Elaine Holmes

Background: Epidemiological evidence shows that fruit and vegetable (FV) intake reduces cardiovascular risk. Comparative effects of diets with different FV types on cardiometabolic disease risk markers remain unclear.

Objectives: This study aimed to compare the effects of standardised diets differing in FV types on vascular function, other cardiometabolic disease risk markers, urinary and plasma biomarkers in free-living adults with untreated prehypertension.

Methods: In a 9-wk randomised, controlled, crossover trial at 2 centres, 39 adults consumed standardised, provided diets with either 8 daily portions of common FV (apple, banana, pear, bell pepper, carrot, tomato), 8 daily portions of citrus and cruciferous FV, or 2 daily portions (low FV diet, control) for 2 wk per arm, with a 1-wk washout. Adherence was assessed using 24-h urinary potassium, sodium, and targeted plasma carotenoids and metabolites. The primary outcome was office blood pressure; secondary outcomes included pulse wave velocity (pwv), augmentation index standardised at 75 beats per minute (AIX75), lipids, and C-reactive protein (CRP). Between-group differences were assessed using linear mixed models with diet and period as fixed effects, and participant as random effect.

Results: Thirty-six participants completed the study (67% male, mean age 54±6 y; systolic BP 131.7±9.0 mmHg, total cholesterol: 5.4±1.1 mmol/L). No between-group differences were observed in office BP, PWV, AIX75, or CRP. Both common and citrus fruits and cruciferous FV diets tended to increase 24-h urinary potassium (by 6.94 mmol/24-h, P≤0.1; 8.0 mmol/24-h, P≤0.06, respectively), while 24-h urinary sodium remained comparable across diets (P≥0.87). Common FV diet significantly increased α- and β-carotene, and lycopene (P≤6.3x10-4), whereas citrus fruits and cruciferous FV increased lutein/zeaxanthin, β-cryptoxanthin, proline betaine, N-methylproline, and S-methyl-L-cysteine sulfoxide (P≤6.9x10-8). Common FV diet reduced total (-0.19 mmol/L, 95% confidence interval (CI): -0.32,-0.05), LDL (-0.15 mmol/L, 95% CI: -0.26,-0.03), and HDL (-0.05 mmol/L, 95% CI: -0.09,-0.00) cholesterol, whereas citrus and cruciferous FV reduced urinary creatinine (-1.19 mmol/24-h, 95% CI: -2.27,-0.11). No effects were observed on weight and physical activity.

Conclusions: Objective biomarkers confirmed FV adherence and suggest that FV types differentially modulate lipid and metabolic responses within 2 wk, without measurable vascular effects.

Paediatric burn injuries are a global health concern with long-term health consequences, such as psychological, immune, and cardiovascular complications, that can persist even after non-severe injuries. Emerging evidence suggests that biological sex may influence post-burn outcomes in children, as female burn survivors have been shown to experience higher mortality, scarring, anxiety, depression, and poorer quality of life compared to males. This study addresses a critical research gap by examining sex-specific lipidomic and inflammatory responses following paediatric non-severe burn injury. Children under five years were recruited as a part of the Childhood Burn Injury Biobank at hospital admission, with longitudinal follow-ups, and non-burn controls aged 1 and 3 were collected from the ORIGINS cohort. Plasma lipid profiling and acute-phase glycoprotein systemic inflammatory markers (GlycA and GlycB) were quantified using metabolic phenotyping with hair cortisol provided as a longitudinal measure of stress. Lipidomic analysis revealed acute-phase disruptions in fatty acids and lysophospholipids in both sexes but only females demonstrated a persistent increase of arachidonic acid (FA 20:4) and depletion of monoacylglycerols more than a year post-injury. Females also had significantly higher acute-phase GlycA/GlycB levels around the time of injury and exhibited increasing variability in hair cortisol over time, while male burn survivors did not. These findings highlight a sex-specific response between lipid metabolism, systemic inflammation and stress in paediatric recovery from non-severe burns. Understanding these differences may guide the development of targeted psychological and physiological strategies to improve long-term outcomes for young burn survivors.

Introduction
The biomarkers and the mechanisms underlying the cognitive decline in ageing are not fully clarified although they might be effective for dementia prevention. We comprehensively explore metabolites associated with cognitive function by conducting metabolomics analysis in a cohort study of general Japanese men.

Methods
The study population was 672 Japanese men aged 46-83 years without stroke, who were randomly selected for the SESSA study from Kusatsu City, Japan. Metabolomics using liquid chromatography mass spectrometry (LC-MS) was conducted on plasma samples, focusing on lipid metabolism. The 442 metabolites were identified. The cognitive function was assessed by Cognitive Abilities Screening Instrument (CASI), and CASI score less than 82 was defined as having mild cognitive impairment (MCI). We examined the metabolites among groups with and without MCI using principal component analysis and partial least squares regression (PLS) or PLS rank order of groups. Multivariable adjusted logistic regression estimated the odds ratios (ORs) and 95%CI of MCI for the extracted metabolites per standard deviation. The 9 domain specific MCI using median value of each domain specific CASI score as cutoff points were also examined. KEGG pathway analysis was done to clarify the linked pathway for the extracted metabolites.

Results
The prevalence of MCI was 5.5%. The 22 metabolites were statistically significantly associated with CASI score (q <0.05 in PLS, 21 metabolites in the positive direction and 1 metabolite in the negative direction). Phosphatidylcholines (PC) and Lysophosphatidylcholines (LPC) were associated with low risk of MCI (OR(95%CI): PC16:0/20:3; 0.51(0.32-0.51), LPC18:2/0.0; 0.59 (0.36-0.96), LPC20:3/0.0; 0.48(0.28-0.82)), phenacetylcarnitine was associated with the high risk of MCI (OR (95%CI); 1.33 (1.01-1.75)) (q <0.05). The analysis for domain specific MCI extracted the metabolites for short term memory, language abilities and category fluency. The Linoleic acid metabolism pathway was statistically significantly associated with CASI score.

Conclusion
Glycerophosphocolines such as PC16:0/20:3, LPC18:2/0.0 and LPC20:3/0.0 were reduced in participants with MCI, and those metabolites associated with low risk of MCI. Linoleic acid metabolism might be important for prevention of dementia among Japanese.

Methoxyacetic acid (MAA) is a testicular toxin that targets spermatocytes and round spermatids by disrupting mitochondrial function, leading to cellular energy depletion. Male Sprague-Dawley rats were given single oral doses of MAA (150 or 650 mg/kg), resulting in no mortality but transient toxicity signs and modest body weight effects, especially at the higher dose. Histopathology revealed dose- and time-dependent testicular damage, with selective germ cell necrosis by 48 h and extensive germ cell loss, spermatic giant cells, and epididymal inflammation observed in high-dose animals by 168 h. Metabolic analysis using high resolution 1H NMR spectroscopy and OPLS-DA identified elevated urinary excretion of N-butyryl glycine, a marker of mitochondrial dysfunction and impaired β-oxidation. The persistence of N-butyryl glycine and altered energy metabolites up to 168 h indicates sustained mitochondrial stress and disruption of ATP-dependent processes essential for spermatogenesis. Moreover, the close structural similarity between MAA and butyrate raises the possibility that MAA interacts directly with enzymes involved in butyryl-CoA turnover during the terminal steps of β-oxidation in rodents.

The Consortium for Metabonomic Toxicology (COMET) studies was designed to model metabolic responses to organ-and mechanism-specific toxins to predict acute drug toxicity in rats. A range of clinical chemical parameters were measured in 7-day toxicology studies for 86 toxins eliciting a range of organ-and mechanism-specific effects. Additionally, 21 surgical or physiological stressors were evaluated to identify physiological or metabolic responses that might confound the interpretation of observed toxicity profiles. From these studies on a total of 3473 rats measured at six pharmaceutical companies, we provide a set of 12 serum and 5 urine physical and clinical chemistry parameters. Samples were collected at 24 h, 48 h and 168 h post-dose for each animal and are presented as a downloadable database file. We also summarise the main observations based on the group response at the level of the individual toxin. We demonstrate that correlations between parameters, such as serum bilirubin and aspartate aminotransferase (AST), provide a more nuanced profile of organ-specific toxicity than consideration of individual parameters alone. In addition, we highlight the variability in the measured parameters across the dataset attributable to inter-laboratory differences, and the heterogeneity of metabolic responses to particular compounds or differences in temporal patterns of response. This clinical chemistry atlas of toxicity serves as a valuable reference tool for evaluating the potential toxicity of novel drug candidates.

The nutritional benefits of Extra Virgin Olive Oils (EVOOs) depend on their chemical composition. Currently, there is no simple way to compare the health benefits of different EVOOs. Samples from Australia, Greece, Italy, Spain and Tunisia (N = 423) were analyzed using proton nuclear magnetic resonance spectroscopy to screen against six quality parameters (free acidity, peroxides, K270, K232, Delta K, wax) and measure fat compositions. These fat compositions were compared against healthy eating guidelines to produce five binary descriptors, which were weighted by evidence to create an accessible Nutritional Quality Index (NQI). EVOOs were differentiated by saturated fat and balance between monounsaturated (MUFA) and polyunsaturated fat (PUFA). Most samples (56.4 %) showed poor SFA, poor PUFA and good MUFA (NQI = 56), 21 % had good SFA, poor PUFA and good MUFA (NQI = 81), and 19.4 % exhibited poor SFA, good PUFA and poor MUFA (NQI = 64). The NQI identifies EVOOs with superior nutritional value, enabling informed consumer choices.

Dried blood spot (DBS) sample collections can offer a minimally invasive, cost-effective alternative to traditional venepuncture for remote sampling and high-frequency metabolic profiling. We present an optimised protocol for DBS-based extraction and comprehensive untargeted 4D lipid profiling using ultrahigh-performance liquid chromatography coupled with high-resolution mass spectrometry, designed to support large-scale applications in population-wide lipidomics research. Inclusion of stable isotopically labelled internal standards allowed for semi-quantitative subclass-level correction for 10 μL DBS samples, enhancing the number of reproducible lipids within our curated target list (focussed on 432 unique rule-based lipid annotations out of 6845 features) across positive and negative heated electrospray ionisation modes. The reproducibility of unique lipid features detected in replicate DBS (n = 6) was assessed on both peak areas (351 lipids < 25 % CV) and calculated concentrations relative to internal standards (432 lipids < 25 % CV), underscoring the benefit of internal standard addition. Storage conditions for DBS were also evaluated to determine short-term lipid stability at different temperatures (-20 ˚C, 4 ˚C, room temperature, and 45 ˚C). The majority of lipid subclasses, excluding a minority of glycerophospholipids and oxylipins, were stable up to 1 week at -20 ˚C and 4 ˚C (log2-fold change < 30 % difference), which supports the short-term storage capacity for DBS in field and clinical settings. Similar stability was observed within a week at room temperature, excluding phosphatidylethanolamines and phosphatidylglycerols (log2-fold change > 30 % difference). Application of the optimised workflow to a microsampling device (n = 6) identified 432 lipid features (CV < 25 %) with three repeated samplings over an hour showing minimal impact on lipid profiles by principal component analysis, showing promise for high-frequency, longitudinal DBS monitoring in population health. This work represents a significant advance, highlighting the potential for reliable lipid analysis from DBS samples with short-term stability under various storage conditions, an important logistical benefit for remote or resource-limited settings.
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•Dried blood spots enable minimally invasive, cost-effective sampling in lipidomics•The developed untargeted 4D-lipidomic method annotates 432 lipids in 10 μL DBS•Majority of lipid subclasses are stable on DBS up to 1 week, ideal at -20°C and 4°C•Commercial microsampling devices suit remote, high-frequency lipid profiling

Pooled quality control (PQC) samples are the gold standard for data quality monitoring in metabolic phenotyping studies. Typically composed of equal parts from all study samples, PQCs can be challenging to generate in large cohorts or when sample volumes are low. As an alternative, externally sourced matrix-matched surrogate QCs (sQC) have been proposed. This study evaluates the performance of sQCs against PQCs for assessing analytical variation, data pre-processing, and downstream data analysis in a targeted lipidomics workflow.
Plasma samples (n = 701) from the Microbiome Understanding in Maternity Study, along with PQC (n = 80) and sQC (n = 80) samples, were analyzed using a lipidomics assay targeting 1162 lipids. QC samples were injected throughout acquisition, and data pre-processing was performed using each strategy. For simplicity, a subset (n = 381) of the study samples was used to assess differences in downstream statistical analyses.
Both QC approaches demonstrated high analytical repeatability. While PQC and sQC compositions differed, use of PQCs retained less than 4 % more lipid species during pre-processing. Univariate analysis identified more statistically significant lipids with PQC-based pre-processing, but multivariate model performance was similar between datasets.
This study provides a comprehensive comparison of QC strategies and emphasizes the importance of careful QC workflow selection. While PQCs offer advantages, sQCs serve as a suitable alternative for quality assessment and pre-processing. Their commercial availability also supports use as intra- and inter-laboratory long-term references, aiding data harmonization across studies and laboratories.
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•Comparison of two quality control workflows; pooled study and surrogate QC samples.•In-depth assessment of lipid composition, precision, and filtering.•OPLS-DA model predictive power maintained with both QC pre-processing strategies.•Surrogate QC samples are a robust alternative to a pooled QC in targeted lipidomics.