Search Results (10,217)

Background/Objectives: This study is the first to investigate the potential mechanism of star anise extract (SAE) in protecting against cold stress-aggravated acute lung injury (CSALI) in rats. Methods: A rat CSALI model was induced via combined lipopolysaccharide challenge and cold stress exposure. The preventive effects of SAE were evaluated using cytotoxicity assays, quantification of biochemical indices and inflammatory factors, and histopathological examination. Ultra-performance liquid chromatography coupled with high-resolution mass spectrometry (UPLC–HRMS)-based serum metabolomics was employed to systematically profile CSALI-associated metabolic alterations and decipher the potential mechanism underlying the preventive effects of SAE. Results: SAE alleviated pathological progression of CSALI, suppressed inflammatory cell migration, markedly reduced pulmonary inflammatory cell infiltration, and ameliorated lung tissue injury in CSALI rats. SAE also improved abnormal liver function indicators and lowered the levels of pro-inflammatory factors in both serum and bronchoalveolar lavage fluid (BALF). Serum metabolomics analysis identified and annotated 24 disease-altered differential metabolites and evaluated the protective effects of SAE on them. These metabolites were significantly enriched in two key metabolic pathways related to the pathogenesis of CSALI, including arachidonic acid metabolism and glycerophospholipid metabolism. Furthermore, based on metabolite changes, phospholipase A2 was hypothesized as a potential key regulatory factor that may cooperate with arachidonic metabolism to suppress the inflammatory cascade. Conclusions: These findings demonstrated that SAE exerted prominent anti-inflammatory activity and effectively protected against lung injury in CSALI rats. Full article

Hair is an easily obtainable, non-invasive biomatrix that allows for the assessment of long-term physiological responses to environmental and anthropogenic stressors in wildlife populations. Herein, an ultra-high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (UHPLC-ESI-MS/MS) method was validated to verify its suitability for the simultaneous determination of cortisol (CORT) and its metabolite, cortisone (CORN), in hair samples collected from wild-living grey wolves (Canis lupus). Hair samples were extracted with methanol and purified using solid-phase extraction on Strata-X cartridges, which enabled effective mitigation of matrix effects. Data for the glucocorticoids were normalized using internal standards. The method demonstrated good linearity for the target stress hormones, with satisfactory precision (RSD < 15%) and limits of quantification of 4.13 pg/mg for CORT and 2.49 pg/mg for CORN in the hair matrix. Analysis of authentic wolf hair samples revealed CORT and CORN concentrations in the ranges of <4.13–11.86 pg/mg and <2.49–3.67 pg/mg, respectively. The CORT results showed a strong positive correlation with those obtained using enzymatic immunoassays. The method may be applied to assess the impact of stressors on the welfare of wolves, e.g., providing a useful tool for monitoring recovering European populations as they face new challenges associated with expansion into potentially suboptimal habitats. Full article

Traumatic brain injury (TBI) disrupts brain metabolism, which evolves over time and varies with the severity of the injury. Monitoring these metabolomic changes may reveal biomarkers indicating early damage, mechanisms of injury, and potentially help predict outcomes. This study used untargeted plasma metabolomics to investigate systemic time-dependent metabolic changes in mice exposed to controlled cortical impact (CCI) with or without replacement of a modified skull cap designed to reduce compensatory space for cerebral edema modelling a severe closed skull TBI, compared to sham controls. Male mice were subjected to CCI, CCI + CAP, or sham procedures comprised a scalp incision or a craniotomy. Plasma samples were collected at 4, 8, and 16 h, and 3 and 7 days after injury. Hydrophilic interaction liquid chromatography–mass spectrometry (HILIC-MS) was used to profile metabolites in all groups and time points, while ion-pair liquid chromatography–mass spectrometry (RPIPLC-MS) was used in CCI and sham mice at the early time points. The largest metabolic changes occurred at 8 h post-injury, distinguishing mice with CCI from sham controls. The early changes concerned metabolism of amino acids, energy, and nucleotide pathways, with metabolites such as succinate, phenylalanine, and cytidine showing significant changes. By 7 days, the metabolic patterns of the injured mice, especially CCI mice, had partially converged toward the sham state, although oxidative and mitochondrial disturbances persisted. The CCI + CAP mice had more pronounced and persistent metabolic disturbances compared to the CCI mice, which may reflect the effect of increased intracranial pressure post-injury. Plasma metabolomics can efficiently capture the evolving biochemical effects of TBI. The findings identified circulating metabolites that were associated with progression and severity of brain injury and provide a basis for future translational studies in human TBI. Full article

Malignant pleural mesothelioma (MPM) is an aggressive pleural tumor associated with asbestos exposure. Poor clinical outcome of MPM is often driven by late-stage diagnosis due to non-specific clinical presentation, similarity to pleural lesions (e.g., inflammatory changes, metastatic adenocarcinoma), and limitations of current diagnostic methods. We employed Fourier transform infrared (FTIR) spectroscopy combined with convolutional neural networks (CNNs) to analyze formalin-fixed paraffin-embedded (FFPE) pleural tissue samples from patients with MPM, metastatic adenocarcinoma, pleural inflammation, and normal (healthy) pleura. Glycan analysis of FFPE normal pleura and MPM was performed using ultra-high-performance liquid chromatography (UPLC) and mass spectrometry (MS). Our FTIR-spectral analysis uncovered a strong spectral fingerprint of MPM that was especially apparent in the region typical for C-O and C-C stretches as well as local symmetry region typical for deformation vibrations of CH₂ and C-OH groups, all appearing in carbohydrates. Our orthogonal validation of these findings through a targeted glycomics approach using UPLC confirmed that the MPM N-glycome exhibits a distinct fingerprint that distinguishes it from normal pleural tissue. Through utilization of MS for identifying the exact structures of differentially expressed N-glycan peaks, we also identified two high-mannose N-glycan structures that show a specific biomarker potential for MPM and need to be examined in future studies. Full article

Whole blood (WB) storage induces biochemical and biomechanical alterations that may compromise red blood cell (RBC) quality. Since oxidative stress is a major driver of storage lesions, we investigated whether N-acetylcysteine (NAC) could attenuate these changes during refrigerated storage. WB from healthy donors was stored at 4 °C for 42 days with or without NAC, added either once at baseline or every 10 days. Plasma albumin proteoforms were assessed by liquid chromatography–mass spectrometry, free hemoglobin species by spectrophotometry, plasma proteomic changes by proximity extension assay, and RBC hemorheological properties by LORRCA analysis. Storage decreased reduced albumin (HSA-SH) and increased oxidized albumin (HSA-Cys), indicating plasma oxidation. Free oxyhemoglobin, deoxyhemoglobin, and methemoglobin increased, consistent with hemoglobin oxidation and hemolysis. Storage also induced plasma proteomic alterations and impaired RBC osmotic and deformability parameters. NAC preserved albumin redox status, limited free hemoglobin accumulation, and attenuated storage-induced proteomic changes. Moreover, NAC partially preserved RBC osmotic and rheological properties, particularly parameters related to osmotic fragility and hydration. No clear advantage of 20 mM over 10 mM NAC was observed. Overall, NAC attenuated oxidative and functional alterations associated with refrigerated whole blood storage, supporting further investigation of antioxidant supplementation as a strategy to mitigate storage lesions under ex vivo conditions. Full article

Urban water security in many cities in the Global South is increasingly challenged by ageing infrastructure and the presence of persistent chemical contaminants. This study investigated the Harare metropolitan water continuum between 2020 and 2024 using a longitudinal, systems-oriented observational framework encompassing wastewater discharge, surface water reservoirs, drinking water treatment, and municipal distribution networks. A three-stage approach was employed, comprising qualitative screening for selected pharmaceuticals at the Lake Chivero water–sediment interface in 2020, spatial assessment of physicochemical stability across the treatment and distribution system in 2021, and targeted qualitative evaluation of pharmaceutical and agrochemical occurrence in wastewater-impacted matrices in 2024. Sulfamethoxazole and trimethoprim were qualitatively identified using high-performance liquid chromatography (HPLC), while atrazine was confirmed by gas chromatography–mass spectrometry (GC–MS). These analyses indicated the continued presence of pharmaceutical and agrochemical residues within wastewater-impacted aquatic compartments associated with the Harare water supply. Physicochemical monitoring revealed elevated ammonia concentrations and reduced free residual chlorine across sections of the distribution network. These conditions coincided with detectable heterotrophic bacterial regrowth at distal consumer endpoints. Phenotypic antimicrobial susceptibility testing of bacterial isolates recovered at the source interface showed limited inhibition responses to sulfamethoxazole and trimethoprim under the experimental conditions used. While the observational nature of this study precludes causal inference, the co-occurrence of chemical residues, physicochemical instability, and bacterial isolates exhibiting reduced inhibition responses highlights conditions of potential relevance for antimicrobial resistance risk within wastewater-influenced urban water systems. These findings underscore the importance of integrated water management strategies addressing wastewater control, source water protection, and distribution system integrity within a One Health context. Full article

Alterations in microbiota, transcript and metabolites are critical to intestinal homeostasis and host health. This study used a combination of 16s rRNA, transcriptome sequencing and liquid chromatography–mass spectrometry to investigate intestinal microbiota, genes and metabolic profiles in the ileum of Hu sheep fed broccoli extract. Here, we randomly allocated 14 Hu sheep to two diets: a basal diet without any supplementation (NC) and a basal diet supplemented with 200 mg/kg broccoli tail (BT). After 60 days of treatment, blood and jejunal samples were collected for serum biochemical indicators and multi-omics analysis. In this study, the extract of broccoli tails had a significant effect on the serum biochemical indicators, including white blood cells, red blood cells, mean corpuscular volume, mean corpuscular hemoglobin concentration, mean platelet volume, triglycerides and total protein in Hu sheep (p < 0.05). Transcriptomic analysis showed that the 672 differentially expressed genes between the NC and BT groups were primarily enriched in linoleic acid metabolism, steroid hormone biosynthesis, and cholesterol metabolism. Metabolomics analysis using Kyoto Encyclopedia of Genes and Genomes enrichment showed that the 41 differentially abundant metabolites were mainly enriched in bile secretion, vitamin B6 metabolism, and the mTOR signaling pathway. 16S rRNA sequencing results indicated that the extract of broccoli tails increased the relative abundance of Peptostreptococcaceae and decreased the relative abundance of Lachnospiraceae, Lachnospirales, and Bacteroidaceae. Integrated transcriptome, metabolome, and microbiome analysis showed that the gut microbiota and host transcriptomic changes may participate in systemic metabolic regulation by modulating amino acid metabolism, lipid signal transduction, nucleotide metabolism, and vitamin B6-related metabolic pathways. These findings demonstrate that the extract of broccoli tails modulates intestinal gene expression, systemic metabolism, and gut microbial ecology in Hu sheep, providing new insights into the utilization of agricultural byproducts as a functional feed supplement for ruminants. Full article

Background/Objectives: Niclosamide is an U.S. Food and Drug Administration (FDA)-approved antihelminthic drug with a long-established safety profile and demonstrated in vitro antiviral activity against Zika virus. Its evaluation for systemic indications has been limited by its poor oral bioavailability. This Phase I study assessed whether oral administration of the approved niclosamide formulation could achieve plasma concentrations comparable to those with reported antiviral activity. Methods: This single-center, open-label, randomized, two-period crossover Phase I study evaluated the safety, tolerability, and pharmacokinetics of oral niclosamide in healthy adult volunteers. Twelve participants received niclosamide 2 g once daily for three consecutive days under fed or fasted conditions, followed by crossover after a 14-day washout period. Plasma niclosamide concentrations were quantified using a validated Liquid Chromatography-Mass Spectrometry (LC–MS/MS) assay, and pharmacokinetic parameters were derived via non-compartmental analysis. Safety assessments included adverse event monitoring, clinical laboratory testing, vital signs, electrocardiograms, and physical examinations. Results: Nine participants per protocol completed the study. Niclosamide was safe and well tolerated under both fed and fasted conditions, with only mild to moderate, transient adverse events and no serious or severe events. Systemic exposure was markedly higher following fed administration, with mean maximum observed plasma concentration (C_max) and Area Under the Curve (AUC) values several-fold greater than those observed under fasted conditions. Under fed conditions, mean plasma niclosamide concentrations exceeded the reported in vitro Zika virus half-maximal inhibitory concentration (IC₅₀₎ (0.22 µM) for approximately 9 h post-dose on both Day 1 and Day 3. Fasted administration did not consistently achieve this exposure threshold. No unexpected accumulation was observed with repeated once-daily dosing. Conclusions: Oral niclosamide administered at the approved daily dose of 2 g is safe and well tolerated in healthy volunteers. Administration with food substantially enhances systemic exposure and transiently achieves plasma concentrations associated with in vitro antiviral activity against Zika virus. These findings support further development of optimized niclosamide formulations to achieve sustained systemic exposure for antiviral therapeutic applications. Full article

Background: H₂ gas inhalation has been proposed as a selective modulator of reactive oxygen species (ROS), potentially mitigating treatment-related oxidative damage. This study investigated the effects of adjunctive H₂ gas inhalation on serum metabolomic profiles and clinical toxicities in patients with LAHNC undergoing CCRT. Methods: Twenty patients were prospectively randomized to receive either standard CCRT alone (Group A) or CCRT combined with adjunctive H₂ gas inhalation (Group B). Serum samples collected before and after treatment were analyzed using untargeted ultra-high-performance liquid chromatography coupled with ion mobility quadrupole time-of-flight high-resolution mass spectrometry (UHPLC-IM-QTOF-HRMS)-based metabolomics. Results: One patient in Group B discontinued participation, leaving 19 patients for the final analysis. Patients receiving adjunctive H₂ gas inhalation tended to exhibit numerically lower frequencies of moderate treatment-related toxicities, fewer chemotherapy delays, and a shorter overall treatment duration than those receiving CCRT alone. Metabolomic profiling in the CCRT-alone group revealed exploratory alterations in metabolites associated with arginine metabolism, glutathione metabolism, and purine metabolism following treatment. Ornithine, uric acid, and tetrahydrodeoxycorticosterone were among the candidate discriminative metabolites with exploratory discriminatory performance after CCRT. In contrast, patients receiving adjunctive H₂ gas inhalation showed a more limited pattern of pathway mapping, with exploratory evidence from an illustrative single-hit pathway assignment suggesting possible involvement of purine metabolism. Altered uric acid levels together with changes in several lipid-related metabolites may collectively reflect metabolic responses associated with treatment-related oxidative stress during CCRT. Consistent with these findings, direct between-group comparison of within-subject changes (Δ = post − pre) indicated a numerically smaller reduction in serum uric acid levels in the adjunctive H₂ gas inhalation group; however, this difference did not reach statistical significance. Conclusions: Adjunctive H₂ gas inhalation during CCRT may be associated with reduced moderate treatment-related toxicities and exploratory changes in systemic metabolic profiles in patients with LAHNC. However, the study was not designed to evaluate oncological outcomes, and the metabolomic findings, particularly the pathway-level interpretations, should be considered exploratory because several pathway assignments were based on only one or a few mapped metabolites, together with the limited sample size, patient heterogeneity, and lack of independent external validation. Further validation in larger, independent cohorts using comprehensive between-group metabolomic analyses is warranted. Full article

Background/Objectives: Tripterygium glycosides (TG) are used to treat inflammatory and autoimmune diseases, but their clinical application is limited by toxicity and the lack of process-responsive quality markers. This study examined whether roasting and dealkalization remodel the TG metabolite profile and alter the post-dose serum profile of circulating prototype constituents. Methods: Self-prepared TG, roasted TG (RTG), roasted–dealkalized TG (RDTG), and five marketed products were profiled by ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS). Seven representative compounds were quantified by validated high-performance liquid chromatography (HPLC). Rat serum after oral administration was analyzed to compare circulating prototype constituents. Results: We characterized 243 constituents in material samples and 63 circulating prototype constituents in serum. Roasting primarily reshapes the profiles of diterpenoids and triterpenoids. Celastrol was not detected in the RTG and RDTG material samples, nor in the corresponding single-time-point serum profiles under the current analytical conditions. In contrast, wilforlide A exhibited an increase in material samples. Dealkalization preferentially reduced alkaloid-related constituents, including wilforine in material samples and tripterygiumine T in serum. Conclusions: Integrated material profiling, targeted quantification, and serum prototype analysis identified candidate process-responsive markers for processed TG preparations. Because the serum study was based on relative signal intensities rather than full pharmacokinetics, these markers require further pharmacokinetic and toxicological validation. Full article

Background and Objectives: Hypoxia-inducible factor-1 alpha (HIF-1α) is a central regulator of cellular responses to hypoxia and has been implicated in the pathophysiology of several neurological disorders. Parkinson’s disease (PD) and restless legs syndrome (RLS) have both been associated with alterations in oxygen sensing, mitochondrial dysfunction, and disturbances in amino acid metabolism; however, the relationship between HIF-1α and amino acid metabolic pathways in these disorders remains incompletely understood. The present study investigated circulating HIF-1α concentrations and amino acid metabolite profiles in patients with PD and RLS. Materials and Methods: In this cross-sectional study, 55 participants were enrolled, including 30 healthy controls, 12 patients with PD, and 13 patients with RLS. Plasma HIF-1α concentrations were measured using an enzyme-linked immunosorbent assay, and amino acid metabolites were quantified by liquid chromatography–tandem mass spectrometry. Group comparisons were performed using non-parametric methods with FDR correction. Age- and sex-adjusted regression analyses, correlation analyses, and PCA were used to assess metabolic relationships and group discrimination. Results: Significant group differences were observed for HIF-1α and multiple amino acid metabolites. Compared with controls, both PD and RLS patients exhibited significantly higher concentrations of arginine, citrulline, homocitrulline, and HIF-1α, whereas ornithine concentrations were significantly lower. Arginine demonstrated the largest effect size among all biomarkers (ε² = 0.713). HIF-1α concentrations showed a progressive increase across groups, with the highest levels observed in RLS. Correlation analyses revealed strong positive associations of HIF-1α with arginine, citrulline, and homocitrulline, and an inverse association with ornithine. These findings remained significant after adjustment for age and sex. PCA showed clear separation between controls and disease groups. Conclusions: PD and RLS are characterized by a shared metabolic signature involving elevated HIF-1α, increased arginine-pathway metabolites, and reduced ornithine concentrations. The detected associations between HIF-1α and metabolites of the arginine–citrulline–ornithine pathway suggest a potential link between hypoxia-related signaling and metabolic dysregulation in both disorders. These findings support further investigation of HIF-1α-associated metabolic pathways as potential biomarkers and therapeutic targets in neurodegenerative and movement disorders. Full article

Background/Objectives: Styphnolobium japonicum cv. Jinhuai (SJvJ) represents a medicinal and edible plant whose metabolite composition is strongly shaped by its growing location. Current quality control methods mainly rely on rutin quantification, lacking comprehensive metabolic markers for origin discrimination. Therefore, this study aimed to profile interregional metabolic differences between Guangxi and Sichuan SJvJ flower buds, identify characteristic differential markers, and clarify relevant metabolic pathways, thereby guiding quality control, germplasm evaluation, and functional food development. Methods: Ultra-high performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) was employed to identify metabolites. The Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and Cancer HSP were applied to screen the key active ingredients of traditional Chinese medicine (TCM-KAIs) and disease-related pharmaceutical ingredients (PDRIs). Specifically, we targeted six highly prevalent human diseases and another five disorders based on therapeutic indications documented in the Chinese Pharmacopoeia. Multivariate analyses, such as principal component analysis, hierarchical clustering analysis, and other statistical methods, were applied to investigate differential metabolites. The Kyoto Encyclopedia of Genes and Genomes (KEGG) database was utilized for pathway enrichment analysis of marker metabolites. Results: In total, 1550 metabolites were identified across 12 categories, predominantly flavonoids. Additionally, 152 TCM-KAIs and 204 PDRIs against 11 diseases were screened. Multivariate analyses indicated that geographical origin was closely associated with observed metabolic variation among the tested samples: Guangxi samples accumulated higher lipids and nucleotides, whereas Sichuan samples showed higher levels of flavonoids and phenolic acids. Vanilloloside, protocatechuic acid-4-O-glucoside, and gallic acid-4-O-glucoside were identified as key inter-group biomarkers. KEGG enrichment analysis revealed enhanced metabolism of nucleotide/pyrimidine in Guangxi, whereas zeatin biosynthesis was upregulated in Sichuan, consistent with discrepancies in regional climatic patterns. Conclusions: This study established a more comprehensive metabolomic dataset for FBSJvJ. It also clarified the correlations between origin and quality and unraveled the underlying mechanisms. These findings facilitate origin authentication, standardized quality control, and rational exploitation of FBSJvJ as raw materials of functional foods. Full article

An analytical method was established for the rapid determination of 45 pigments and preservatives in edible ink by ultra-high performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry (UHPLC-MS/MS), which provides technical support for the composition analysis and industrial development of edible ink. The samples were easily extracted with 75% aqueous methanol solution and purified with a Captiva EMR-Lipid HF solid-phase extraction cartridge. After filtration through a polytetrafluoroethylene (PTFE) membrane, the analytes were determined by UHPLC-MS/MS under multiple reaction monitoring (MRM) mode in both positive and negative ion modes. Poroshell 120 AQ-C18 was selected as the analytical column, and valve switching timing control was adopted during the gradient elution process. The external standard method was used for quantitative analysis. In the established method, the 45 pigments and preservatives exhibited good linear relationships within the mass concentration range of 0.0002–200.0 μg/mL. The limits of detection (LOD) and limits of quantification (LOQ) were 0.0004–8.00 mg/kg and 0.001–20.00 mg/kg, respectively. Using 25% aqueous glycerol solution as the blank matrix, the recoveries of analytes at different spiked levels met the detection requirements. The established method is simple and rapid, and can be applied to the qualitative and quantitative detection of typical pigments and preservatives in edible ink. Full article

Background/Objectives: Dolphins inhabiting coastlines can be influenced by anthropogenic factors. As biochemical changes accumulate in blubber over weeks to months, blubber metabolites may be informative biomarkers of molecular adaptations to environmental changes. Methods: We investigated the blubber metabolomic signatures of live free-ranging bottlenose dolphins for the first time. This exploratory study analyzed blubber samples from 35 common bottlenose dolphins (Tursiops truncatus) in South Texas waters using untargeted ultra-high-performance liquid chromatography-Orbitrap metabolomics. Results: Blubber samples exhibited distinct temporal and spatial metabolic patterns. Pathway enrichment analyses comparing detected metabolites (n = 2777) revealed that dolphins sampled in the spring had enhanced lipid quality and immune regulation, while dolphins sampled in the summer showed stress-associated metabolic responses. Dolphins inhabiting areas previously reported to experience heavy vessel traffic and contaminant burdens exhibited enriched immune- and inflammation-associated pathways. Dolphins that visually appeared to have poorer body condition exhibited metabolite profiles suggestive of increased protein catabolism. Dolphins in extreme salinity conditions had more abundant membrane maintenance and endocrine pathways. Conclusions: Dolphins from each system exhibited distinct metabolic signatures that may be associated with differing physiological responses, highlighting the potential utility of blubber biomarkers for assessing physiological adaptations in free-ranging marine mammals. Improved understanding of habitat-specific physiological responses offers critical insights into how cumulative impacts may affect the health and adaptive capacity of vulnerable species in dynamic coastal ecosystems. Full article

Background: Vitamin D is a key regulator of skeletal homeostasis, and hypovitaminosis D is highly prevalent among postmenopausal women, who are at increased risk of osteoporosis, sarcopenia, and related complications. Accurate assessment of serum 25-hydroxyvitamin D [25(OH)D] is therefore essential. However, substantial variability exists among analytical methods, particularly between automated chemiluminescent immunoassays (CLIA) and liquid chromatography–tandem mass spectrometry (LC-MS/MS), the latter considered the reference technique. This study aimed to compare four analytical methods, three CLIA platforms, and LC-MS/MS for measuring circulating 25(OH)D levels in a cohort of menopausal and postmenopausal women. Methods: A total of 425 serum samples from menopausal and postmenopausal women representing the real-world distribution of vitamin D levels in this population were analyzed using three automated CLIA systems and LC-MS/MS. Method comparison, agreement, precision through quality control assessment, total error, and sigma were evaluated. Results: The evaluated CLIA platforms (Abbott, Snibe, and Siemens) showed strong correlation with LC-MS/MS, with r = 0.919, r = 0.978, and r = 0.879. Furthermore, all assays showed excellent precision (CV < 5%), with good-to-acceptable total error (TE) and Sigma-metric performance. Conclusions: In conclusion, these findings demonstrate that while CLIA platforms offer a reliable and precise alternative for routine clinical use, these findings underscore the importance of method selection and result interpretation in the clinical assessment of vitamin D status in postmenopausal women. Furthermore, it highlights the ongoing need to minimize inter-assay variability and ensure consistent vitamin D assessment. Full article