xa0;ng/mL (ULOQ). Recovery at LQC, MQC, and HQC was satisfactory and consistent across most metabolites, with significant matrix effects observed only for 4-ethylphenol sulfate. Furthermore, intra and inter-day accuracy and precision met all acceptance criteria at all quality control concentrations for most of the metabolites. Measurement of NIST SRM 1950 showcased the method's accuracy for most of the metabolites. Finally, the method was applied on the analysis of plasma samples from 55 individuals (13 males and 42 females) providing information on AAAs and their pathway metabolites relevant concentrations in human plasma.

Amino Acids, Aromatic

Causal Relationship of Polyunsaturated Fatty Acids With Mental Disorders: A Systematic Review and Meta-analysis.

CONTEXT: Mental disorders (MDs) pose a important global health challenge, with a complex pathogenesis complicating treatment development. Nutritional interventions, particularly polyunsaturated fatty acids (PUFAs), have gained attention as potential therapeutic options. OBJECTIVE: This Mendelian randomization (MR) meta-analysis aimed to evaluate the potential causal relationship between PUFAs and MDs. DATA SOURCES: Genome-wide association study data were utilized to analyze the association between PUFAs (including omega-3, omega-3 percentage [omega-3%], omega-6, omega-6 percentage [omega-6%], and omega-6 to omega-3 ratio) and 12 major MDs. DATA EXTRACTION: Two-sample MR technology was used to assess the role of PUFAs in MDs. DATA ANALYSIS: The MR analysis revealed that genetically predicted omega-3 was causally linked to MDs, such as obsessive-compulsive disorder, bipolar disorder, schizophrenia, and major depressive disorder. Omega-3% exhibited protective effects against emotional personality disorder. Conversely, omega-6 was inversely correlated with attention-deficit/hyperactivity disorder risk, while a high omega-6 to omega-3 ratio was associated with an increased risk of depression and other mood disorders. CONCLUSION: High omega-3 levels and omega-3% may reduce the risk of MDs, whereas a high omega-6:omega-3 ratio may elevate the risk. These findings highlight the potential of PUFAs, particularly omega-3, in MD prevention and treatment, while underscoring the need for further research into the complex interactions between omega-3 and omega-6. The study provides a scientific foundation for future clinical trials and dietary intervention strategies. SYSTEMATIC REVIEW REGISTRATION: PROSPERO no. CRD42024598472.

Humans

A prospective pharmacokinetic interaction study between rifampicin and fusidic acid for the treatment of staphylococcal infections.

OBJECTIVE: Fusidic acid with rifampicin is used for the treatment of severe staphylococcal infection, particularly prosthetic joint infections. Previous studies using twice daily fusidic acid showed rifampicin increases fusidic acid clearance, potentially causing sub-therapeutic concentrations. It is uncertain whether this occurs with three-times daily dosing. This study sought to re-evaluate this potential drug-drug interaction. METHODS: In this prospective, open-label drug-drug interaction population pharmacokinetic (PK) study, participants were randomized to receive fusidic acid or rifampicin for 24&#x2005;hours, followed by combination therapy for the duration of treatment. Drug concentration assays used liquid-chromatography mass spectroscopy on dried blood spots. Population PK models were built for fusidic acid, rifampicin and 25-desacetyl rifampicin. RESULTS: Ten participants were recruited. Inter-individual variability for both absorption (98.1%) and clearance (77.8%) were high for fusidic acid. A population pharmacokinetic model for fusidic acid revealed that early autoinhibition dominated over later rifampicin-mediated induction, resulting in a net decrease in fusidic acid clearance. The mean fusidic acid area under the curve during each dosing interval (AUC&#x3c4;) at steady state was 1.76-fold [0.049, 34.918] higher relative to Day 1, despite high uncertainty.Large inter-individual (110%) variability in absorption was observed for rifampicin. There was no apparent effect on rifampicin metabolism by fusidic acid co-administration, however, fusidic acid decreased clearance of 25-desacetyl rifampicin. CONCLUSION: In patients treated with fusidic acid three times daily in combination with rifampicin, autoinhibition potentially counteracted rifampicin induction such that fusidic acid concentrations were not reduced. Rifampicin clearance was not affected by fusidic acid, but 25-desacetyl rifampicin clearance was decreased. There was large inter-individual variability in the observed concentrations and final parameter estimates.

Fusidic Acid

Single-organ proteomics in Drosophila melanogaster larva.

The combination of genetic accessibility, organ complexity, evolutionary conservation, and cost-efficiency makes Drosophila melanogaster (Dm) a well-known model system for biomedical and fundamental biological research. Proteomic analysis of single organs enables the identification and quantification of proteins expressed in specific organs. This will help to uncover specific biological functions and unique protein profiles that are not detectable in whole-organism analyses. In this study we have isolated single organs form Dm larvae, and we have performed a deep proteomics mapping by following a minimal manipulation preparation procedure. The combined dataset across all organs comprised 9132 identified proteins. As anticipated, principal component analysis (PCA) revealed clear separation between the proteomes of most organs, confirming distinct protein profiles. These findings demonstrate the applicability of the sample preparation strategy for high-resolution proteomic characterization of individual organs in Drosophila. Given the extensive genetic tools available for this model organism, our approach has the potential to open new avenues for proteomic studies in Drosophila melanogaster and any other biological systems where the sample amount is limiting. SIGNIFICANCE STATEMENT: Drosophila melanogaster is a well-known model system for biomedical and fundamental biological research that serves as a valuable in vivo model organism due to its high degree of evolutionary conservation with higher vertebrates, tractable genetics, and logistical efficiency. However, the proteome of Drosophila at single organ level has been elusive to date, due to several factors like low sensitivity of previous generation mass spectrometers and sample preparation procedures, difficult isolation of some organs. In this study we have applied a compilation of advanced methods including minimal sample manipulation together with simple, straightforward and efficient protein extraction and digestion methods. Obtained peptides were minimally handled to be analyzed by applying specific and sensitive nLC methods coupled on-line to state-of-the-art MS/MS system. Altogether, the applied strategy allowed us to get the first single organ study to date for this animal. These datasets represent a significative resource for future genomic, transcriptomic and proteomic studies in Drosophila, as multi-omic integration requires deep proteomics to translate data into functional biochemistry, and serves as a critical bridge and an indispensable standalone resource across the genomic, transcriptomic, and proteomic landscapes.

Animals

Effect of a 6-month low-carbohydrate diet on the circulating fatty acid composition in patients with type 2 diabetes: a secondary analysis of an open-label randomized controlled trial.

BACKGROUND: Circulating fatty acid profiles are linked to cardiovascular disease risk and mortality. Short-term interventions suggest that low-carbohydrate diets (LCDs) promote cardioprotective shifts in circulating fatty acids in obesity. OBJECTIVES: We examined whether a 6-mo, non-calorie-restricted, LCD high in fat similarly improves circulating fatty acid composition in adults with type 2 diabetes. METHODS: In an open-label, randomized, controlled trial, 71 individuals with type 2 diabetes were randomly assigned 2:1 to an LCD [maximum of 20 E% (energy per cent) carbohydrates] or a control diet (50-60 E% carbohydrates) for 6 mo with no restriction in energy intake. The prespecified secondary outcomes were the mean difference in change between groups in serum phospholipid fatty acids in weight percentage (wt%) measured by gas chromatography and reported as 95% confidence intervals (CIs) and significance adjusted for multiple comparisons (q value). RESULTS: LCD reduced total saturated [-0.6 (CI: -0.9, -0.2)] and monounsaturated fatty acids [-0.9 (CI: -1.4, -0.3)] and increased total polyunsaturated fatty acids [1.3 (CI: 0.6, 2.0)] compared with the control diet (all q < 0.05). Importantly, LCD reduced palmitoleic acid (16:1n-7) [-0.13 (CI: -0.21, -0.06)], a marker of de novo lipogenesis, by 23% and dihomo-&#x3b3;-linolenic acid (20:3n-6) [-0.38 (CI: -0.67, -0.09)] by 12%, whereas it increased arachidonic acid (20:4n-6) [1.1 (CI: 0.3, 2.0)] by 9% compared with the control diet (all q < 0.05). Moreover, the LCD improved estimated desaturase activities by lowering stearoyl-coenzyme A desaturase 1 [-0.5 (CI: -0.7, -0.2)] and &#x394;6 desaturase [-0.6 (CI: -0.9, -0.2)] and increasing &#x394;5 desaturase [1.05 (CI: 0.3, 1.79)] activities, respectively (all q < 0.01). These changes occurred despite a 2.6-fold higher intake of saturated fatty acids in the LCD group. CONCLUSIONS: A 6-mo, non-calorie-restricted LCD modified the circulating composition of fatty acids in adults with type 2 diabetes in a manner consistent with a potentially favorable cardioprotective profile. This trial was registered at www. CLINICALTRIALS: gov as NCT03068078.

Humans

Blood Bile Acids for Inflammatory Bowel Disease Diagnosis and Disease Activity Assessment: A Metabolomics Meta-Analysis.

Alterations in circulating bile acids (BAs) have been reported in inflammatory bowel disease (IBD), but the consistency of these changes across clinically relevant comparisons remains unclear. Our goal was to investigate systemic BA alterations in IBD using a metabolomics meta-analysis with an exploratory analysis of BA-related gene expression as a supporting context. A systematic review and meta-analysis of 28 metabolomics studies examined blood BA profiles associated with IBD, IBD diagnosis, and disease activity assessment. Univariate analysis and logistic regression modeling of two independent IBD cohorts explored the blood BA-related genes and IBD. Across 28 studies that comprised 5056 IBD patients, 1721 healthy controls, and 314 non-IBD patients, 131 BAs were reported. Eight predefined clinical comparisons were eligible for the meta-analysis. Lower secondary BA levels were consistently observed in IBD patients compared with controls, between UC and CD, and in active versus remission patients. Deoxycholic acid, glycodeoxycholic acid, and taurodeoxycholic acid were frequently decreased, whereas glycocholic acid was increased in certain comparisons. Transcriptomics analyses revealed differential expression of several BA-related genes in blood, including SLC51A, ABCB4, and ACOT8, across the comparisons. Our findings identify consistent circulating BA alterations in IBD and highlight the relevance of blood BA for future biomarker research in the diagnosis and disease activity assessment.

Humans

Proteomic characterization of the acquired enamel pellicle under acidic challenges at early and mature formation stages.

OBJECTIVES: This study aimed to characterize acquired enamel pellicle (AEP) proteomic changes after exposure to citric acid (CA) and hydrochloric acid (HCl) under different pellicle formation times (3 and 120&#x202f;min) in the same volunteers. DESIGN: Nine healthy volunteers participated in this randomized crossover in vivo study. The AEP was allowed to form for 3 or 120&#x202f;min and subsequently exposed for 10&#x202f;s to deionized water (control), 1% CA (pH 2.5), or 0.01&#x202f;M HCl (pH 2.0). Pellicle samples were collected, followed by protein extraction, tryptic digestion, and analysis by nanoliquid chromatography (nanoLC) coupled to mass spectrometry (MS) with MSE (data-independent acquisition; nanoLC-MS&#x1d31;). Label-free quantitative proteomics were performed for relative quantification using t-test (p&#x202f;<&#x202f;0.05). RESULTS: At 120&#x202f;min, CA exposure markedly reduced several typical AEP proteins, especially acidic proline-rich proteins (PRPs). Conversely, basic PRPs were upregulated, suggesting acid-resistance protein signature. At 3&#x202f;min, basal-layer proteins (PRPs, cystatins, histatins and mucins) were more abundant. Hemoglobins increased 6-8-fold (up to 150-fold in 3&#x202f;min control), suggesting association with early pellicle formation and an acid-resistant protein signature. CA exposures for 120&#x202f;min also upregulated typical AEP proteins (PRPs, mucins, cystatins, immunoglobulins), while HCl exposure depleted albumins and lactotransferrin. CONCLUSION: Intrinsic and extrinsic acids induce distinct proteomic signatures in the AEP. Hemoglobin and PRPs appear consistently enriched in the early pellicle layer, reflecting an initial acid-resistant protein signature. These findings provide new insights into the molecular remodeling of the AEP following intrinsic and extrinsic acid exposure, highlighting proteins potentially involved in early-stage pellicle formation.

Humans