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Comparative safety of lipid-lowering drugs alone or in combination: insights from a systematic review and network meta-analysis.

BACKGROUND AND AIMS: Although the safety profile of lipid-lowering therapies (LLTs) is known, there are no comprehensive comparative assessments. We aimed to compare the risk of muscle-related events, diabetes, liver dysfunction, and cognitive disorders among LLTs through a network meta-analysis. METHODS AND RESULTS: Databases were searched from inception to May 2025. Eligible studies included adult patients, using statins, ezetimibe, PCSK9 monoclonal antibodies (PCSK9mAbs), inclisiran, bempedoic acid, or their combinations as intervention, reporting the information about any of the selected adverse events, a total sample size of ≥200 subjects, and had ≥1 month of intervention. Pooled estimates were assessed by fixed effects model within a frequentist setting. Pooled relative risks (RR) and their 95% confidence interval were estimated. A total of 303,397 subjects from 153 RCTs were included. Bempedoic acid ranked the lowest risk of myalgia (vs PCSK9mAbs, RR 0.80 [0.69, 0.93]). PCSK9mAbs were associated with lower incidence of creatine kinase (CK) elevation, diabetes, and liver dysfunction comparing to statins (statins vs PCSK9mAbs, RR 1.44 [1.14, 1.81], RR 1.13 [1.05, 1.22], and RR 1.38 [1.17, 1.62], respectively). In terms of muscle-related events and cognitive disorders, no significant risk differences were found among treatments and their combinations. CONCLUSIONS: PCSK9mAbs appear to have a more favourable safety profile regarding the risk of CK elevation, diabetes, and liver dysfunction. Bempedoic acid seem to be a better choice for subjects with high risk of myalgia. This information can be valuable when selecting therapy for specific patient subgroups at higher risk of certain adverse events.

Humans

Bempedoic Acid and First and Recurrent Limb Outcomes in Statin-Intolerant Patients With Peripheral Artery Disease: Insights From the CLEAR Outcomes Trial.

BACKGROUND: Patients with peripheral artery disease (PAD) are at high risk of major adverse limb events (MALE) and major adverse cardiovascular events (MACE). Recently, bempedoic acid was shown to reduce MACE in primary and secondary prevention patients. Whether bempedoic acid reduces the risk of MALE in patients with PAD is unknown. METHODS: CLEAR Outcomes (Cholesterol Lowering via Bempedoic Acid [ETC1002], an ACL-Inhibiting Regimen) randomized 13 970 patients to bempedoic acid 180 mg or placebo from December 22, 2016, to August 14, 2019. The trial primary end point was MACE-4, defined as death resulting from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or coronary revascularization. A clinical history of PAD was reported by investigators at baseline. Two blinded vascular medicine specialists independently adjudicated MALE, including adverse events indicating worsening PAD symptoms leading to revascularization, chronic limb-threatening ischemia, and acute limb ischemia. Outcomes were assessed as time to first event and total (including recurrent) events with a negative binomial approach. RESULTS: A total of 1624 of the enrolled patients (mean±SD age, 63.9±9.9 years; 915 [56.3%] female) had PAD at baseline. In patients with PAD in the placebo group, 69 (8.3%) had MALE over a median of 40.6 months, with rate of recurrent events of 4.0%/y. Bempedoic acid reduced the risk of MALE by 36% (hazard ratio, 0.64 [95% CI, 0.44-0.93]; P=0.018). Bempedoic acid reduced total MALE by 45% (relative risk, 0.55 [95% CI, 0.35-0.85]; P=0.007). First MACE-4 or MALE was reduced overall by 13% (hazard ratio, 0.87 [95% CI, 0.80-0.95]) with consistent effects with PAD (hazard ratio, 0.82 [95% CI, 0.64-1.04]) and without PAD (hazard ratio, 0.87 [95% CI, 0.79-0.86]; Pinteraction=NS) but not statistically significant within the PAD subgroup alone. Total MACE-4 or MALE was reduced (relative risk, 0.81 [95% CI, 0.73-0.90]) overall with consistent effects in PAD (relative risk, 0.71 [95% CI, 0.54-0.95]) and without PAD (relative risk, 0.82 [95% CI, 0.73-0.92]; Pinteraction=NS). CONCLUSIONS: Patients with PAD are at high risk of MALE and MACE. Bempedoic acid reduces both MACE and MALE in patients with atherosclerotic vascular disease, with notable absolute benefits in patients with PAD. These findings support (1) the importance of lowering low-density lipoprotein cholesterol in patients with PAD to reduce overall vascular risk and (2) the benefits of bempedoic acid in this population.

Humans

Carboxyl group number and acidity of organic acids regulate structural reorganization and low glycemic index in cassava pyrodextrins via molecular interactions.

Transforming high-glycemic cassava starch into functional dietary fiber via pyrodextrinization is a promising way to valorize tuber crops, yet the molecular mechanisms catalyzed by organic acids with different carboxyl numbers and acidity remain unclear. This study investigates how carboxyl number and acidity of acetic acid (AA), tartaric acid (TA), and citric acid (CA) affect structural reorganization and low glycemic properties of cassava pyrodextrins. Compared with AA, TA, and CA with stronger acidity and more carboxyl groups promoted more extensive hydrolysis, transglycosylation, repolymerization, and esterification. These changes increased indigestible glycosidic linkages and the branching degree, while reducing molecular weight. Molecular docking confirmed stronger hydrogen-bonding interactions between TA/CA and starch chains. Furthermore, TA- and CA-catalyzed pyrodextrins exhibited superior anti-digestive properties with resistant starch up to 54.26% and an estimated glycemic index as low as 42.46, highlighting the critical role of carboxyl numbers and acidities in modulating the functionality of pyrodextrins.

Manihot

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

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

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

BIOCARD framework: integrating fecal bile acids, lipids, and metabolites to assess response to a cardiovascular health intervention.

Cardiovascular disease (CVD) remains a leading cause of morbidity and mortality, particularly in under-resourced populations. Although nutritional interventions are important for CVD prevention, their outcomes are commonly evaluated using conventional clinical and behavioral indicators, which may not fully capture early molecular responses. In this study, we developed the BIOCARD framework, an exploratory fecal multi-omics platform integrating bile acids, lipids, and metabolites to evaluate intervention outcomes related to cardiovascular health. Fecal samples were collected from caregiver-child participants enrolled in a 10-week randomized controlled trial comparing a multicomponent garden-based intervention (SHA) with an education-only control group (MSP). Fecal polar metabolites, lipids, and bile acids were analyzed by UHPLC-HRMS-based approaches and integrated with conventional health indicators. Traditional clinical indicators in the present study showed limited sensitivity for detecting intervention-related differences. In contrast, fecal multi-omics analyzes revealed intervention-associated differences in metabolites, lipids, and bile acids, with children showing more apparent molecular variation than parents. Network analysis further revealed associations between selected molecular features and cardiovascular-related indicators, including blood pressure, body fat, skin carotenoids, and Healthy Eating Index scores. Together, these findings suggest that the BIOCARD framework may serve as an exploratory molecular approach to complement traditional outcome measures and improve the evaluation of nutritional interventions for cardiovascular health.

Humans

Evolutionary characterization and expression profiling of ACC and FASN genes in Chinese mitten crab Eriocheir sinensis.

Acetyl-CoA carboxylase (ACC) and fatty acid synthase (FASN) are rate-limiting enzymes in the fatty acid biosynthetic pathway, yet their evolutionary relationships, sequence features, and expression profiles remain poorly understood in crustaceans, particularly in the economically important Chinese mitten crab (Eriocheir sinensis). Here, we identified and systematically analyzed ACC and FASN genes in E. sinensis using comparative genomic analyses across 43 species. ACC was highly conserved as a single-copy gene in invertebrates, in contrast to the multiple paralogs observed in vertebrates. Similarly, FASN was generally maintained as a single-copy gene across most taxa but exhibited lineage-specific expansion in certain insect groups. Phylogenetic and structural analysis revealed strong conservation of both genes within crustaceans, supported by multiple conserved motifs and canonical functional domains. Expression profiling showed predominant expression in the hepatopancreas and midgut, suggesting their potential involvement in crustacean lipid metabolism. During the molting cycle, ACC and FASN exhibited higher expression levels during stages C and D, suggesting an increased capacity for fatty acid biosynthesis before molting. In addition, dietary lipid levels experiment revealed that ACC and FASN expression responded dynamically to dietary lipid availability, with increased expression at moderate lipid levels but reduced expression under excessive lipid supplementation, indicating a possible adaptive transcriptional response to lipid status. Collectively, this study provides insights into the evolutionary conservation and expression dynamics of ACC and FASN and improves our understanding of lipid metabolic adaptation in crustaceans.

Animals

Prophylactic folinic acid prevents pemetrexed myelosuppression: A randomized trial toward safer treatment with chemotherapy in non-small cell lung cancer.

Background Pemetrexed is a cornerstone in advanced non-small cell lung cancer treatment. Although generally well tolerated, severe myelosuppression occurs in 26% of patients. Preventing chemotherapy-associated toxicity has become increasingly important with the introduction of osimertinib combined with pemetrexed-based chemotherapy. Due to substantial toxicity, this regimen is often not administered to frail patients. Folinic acid prophylaxis can mitigate pemetrexed-induced toxicity, however its preventive use has not been routinely studied. We aimed to investigate the efficacy of folinic acid prophylaxis to reduce myelosuppression. Methods Fifty patients treated with pemetrexed were randomized (1:1) to receive pemetrexed with or without oral folinic acid prophylaxis on days 2-4 after each chemotherapy cycle. The primary endpoint was absolute neutrophil count (ANC) after the first chemotherapy cycle. Secondary endpoints included ANC after the second cycle, grade neutropenia, treatment efficacy, renal function and incidence of dose modifications. Results Twenty-four patients received folinic acid and twenty-six served as controls. Higher ANC were observed in the folinic acid group after the first cycle (median 3.79; IQR 2.22-4.93 vs. 1.85; IQR 1.43-3.78; p.

Humans

Vegan multinutrient supplementation significantly increases Omega-3 index and 25-OH-vitamin D status: a randomized, double-blind, placebo-controlled trial in healthy young vegans.

In this randomized, double-blind, placebo-controlled trial, 72 healthy vegan adults (aged 19-57 years) received a multinutrient supplement consisting of a vitamin and mineral supplement (providing 26 &#xb5;g vitamin D) and an omega-3 supplement administered in either a single dose (EPA 98.7 mg, DHA 171.0 mg, additional vitamin D 36 &#xb5;g, vitamin E 3.7 mg) or a double dose (EPA 197.4 mg, DHA 342.0 mg, additional vitamin D 72 &#xb5;g, vitamin E 7.4 mg) or placebo capsules for 4 months. Nutrient biomarkers were assessed at baseline and at the end of the intervention after 4 months. An analysis of covariance was employed to test for between-group differences (p < 0.05) and adjusted for multiple testing using the Bonferroni-Holm method. Compared to the control group, which showed on average a significant decline in both the omega-3-index and 25-hydroxyvitamin D, participants in both intervention groups demonstrated significant increase in these parameters (p < 0.001). Although the double dose group exhibited numerically greater increases in omega-3 index and vitamin D compared to the simple dose group, the differences between these dosing regimens were not statistically significant. As expected, vitamin E levels remained unchanged, reflecting its inclusion solely for antioxidative protection in the omega-3 supplement rather than as a critical nutrient in vegan diets. In conclusion, supplementation significantly improved omega-3 and vitamin D status in healthy vegans, with no significant benefit from doubling the dose. Although clinical endpoints were not evaluated, improved nutrient status may have potential implications for health. The study has been registered at the German Clinical Trials Register (DRKS00028151).

Humans

Proteomic insights into hepatic responses to high soybean meal inclusion with citric acid supplementation in hybrid grouper (Epinephelus fuscoguttatus&#xa0;&#xd7;&#xa0;Epinephelus lanceolatus) juveniles.

This study evaluated the growth performance and hepatic proteomic responses of juvenile hybrid grouper (Epinephelus fuscoguttatus&#xa0;&#xd7;&#xa0;Epinephelus lanceolatus) juveniles fed diets containing 30% or 40% soybean meal (SBM), with or without 3% citric acid supplementation, and compared with a fishmeal (FM) control diet over a 10-week feeding trial. Fish fed 30% SBM (LSBM) showed a final body weight comparable to the FM group, whereas fish fed 40% SBM (HSBM) recorded significantly reduced growth and net protein utilization (NPU) (p&#xa0;<&#xa0;0.05). Supplementation of citric acid in the 40% SBM diet (HSBM + CA) significantly improved NPU and partially restored growth relative to HSBM. LC-MS/MS based quantitative proteomics identified 1544 hepatic proteins and showed clear dietary segregation. Differentially expressed proteins were predominantly associated with reduced abundance of proteins involved in lipid metabolism, amino acid metabolism, pyruvate metabolism, and the tricarboxylic cycle across all SBM diets, suggesting a shift in oxidative metabolic capacity. In contrast, LSBM induced upregulation of spliceosome-associated proteins and RNA processing components, suggesting adaptive post-transcriptional regulation under moderate SBM inclusion. In contrast, HSBM exhibited greater reduction in metabolic protein abundance without comparable upregulation of adaptive regulatory components, coinciding with reduced nutrient retention. Protein-protein interaction analysis further confirms the correlation between the regulation of spliceosomal clusters and mitochondrial lipid-catabolic modules. Citric acid supplementation did not markedly reverse hepatic metabolic protein changes but improved protein retention. Data are available via ProteomeXchange with identifier PXD081994. These findings suggest a tolerance limit between 30% and 40% SBM inclusion, with 30% inducing adaptive hepatic proteomic responses compatible with maintained growth performance.

Animals

Multiomic insights into fungal polylactic acid degradation: Metabolic adaptation and hydrolytic mechanisms of Sporobolomyces pararoseus.

Polylactic acid (PLA), a biodegradable polyester from renewable resources, is a sustainable alternative to petrochemical plastics. However, its environmental degradation is inefficient naturally, requiring specific microbial activities. While bacterial PLA-degrading mechanisms are well documented, fungal degrading systems-particularly their molecular mechanisms-are underexplored.We isolated Sporobolomyces pararoseus ZRQ01 from the gut microbiota of PLA-fed mealworms. This fungal strain noticeably degraded PLA in PLA-containing medium supplemented with 2% glucose. Biodegradation assays revealed 22.8% loss of the PLA film weight after 35&#xa0;days of incubation, and scanning electron microscopy confirmed extensive surface erosion and pore formation. Integrated transcriptomic and proteomic analyses, together with the reference genome of S. pararoseus ZRQ01, revealed that S. pararoseus ZRQ01 upregulates hydrolytic enzymes at both transcript and protein levels to cleave PLA into lactic acid. After lactic acid is transferred into S. pararoseus ZRQ01 cells by monocarboxylate transporters with increased abundance, it is assimilated by pathways of pyruvate metabolism and the TCA cycle with increased protein abundance. Intriguingly, upregulation of genes in autophagy-related and MAPK signaling pathways underscores an adaptive stress response potentially supporting cellular homeostasis and degradation-related gene expression. Our results highlight S. pararoseus ZRQ01's metabolic potential for bioremediation and offer insights into fungal bioplastic degradation pathways.

Polyesters

Comprehensive identification of carboxylic acids by using bromine isotope-based chemical isotope labelling and structure-guided molecular network.

Carboxylic acids (CAs) are important contributors to the flavor quality of sauce-flavor Chinese Baijiu, yet their comprehensive analysis remains challenging due to poor ionization efficiency, weak chromatographic retention, and limited annotation capability. Herein, we developed a workflow for the high-coverage discovery and annotation of CAs in Baijiu by coupling chemical isotope labeling-liquid chromatography-mass spectrometry with a structure-guided molecular network strategy (SGMNS). A bromine-containing derivatization reagent, 1-(3-aminopropyl)-3-bromoquinolin-1-ium bromide (APBQ), was designed and synthesized to exploit the natural isotope distribution of bromine and characteristic MS/MS fragmentation behavior. Following APBQ derivatization, the target CAs showed superior chromatographic retention and favorable analytical performance. Based on isotopic peak pairing in MS1 and diagnostic fragment validation in MS2, 372 potential CA derivatives were discovered from pooled Baijiu samples and 355 of them were validated by diagnostic fragments in MS2 spectra. To address the scarcity of derivatized spectral libraries, SGMNS was employed for annotation using a background network constructed from APBQ-labeled candidates derived from the Expanded Chinese Baijiu Compound Database. The developed method was further applied to profile Baijiu samples, revealing pronounced differences in CA composition across the seven fermentation rounds. Notably, rounds 3 to 5 exhibited the largest numbers of differential CAs. This study provided an effective analytical strategy for large-scale CA profiling, offering new insight into the chemical basis of flavor formation during multi-round fermentation of sauce-flavor Baijiu.

Isotope Labeling

Improved comprehensive profiling of fecal bile acids through chemical derivatization combined with HPLC-MS/MS analysis.

Bile acids (BAs) facilitate the digestion and absorption of fats and influence lipid and glucose homeostasis, making them potential therapeutic targets for obesity and related metabolic disorders. The liver and intestinal microbiota modify BAs structurally, generating diverse chemical forms and isomers. Comprehensive profiling of the BA pool is critical for understanding their key biological functions and as a therapeutic approach for related diseases. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) is usually chosen as the preferred method for BA detection due to the complex chemical structures, the wide range of actual concentrations and the complexity of fecal sample matrices. However, free BAs are difficult to ionize, resulting in low detection signals and a lack of characteristic structural fragments to assist in structural identification. In this method, the labeling reagent (2-aminoethyl) trimethylammonium (AETMA) is employed to label the carboxyl group of BAs. Compared with underivatized BAs, the detection sensitivity of unconjugated BAs was enhanced by 25-180 fold, while that of conjugated BAs increased by 6-160 fold. It also generates unique fragment ions and enhances MS response, facilitating the discovery of potential BAs. Methodological parameters were validated using 38 BAs as representatives. Through methodological validation, it was verified that the precision, recovery, matrix effect and stability parameters of the method met acceptable criteria. We also identified 61 confirmed BAs and 55 additional candidate BAs in human pooled fecal samples. It has been successfully applied to fecal BA analysis in obese populations, providing valuable insights into potential therapeutic strategies for obesity.

Tandem Mass Spectrometry

Tranexamic acid protects human dermal fibroblasts from D-galactose-induced senescence via the GPR30/MAPK pathway.

BACKGROUND: Tranexamic acid (TXA) is widely used for pigmentary disorders, but its anti-ageing potential remains unclear. This study aimed to evaluate whether topical 3% TXA improves early periorbital wrinkles in women with facial melasma and to investigate whether TXA protects human dermal fibroblasts from D-galactose-induced senescence via the GPR30/MAPK pathway. METHODS: Fifty women with melasma were randomized to 3% TXA serum plus moisturizer or moisturizer alone for 8&#x2009;weeks, with follow-up to week 12. Periorbital wrinkles were graded using a modified Fitzpatrick Wrinkle Scale (MFWS). Separately, D-gal-induced senescence in HDFs was assessed via viability, SA-&#x3b2;-gal activity, senescence markers, ROS, antioxidant enzymes, SASP/ECM gene expression, and MAPK activation. GPR30 involvement was examined using antagonist G15, shRNA knockdown, and molecular docking. RESULTS: Topical TXA produced significantly greater MFWS reductions versus moisturizer alone at weeks 4, 8, and 12, with benefit persisting post-treatment. In HDFs, TXA preserved viability, reduced SA-&#x3b2;-gal positivity, attenuated p21/p16, restored Lamin B1, decreased ROS, and rescued antioxidant activities. TXA downregulated IL-6, IL-8, MMP1, and MMP3, and suppressed D-gal-induced ERK, JNK, and p38 phosphorylation. These effects were weakened by G15 or GPR30 knockdown; docking supported a stable TXA-GPR30 interaction. CONCLUSIONS: TXA showed clinical anti-wrinkle activity in melasma patients and protected HDFs from D-gal-induced senescence, partly via GPR30-dependent modulation of oxidative stress, SASP/ECM expression, and MAPK signalling. TXA is a promising candidate for skin ageing intervention.

Humans

Fatty acids and breast cancer: Epidemiology, subtype-specific metabolism, immune regulation, and clinical translation.

Fatty acids (FAs) are bioactive dietary and metabolic molecules that participate in membrane architecture, energy homeostasis, inflammatory signaling, gene regulation and immune function, all of which intersect with breast cancer (BC) risk, progression and treatment response. In this narrative review we integrate epidemiological, clinical, translational and mechanistic evidence on the role of FAs in BC. Saturated, monounsaturated, trans- and polyunsaturated FAs (PUFAs) are treated as distinct biological exposures rather than interchangeable measures of total fat intake. Similarly, evidence from dietary assessment, circulating biomarkers, erythrocyte membrane composition, adipose tissue stores and tumor lipid signatures is interpreted separately, because each captures exposure and biology at a different level. BC subtypes differ in FA synthesis, uptake, oxidation, storage and remodeling: luminal tumors are frequently linked to hormone-regulated lipogenesis, human epidermal growth factor receptor 2 (HER2)-positive tumors to growth-factor-driven lipid metabolism, and triple-negative tumors to exogenous FA uptake, inflammatory lipid mediators and ferroptosis-related vulnerabilities. FA-derived mediators also shape immune-cell polarization, cytokine signaling and the tumor microenvironment, and dietary FAs may reshape the gut microbiota; the fiber-derived short-chain FAs it produces, distinct from dietary FAs, likewise help regulate immune and inflammatory tone. Clinical data suggest possible roles for fat-quality modification and selected n-3 PUFA interventions, but findings are heterogeneous and not yet sufficient to support routine biomarker-guided precision onco-nutrition. Candidate biomarkers, such as erythrocyte n-6:n-3 composition, require prospective validation before clinical implementation. FA biology thus represents a modifiable but complex axis in BC prevention, tumor biology and supportive care.

Humans

Uric Acid-to-HDL Cholesterol Ratio is Associated with Hepatic Steatosis but Not Fibrosis in Nonobese Adults: A NHANES 2017-2020 Study.

BACKGROUND: Although metabolic dysfunction-associated steatotic liver disease (MASLD) has traditionally been regarded as a disease closely related to obesity, its prevalence is gradually rising in nonobese populations. The uric acid-to-high-density lipoprotein cholesterol ratio (UHR) is a novel metabolic biomarker that has been shown to be associated with MASLD. However, its role in nonobese individuals remains unclear. This study aimed to investigate the association between UHR and nonobese MASLD. METHODS: Data from the 2017 to 2020 National Health and Nutrition Examination Survey (NHANES) were analyzed. UHR was calculated as the serum uric acid (UA) divided by the high-density lipoprotein cholesterol (HDL). Liver steatosis (using controlled attenuation parameters, CAP) and fibrosis (using liver stiffness measurement, LSM) were evaluated through vibration-controlled transient elastography (VCTE). Multivariate linear regression was employed to evaluate associations. Nonlinear relationships were examined using smoothed curve fitting. RESULTS: This analysis included 3573 participants (47.41% male; aged 20-80 years). Log2-UHR was positively associated with CAP (&#x3b2; = 9.96, 95% CI: 6.93-12.98, P < 0.001) and MASLD prevalence (OR = 1.64, 95% CI: 1.38-1.95, P < 0.001). Subgroup analyses revealed significant interactions by sex, age, ethnicity, and smoking status (all P for interaction < 0.05), with stronger associations in females, adults aged 40-59 years, individuals of other Hispanic ethnicity, and never-smokers. Moreover, the association between log2-UHR and CAP was linear and positive (P < 0.01). No significant association was found between log2-UHR and LSM (P > 0.05). CONCLUSIONS: UHR is independently associated with hepatic steatosis but not fibrosis in nonobese US adults, suggesting its potential utility as an early risk assessment to tool. Large scale prospective studies are needed in the future to further validate the conclusions of this study.

Humans