Search Results (360)

While the Ankom RF system facilitates efficient high-throughput in vitro fermentation studies, its high cost and limited flexibility constrain its broader applicability. To address these limitations, we developed and validated a low-cost, modular gas monitoring system (FerME), assembled from commercially available components. To evaluate its performance and reproducibility relative to the Ankom RF system (Ankom Technology, Macedon, NY, USA), in vitro rumen fermentation experiments were conducted under strictly controlled and identical conditions. Whole rumen contents were collected approximately 2 h post-feeding from individual mid- or late-lactation dairy cows and immediately transported to the laboratory. Each fermenter received 50 mL of processed rumen fluid, 100 mL of anaerobically prepared artificial saliva buffer, and 1.2 g of the donor cow’s diet. Bottles were sealed with the respective system’s pressure sensors, flushed with CO₂, and incubated in a 50 L water bath maintained at 39 °C. FerME (New Taipei City, Taiwan) and Ankom RF fermenters were placed side-by-side to ensure uniform thermal conditions. To assess the effect of filter bag use, an additional trial employed Ankom F57 filter bags (Ankom Technology, Macedon, NY, USA; 25 μm pore size). Trial 1 revealed no significant differences in cumulative gas production, volatile fatty acids (VFAs), NH₃-N, or pH between systems (p > 0.05). However, the use of filter bags reduced gas output and increased propionate concentrations (p < 0.05). Trial 2, which employed filter bags in both systems, confirmed comparable results, with the FerME system demonstrating improved precision (CV: 4.8% vs. 13.2%). Gas composition (CH₄ + CO₂: 76–82%) and fermentation parameters remained consistent across systems (p > 0.05). Importantly, with 12 pressure sensors, the total cost of FerME was about half that of the Ankom RF system. Collectively, these findings demonstrate that FerME is a reliable, low-cost alternative for real-time rumen fermentation monitoring and could be suitable for studies in animal nutrition, methane mitigation, and related applications. Full article

Lactate, once regarded as a metabolic byproduct, is now recognized as a critical immunometabolic regulator that shapes immune responses in both physiological and pathological contexts. This review examines how lactate accumulation occurs across diverse disease settings, including cancer, sepsis, and diabetes, through mechanisms such as hypoxia, mitochondrial dysfunction, and pharmacologic intervention. We then explore how lactate modulates immunity via four integrated mechanisms: transporter-mediated flux, receptor signaling (e.g., GPR81), context-dependent metabolic rewiring, and histone/protein lactylation. Particular emphasis is placed on the dichotomous effects of endogenous versus exogenous lactate, with the former supporting glycolytic effector functions and the latter reprogramming immune cells toward regulatory phenotypes via redox shifts and epigenetic remodeling. The review also highlights how the directionality of lactate transport, and the metabolic readiness of the cell determine, whether lactate sustains inflammation or promotes resolution. After analyzing emerging data across immune cell subsets and disease contexts, we propose that lactate serves as a dynamic rheostat that integrates environmental cues with intracellular metabolic and epigenetic programming. Understanding these context-dependent mechanisms is essential for the rational design of lactate-targeted immunotherapies that aim to modulate immune responses without disrupting systemic homeostasis. Full article

Background/Objectives: Breast milk provides essential nutrition and immune protection to support infant growth and development. However, insufficient breast milk remains a serious issue, and bioactive peptides represent a potential strategy to promote lactation. In this study, we investigated the impact of a methionine-containing dipeptide, EM, on MCF-10A mammary epithelial cells. Methods: MCF-10A cells were treated with EM, and cell proliferation and the expression of key milk protein genes were assessed. Integrated transcriptomic and untargeted metabolomic analyses were performed to identify EM-induced changes in metabolic and gene expression pathways. Results: EM treatment significantly enhanced cell proliferation and upregulated the expression of key milk protein genes (CSN1S1 (casein alpha-S1, encoding alpha-S1 casein), CSN2 (casein beta, encoding beta-casein), and CSN3 (casein kappa, encoding kappa-casein)) at both transcriptional and protein levels compared to controls. Integrated transcriptomic and metabolomic analyses revealed that EM reprogrammed amino acid metabolism, lipid biosynthesis, and nutrient transport pathways. Core genes such as SLC7A11, APOE, and ABCA1 were identified as critical nodes linking metabolic and transcriptional networks. Conclusions: These findings indicate that EM may promote lactogenic activity by modulating metabolic and transcriptional networks in vitro, highlighting the potential of dipeptide-based nutritional interventions, which warrants further in vivo validation. Full article

A periplasmic D-malate:cytochrome c oxidoreductase (DMCO) was identified in Ectopseudomonas oleovorans CECT5344, utilizing 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-phenyl tetrazolium chloride (INT) as an artificial electron acceptor. The assay was adapted for a spectrophotometric or native polyacrylamide gel electrophoresis (PAGE) analysis. The DMCO-encoding gene (BN5_4044) was cloned and expressed in Escherichia coli, enabling a partial purification and biochemical characterization. In addition to D-malate, the enzyme oxidizes D-2-hydroxyglutarate and, to a lesser extent, D-lactate, with cytochrome c also serving as an electron acceptor. DMCO requires Zn²⁺ for activity and exists as a dimer, as determined by gel filtration. The in vitro reconstitution of the electron transfer from D-malate to oxygen was achieved using spheroplasts, enriched periplasmic fractions, and cytochrome c. This extracytoplasmic respiration, unique among homologs of this protein, may eliminate the need for a dedicated inner membrane transporter, thereby avoiding potential upstream respiratory bottlenecks. In the context of bioremediation, and particularly regarding the cyanide metabolism, this D-malate oxidation to oxaloacetate facilitates detoxification by forming the corresponding cyanohydrin, which can be subsequently assimilated for growth. Full article

Background: Recurrent vomiting in infantile hypertrophic pyloric stenosis (IHPS) leads to metabolic alkalosis and a respiratory-driven compensatory hypercapnia. Alkalosis has been identified as the main causal factor for respiratory depression on admission. The value of contribution of hemoglobin and carbon dioxide partial pressure to this phenomenon will be evaluated. Materials and Methods: A retrospective cohort study was conducted on 105 infants with IHPS. The acid/base status, including levels of hemoglobin and lactate, were recorded. Statistical comparisons, correlation analysis, linear regression and multivariate regression analysis were applied. Results: Hypercapnia was associated with hemoconcentration. We found a positive correlation was found between pCO₂ and hemoglobin (p = 0.042). The multivariate linear regression analysis showed that pCO₂ is dependent on hemoglobin (p = 0.002). Lactate, which is used as a marker for anaerobic glycolysis, showed no systematic correlation with pCO₂. Conclusions: An increase in carbon dioxide cannot easily be attributed to a reduced transport function of carbon dioxide due to hemoglobin deficiency. Further investigation is needed to determine the extent to which low hemoglobin levels and increased pCO₂ interact with hemoconcentration to contribute to respiratory problems. Full article

This study aims to investigate the effects of dietary proanthocyanidins (PACs) on growth performance, intestinal inflammation and barrier function, and bile acid metabolism-related genes in weaned piglets challenged with lipopolysaccharide (LPS). A total of 18 21-day-old castrated piglets (7.16 ± 1.66 kg) were randomly assigned to three groups: (1) CON (a basal diet), (2) LPS (a basal diet + LPS), (3) LPS + PAC (a basal diet + LPS + 250 mg/kg PAC), with each group consisting of six replicates of 1 piglet per treatment. The study lasted for 21 days. On the 14th and 21st days of the experiment, piglets in the LPS and LPS + PAC groups received an intraperitoneal injection of 100 µg/kg body weight of LPS, while the piglets in the CON group received an injection of 0.9% normal saline solution. The LPS + PAC group exhibited a significantly higher average daily gain (ADG) than the LPS group (p < 0.05). LPS stimulation resulted in a decreased (p < 0.05) villus height of the jejunum and ileum and an increased number of goblet cells. These effects were alleviated (p < 0.05) in the LPS + PAC group. The LPS + PAC group decreased the level of TNF-α and D-lactate in serum and the gene expression of IL-6 and IL-1β in the ileal tissue, compared with the LPS group, while increasing the gene expression of Occludin and ZO-1 in the ileal tissue (p < 0.05). LPS stimulation down-regulated the expression of genes regulating bile acid synthesis and transport, including hepatic CYP7A1 and ileum ASBT, whereas dietary PAC had no significant effect on the expression of these genes (p > 0.05). Nevertheless, supplementation with PAC significantly increased the expression levels of GLP-2R, GCG, and TGR5 in the ileum of piglets (p < 0.05). Additionally, piglets in the LPS + PAC group exhibited a significant increase in the level of glucagon-like peptide 2 (GLP-2) compared with the LPS group (p < 0.05). PAC generally improves the ADG, intestinal morphology, and intestinal barrier function of piglets by activating TGR5 to stimulate the intestinal secretion of GLP-2. Full article

The SLC4A11 gene encodes a membrane transporter implicated in congenital hereditary endothelial dystrophy, Harboyan syndrome, and certain cancers. Despite its clinical importance, current data on SLC4A11 expression patterns, transcript variants, and functional roles remain inconsistent and sometimes contradictory. We have systematized existing data, identified areas of consensus, and highlighted discrepancies. This review addresses SLC4A11 transcript and isoform diversity and how this complexity influences both the interpretation of its tissue expression patterns (particularly in the corneal endothelium) and the investigation of its functional roles in health and disease. Our review also untangles the evolving understanding of SLC4A11 function, from its initial classification as a bicarbonate transporter to its established roles in NH₃- and pH-regulated H⁺/OH⁻ transport, lactate efflux, cellular stress responses, and adhesion. The review details how pathogenic mutations disrupt protein maturation, membrane localization, or transport activity, contributing to corneal fluid imbalance and disease. We also discuss the emerging role of SLC4A11 in cancer metabolism and the common metabolic features of dystrophic corneas and tumors. Methodological challenges are appraised, encouraging caution in interpretation and the need for isoform-specific studies. Overall, this review provides a comprehensive update on SLC4A11 biology and identifies key gaps for future research. Full article

The present study investigated the influence of a 30 day exposure of rainbow trout (Oncorhynchus mykiss) to a suboptimal low temperature of 1.8 ± 1.0 °C on their different gill characteristics (morphometry, enzyme activities, and expression of genes) in comparison to fish acclimated to 9.4 ± 0.1 °C. Morphometric analysis revealed a significant decrease in the distance between the secondary lamellae at the low temperature, which can be interpreted as a decrease in the effective gill surface. The epithelial thickness increased at the lower temperatures, which is considered a mechanism to reduce ion fluxes and save the energy costs for osmoregulation. The length of the primary lamellae, distance between the primary lamellae, length of the secondary lamellae, as well as the number of mucus cells, chloride cells, and capillaries per mm of the secondary lamella were similar between the temperature regimes. The enzymatic activities of pyruvate kinase and malate dehydrogenase were significantly increased in cold-exposed fish, whereas lactate dehydrogenase activity was higher in controls, indicating increased energy expenditure and adjustments in energy metabolism. The activities of carbonic anhydrase, caspase, Na⁺/K⁺ ATPase, and H⁺ ATPase, and the gene expressions of hif1a, ca2, rhCG, slc26a6, and slc9a1 showed no statistically significant differences between the two temperature regimes. Therefore, it can be concluded that ammonia transport, acid–base regulation, and osmoregulation were not affected by the tested low temperature regime. These findings highlight that exposure to suboptimal temperatures induces structural and metabolic modifications in rainbow trout gills, potentially as an adaptive response to thermal stress. This study contributes to the understanding of fish acclimation to cold environments, with implications for aquaculture and ecological resilience in changing climates. Full article

Background: Melanoma, one of the most aggressive forms of skin cancer, has seen significant therapeutic advances with immune checkpoint inhibitors (ICIs). However, many patients fail to respond or develop resistance, creating the need for adjunct strategies. Objective: The objective of this study is to critically evaluate how specific dietary patterns and nutrient-derived metabolites modulate melanoma metabolism and immunotherapy outcomes, emphasizing translational implications. Methods: We performed an integrative review of preclinical and clinical studies investigating dietary interventions in melanoma models and ICI-treated patients. Mechanistic insights were extracted from studies on nutrient transport, immunometabolism, and microbiome–immune interactions, including data from ongoing nutritional clinical trials. Results: Diets rich in fermentable fibers, plant polyphenols, and unsaturated lipids, such as Mediterranean and ketogenic diets, seem to contribute to the reprogramming of tumor metabolism and enhance CD8+ T-cell activity. Fasting-mimicking and methionine-restricted diets modulate T-cell fitness and tumor vulnerability via nutrient stress sensors (e.g., UPR, mTOR). High fiber intake correlates with favorable gut microbiota and improved ICI efficacy, while excess protein, methionine, or refined carbohydrates impair immune surveillance via lactate accumulation and immunosuppressive myeloid recruitment. Several dietary molecules act as network-level modulators of host and microbial proteins, with parallels to known drug scaffolds. Conclusions: Integrating dietary interventions into melanoma immunotherapy can significantly influence metabolic reprogramming by targeting metabolic vulnerabilities and reshaping the tumor–immune–microbiome axis. When combined with AI-driven nutrient–protein interaction mapping, this approach offers a precision nutrition paradigm that supports both physicians and patients, emerging as a novel layer to enhance and consolidate existing therapeutic strategies. Full article

Lactate is a key oncometabolite that plays a critical role in modulating the behavior and function of both tumor cells and tumor-associated stromal cells within the tumor microenvironment (TME). Cancer-associated fibroblasts (CAFs), as essential stromal components, engage in dynamic crosstalk with tumor cells through lactate-mediated signaling pathways. Elevated lactate levels in the TME primarily originate from metabolic reprogramming in tumor cells and CAFs. Notably, tumor-derived lactate not only promotes basement membrane remodeling and epithelial–mesenchymal transition (EMT) in CAFs but also influences their functional phenotype. Conversely, CAF-secreted lactate significantly contributes to tumor progression. Therapeutic strategies targeting lactate transport and metabolism—particularly through the inhibition of monocarboxylate transporters (MCTs) and lactate dehydrogenase (LDH)—have emerged as promising approaches in cancer treatment. This review summarizes the multifaceted roles of lactate and lactylation, elucidates the molecular mechanisms underlying lactate-mediated tumor–CAF crosstalk, and explores potential therapeutic interventions targeting lactate metabolism and CAFs. Full article

Aquaporins (AQPs) are a family of transmembrane water channel proteins facilitating the transport of water and, in some cases, small solutes such as glycerol, lactate, and urea. In the central nervous system (CNS), several aquaporins play crucial roles in maintaining water homeostasis, modulating cerebrospinal fluid (CSF) circulation, regulating energy metabolism, and facilitating neuroprotection under pathological conditions. Among them, AQP2, AQP4, AQP9, and AQP11 have been implicated in traumatic and non-traumatic brain injuries. The most abundant aquaporin (AQP) in the brain, AQP4, is essential for fluid regulation, facilitating water transport across the blood–brain barrier and glymphatic clearance. AQP2 is primarily known for its function in the kidneys, but it is also expressed in brain regions related to vasopressin signaling and CSF dynamics. AQP9 acts as a channel for glycerol and lactate, thus playing a role in metabolic adaptation during brain injury. AQP11, an intracellular aquaporin, is involved in oxidative stress responses and cellular homeostasis, with emerging evidence suggesting its role in neuroprotection. Aquaporins play a dual role in brain injury; while they help maintain homeostasis, their dysregulation can exacerbate cerebral edema, metabolic dysfunction, and inflammation. In traumatic brain injury (TBI), aquaporins regulate the formation and resolution of cerebral edema. In non-traumatic brain injuries, including ischemic stroke, aneurysmal subarachnoid hemorrhage (aSAH), and intracerebral hemorrhage (ICH), aquaporins influence fluid balance, energy metabolism, and oxidative stress responses. Understanding the specific roles of AQP2, AQP4, AQP9, and AQP11 in these brain injuries may lead to new therapeutic strategies to mitigate secondary damage and improve neurological outcomes. This review explores the function of the above aquaporins in both traumatic and non-traumatic brain injuries, highlighting their potential and limitations as therapeutic targets for neuroprotection and recovery. Full article

Tumor cell heterogeneity, e.g., in stroma-rich pancreatic ductal adenocarcinoma (PDAC), includes a differential metabolism of lactate. While being secreted as waste product by most cancer cells characterized by the glycolytic Warburg metabolism, it is utilized by a subset of highly malignant cancer cells running the reverse Warburg metabolism. Key drivers of lactate transport are the carrier proteins SLC16A1 (import/export) and SLC16A3 (export). Expression and function of both carriers are controlled by the chaperone Basigin (BSG), which itself is functionally controlled by the transmembrane protease serine 11B (TMPRSS11B). In this study we explored the impact of TMPRSS11B on the phenotype of PDAC cells under reverse Warburg conditions. Amongst a panel of PDAC cell lines, Panc1 and BxPc3 cells were identified to express TMPRSS11B at a high level, whilst other cell lines such as T3M4 did not. ShRNA-mediated TMPRSS11B knock-down in Panc1 and BxPc3 cells enhanced lactate import through SLC16A1, as shown by GFP/iLACCO1 lactate uptake assay, whereas TMPRSS1B overexpression in T3M4 dampened SLC16A1-driven lactate uptake. Moreover, knock-down and overexpression of TMPRSS11B differentially impacted proliferation and chemoresistance under reverse Warburg conditions in Panc1 or BxPc3 and T3M4 cells, respectively, as well as their stemness properties indicated by altered colony formation rates and expression of the stem cell markers Nanog, Sox2, KLF4 and Oct4. These effects of TMPRSS11B depended on both SLC16A1 and BSG as shown by gene silencing. Immunohistochemical analysis revealed a reciprocal expression of TMPRSS11B and BSG together with SLC16A1 in some areas of tumor tissues from PDAC patients. Those regions exhibiting low or no TMPRSS11B expression but concomitant high expression of SLC16A1 and BSG revealed greater amounts of KLF4. In contrast, other tumor areas exhibiting high expression of TMPRSS11B together with BSG and SLC16A1 were largely negative for KLF4 expression. Thus, the differential expression of TMPRSS11B adds to metabolic heterogeneity in PDAC and its absence supports the reverse Warburg metabolism in PDAC cells by the enhancement of BSG-supported lactate uptake through SLC16A1 and subsequent phenotype alterations towards greater stemness. Full article

Breast milk provides significant health benefits to both infants and mothers, offering protection against infections and enhancing cognitive development. This paper examines the complex effects of substance use disorder (SUD) during pregnancy and lactation, focusing on the pharmacokinetics of drug transfer into breast milk. It highlights the mechanisms by which drugs enter milk, emphasizing the roles of passive diffusion and active transport, particularly through breast cancer resistance protein (BCRP). The study explores the impact of various substances on fetal and infant health, with a focus on the relative infant dose (RID) and milk-to-plasma (MP) ratio as key metrics for assessing drug safety in breastfeeding. The findings underscore the need for careful evaluation of maternal drug use during lactation to balance the benefits of breastfeeding with potential risks. Full article

Background/Objectives: A maternal high-fat diet (HFD) impairs brain structure in offspring. In turn, fish oil (FO) rich in n-3 polyunsaturated fatty acids (PUFAs) has neuroprotective effects. Therefore, we investigated whether maternal HFD exposure affected the neurological reflexes, neuron morphology, and n-3 PUFA levels in the cerebral cortex of the offspring and whether these effects were mitigated by maternal FO consumption. Methods: Female Sprague Dawley rats received a control diet (CD, 10% Kcal fat) or HFD (45% Kcal fat) five weeks before mating and throughout pregnancy and lactation. From mating, a subgroup of HFD was supplemented with 11.4% FO into the diet (HFD-FO). Neurological reflexes were evaluated from postnatal day (PND) 3 until PND20. Brains were removed at PND22 for neuron morphology analysis. Moreover, fatty acid composition and transcripts of genes encoding for factors associated with synapse transmission (SNAP-25), plasticity (BDNF), transport of DHA (MFSD2a), and inflammation (NF-κB and IL-1β) were quantified in prefrontal, motor, and auditory cortices. Results: FO diminished the effects of HFD on the number of thin and mushroom-shaped dendritic spines in the cerebral cortex in both sexes. It also reversed the HFD effects on the motor and auditory reflexes in female and male offspring, respectively. In males, FO up-regulated Bdnf transcript levels in the motor cortex compared with CD and HFD. In females, n-3 PUFAs were higher in HFD and HFD-FO than in CD in the auditory cortex. Conclusions: Our results highlight the protective role of maternal dietary n-3 PUFAs in counteracting the effects induced by HFD on the acquisition of neurological reflexes and neuronal morphology in the cerebral cortex of the offspring of both sexes. Full article

Glucose delivery to the brain requires transporters at the blood–brain barrier (BBB), whose downregulation may be associated with neuronal deficits in Alzheimer’s disease (AD). Whether this downregulation is due to reduced demand or primary BBB dysfunction remains unclear. We investigated novel 18F-Fluorodeoxyglucose Positron Emission Tomography (18F-FDG-PET) measures, namely ventricles (FDG_Ventricles) and cortical uptake (FDG_Cortex), and the FDG_Ventricles/FDG_Cortex ratio in 224 patients with AD compared to those in 35 controls (CTRLs). AD patients showed lower FDG_Cortex and FDG_Ventricles and higher cerebrospinal fluid (CSF) lactates than CTRLs. We found a positive correlation between FDG_Cortex and FDG_Ventricles in both groups, although this was less strong in AD patients (AD: r = 0.358; p < 0.001; CTRL: r = 0.516; p = 0.003). Multivariate regression analyses showed that only older age was associated with reduced FDG_Cortex and FDG_Ventricles in CTRLs. Conversely, lower FDG_Cortex was associated with higher Qalb and higher plasma glucose levels within the AD group. Moreover, lower FDG_Ventricles and FDG_Ventricles/FDG_Cortex ratios were associated with elevated CSF lactates in this group. Stratifying AD patients by Apolipoprotein E (APOE) genotype revealed distinct patterns. In APOE ε3 homozygotes, FDG_Cortex showed no associations, while FDG_Ventricles and FDG_Ventricles/FDG_Cortex were negatively associated with CSF lactate. In APOE ε4 carriers, lower FDG_Cortex was linked to higher plasma glucose and QAlb, whereas FDG_Ventricles and FDG_Ventricles/FDG_Cortex were positively associated with CSF p-tau/Aβ42. Our findings suggest that, in patients with AD, FDG_Ventricles and the FDG_Ventricles/FDG_Cortex ratio may reflect alterations in brain metabolism and glucose extraction capacity. These parameters are differently linked with age, BBB integrity, and metabolic dysfunction (CSF lactates), according to APOE genotype. Full article