Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease worldwide, encompassing a spectrum from simple steatosis to metabolic dysfunction-associated steatohepatitis (MASH), fibrosis, cirrhosis and hepatocellular carcinoma. Increasing evidence indicates that disease progression is driven not by hepatic triglyceride accumulation alone but by the metabolic partitioning of excess fatty acids between adaptive and maladaptive pathways. Ketogenesis, traditionally viewed as a fasting-induced mechanism for disposing of excess acetyl-CoA, is now recognized as a key regulator of hepatic metabolic homeostasis, coordinating mitochondrial substrate utilization, carbon flux and systemic metabolic adaptation. In addition to serving as oxidative fuels, ketone bodies, particularly β-hydroxybutyrate, function as signalling metabolites that modulate inflammation, oxidative stress, mitochondrial function and epigenetic regulation. Despite increased fatty acid delivery in obesity and insulin resistance, ketogenic capacity becomes progressively impaired during MASLD, promoting mitochondrial acetyl-CoA accumulation, oxidative stress and diversion of carbon toward lipotoxic lipid synthesis while reducing protective β-hydroxybutyrate signalling. This review examines ketogenesis as an integrative metabolic checkpoint linking fatty acid oxidation, lipid metabolism, mitochondrial function and immune signalling in MASLD. We discuss how impaired ketogenic flux contributes to hepatocellular injury, fibrosis and metabolic inflexibility, and evaluate the therapeutic potential of restoring ketogenesis to prevent disease progression.
Background: Caffeine and sodium bicarbonate (SB) are widely used ergogenic supplements that influence exercise performance through distinct physiological mechanisms and may differentially modulate exercise-related metabolic responses. Whether their co-ingestion provides benefits beyond either supplement alone remains uncertain. This study evaluated the incremental effects of caffeine and SB co-ingestion within trials specifically designed to investigate the combined supplementation strategy. Methods: A systematic review and Bayesian arm-based multilevel network meta-analysis of randomized controlled trials published up to May 2026 was conducted. Eligible studies investigated acute caffeine–SB co-supplementation and, where available, included caffeine-only and SB-only arms, with placebo as the common reference. Exercise performance was the primary outcome; blood lactate, blood pH, blood bicarbonate, and rating of perceived exertion were secondary outcomes. Effects were estimated using Hedges’ g, Bayesian credible intervals, and SUCRA rankings. Results: Thirteen studies involving 181 participants met the eligibility criteria. Within this co-supplementation trial network, caffeine (g = 0.21), SB (g = 0.21), and co-ingestion (g = 0.28) produced small but credible improvements in exercise performance relative to placebo. However, comparisons among active conditions provided no clear evidence that co-ingestion was superior to either supplement alone. SB increased blood pH (g = 0.95) and blood lactate (g = 1.13), whereas caffeine reduced blood bicarbonate (g = −0.89). Co-ingestion elicited the largest increase in blood lactate (g = 1.75), but this response was not accompanied by a proportionally greater improvement in performance. Exploratory analyses suggested possible variation in supplementation responses according to training status. Conclusions: Within trials designed to evaluate caffeine–SB co-supplementation, the caffeine-only, SB-only, and combined conditions showed small improvements in exercise performance relative to placebo. However, co-ingestion elicited more pronounced metabolic responses without a clear performance advantage over either component alone, and the mechanisms underlying this divergence remain uncertain.
Background: Traditional bulk tissue analyses obscure the precise spatial compartmentalization of nicotine and its molecular effects within individual anatomical regions. This study aimed to develop and apply a high-resolution spatial multi-omics framework to characterize the localized disposition and functional responses induced by an acute nicotine challenge. Methods: We established a spatial multi-omics framework integrating matrix-assisted laser desorption/ionization time-of-flight mass spectrometry imaging (MALDI-TOF MSI), air-flow-assisted desorption electrospray ionization mass spectrometry imaging (AFADESI-MSI), laser microdissection (LMD)-based microscale data-independent acquisition (microDIA) proteomics, and targeted LC-MS/MS. This platform was used to analyze the kidney and five brain regions in rats subjected to an acute nicotine challenge following an adaptation regimen. Results: Spatial mapping revealed distinct peripheral and central distribution patterns: nicotine, cotinine, and nornicotine accumulated predominantly in the renal cortex and medulla, whereas their distribution in the brain is region-dependent, with a prominent 3-hydroxycotinine signal in the olfactory bulb. Avoiding tissue homogenization enabled these spatial distributions to be linked to localized functional responses. The striatal dopamine/DOPAC axis showed the strongest acute neurochemical response, consistent with increased dopamine turnover. Spatial metabolomics further demonstrated robust, region-specific metabolic reprogramming, with the hippocampus showing the greatest metabolic variance. LMD-resolved proteomics identified protein-level changes, particularly in the olfactory bulb and thalamus. Cross-omics revealed coordinated alterations in purine, pyrimidine, glycerophospholipid, and alanine/aspartate/glutamate metabolism, with the thalamus showing the greatest extensive metabolite–protein concordance. Conclusions: These findings characterize acute nicotine exposure as a spatially compartmentalized process involving renal handling, region-specific brain distribution, and localized molecular response programs.
Background/Objectives: Hypothyroidism may influence lactation physiology, but evidence regarding its association with mature human milk composition remains limited. This cross-sectional study evaluated macronutrient composition and apparent thyroid-stimulating hormone (TSH) concentration in 24 h composite mature milk samples from women with a documented history/diagnosis of treated or clinically managed hypothyroidism attending lactation counseling and human milk-bank consultation, compared with controls without known thyroid disorders. Methods: Sixty-six lactating women attending the Human Milk Bank in Toruń, Poland, were enrolled (31 with hypothyroidism, including six with Hashimoto’s disease; 35 controls). Thyroid characterization was based on diagnoses and laboratory results documented during routine preconception or early-pregnancy/perinatal care; the study did not include contemporaneous maternal serum TSH/FT4 testing at milk collection in either group. Composite 24 h milk samples were analyzed using the MIRIS Human Milk Analyzer for fat, crude protein, true protein, carbohydrates, total solids, and energy. Milk TSH was measured using a third-generation ELFA assay. Because this serum/plasma assay was not formally validated for the human milk matrix, values are reported as exploratory apparent milk TSH concentrations. Results: No statistically significant between-group differences were observed in macronutrient composition in the analyses performed. For example, the HG-CG mean difference for energy content was −3.47 kcal/100 mL (95% CI: −8.45 to 1.52; p = 0.169; q = 0.814), and all confidence intervals for milk-composition outcomes included zero. Median apparent milk TSH concentration was 0.0180 [IQR 0.0130–0.0208] µIU/mL in controls and 0.0155 [IQR 0.0093–0.0210] µIU/mL in the hypothyroidism group (Mann–Whitney U = 459.0, p = 0.286). Hyperlactation was frequent in this selected cohort and was more common in controls (27/35; 77.1%) than in the hypothyroidism group (16/31; 51.6%). Exploratory analyses of pre-pregnancy BMI and Hashimoto’s disease were limited by small subgroup sizes. Conclusions: In this small selected cohort, a documented diagnosis/history of treated or clinically managed hypothyroidism was not associated with statistically significant differences in mature milk macronutrient composition or apparent milk TSH concentration. These findings are exploratory and should not be interpreted as evidence of equivalence, confirmed euthyroidism at sampling, or exclusion of smaller effects.
Background: Flavonoid secondary metabolites accumulate in xylem during heartwood formation and critically influence wood color and economic value. However, the distribution patterns of individual flavonoids across sapwood, transition zone, and heartwood remain poorly characterized in Castanopsis hystrix, limiting mechanistic understanding of heartwood formation and rational resource utilization. Methods: Sapwood, transition zone, and heartwood samples were collected and analyzed using ultra-performance liquid chromatography coupled with Q-Exactive Orbitrap mass spectrometry (UPLC-QE-MS) for qualitative and quantitative flavonoid determination. Multivariate statistical approaches, including hierarchical clustering, principal component analysis (PCA), and orthogonal partial least-squares discriminant analysis (OPLS-DA), were applied to compare regional metabolic profiles and to identify characteristic differential markers. Results: A total of 26 flavonoids were identified, covering flavones, flavonols, flavanones, dihydroflavonols, and flavanols. Quantitative and cluster analyses revealed distinct region-preferential accumulation: dihydrorobinetin, dihydromyricetin, morin, and kaempferol were highly enriched in heartwood; fustin, taxifolin, and cyanidin predominated in the transition zone, whereas afzelin and astilbin were more abundant in sapwood. PCA and OPLS-DA further selected four characteristic markers, namely dihydromyricetin, dihydrorobinetin, kaempferol and (−)-epicatechin, that effectively discriminated the three regions. Conclusions: This study establishes a clear radial gradient of flavonoid accumulation in C. hystrix xylem, demonstrating selective enrichment of specific metabolites from sapwood to heartwood. These findings provide essential data for deciphering the biochemical mechanisms of heartwood formation and offer a metabolic basis for quality assessment and high-value utilization of this timber species.
Background: For a long time, it was thought that estrogen degradation metabolites (EDMs) had no role in the female body, but this view has changed. Despite the progress, there are still unknowns about EDMs and the heart. We found that EDMs affect isolated cardiac mitochondria, which may impact heart function. Therefore, our objective was to explore the effect of two EDMs, Met A (2-hydroxyestrone) and Met D (17β-estradiol-3-methyl-ether), on two experimental models: rat H9c2 cardiomyoblast cells exposed for increasing times to different concentrations of each EDM, and, also, the effects of each metabolite on heart function in intact and oophorectomized (Oopho) rats. Methods: The cell viability, mitochondrial potential, and oxidative stress were assayed in H9c2 cells. Echocardiographic analyses, histological analyses, and an assessment of cardiac damage and oxidative stress in intact and Oopho rats were tested. Results: The strongest negative effects were seen with Met D, where antioxidant capacity decreased and oxidative stress increased significantly. Upon further analysis of the effects of each metabolite on heart function, echocardiographic analysis revealed that cardiac function had not changed in either group, although clear signs of cardiac hypertrophy and fibrosis were observed. Conclusions: Our results suggest EDMs have specific effects on female rats. This study emphasizes the need to thoroughly investigate EDMs’ side effects and impact on the heart.
Background: This cross-sectional study compared immunoassay urine drug screening with LC–MS/MS confirmation in individuals with substance use disorder undergoing probation monitoring, focusing on samples with results close to assay cutoff values. Methods: The study was conducted between January and March 2026 in Şanlıurfa, Türkiye, and included 110 individuals followed at an Addiction Treatment Center (AMATEM). Urine samples with at least one analyte result within ±20% of the cutoff value were analyzed. Immunoassay screening was performed using a Beckman Coulter AU480 analyzer, whereas confirmation was performed by LC–MS/MS using a SCIEX Triple Quad 5500+ system. Agreement was evaluated using Cohen’s kappa and McNemar’s test, while diagnostic performance was assessed using 2 × 2 contingency tables. Results: Agreement varied substantially among analyte groups. Buprenorphine showed the highest agreement (κ = 0.47), followed by amphetamines (κ = 0.33), whereas opioids showed very low agreement (κ = 0.081). Benzodiazepines, cocaine, and cannabinoids showed no meaningful agreement; however, benzodiazepine and cocaine findings were limited by very low numbers of positive cases. Immunoassay screening produced notable false-positive results for amphetamines and opioids and false-negative results for cannabinoids and opioids. Conclusions: Immunoassay performance was analyte-dependent and appeared limited in samples with results close to cutoff values. LC–MS/MS confirmation remains important for reliable toxicological interpretation in probation monitoring settings.
Background: Myelodysplastic neoplasms (MDSs) are clonal hematopoietic stem cell disorders associated with ineffective hematopoiesis, chronic inflammation, and increased cardiovascular morbidity. Although metabolic dysregulation has been implicated in MDS pathogenesis, systemic metabolic alterations remain incompletely characterized. Methods: Plasma samples from treatment-naïve patients with MDS or chronic myelomonocytic leukemia (CMML) and age-matched healthy controls were analyzed using quantitative nuclear magnetic resonance spectroscopy and liquid chromatography-mass spectrometry (LC-MS). Metabolomic profiles were compared using unsupervised and supervised multivariate analyses, validated in an independent external MDS cohort, and integrated with re-analysis of publicly available RNA-sequencing datasets from purified CD14+ CMML monocytes. Results: Patients with MDS and CMML exhibited broad reductions in circulating lipoprotein-associated metabolites, including HDL-, LDL-, IDL-, and apolipoprotein-associated fractions, indicating disturbed systemic lipoprotein homeostasis. Within the discovery cohort, CMML samples showed higher concentrations of the ketone bodies 3-hydroxybutyrate and acetoacetate, as well as succinate. LC-MS analysis demonstrated selective increases in C18:1 acylcarnitine, oleic and isopalmitic acids, whereas free carnitine abundance remained unchanged. Elevated 3-hydroxybutyrate levels were not associated with mutational burden, hematologic parameters, disease risk, or immunophenotypic features. Re-analysis of public CMML monocyte transcriptomes demonstrated increased expression of genes involved in lipid uptake and intracellular lipid trafficking, including FABP5, APOE, LPL, and SLC27A2, without coordinated activation of fatty acid oxidation pathways. External cohort analysis confirmed the overall MDS-associated plasma metabolomic profile. Conclusions: MDSs and CMML are associated with reproducible alterations in systemic lipid metabolism characterized by reduced circulating lipoprotein-associated metabolites, while CMML showed more pronounced ketone body- and acylcarnitine-associated metabolic phenotype accompanied by changes in lipid-handling transcriptional programs. These findings support altered systemic lipid metabolism and carnitine-dependent fatty acid handling as characteristic features of myeloid neoplasms and provide a rationale for future functional studies investigating lipid metabolism in disease pathogenesis.
Background: Intramuscular fat (IMF) is a key determinant of meat sensory quality, but the effects of rumen-protected betaine (RPB) on IMF deposition in Tibetan sheep remain unclear. Methods: Sixty male, 3-month-old Tibetan lambs (Initial weight 17.72 ± 1.36 kg) were randomly assigned to a control (basal diet, n = 30) or RPB supplementation (basal diet supplemented with 0.08% RPB, n = 30) for 90 d. Results: Transcriptomic and lipidomic analyses revealed that RPB modulated glycerophospholipid metabolism-related genes (DGKI and AGPAT1) and altered lipid profiles, including PC (16:0/20:5) and PC (16:0/16:0). RPB increased T-AOC and SOD activities and decreased MDA content (p < 0.05). Intramuscular adipocyte area and diameter increased, while density decreased (p < 0.05). LC-MS/MS analysis showed that unsaturated fatty acids C14:1, C17:1, and C22:4 were significantly increased (p < 0.05). Muscle fiber density in the longissimus dorsi increased, whereas shear force, cooking loss, hardness, and chewiness were reduced (p < 0.05). MYH1, MYH2, and MYH7 expression were upregulated by 2.05-, 1.89-, and 2.73-fold, respectively. Conclusions: In summary, dietary RPB supplementation was associated with increased IMF deposition, which may contribute to improved meat quality, potentially through modulation of glycerophospholipid metabolism.
Objective: Saline–alkali stress (composed of neutral and alkaline salts) severely constrains soybean productivity. Although nicotinamide can enhance plant salt tolerance, its most effective concentration and molecular basis in soybean remain unclear. This study aimed to systematically investigate the regulatory effect of exogenous nicotinamide on soybean saline–alkaline tolerance and to identify its candidate genes and putative mechanisms under salt-stressed conditions. Methods: Soybean cultivar ‘Hefeng 25’ seedlings were exposed to 200 mmol/L mixed salt stress and treated with nicotinamide at 0 (CK), 10, 50, and 200 mg/L. Growth parameters, ROS levels, ion contents, photosynthetic pigments, osmoregulatory substances, and antioxidant enzyme activities were measured. Transcriptome sequencing and RT-qPCR were performed to identify differentially expressed genes (DEGs), followed by enrichment analysis. Results: Exogenous nicotinamide significantly improved soybean saline–alkaline tolerance relative to the salt-stressed CK group, with 50 mg/L (SA2) showing the most pronounced physiological improvements among all tested concentrations. SA2 treatment enhanced plant height, biomass, K+ content, and antioxidant enzyme activities while reducing Na+ accumulation and ROS levels compared with CK. Transcriptome analysis identified PM1 as the shared gene across the five non-most effective comparisons. Enrichment analysis implicated DEGs primarily in ko03110 (chaperones and folding catalysts), ko00199 (cytochrome P450), and ko04141 (protein processing in the endoplasmic reticulum). RT-qPCR confirmed that PM1, P450 genes (CYP74A1, CYP83D1), HSPs (HSP23, HSP18), and ROS scavengers (NAC1, GSTU43) were upregulated under non-most effective doses (SA1/SA3) but downregulated to levels comparable to the stressed CK in SA2; conversely, SA2 specifically restored the expression levels of stress-repressed WRKY57 and LBD15. Transcriptomically, SA2 exhibited a profile most similar to the saline–alkali-stressed CK group, with the fewest number of differentially expressed genes among all treatments, whereas non-optimal nicotinamide concentrations were associated with extensive transcriptional changes in ER protein processing, detoxification-related, and oxidative stress-related pathways. The limited transcriptional changes in SA2 indicate greater transcriptional similarity to the stressed control, which paralleled its superior physiological performance. Conclusions: Nicotinamide effectively alleviates soybean saline–alkaline stress at 50 mg/L, with the most significant physiological benefits and the fewest transcriptional changes relative to the stressed control. The non-most effective nicotinamide concentrations show extensive stress-related transcriptional reprogramming in protein folding, detoxification, and stress-response pathways relative to the salt-stressed control, putatively implicating ER stress, detoxification, and oxidative stress-related responses at the transcript level, with PM1 acting as a potential candidate transcriptional marker of dose-dependent transcriptional regulation under saline–alkali stress.
Background: Metabolic complications and weight gain have emerged as primary concerns among virologically suppressed and immunologically competent people living with HIV. Particularly integrase strand transfer inhibitors (INSTIs) and tenofovir alafenamide (TAF) are being connected with this issue. Objectives: This study aimed to evaluate the prevalence of metabolic syndrome (MetS) and its components within a highly homogeneous, virologically suppressed cohort, assessing the impact of antiretroviral therapy (ART) and HIV-unrelated factors. Methods: We conducted a single-center cross-sectional analysis of 93 HIV-positive patients receiving stable ART for >2 years, in Wrocław, Poland. To minimize confounding, individuals with HBV/HCV co-infections or significant alcohol use were excluded. Participants were stratified primarily by regimen, INSTI/TAF-based (n = 50) vs. PI/TAF-based (n = 28), and secondarily by the particular drugs taken. Clinical assessment included anthropometric parameters, lipid profiles, and glucose metabolism. Results: The prevalence of MetS was 10.8%. No statistically significant differences were observed in the incidence of MetS, insulin resistance, or dyslipidemia between the INSTI/TAF and PI/TAF groups. A marginally significant trend toward lower total cholesterol was identified in patients receiving dolutegravir/TAF compared to those on darunavir/TAF. Conclusions: In this stable Caucasian cohort with long-term viral suppression, we found no statistically significant differences in metabolic outcomes between modern INSTI- and PI-based regimens. However, due to the limited sample size and low statistical power, these findings do not prove clinical equivalence. Our results suggest that in particular tightly selected settings of well-controlled patients, traditional risk factors and lifestyle may remain the primary drivers of metabolic health, although modest drug-related effects cannot be ruled out.
Background: Oxidative stress, neuroinflammation, impaired autophagy, and mitochondrial dysfunction are major contributors to ageing and neurodegenerative diseases. This study investigated whether AgeViva could counteract these processes by modulating redox balance, inflammation, autophagy, and mitochondrial function. Methods: The effects of AgeViva were evaluated using two complementary experimental models: lipopolysaccharide (LPS)-stimulated BV2 microglial cells and Caenorhabditis elegans (C. elegans) nematodes. In BV2 cells, the expression of inflammatory, autophagy-related, and antioxidant response genes, including NRF2, SOD, and GPX, was evaluated by RT-qPCR, while cell viability was assessed by Trypan Blue exclusion assay. In C. elegans, lifespan, healthspan parameters, ROS accumulation, mitochondrial integrity, membrane potential, and the expression of stress-response, longevity, and autophagy-related genes were analyzed following AgeViva supplementation. Results: In LPS-stimulated BV2 cells, AgeViva significantly reduced the expression of mRNA the pro-inflammatory cytokines Interleukin-1 beta (IL-1β) and Tumor Necrosis Factor alpha (TNF-α) while increasing Interleukin-10 (IL-10) levels, AgeViva also induced changes in autophagy-related transcripts, such as modulation of microtubule-associated protein 1a/1b-Light Chain (LC3) and Sequestosome 1 (p62) expression, activated antioxidant-related gene expression, increasing the expression of Superoxide Dismutase 1(SOD1) and Glutathione Peroxidase (GPX). In C. elegans, AgeViva supplementation extended lifespan and improved healthspan parameters, including locomotor activity and pharyngeal pumping. Treated nematodes showed reduced cytosolic and mitochondrial ROS accumulation, preservation of mitochondrial network integrity, and maintenance of mitochondrial-associated fluorescence, reflecting mitochondrial content and/or membrane potential during ageing. Molecular analyses revealed modulation of key pathways involved in stress resistance and longevity, including Insulin-like Growth Factor 1 (Insulin/IGF-1) signaling Dauer Formation-2 and 16 (DAF-2/DAF-16), Skinhead-1 (SKN-1/Nrf2) signaling, and autophagy-related genes, like Ligating (lgg-1), Autophagy-Related-7 (atg-7), Autophagy Related-18 (atg-18), uncoordinated-51 (unc-51), and ectopic p-granules autophagy protein 5 (epg-5). Conclusions: AgeViva promotes healthy ageing by modulating oxidative stress, inflammation, autophagy, and mitochondrial homeostasis.
Gut microbial metabolism links intestinal ecology with systemic physiology and neural pathology, but its effects vary across disease stage, tissue compartment, and host background. This review uses Alzheimer’s disease (AD) as the principal model and compares selected features with Parkinson’s disease (PD) and amyotrophic lateral sclerosis (ALS). Across the AD continuum, fermentation-related changes appear in prodromal cohorts, whereas broader alterations in amino acid products, host–microbial co-metabolites, bile acids, and lipids accompany mild cognitive impairment and dementia. These group-level patterns do not constitute a fixed patient trajectory. Microbial production, intestinal absorption, hepatic conversion, renal clearance, barrier integrity, and tissue-specific receptors jointly determine biological exposure. Experimental studies connect short-chain fatty acids and indole derivatives with epithelial and neuroimmune homeostasis, while imidazole propionate, trimethylamine N-oxide, selected kynurenine products, and remodeled bile acid pools engage vascular, inflammatory, amyloid, or tau-related pathways. Cerebral pathology can also remodel the intestinal ecosystem, creating reciprocal feedback. Apolipoprotein E4 modifies lipid handling, vascular permeability, and immune responses, helping to explain why comparable metabolic profiles may carry different consequences among individuals. Translation therefore requires more than a change in community composition. Trials must verify microbial function, metabolite target engagement, AD biomarker response, and clinical benefit in appropriately stratified participants. Shared pathways in PD and ALS provide comparison points, but disease-specific cells, proteinopathies, and treatment exposures constrain direct transfer of AD-derived targets.
Background/Objectives: House dust mites (HDMs) are significant allergens that cause damage to nasal epithelial cells and have a role in the pathophysiology of allergic rhinitis. Lactobacillus johnsonii N5 supernatant (N5sup), a probiotic strain, exhibits possible protective properties; nevertheless, the molecular processes involved remain unclear. Methods: RPMI-2650 human nasal epithelial carcinoma cells were subjected to treatment with HDM, N5sup, or a combination of both. Results: The HDM stimulation induced a certain degree of transcriptional alterations. Compared with the control group, a total of 221 differentially expressed genes were identified in HDM-treated cells, which were mainly enriched in the IRE1–XBP1 branch of the unfolded protein response (UPR) pathway. Comprehensive investigation demonstrated that HDM increased the NR4A1–IRE1–XBP1 signaling pathway, characterized by elevated expression levels of NR4A1, ERN1 (IRE1), and XBP1. Both qRT-PCR and Western blotting verified that N5sup strongly inhibited the HDM-induced increase in NR4A1, IRE1, and XBP1. Analysis of the protein–protein interaction network further confirmed a central hub comprising NR4A1, IRE1, and XBP1. Conclusions: N5sup supernatant protects RPMI-2650 cells from HDM-induced injury, and this protective effect is associated with the NR4A1–IRE1–XBP1 pathway. These findings suggest that this signaling axis may serve as a potential therapeutic target for probiotic intervention in allergic airway diseases.
Nicotinamide adenine dinucleotide (NAD+) is a fundamental metabolic cofactor and signaling molecule that supports redox reactions, DNA repair, chromatin regulation, stress adaptation, inflammation, and neuronal maintenance. Age-associated NAD+ decline has been implicated in brain aging and neurodegenerative disorders, but the causal node and limiting compartment differ across tissues and disease states. Nicotinamide mononucleotide adenylyltransferase 1 (NMNAT-1) catalyzes the final step in NAD+ biosynthesis and represents the major nuclear isoform of the mammalian NMNAT family. Direct human genetic evidence establishes NMNAT-1 as a causal gene in inherited retinal degeneration, whereas evidence linking endogenous NMNAT-1 to broader brain aging or sporadic neurodegeneration is mainly convergent preclinical, preliminary, or indirect. Beyond NAD+ synthesis, biochemical and Drosophila studies suggest possible chaperone-like and proteostasis-supporting functions, but a separable NAD+-independent function of endogenous mammalian NMNAT-1 has not yet been established in vivo. Here, we review the molecular structure, localization, and regulation of NMNAT-1, emphasizing calibrated distinctions among catalytic nuclear NAD+ supply, engineered axonal protection, pathway-adjacent NAD+ interventions, and putative non-catalytic protection. We further discuss how NMNAT-1 dysfunction may contribute to aging-associated genomic instability, neuroinflammation, synaptic impairment, retinal degeneration, selected neurodegenerative models, and glioma biology. Finally, we evaluate therapeutic strategies targeting NMNAT-1 and NAD+ pathways, noting that no human trial has yet established efficacy for an NMNAT-1-directed neurological therapy. A compartment-aware and evidence-stratified view is therefore essential for translating NMNAT-1 biology into interventions for age-related neural disease.
Background/Objectives: Inflammatory bowel disease (IBD) is a chronic gastrointestinal disorder influenced by environmental factors including cold stress. While cold exposure exacerbates intestinal inflammation, the specific microbial metabolites linking environmental stress to colitis remain unclear. 3-Hydroxypropionate (3-HPA) is a gut microbial metabolite elevated following cold exposure, but its pathogenic role in intestinal inflammation has not been investigated. This study aimed to determine whether 3-HPA contributes to colitis progression and to characterize its effects on gut microbiota and intestinal epithelial function. Methods: We employed a dextran sulfate sodium (DSS)-induced colitis mouse model to assess the impact of cold exposure and exogenous 3-HPA administration. Paired shotgun metagenomic and metabolomic analyses were performed to evaluate gut microbial composition and metabolic outputs. Mechanistic studies using NCM460 intestinal epithelial cells were conducted to examine mitochondrial respiration and tight junction integrity under nutrient-limited conditions. Results: Cold exposure increased fecal 3-HPA levels and aggravated DSS-induced colitis, characterized by enhanced weight loss, histological damage, and immune cell infiltration. Direct 3-HPA supplementation alone was sufficient to worsen colitis severity. Multi-omics profiling revealed that 3-HPA reshaped gut microbiota composition, depleted short-chain fatty acids (SCFAs), and disrupted microbial tryptophan and bile acid metabolism. In vitro, 3-HPA impaired mitochondrial oxidative phosphorylation, reduced ATP production, and compromised tight junction organization in intestinal epithelial cells. Conclusions: These findings identify 3-HPA as a gut microbial metabolite elevated by cold exposure that contributes to colitis progression by disrupting beneficial microbial metabolism while also impairing epithelial mitochondrial function and barrier integrity. Modulating 3-HPA production or its downstream epithelial effects may represent a potential therapeutic approach for IBD exacerbated by environmental stress.
Background/Objective: Maternal diet is an important determinant of gut microbiota composition in dams and offspring. This study investigated whether HDCA supplementation during maternal high-fat diet (HFD) exposure was associated with gut microbiota composition in dams and offspring and with selected obesity-related phenotypes. Methods: Nineteen C57BL/6J female mice were assigned to a control diet group (CON), a high-fat diet group (HFD), and a high-fat diet supplemented with 0.5% hyodeoxycholic acid group (HFD+HDCA). Fecal samples were collected from the dams before mating, following 8 weeks of dietary intervention, and from the offspring at weaning. All samples were analyzed using 5R 16S rRNA gene sequencing. Body weight was monitored in both dams and offspring, and liver histology was assessed by hematoxylin and eosin staining. Results: HFD exposure was associated with obesity-related phenotypes in dams and offspring, including increased maternal body weight and greater hepatic lipid accumulation and visceral adiposity in offspring. LEfSe and ANCOM-BC2 analyses identified concordant microbial changes between dams and offspring under corresponding dietary conditions. Lachnospiraceae_Unknown_genus3261 and Coprococcus increased with HFD exposure in both dams and offspring, whereas Bifidobacterium, Coprococcus, and Allobaculum decreased following HDCA supplementation. These findings indicate maternal–offspring concordance in microbiota responses to HFD and HDCA, without establishing direct vertical transmission. PICRUSt2 analysis suggested group association differences in predicted functional potential for pathways annotated to propionate, pyruvate, and β-alanine metabolism. Conclusions: HDCA supplementation during maternal HFD exposure was associated with differences in offspring gut microbiota at weaning and with attenuation of selected obesity-related phenotypes. These findings suggest a potential role of the gut microbiota–bile acid axis in mediating intergenerational dietary effects. However, the study does not establish direct microbial transmission, altered metabolic activity, or causality; these findings require confirmation in litter-aware and mechanistic studies.
Background: Recovering from COVID-19 does not always lead to complete recovery, and many patients report symptoms of anxiety and depression. One potential mechanism behind these disorders is dysbiosis. The aim of this study was to evaluate the impact of psychobiotic therapy on the effectiveness of treating anxiety and depressive symptoms in individuals who had previously experienced COVID-19. Methods: This study was designed as a randomized, double-blind, placebo-controlled trial. A total of 62 participants were randomly allocated to one of two groups: a psychobiotic group (PG; 23 women, 9 men) receiving 3 × 109 CFU Lactobacillus helveticus and Bifidobacterium longum, or a control group (CG; 21 women, 9 men) receiving a placebo, for 6 weeks. Fifty-six participants finalized the study and were included in the analysis (28 per group). The severity of depressive and anxiety symptoms at baseline and after the intervention was assessed using validated self-assessment tools: the Hospital Anxiety and Depression Scale (HADS), the Generalized Anxiety Disorder 7-item scale (GAD-7), the Beck Depression Inventory (BDI), and the Hopkins Symptom Checklist (SCL-90). Additionally, the profile of selected short-chain fatty acids (SCFAs) in the stool was assessed. Results: Following the supplementation period, the PG showed significantly lower median levels of depression and anxiety compared to the CG, corresponding to a 57.2% reduction in anxiety severity (GAD-7) and a 50.9% reduction in depressive symptoms (BDI) (HADS—Depression and Anxiety, and GAD-7: p = 0.0001; BDI: p = 0.0003). Additionally, the prevalence of anxiety and depressive symptoms significantly decreased in the PG compared to the CG based on the HADS-A (p = 0.0044), GAD-7 (p = 0.0219), and BDI (p = 0.0011) scores. Among the measured SCFAs, only the butyric acid concentration in PG increased significantly during supplementation (baseline vs. follow-up—p = 0.0338) and was higher in PG than in CG at the study’s end (p = 0.0248). However, in the PG, changes in the concentrations of all analyzed acids correlated with a reduction in the severity of anxiety symptoms measured using the HADS-A. Conclusions: Psychobiotic supplementation in individuals recovering from COVID-19 who exhibit anxiety and/or depressive symptoms led to mood improvement and a reduction in symptom severity, and it may serve as a supportive treatment.
Background: AML cells can be defined by impairments in glycolytic metabolism, resulting in increased glucose uptake coupled with reduced glycolytic flux. Consequently, cells rely on alternative pathways such as glutamine metabolism to fuel mitochondrial respiration through anapleurosis. AML cells express upregulated levels of glutamine transporters and catabolic enzymes such as solute carrier family 1 member 5 (SLC1A5) and glutaminase 1 (GLS-1), respectively, to support metabolic needs; impairment of glutamine metabolism induces proliferative arrest. Our previous work identified plumbagin (PLB) as a selective activator of pyruvate kinase isoform M2 (PKM2), resulting in increased PKM2 tetrameric protein, impaired PKM2 nuclear translocation and suppressed c-Myc expression. Objective: Therefore, we aimed to investigate whether PLB-mediated PKM2 activation influences glutamine metabolism as a downstream effect of c-Myc suppression in AML. Methods/Results: AML cell lines treated with PLB were cultured in the presence or absence of glutamine and were compared to cell models with genetically suppressed PKM2 to assess for differences in growth. Spectrophotometric analysis revealed that PLB treatment reduces intracellular glutamine uptake, and immunoblotting indicated suppression of GLS-1 expression, ultimately leading to reduced AML cell proliferation and viability. Supplementation with glutamine partially restored cell growth, indicating that PKM2 modulation is associated with impaired glutamine uptake and utilization. Conclusion: Overall, this study explores the downstream implications of PLB-induced alterations in the c-Myc/PKM2 axis, expanding the understanding of PKM2’s function beyond glycolysis. The findings presented confirm that PKM2 activation leads to indirect consequences on glutamine metabolism in AML, providing further insight into the mechanisms of PLB-mediated AML cell death.
Background/Objectives: Dietary inflammation may influence cardiometabolic health, yet the gut mycobiome and bacterial–fungal interactions remain unclear. Building upon our earlier findings and data from the TALENTs trial (Targeting Aging and Longevity with Exogenous Nucleotides) baseline data, we explored gut fungal profiles and bacterial–fungal co-occurrence patterns in relation to the Dietary Inflammatory Index (DII) and Life’s Essential 8 (LE8) in older adults. Methods: We enrolled 301 community residents aged 60–70 years, with 285 providing qualified fungal internal transcribed spacer (ITS) sequencing data. DII scores were derived from 3-day dietary records to reflect dietary inflammatory risk, and LE8 (integrating health behaviors including physical activity and metabolic health factors including BMI, blood lipids, blood pressure, and blood glucose) was used to assess cardiovascular health; LE8_non-diet was applied as a sensitivity measure. Fungal diversity, genus-level taxa, ecological guilds, and bacterial–fungal associations were analyzed using diversity indices, ZINB/Hurdle models, bootstrap, E-values, DIABLO analysis, and network construction. Results: DII showed an inverse correlation with LE8_non-diet (r = −0.130, p = 0.024). Fungal alpha and beta diversity did not differ significantly across DII-defined groups. Conversely, better cardiovascular status was linked to higher fungal richness, with significantly elevated Chao1 and ACE indices in the high-CVH group (both p < 0.05). Additionally, integrated ZINB, Hurdle, and stability analyses jointly pinpointed four candidate fungal genera that correlated with both DII and LE8. Both ZINB and DIABLO analyses consistently indicated that antagonistic interactions dominated gut bacterial–fungal associations (89.9% vs. 63.8% of negative associations, respectively), with DIABLO further revealing synchronized community-level co-variation between the two kingdoms (r = 0.325, p < 0.01). FUNGuild prediction further revealed saprotrophic guilds enriched in the high-CVH group and host-associated guilds in the low-CVH group, with similar patterns across DII-defined groups. Conclusions: This cross-sectional study reveals gut mycobiome profiles and potential bacterial–fungal co-occurrence patterns among older adults stratified by dietary inflammatory potential and cardiovascular health status, generating testable hypotheses for subsequent nutritional and metabolic research integrating lifestyle behaviors and functional health outcomes.
