Variation In Metabolism Research Articles

Ethanol concentrations in various biological specimens: Living and postmortem forensic toxicology analysis and comprehensive literature review

Alcohol use upsurges the risk for many chronic ill-health consequences such as hepatitis, malignancies, and disastrous outcomes like road traffic accidents ending in fatal injuries. Biochemical and toxicological analysis of different body fluids is crucial for identifying the cause of death and postmortem interval in many forensic cases. Blood, urine, and vitreous fluid are the most valuable body fluids for detecting alcohol during any toxicological analysis. Alcohol is responsible for widespread morbidity and mortality worldwide. Blood alcohol concentration (BAC) is a necessary toxicological test to investigate various crime and accident scenes. This study comprehensively explores the demographic characteristics, BAC distribution, and correlations of alcohol concentrations in postmortem and living cases. Postmortem cases (N = 166) reveal intriguing demographic patterns, with notable variations in year distribution, nationality, sex, age groups, occupation, smoking habits, place of death, and psychiatric history. Living cases (N = 483) exhibit distinct demographic profiles, emphasizing differences in year distribution, nationality, sex, age groups, and smoking habits.Analysis of BAC distribution reveals diverse patterns in both postmortem and living cases, providing valuable insights into the prevalence of different BAC levels in each group. Correlation analyses unveil strong associations between alcohol concentrations in various biological samples in postmortem cases, highlighting the interdependence of blood, vitreous, and urine alcohol concentrations. Conversely, living cases display a moderate positive correlation between blood and urine alcohol concentrations.Comparative analyses showcase significant differences in mean alcohol concentrations between postmortem and living cases, suggesting variations in alcohol metabolism and distribution. These findings underscore the importance of considering temporal factors in interpreting alcohol concentrations in forensic and clinical contexts.In conclusion, this study enhances our understanding of alcohol-related incidents by delineating demographic profiles, BAC distributions, and correlations between different biological samples. Such insights are crucial for refining investigative and clinical approaches, contributing to the broader fields of forensic science and public health.

Lipidomics revealed alterations in glycerophospholipid metabolism in skin squamous cell carcinoma.

Skin squamous cell carcinoma (SCC) is a prevalent malignancy, and dysregulated lipid metabolism has been implicated in its pathogenesis. However, detailed characterization of lipid alterations in SCC remains limited. We analyzed lipid metabolic variations in tissue samples from 34 SCC patients and adjacent healthy tissues (located more than 1 cm from the tumor margin) using liquid chromatography-mass spectrometry (LC-MS). Data visualization and discriminatory lipid profiles were identified using principal component analysis (PCA) and sparse partial least squares discriminant analysis (sPLS-DA). Key lipids involved in the SCC metabolism were identified and further validated using an external data set (from a previous study, which similarly explored lipid profiles in oral SCC using lipidomics approaches). Pathway enrichment analysis was conducted to elucidate the metabolic pathways associated with these key lipids. Eight lipids were identified by comparing SCC and healthy tissues including PI(16:0/22:4), PI(18:1/20:4), PE(16:0/20:4), PE(16:0/22:5), PE(16:0/22:6), PE(18:1/20:3), PC(18:1/20:2), and PC(18:2/20:2), as confirmed by independent datasets. All of these lipids were upregulated in SCC tumor tissues. Pathway enrichment analysis revealed significant alterations in glycerophospholipid metabolic pathways, particularly affecting the metabolism of diacylglycerophosphocholines, glycerophosphoethanolamines, and glycerophosphoinositols. Our findings reveal that dysregulated glycerophospholipid metabolism plays a pivotal role in the development of SCC.

Shining a Light on Inflammation as a Critical Modulator of Drug Metabolism.

Since his graduate studies on alcohol induction of a novel cytochrome P450 (P450) enzyme, through his postdoctoral work on hormonal regulation of sexually differentiated cytochrome P450s (P450s), the author has maintained an interest in the regulation of drug metabolizing enzymes. This article is a recounting of his scientific career and focuses on his laboratory's work on inflammatory regulation of P450 enzymes that formed the basis for the Bernard B. Brodie Award. Key findings and publications are identified and discussed that contributed to the elucidation of some important principles: 1) inflammatory stimuli generally downregulate P450 enzymes, resulting in reduced metabolism of substrate drugs; 2) the main mechanism for this downregulation is transcriptional and involves both the activation of negatively acting transcription factors and the suppression of positive transcription factors; 3) inflammatory cytokines such as interleukin 1, interleukin 6, and tumor necrosis factor α act on hepatocytes to mediate this regulation; 4) these cytokines selectively regulate different P450 enzymes, and therefore different P450s are downregulated in different inflammatory diseases or disease models; 5) nitric oxide formed by inducible nitric oxide synthase 2 reacts with P450s in an enzyme-specific manner to stimulate their proteolytic degradation; and 6) both tyrosine nitration and heme nitrosylation are likely required for this NO-stimulated degradation. Finally, findings from clinical studies are discussed that shine a light on the importance of P450 regulation by inflammation for drug development, clinical practice, and personalized medicine. SIGNIFICANCE STATEMENT: This article discusses the key publications and findings in the author's laboratory that helped to identify inflammation as an important factor contributing to interindividual variation in drug metabolism.

Blueberries in focus: Exploring the phytochemical potentials and therapeutic applications

Blueberries, which belong to the Vaccinium spp. Genus, have attracted considerable interest because of their abundant phytochemical composition and potential for medicinal uses. The present study examines the many phytochemicals found in blueberries, such as anthocyanins, flavonoids, phenolic acids, and stilbenes, as well as their biological activities contributing to the health benefits of blueberries. Anthocyanins, the primary pigments that give blueberries their unique color, are renowned for their powerful antioxidant capabilities. These substances counteract oxidative stress by neutralizing free radicals, decreasing the likelihood of developing chronic illnesses such as cardiovascular disease, cancer, and neurological disorders. Furthermore, the presence of flavonoids and phenolic acids in blueberries contributes to their ability to reduce inflammation, prevent cancer, and protect the brain, improving their potential for therapeutic use. This study delves into the bioavailability and metabolism of these phytochemicals, specifically examining the impact of factors like food composition, gut microorganisms, and individual metabolic variations on their effectiveness. Both clinical and preclinical studies provide strong evidence for the beneficial effects of blueberries on multiple health factors, such as enhanced cognitive function, lowered blood pressure, and improved insulin sensitivity. These findings suggest that blueberries may play a significant role in managing conditions like Alzheimer's disease, hypertension, and diabetes. Moreover, this study examines the synergistic impacts of blueberry phytochemicals, suggesting that the health advantages of blueberries arise not alone from individual substances but also from their collective interactions. Proposed future study areas include the advancement of functional foods and nutraceuticals derived from blueberries, as well as the need for standardized clinical studies to determine appropriate dose guidelines and ensure long-term safety. Overall, the significant variety of phytochemicals in blueberries and their potential for therapeutic use make them a promising functional food. Further research into these substances' mechanisms of action and therapeutic uses will clarify their function in enhancing human health and avoiding illness.

A comparative metabolomic analysis reveals the metabolic variations among cartilage of Kashin-Beck disease and osteoarthritis.

The metabolic variations between the cartilage of osteoarthritis (OA) and Kashin-Beck disease (KBD) remain largely unknown. Our study aimed to address this by conducting a comparative analysis of the metabolic profiles present in the cartilage of KBD and OA. Cartilage samples from patients with KBD (n = 10) and patients with OA (n = 10) were collected during total knee arthroplasty surgery. An untargeted metabolomics approach using liquid chromatography coupled with mass spectrometry (LC-MS) was conducted to investigate the metabolomics profiles of KBD and OA. LC-MS raw data files were converted into mzXML format and then processed by the XCMS, CAMERA, and metaX toolbox implemented with R software. The online Kyoto Encyclopedia of Genes and Genomes (KEGG) database was used to annotate the metabolites by matching the exact molecular mass data of samples with those from the database. A total of 807 ion features were identified for KBD and OA, including 577 positive (240 for upregulated and 337 for downregulated) and 230 negative (107 for upregulated and 123 for downregulated) ions. After annotation, LC-MS identified significant expressions of ten upregulated and eight downregulated second-level metabolites, and 183 upregulated and 162 downregulated first-level metabolites between KBD and OA. We identified differentially expressed second-level metabolites that are highly associated with cartilage damage, including dimethyl sulfoxide, uric acid, and betaine. These metabolites exist in sulphur metabolism, purine metabolism, and glycine, serine, and threonine metabolism. This comprehensive comparative analysis of metabolism in OA and KBD cartilage provides new evidence of differences in the pathogenetic mechanisms underlying cartilage damage in these two conditions.

Oomycete Metabolism Is Highly Dynamic and Reflects Lifestyle Adaptations.

The selective pressure of pathogen-host symbiosis drives adaptations. How these interactions shape the metabolism of pathogens is largely unknown. Here, we use comparative genomics to systematically analyze the metabolic networks of oomycetes, a diverse group of eukaryotes that includes saprotrophs as well as animal and plant pathogens, with the latter causing devastating diseases with significant economic and/or ecological impacts. In our analyses of 44 oomycete species, we uncover considerable variation in metabolism that can be linked to lifestyle differences. Comparisons of metabolic gene content reveal that plant pathogenic oomycetes have a bipartite metabolism consisting of a conserved core and an accessory set. The accessory set can be associated with the degradation of defense compounds produced by plants when challenged by pathogens. Obligate biotrophic oomycetes have smaller metabolic networks, and taxonomically distantly related biotrophic lineages display convergent evolution by repeated gene losses in both the conserved as well as the accessory set of metabolisms. When investigating to what extent the metabolic networks in obligate biotrophs differ from those in hemibiotrophic plant pathogens, we observe that the losses of metabolic enzymes in obligate biotrophs are not random and that gene losses predominantly influence the terminal branches of the metabolic networks. Our analyses represent the first metabolism-focused comparison of oomycetes at this scale and will contribute to a better understanding of the evolution of oomycete metabolism in relation to lifestyle adaptation. Numerous oomycete species are devastating plant pathogens that cause major damage in crops and natural ecosystems. Their interactions with hosts are shaped by strong selection, but how selection affects adaptation of the primary metabolism to a pathogenic lifestyle is not yet well established. By pan-genome and metabolic network analyses of distantly related oomycete pathogens and their nonpathogenic relatives, we reveal considerable lifestyle- and lineage-specific adaptations. This study contributes to a better understanding of metabolic adaptations in pathogenic oomycetes in relation to lifestyle, host, and environment, and the findings will help in pinpointing potential targets for disease control. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Using machine learning to identify environmental factors that collectively determine microbial community structure of activated sludge

Activated sludge (AS) microbial communities are influenced by various environmental variables. However, a comprehensive analysis of how these variables jointly and nonlinearly shape the AS microbial community remains challenging. In this study, we employed advanced machine learning techniques to elucidate the collective effects of environmental variables on the structure and function of AS microbial communities. Applying Dirichlet multinomial mixtures analysis to 311 global AS samples, we identified four distinct microbial community types (AS-types), each characterized by unique microbial compositions and metabolic profiles. We used 14 classical linear and nonlinear machine learning methods to select a baseline model. The extremely randomized trees demonstrated optimal performance in learning the relationship between environmental factors and AS types (with an accuracy of 71.43%). Feature selection identified critical environmental factors and their importance rankings, including latitude (Lat), longitude (Long), precipitation during sampling (Precip), solids retention time (SRT), effluent total nitrogen (Effluent TN), average temperature during sampling month (Avg Temp), mixed liquor temperature (Mixed Temp), influent biochemical oxygen demand (Influent BOD), and annual precipitation (Annual Precip). Significantly, Lat, Long, Precip, Avg Temp, and Annual Precip, influenced metabolic variations among AS types. These findings emphasize the pivotal role of environmental variables in shaping microbial community structures and enhancing metabolic pathways within activated sludge. Our study encourages the application of machine learning techniques to design artificial activated sludge microbial communities for specific environmental purposes.

Antiplatelet Therapy and Platelet Activity Testing for Neurointerventional Procedures

The management of antiplatelet medications in neurointerventional procedures remains a subject of considerable variability and debate. This review article explores the diverse clinical practices and the impact of different antiplatelet regimens and platelet activity testing on patient outcomes in neurointerventional treatments. While much of the evidence around antiplatelet therapies largely stems from randomized trials in cardiac and peripheral vascular diseases, their application in neurointerventional settings requires nuanced consideration. Various assays exist to assess individual platelet function, yet the optimal assay, thresholds, and agents remain uncertain due to interpatient variability in medication responsiveness. Expert consensus groups have attempted to standardize antiplatelet management, which is summarized for elective and emergent neurointerventional procedures. Clopidogrel, a commonly used antiplatelet, faces challenges such as genetic variability in metabolism and drug–drug interactions, impacting its effectiveness. Other agents, such as ticagrelor and prasugrel, offer alternatives with different mechanisms of action and potential advantages. Additionally, short‐acting intravenous P2Y 12 inhibitors, such as cangrelor, and glycoprotein IIb/IIIa inhibitors provide options for acute bridging therapy in neurointerventional cases. Despite advancements, significant gaps persist in understanding the optimal antiplatelet management for neurovascular procedures. While platelet function testing is commonly used, its clinical utility and standardization remain an area of investigation. This review underscores the need for further multicenter studies to delineate best practices and optimize patient outcomes in neurointerventional settings.

A 3D Pancreatic Cancer Model with Integrated Optical Sensors for Noninvasive Metabolism Monitoring and Drug Screening.

A distinct feature of pancreatic ductal adenocarcinoma (PDAC) is a prominent tumor microenvironment (TME) with remarkable cellular and spatial heterogeneity that meaningfully impacts disease biology and treatment resistance. The dynamic crosstalk between cancer cells and the dense stromal compartment leads to spatially and temporally heterogeneous metabolic alterations, such as acidic pH that contributes to drug resistance in PDAC. Thus, monitoring the extracellular pH metabolic fluctuations within the TME is crucial to predict and to quantify anticancer drug efficacy. Here,a simple and reliable alginate-based 3D PDAC model embedding ratiometric optical pH sensors and cocultures of tumor (AsPC-1) and stromal cells for simultaneously monitoring metabolic pH variations and quantify drug response is presented. By means of time-lapse confocal laser scanning microscopy (CLSM) coupled with a fully automated computational analysis, the extracellular pH metabolic variations are monitored and quantified over time during drug testing with gemcitabine, folfirinox, and paclitaxel, commonly used in PDAC therapy. In particular, the extracellular acidification is more pronounced after drugs treatment, resulting in increased antitumor effect correlated with apoptotic cell death. These findings highlight the importance of studying the influence of cellular metabolic mechanisms on tumor response to therapy in 3D tumor models, this being crucial for the development of personalized medicine approaches.

Metabolomic Disparities in Intraocular Fluid Across Varied Stages of Cataract Progression: Implications for the Analysis of Cataract Development.

Introduction: The lens's metabolic demands are met through a continuous circulation of aqueous humor, encompassing a spectrum of components such as organic and inorganic ions, carbohydrates, glutathione, urea, amino acids, proteins, oxygen, carbon dioxide, and water. Metabolomics is a pivotal tool, offering an initial insight into the complexities of integrated metabolism. In this investigative study, we systematically scrutinize the composition of intraocular fluid in individuals afflicted with cataracts. Methods: The investigation involved a comprehensive analysis of aqueous humor samples from a cohort comprising 192 patients. These individuals were stratified by utilizing the SPONCS classification system, delineating distinct groups characterized by the hardness of cataracts. The analytical approach employed targeted quantitative metabolite analysis using HILIC-based liquid chromatography coupled with high-resolution mass spectrometric detection. The metabolomics data analysis was performed with MetaboAnalyst 5.0. Results: The results of the enrichment analysis have facilitated the inference that the discerned disparities among groups arise from disruptions in taurine and hypotaurine metabolism, variations in tryptophan metabolism, and modifications in mitochondrial beta-oxidation of short-chain saturated fatty acids and pyrimidine metabolism. Conclusion: A decline in taurine concentration precipitates diminished glutathione activity, prompting an elevated requirement for NAD+ and instigating tryptophan metabolism along the kynurenine pathway. Activation of this pathway is additionally prompted by interferon-gamma and UV radiation, leading to the induction of IDO. Concurrently, heightened mitochondrial beta-oxidation signifies a distinctive scenario in translocating fatty acids into the mitochondria, enhancing energy production.

Exploring the Regulation of Cytochrome P450 in SH-SY5Y Cells: Implications for the Onset of Neurodegenerative Diseases.

Human individual differences in brain cytochrome P450 (CYP) metabolism, including induction, inhibition, and genetic variation, may influence brain sensitivity to neurotoxins and thus participate in the onset of neurodegenerative diseases. The aim of this study was to explore the modulation of CYPs in neuronal cells. The experimental approach was focused on differentiating human neuroblastoma SH-SY5Y cells into a phenotype resembling mature dopamine neurons and investigating the effects of specific CYP isoform induction. The results demonstrated that the differentiation protocols using retinoic acid followed by phorbol esters or brain-derived neurotrophic factor successfully generated SH-SY5Y cells with morphological neuronal characteristics and increased neuronal markers (NeuN, synaptophysin, β-tubulin III, and MAO-B). qRT-PCR and Western blot analysis showed that expression of the CYP 1A1, 3A4, 2D6, and 2E1 isoforms was detectable in undifferentiated cells, with subsequent increases in CYP 2E1, 2D6, and 1A1 following differentiation. Further increases in the 1A1, 2D6, and 2E1 isoforms following β-naphthoflavone treatment and 1A1 and 2D6 isoforms following ethanol treatment were evident. These results demonstrate that CYP isoforms can be modulated in SH-SY5Y cells and suggest their potential as an experimental model to investigate the role of CYPs in neuronal processes involved in the development of neurodegenerative diseases.

Copeptin's role in traumatic brain injury: The promising quest for a new biomarker

ObjectiveTraumatic brain injury (TBI) necessitates reliable biomarkers to improve patient care. This study explored copeptin as a potential biomarker in TBI and its relation to vasopressin (ADH) in such patients. MethodsA cross-sectional study was conducted on 50 TBI patients. Exclusion criteria included specific medical conditions and recent traumatic events. Copeptin and ADH testing were performed within 30 days post-trauma. Patient data, Glasgow Coma Scale (GCS) scores, imaging results, and the need for surgical intervention were obtained from medical charts. ResultsCopeptin levels negatively correlated with GCS scores (ρ = − 0.313, p = 0.027), indicating a potential association with trauma severity. Copeptin levels (mean: 3.22 pmol/L, median 2.027 pmol/L, SD = 3.15) tended to be lower than those found in the normal population, suggesting possible neuroendocrine dysfunction post-TBI. ADH levels (mean: 67.93 pmol/L, median 56.474 pmol/L SD = 47.67) were higher than the normal range and associated with the need for surgery (p = 0.048). Surprisingly, copeptin and ADH levels negatively correlated (r = − 0.491; p < 0.001), potentially due to differences in degradation processes and physiological variations in TBI patients. ConclusionCopeptin shows potential as a predictive biomarker for assessing TBI severity and predicting patient outcome. However, its complex relationship with ADH in TBI requires further investigation. Careful interpretation is needed due to potential variations in excretion dynamics and metabolism. Larger studies on TBI patient cohorts are essential to validate copeptin as a reliable biomarker and improve patient care in TBI.

Uncovering phytochemicals quantitative evolution in avocado fruit mesocarp during ripening: A targeted LC-MS metabolic exploration of Hass, Fuerte and Bacon varieties

Avocado ripening entails intricate physicochemical transformations resulting in desirable characteristics for consumption; however, its impact on specific metabolites and its cultivar dependence remains largely unexplored. This study employed LC-MS to quantitatively monitor 30 avocado pulp metabolites, including phenolic compounds, amino acids, nucleosides, vitamins, phytohormones, and related compounds, from unripe to overripe stages, in three commercial varieties (Hass, Fuerte, and Bacon). Multivariate statistical analysis revealed significant metabolic variations between cultivars, leading to the identification of potential varietal markers. Most monitored metabolites exhibited dynamic quantitative changes. Although phenolic compounds generally increased during ripening, exceptions such as epicatechin and chlorogenic acid were noted. Amino acids and derivatives displayed a highly cultivar-dependent evolution, with Fuerte demonstrating the highest concentrations and most pronounced fluctuations. In contrast to penstemide, uridine and abscisic acid levels consistently increased during ripening. Several compounds characteristic of the Bacon variety were delineated but require further research for identification and role elucidation.

P-159 Single-cell high-throughput methylation and transcriptomic analysis indicates variations in sensitivity to Folate-mediated one-carbon metabolism in mouse preimplantation embryos

Abstract Study question Do Folate-mediated one-carbon metabolism (FOCM) supplements impose methylating conditions that influence methylation and transcriptomic profiles during preimplantation period of mouse embryos? Summary answer Subtle differences in embryo methylation profiles were induced by FOCM supplements, despite transcriptomic signatures remained stable and selective genes related to metabolism were activated. What is known already Previous human studies of populations affected by seasonal variations in diet including folate availability have shown methylation changes in specific loci known as metastable epialleles (MEs). MEs exhibit stability across tissues, indicating these could be potential biosensors for heightened sensitivity to external methylating influences in early embryonic stages. Despite significant progress in IVF embryo culture conditions, the sensitivity to the outer metabolic environment during the extensive genomic transformation of embryo reprogramming remains inadequately understood. Study design, size, duration This is a prospective experimental study conducted from January 2023 to December 2023. A total of 111 fresh mouse zygotes (F1 hybrid (B6/CBA)) were subjected embryo culture conditions with different FOCM supplies of 5-MTHF and betaine up to expanded blastocyst stage (105 hours). At different timepoints, individual embryos were collected and disaggregated in individual cells for downstream single-cell analysis. Participants/materials, setting, methods Mouse zygotes were collected from the oviduct, washed and culture in KSOM supplemented with 5-MTHF and betaine at respectively concentrations of 50μM and 50μg/mL (THF/bet(50)), 10μM and 10μg/mL (THF/bet(10)) and no supplement till blastocyst stage at 37 °C, 6%CO2 and 5%O2. Individual embryos were collected at 2 cells, 4 cells, 8 cells, Morula and Blastocyst stage and disaggregated into single cells for subsequent single-cell RNAseq (SmartSeq2) and single-cell methylome analysis through Splinted Ligation Adapter Tagging (scSPLAT). Main results and the role of chance The methylation analysis conducted though scSPLAT revealed a comprehensive reduction in global methylation levels throughout developmental stages. Notably, zygotes exhibited a maximal proportion of methylated cytosines at CpG sites, while blastocysts displayed minimal methylation levels, with sporadic increases in isolated cells. Quantitative profiling indicated lower methylation intensities in treated embryos from zygote to 4 cells, followed by a reversal trend from 8 cells to blastocyst, suggestive of an enhanced assimilation of one-carbon metabolism (FOCM) supplements. Transcriptomic profiles obtained through scRNAseq exhibited correlation with developmental trajectories from zygote to blastocyst. However, no discernible variations were attributed to the combined exposure of Betaine and 5-MTHF. Gene enrichment analysis of differentially expressed genes at various timepoints highlighted specific metabolic responses, including mitochondrial oxidative stress and variations in glutathione metabolism. This suggests that the folate forms utilized in this study may possess a protective role as antioxidants, contributing to the observed effects on gene expression during embryonic development. Limitations, reasons for caution The methylation analysis shown in this study was a pilot carried out with low coverage of sequencing deepness, further analysis are ongoing to increase reads coverage. Wider implications of the findings Exposure of mouse embryos to FOCM enhanced global methylation during cell division from 8 cells to blastocyst, indicating heightened assimilation during DNA synthesis. While the transcriptomic signature remained stable, increased expression of genes linked to mitochondrial oxidative stress and glutathione metabolism suggests FOCM’s potential antioxidant role. Trial registration number not applicable

Effects of protein and forage source on performance, and splanchnic and mammary net fluxes of nutrients in lactating dairy cows

This study was conducted to determine if the decreased MP supply predicted by the NRC (2001) when canola meal (CM) substitutes soybean meal (SBM) was supported by direct measurement of net portal absorption of AA or energy-yielding nutrients, plus the impact of the type of forage in CM-based rations. Nine Holstein cows with indwelling catheters in splanchnic blood vessels, 8 also with a ruminal cannula were used to examine the effects of protein source in corn silage-based diets, comparing SBM versus CM, and forage source in CM-based diets, comparing corn versus grass silage. The cows were allocated to a triple 3 × 3 Latin square design with 21-d periods. The 3 experimental diets, formulated to be isoenergetic and isonitrogenous, were based on: 1) SBM and corn silage (SoyCorn); 2) CM and corn silage (CanCorn) and 3) CM and cool-season grass silage (CanGrass). Averages of intake, milk yield and milk composition of the last 3 d of each period were used for statistical analyses. On d 21 of each period, 6 sets of arterial, portal, hepatic and mammary blood samples and 2 ruminal fluid samples were collected. On d 12 of period 2, the protein sources were incubated in nylon bags to determine 16h-ruminal disappearance of DM and N and to obtain 16-h residues. Finally, 5 d after the completion of the Latin square design, the mobile bag technique was used to determine DM and N intestinal disappearance of the 16-h residues of SBM and CM. Pre-planned contrasts were used to compare the effect of the protein source in cows fed corn silage, i.e., SoyCorn versus CanCorn, and the effect of forage in cows fed CM, i.e., CanCorn versus CanGrass. Data of the cow without a rumen canula could not be used because of health problem. In corn silage-based diets, substitution of SBM by CM tended to increase milk (6%) and milk fat (7%) yields. The 8% higher ruminal N disappearance and the 19% decreased MP supply from RUP predicted by NRC (2001) were not supported by the 25% decrease in ruminal ammonia concentration, similar net portal absorption of AA (except 22% higher for Met), and the 14% decrease in urea hepatic removal when CM substituted SBM. Ruminal incubation of CM in nylon bags does not appear suitable for adequate determination of the rumen by-pass of a protein source like CM. Inclusion of grass silage rather than corn silage in CM-based diets tended to increase milk (6%) and increased milk lactose (8%) yields. Neither protein nor forage source resulted in variations of metabolism of energy-yielding nutrients that could explain observed increments in cow performance. The present study indicates no decreased AA availability when CM substitutes SBM. Therefore, substitution of SBM by CM in diets based on corn silage and CM in corn- or grass silage-diets can be used successfully in high producing dairy cows.

Genetic variation present in the CYP3A4 gene in Ni-Vanuatu and Kenyan populations in malaria endemicity

Cytochrome P450 3A4 (CYP3A4) enzyme is involved in the metabolism of about 30 % of clinically used drugs, including the antimalarials artemether and lumefantrine. CYP3A4 polymorphisms yield enzymatic variants that contribute to inter-individual variation in drug metabolism. Here, we examined CYP3A4 polymorphisms in populations from malaria-endemic islands in Lake Victoria, Kenya, and Vanuatu, to expand on the limited data sets. We used archived dried blood spots collected from 142 Kenyan and 263 ni-Vanuatu adults during cross-sectional malaria surveys in 2013 and 2005–13, respectively, to detect CYP3A4 variation by polymerase chain reaction (PCR) and sequencing. In Kenya, we identified 14 CYP3A4 single nucleotide polymorphisms (SNPs), including the 4713G (CYP3A4∗1B; allele frequency 83.9 %) and 19382A (CYP3A4∗15; 0.7 %) variants that were previously linked to altered metabolism of antimalarials. In Vanuatu, we detected 15 SNPs, including the 4713A (CYP3A4∗1A; 88.6 %) and 25183C (CYP3A4∗18; 0.6 %) variants. Additionally, we detected a rare and novel SNP C4614T (0.8 %) in the 5′ untranslated region. A higher proportion of CYP3A4 genetic variance was found among ni-Vanuatu populations (16 %) than among Lake Victoria Kenyan populations (8 %). Our work augments the scarce data sets and contributes to improved precision medicine approaches, particularly to anti-malarial chemotherapy, in East African and Pacific Islander populations.

Phenotype-Genotype Correlation Applying a Cocktail Approach and an Exome Chip Analysis Reveals Further Variants Contributing to Variation of Drug Metabolism.

Although great progress has been made in the fine-tuning of diplotypes, there is still a need to further improve the predictability of individual phenotypes of pharmacogenetically relevant enzymes. The aim of this study was to analyze the additional contribution of sex and variants identified by exome chip analysis to the metabolic ratio of five probe drugs. A cocktail study applying dextromethorphan, losartan, omeprazole, midazolam, and caffeine was conducted on 200 healthy volunteers. CYP2D6, 2C9, 2C19, 3A4/5, and 1A2 genotypes were analyzed and correlated with metabolic ratios. In addition, an exome chip analysis was performed. These SNPs correlating with metabolic ratios were confirmed by individual genotyping. The contribution of various factors to metabolic ratios was assessed by multiple regression analysis. Genotypically predicted phenotypes defined by CPIC discriminated very well the log metabolic ratios with the exception of caffeine. There were minor sex differences in the activity of CYP2C9, 2C19, 1A2, and CYP3A4/5. For dextromethorphan (CYP2D6), IP6K2 (rs61740999) and TCF20 (rs5758651) affected metabolic ratios, but only IP6K2 remained significant after multiple regression analysis. For losartan (CYP2C9), FBXW12 (rs17080138), ZNF703 (rs79707182), and SLC17A4 (rs11754288) together with CYP diplotypes, and sex explained 50% of interindividual variability. For omeprazole (CYP2C19), no significant influence of CYP2C:TG haplotypes was observed, but CYP2C19 rs12777823 improved the predictability. The comprehensive genetic analysis and inclusion of sex in a multiple regression model significantly improved the explanation of variability of metabolic ratios, resulting in further improvement of algorithms for the prediction of individual phenotypes of drug-metabolizing enzymes.

Variation in nonstructural carbohydrates and antioxidant metabolism in wheat leaf and spike under changing CO2 and nitrogen supply

Variation in nonstructural carbohydrates and antioxidant metabolism in wheat leaf and spike under changing CO2 and nitrogen supply

Metabolic Response Variability Following High-Fat and High-Carbohydrate Meals: A Study Protocol

Metabolic Response Variability Following High-Fat and High-Carbohydrate Meals: A Study Protocol

Centimetre scale functional dispersal limitation of freshwater copiotrophs.

The freshwater microbiome harbours numerous copiotrophic bacteria that rapidly respond to elevated substrate concentrations. We hypothesized that their high centimetre-scale beta diversity in lake water translates into pronounced metabolic variability, and that a large fraction of microbial 'metabolic potential' originates from point sources such as fragile organic aggregates. Three experiments were conducted in pre-alpine Lake Zurich over the course of a harmful cyanobacterial bloom: Spatially explicit 9 ml 'syringe' samples were collected in situ at centimetre distances along with equally sized 'mixed' samples drawn from pre-homogenized lake water and incubated in BIOLOG EcoPlate substrate arrays. Fewer compounds promoted bacterial growth in the syringe than in the mixed samples, in particular during the pre- and late bloom periods. Community analysis of enrichments on three frequently utilized substrates revealed both pronounced heterogeneity and functional redundancy. Bacterial consortia had higher richness in mixed than in syringe samples and differed in composition. Members of the Enterobacter cloacae complex dominated the EcoPlate assemblages during the mid-bloom period irrespective of treatment or substrate. We conclude that small-scale functional dispersal limitation among free-living copiotrophs in lake water reduces local biotransformation potential, and that lacustrine blooms of harmful cyanobacteria can be environmental reservoirs for metabolically versatile potential pathogens.