Affect Nutrient Metabolism Research Articles

Dietary protein affects tissue accumulation of mercury and induces hepatic Phase I and Phase II enzyme expression after co-exposure with methylmercury in mice

Methylmercury (MeHg) is a ubiquitous environmental contaminant, well known for its neurotoxic effects. MeHg can interact with several nutrients in the diet and affect nutrient metabolism, however the interaction between MeHg and dietary proteins has not been thoroughly investigated. Male BALB/c mice were fed diets based on either casein, cod or chicken as protein sources, which were or were not spiked with MeHg (3.5 mg Hg kg−1). Following 13 weeks of dietary exposure to MeHg, the animals accumulated mercury in a varying degree depending on the diet, where the levels of mercury were highest in the mice fed casein and MeHg, lower in mice fed cod and MeHg, and lowest in mice fed chicken and MeHg in all tissues assessed. Assessment of gut microbiota revealed differences in microbiota composition based on the different protein sources. However, the introduction of MeHg eliminated this difference. Proteomic profiling of liver tissue uncovered the influence of the dietary protein sources on a range of enzymes related to Phase I and Phase II detoxification mechanisms, suggesting an impact of the diet on MeHg metabolism and excretion. Also, enzymes linked to pathways including methionine and glycine betaine cycling, which in turn impact the production of glutathione, an important MeHg conjugation molecule, were up-regulated in mice fed chicken as dietary protein. Our findings indicate that dietary proteins can affect expression of hepatic enzymes that potentially influence MeHg metabolism and excretion, highlighting the relevance of considering the dietary composition in risk assessment of MeHg through dietary exposure.

Significance of the Gut-Brain Axis in the Development of Overweight and Obesity

Introduction: The global obesity crisis results from inactive lifestyles and poor diets, increasing the risk of metabolic disorders. Emerging research links obesity with gut microbiome changes influenced by factors like age, genetics, and diet. Gut-brain communication via neural, endocrine, and inflammatory pathways, influenced by microbial compounds, affects nervous system function. Materials and Methods of Research: A thorough literature review was performed using PubMed and Google Scholar, employing keywords related to the gut-brain axis and obesity. Results: Obesity shifts gut microbiota composition due to factors like childbirth method, diet, antibiotics, and environment. This imbalance impacts metabolism, appetite, and insulin sensitivity. Gut microbes influence the brain, regulating energy balance and inflammation. Dysregulated tryptophan metabolism leads to insulin resistance. Gut-brain communication via the vagal nerve affects nutrient metabolism. Hormones like insulin and leptin, along with microbial metabolites, affect lipid metabolism and appetite. Gut microbiota abundance correlates with leptin signaling, and changes in ghrelin levels relate to microbiota composition. Microbial presence affects food cravings. Inflammation in obesity is linked to gut microbiota changes, mediated by bile acids and microbial metabolites. Interventions like probiotics and fecal microbiota transplantation offer potential for managing obesity. Emerging therapies like peptide D3 hold promise but require further study. Conclusion: The microbiome-gut-brain axis is vital in obesity, affecting metabolism, inflammation, and appetite. Utilizing interventions such as dietary adjustments and probiotics targeting gut-brain signaling shows promise in managing obesity. Personalized approaches are crucial due to microbiome complexity. Further research is needed to develop effective therapies for the obesity epidemic.

Fetal Myocardial Expression of GLUT1: Roles of BPA Exposure and Cord Blood Exosomes in a Rat Model.

Dietary exposure to Bisphenol A (BPA), an industrial chemical present in food containers, affects nutrient metabolism in the myocardium of offspring during intrauterine life. Using a murine model, we observed that fetal hearts from mothers exposed to BPA (2.5 μg/kg/day) for 20 days before mating and for all of the gestation had decreased expression of glucose transporter-1 (GLUT1), the principal sugar transporter in the fetal heart, and increased expression of fatty acid cluster of differentiation 36 transporter (CD36), compared to control fetuses from vehicle-treated mothers. We confirmed the suppression of GLUT1 by exposing fetal heart organotypic cultures to BPA (1 nM) for 48 h but did not detect changes in CD36 compared to controls. During pregnancy, the placenta continuously releases extracellular vesicles such as exosomes into fetal circulation. These vesicles influence the growth and development of fetal organs. When fetal heart cultures were treated with cord blood-derived exosomes isolated from BPA-fed animals, GLUT1 expression was increased by approximately 40%. Based on our results, we speculate that exosomes from cord blood, in particular placenta-derived nanovesicles, could contribute to the stabilization of the fetal heart metabolism by ameliorating the harmful effects of BPA on GLUT1 expression.

Growth performance and efficiency of protein utilization in giant tiger prawn, Penaeus monodon reared in tarpaulin pond with and without faecal chamber

The accumulation of organic matter at the bottom of the pond greatly affects nutrient metabolism, feed efficiency, growth and productivity in giant tiger prawn cultivation. One of the causes is improper pool bottom construction The purpose of this study was to compare the growth performance and efficiency of protein utilization in giant tiger prawns consuming artificial feed supplemented with multi-enzymes and reared in tarpaulin ponds constructed between not and using the faecal chamber (FAMBER) or the space of metabolic waste and unconsumptioned feed (SOMECOF) at the bottom of the pond with a recirculating aquaculture system (RAS). A tarpaulin pond with a diameter of 3 m and a height of 100 cm filled with 80 cm of seawater. The tarpaulin pond is equipped with a transparent plastic roof, seawater and aeration installation, and a filter in the water pump tank. The average body weight of the experimental prawn used were 8-9 g. The feed given is pellet type artificial feed supplemented with multi-enzymes at a dose of 30 cc/kg of feed. The frequency of feeding were four times a day, namely at 07:00; 12:00; 17:00 and 22:00 with a dose of 5%. The parameters measured were growth performance including growth, condition factors and feed efficiency, while the efficiency of protein utilization included protein content, protein efficiency ratio, amino acid profile, index and score of essential amino acids of feed and experimental prawn. Data analysis was done descriptively. The results showed that all parameters of growth performance and efficiency of protein utilization in tiger prawns reared in tarpaulin ponds using FAMBER were better than those without FAMBER. Based on the results of the study, it was concluded that keeping giant tiger prawns in a tarpaulin pond using a FAMBER is better than not using a FAMBER.

Nutrition, genetic variation and male fertility.

Infertility affects nearly 50 million couples worldwide, with 40−50% of cases having a male factor component. It is well established that nutritional status impacts reproductive development, health and function, although the exact mechanisms have not been fully elucidated. Genetic variation that affects nutrient metabolism may impact fertility through nutrigenetic mechanisms. This review summarizes current knowledge on the role of several dietary components (vitamins A, B12, C, D, E, folate, betaine, choline, calcium, iron, caffeine, fiber, sugar, dietary fat, and gluten) in male reproductive health. Evidence of gene-nutrient interactions and their potential effect on fertility is also examined. Understanding the relationship between genetic variation, nutrition and male fertility is key to developing personalized, DNA-based dietary recommendations to enhance the fertility of men who have difficulty conceiving.

Bioinformatics analysis of differentially expressed proteins in alcoholic fatty liver disease treated with recombinant human cytoglobin.

Cytoglobin (Cygb) is a globin molecule that is ubiquitously expressed in all tissues and has a protective role under oxidative stress. It has also been demonstrated to be effective in the treatment of alcoholic fatty liver disease (AFLD). In order to study the molecular mechanisms underlying its beneficial effects for the treatment of alcoholic liver, two-dimensional electrophoresis and mass spectrometric analysis were performed on serum and liver tissues from an in vivo rat model of AFLD. A total of 26 differentially expressed proteins were identified in the serum and 20 differentially expressed proteins were identified in liver specimens. Using online bioinformatics tools, it was indicated that these differentially expressed proteins were primarily associated with pathways including binding and uptake of ligands by scavenger receptors, response to corticosteroid, plasma lipoprotein remodeling, regulation of complement cascade, hydrogen peroxide catabolic process, as well as response to nutrient and monosaccharide. The present results suggested that recombinant human Cygb exerts its role in the treatment of AFLD primarily through affecting nutrient metabolism, monocarboxylic acid biosynthesis, regulation of glutathione expression, plasma lipoprotein remodeling and removal of metabolic waste from the blood.

Increasing selenium supply during the close-up dry period improves nutrient metabolism and attenuates inflammatory response after calving in dairy cows.

The objective of this study was to investigate whether feeding selenium (Se)-replete cows a Se-yeast supplement in late pregnancy affects nutrient metabolism and inflammatory response during the periparturient period. Twenty cows were randomly assigned to two groups with 10 cows each. Cows in one group received Se-yeast at 0.3mg Se/kg DM during the last 4weeks before calving in addition to fed a TMR containing supplemented sodium selenite at 0.3mg Se/kg DM (Se-yeast), while cows in another group were only fed a TMR containing supplemented sodium selenite at 0.3mg Se/kg DM (Control). Blood samples were collected and analyzed for nonesterified fatty acids (NEFA), β-hydroxybutyrate (BHBA), glucose, insulin, tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, serum amyloid A (SAA), haptoglobin (Hp), and albumin. In control cows, plasma NEFA, IL-1β, IL-6, SAA, and Hp levels increased after calving, but glucose, insulin, and albumin levels decreased after parturition. Se-yeast supplemental cows had lower postpartum concentrations of NEFA, TNF-α, IL-1β, IL-6, SAA, and Hp, and higher postpartum levels of glucose, insulin, and albumin compared with control cows. The results indicate that feeding Se-replete cows a Se-yeast supplement in late pregnancy improves nutrient metabolism and attenuates the inflammatory response after calving.

Arsenic Poisoning: The Risk, Clinical Features and Treatment

Environmental exposure to arsenic, is a major concern in many industrialized countries. Although metals occur naturally in the environment but human activities cause more metals releases and have altered the natural cycling of the elements. These exposures occurs mostly from diet (water and food consumption), inhalation from air and metals related occupational exposure like leaded gasoline, industrial processes such as smelting of lead and its combustion, pottery, boat building, mining industry, exhaust fumes of vehicles, metal based painting, metal containing pipes, battery recycling, grids, arm industry, pigments, printing of books, etc Exposure to arsenic may affect nutrient metabolism and can cause a variety of health effects in human. Cancer, immunotoxicity, hepatotoxicicty, neurotoxicity, nephrotoxicity, brain damage, lungs damage, gastrointestinal distress and haematological alterations are the most frequently documented health implication associated with arsenic intoxication. Consequently, this this paper provide a deep understanding of arsenic, their sources, routes of exposure, the mechanisms of occasioning their toxicity, health implications in human and to identify substances that contribute to overcome their hazardous effects in human.

Methylmercury Induces Metabolic Alterations in Caenorhabditis elegans: Role for C/EBP Transcription Factor.

Methylmercury (MeHg) is a well-known neurotoxicant; however, its role in metabolic diseases has been gaining wider attention. We have previously shown that MeHg causes metabolic alterations in Caenorhabditis elegans, leading to decreased nicotinamide adenine dinucleotide cofactor, mitochondrial dysfunction, and oxidative stress. We were, therefore, interested in whether MeHg also affects nutrient metabolism, particularly lipid homeostasis, which may contribute to the development of metabolic conditions such as obesity or metabolic syndrome (MS). RNA from wild-type worms exposed to MeHg was collected immediately after treatment and used for gene expression analysis by DNA microarray. MeHg differentially regulated 215 genes, 17 genes involved in lipid homeostasis, and 12 genes involved in carbohydrate homeostasis. Of particular interest was cebp-1, the worm ortholog to human C/EBP, a pro-adipogenic transcription factor implicated in MS. MeHg increased the expression of cebp-1 as well as pro-adipogenic transcription factors sbp-1 and nhr-49, triglyceride synthesis enzyme acl-6, and lipid transport proteins vit-2 and vit-6. Concurrent with the altered gene expression, MeHg increased triglyceride levels, lipid storage, and feeding behaviors. Worms expressing mutant cebp-1 were protected from MeHg-induced alterations in lipid content, feeding behaviors, and gene expression, highlighting the importance of this transcription factor in the worm's response to MeHg. Taken together, our data demonstrate that MeHg induces biochemical, metabolic, and behavioral changes in C. elegans that can lead to metabolic dysfunction.

Effects of Vegetation Restoration on the Distribution of Nutrients, Glomalin-Related Soil Protein, and Enzyme Activity in Soil Aggregates on the Loess Plateau, China

Research Highlights: Soil enzymes have a significant impact on the production of glomalin-related soil protein (GRSP), directly and indirectly affecting the nutrient metabolism balance, but there is little available information on ecological stoichiometry in soil aggregates. Background and Objectives: Vegetation restoration changes community structure and species composition in ecosystems, thus changing the physicochemical properties of soil. Soil aggregate is the most basic physical structure of the soil. Therefore, in order to understand dynamic changes in soil aggregate nutrients as vegetation restoration progresses, we set out to investigate the nutrient distribution and utilization in aggregates, and how enzymes respond to the nutrient changes in achieving a nutritional balance along successive stages of vegetation restoration. Materials and Methods: We collected and analyzed soil from plots representing six different stages of a vegetation restoration chronosequence (0, 30, 60, 100, 130, and 160 years) after farmland abandonment on the Loess Plateau, China. We investigated soil nutrient stoichiometry, GRSP, and enzyme stoichiometry in the different successional stages. Results: The results revealed that soil organic carbon, total nitrogen, enzyme activity, and GRSP increased with vegetation recovery age, but not total phosphorus, and not all enzymes reached their maximum in the climax forest community. The easily extractable GRSP/total GRSP ratio was the largest at the shrub community stage, indicating that glomalin degradation was the lowest at this stage. Ecological stoichiometry revealed N-limitation decreased and P-limitation increased with increasing vegetation restoration age. Soil enzymes had a significant impact on the GRSP production, directly and indirectly affecting nutrient metabolism balance. Conclusions: Further study of arbuscular mycorrhizal fungi to identify changes in their category and composition is needed for a better understanding of how soil enzymes affect their release of GRSP, in order to maintain a nutrient balance along successive stages of vegetation restoration.

CXCL12-CXCR4 pathway activates brown adipocytes and induces insulin resistance in CXCR4-deficient mice under high-fat diet

Brown adipose tissue (BAT) plays a role in energy expenditure and is involved in nutrient metabolism. C-X-C chemokine ligand 12 (CXCL12)-CXCR4 pathway regulates the immune, nervous, and cardiovascular systems and affects the adipose tissue. Here, we investigated the role of this pathway as an activator of BAT. Uncoupling protein 1 mRNA and protein levels and oxygen consumption increased in the brown adipocytes treated with 100 nM CXCL12 peptide. CXCL12-mediated upregulation in P38 and extracellular signal-regulated kinase (ERK) levels was reduced by each inhibitor. Thus, the CXCL12-CXCR4 pathway activated the brown adipocytes through P38 and ERK that acted downstream of this pathway. Mice with CXCR4 defects only in the brown adipocytes were generated and fed with high-fat diet (HFD). Body weight and blood glucose after glucose injection increased in these mice. Long-term exposure to HFD deteriorated blood glucose level after glucose injection. Insulin sensitivity was exacerbated in the knockout mice fed with HFD. Serum lipid parameters and CXCL12 level in knockout mice were similar to those in control mice. These results suggest that the CXCL12-CXCR4 pathway induces brown adipocyte activity and affects nutrient metabolism under HFD load.

Effect of a diet containing folate and hazelnut oil capsule on the methylation level of the ADRB3 gene, lipid profile and oxidative stress in overweight or obese women

BackgroundStudies of genes that play an important role in the development of obesity are needed, especially studies focusing on genes that regulate food intake and affect nutrient metabolism. For example, the beta-3 adrenergic receptor (ADRB3) responds to noradrenaline and mediates lipolysis in adipocytes.MethodsThis was a controlled intervention study involving 40 overweight and obese adult women in which food intake, anthropometric measurements, biochemical analyses, and methylation levels of the ADRB3 gene were evaluated before and after intervention. The individuals were randomized into four groups: group 1 (G1) received 300 g of vegetables and legumes containing on average 191 μg/day of folate and 1 hazelnut oil capsule; group 2 (G2) received 300 g of vegetables and legumes containing on average 191 μg/day of folate and 1 placebo capsule; group 3 (G3) received 300 g of vegetables and legumes containing on average 90 μg/day of folate and 1 hazelnut oil capsule; and individuals in group 4 (G4) were only followed-up and maintained their regular dietary habits. Statistical analysis was performed using analysis of variance (ANOVA), Student’s t test and simple regression, using STATA 13 software.ResultsIn the total sample, after the intervention, the women classified as overweight and obese did not present weight loss, and there was a reduction in the methylation levels of the ADRB3 gene and malondialdehyde, as well as an increase in high-density lipoprotein cholesterol and total antioxidant capacity.ConclusionsThe beneficial effect of the intake of a hazelnut capsule on the methylation levels of the ADRB3 gene was demonstrated for the first time.Trial registrationClinicalTrials.gov, NCT 02846025

闽江河口红树林土壤微生物群落对互花米草入侵的响应

PDF HTML阅读 XML下载 导出引用 引用提醒 闽江河口红树林土壤微生物群落对互花米草入侵的响应 DOI: 10.5846/stxb201608141667 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金（31500443）；福建省科技厅引导性项目（2015Y0042）；福建省林业科学研究项目（K8514002A）；福建省教育厅中青年教师科研项目（JA15178） Soil microbial community of mangrove forests and its responses to the invasion of Spartina alterniflora in the Minjiang River Estuary Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:采用磷脂脂肪酸标记法（PLFA）研究外来入侵植物互花米草对闽江河口湿地红树林土壤微生物群落结构的影响，并探讨其主要影响因素。结果表明：从3种不同植被群落土壤（红树林群落MC、红树林-互花米草混生群落MS、互花米草群落SC）共检测到22种PLFA生物标记，MS土壤微生物PLFA生物标记总量明显高于其他植被群落，3种植被群落土壤理化性质和酶活性的变化趋势为：MC > MS > SC，表明互花米草入侵后土壤微生物量增加，而理化性质和酶活性均有明显下降，红树林湿地土壤质量发生了明显退化。3种植被群落土壤中含量最高的PLFA生物标记是16：0，16：1w7c，9Me15：0w，18：1w12c。土壤中特征微生物相对生物量存在明显差异，细菌分布量最大，其次是真菌和放线菌，原生动物分布量最小。群落多样性指数呈相似规律，MS土壤微生物类群多样性指数均小于MC，表明互花米草入侵后土壤微生物群落多样性指数均有下降。通过主成分分析，基本能区分出3种不同植被群落微生物群落的特征。土壤理化性质、酶活性间存在相关性，有机碳、全氮、蔗糖酶、过氧化氢酶与革兰氏阴性菌、放线菌呈显著或极显著正相关。研究结果表明互花米草入侵在一定程度上具有影响红树林群落土壤营养代谢循环的潜力，特别是关于碳、氮、磷等的循环及酶活性，改变部分有利于自身生长的土壤环境相关的微生物类群含量，竞争有利环境，迅速扩张实现入侵。 Abstract:In the present study, soil microbial communities of mangrove forests and its responses to the invasion of Spartina alterniflora were analyzed using phospholipid fatty acid analysis (PLFA). Soil physic-chemical properties and enzyme activities were measured in the Minjiang River Estuary. The results showed that: There were 22 PLFAs that were significantly different in soil samples from mangrove communities (MC), Mangrove-S. alterniflora (MS), and S. alterniflora communities (SC). The MS soil exhibited richer PLFAs than the other vegetation types. The physic-chemical properties and enzyme activities in soils of different vegetation communities were in the order of MC > MS > SC. Following the invasion of S. alterniflora, the soil microbial biomass of mangrove communities increased, and the physic-chemical properties, enzyme activities significantly decreased, and the quality of mangrove wetland soil was degraded. The PLFAs biomarkers of three species with the highest contents were 16:0, 16:1w7c, 9Me15:0w, and 18:1w12c. There was a significant difference in the relative biomass of soil microbial biomass. Bacteria exhibited the richest distribution, followed by fungus, actinomycetes, and protozoans. Community diversity indices showed a similar pattern, MS soil microbial community diversity indexes were less than those of MC. The soil microbial community diversity indexes decreased following the invasion of S. alterniflora. Principal component analysis was able to distinguish the characteristics of microbial communities in different vegetation communities. The soil physic-chemical properties were closely correlated with enzyme activities, and SOC, TN, sucrose, and catalase were significantly correlated with the PLFAs of gram-positive bacteria and actinomycetes. The results of this study showed that the invasion of S. alterniflora has the potential to affect nutrient metabolism in the mangrove community, especially with regard to the C, N and P cycles, and the enzyme activities. S. alterniflora can change the microbial biomass to create favorable soil environments for their growth to achieve the rapid invasion. 参考文献 相似文献 引证文献

The Effects of Childhood Malnutrition on DNA Methylation in Adulthood

Insults during critical periods of development could result in epigenetic changes affecting health and behavioral outcomes throughout the lifespan. To address the epigenetic effects of childhood malnutrition we assessed genome-wide DNA methylation levels in previously malnourished and healthy control adults (age 33-47 yrs). The Barbados Nutrition Study is a 47-year longitudinal study, following individuals with histories of malnutrition limited to the first year of life - who were enrolled in an intervention program through 12 years of age – and healthy controls from the same classrooms and neighborhoods. Using the Illumina 450K array and a stringent statistical analysis with age, gender and cell composition correction, we report differences in DNA methylation between previously malnourished (n=52) and controls (n=44). Differentially Methylated Regions (DMRs) were identified using a 1 kb sliding window approach, with significant DMRs comprising multiple CpGs selected at FDR<0.05. In total we identified 303 DMRs, including several genes with known roles in regulating metabolism. Loci with the largest differences between Malnourished and Control (as measured by methylation values) included GNAS, an imprinted gene regulating metabolism and obesity. Our data show that epigenomic changes in genes affecting nutrient metabolism are detected in white blood cells of adults exposed to a single episode of malnutrition in early childhood. Acknowledgements: This research was supported by NIH grant HD060986 (JRG) and R01MH086509 (SA).

Joint association of genome-wide association study-identified susceptibility loci and dietary patterns in risk of renal cell carcinoma among non-Hispanic whites.

Dietary factors may affect risk of renal cell carcinoma (RCC). In an ongoing case-control study of RCC initiated in Houston, Texas, in 2002, we identified 3 empirically derived dietary patterns: "fruits and vegetables," "American/Western," and "Tex-Mex." Among 659 RCC cases and 699 controls, we evaluated associations of these dietary patterns with RCC risk and whether the associations varied by obesity status, smoking status, physical activity level, history of hypertension, and genetic variants previously identified via genome-wide association studies. Among persons in the highest categories of adherence versus the lowest, the "fruits and vegetables" dietary pattern was associated with an approximately 50% lower RCC risk (Ptrend < 0.001), while "American/Western" dietary pattern scores were positively associated with a 2-fold higher risk (Ptrend < 0.001). We observed synergistic interaction between the American/Western pattern and hypertension status: The odds ratio (highest tertile vs. lowest) among persons with hypertension was 2.23 (95% confidence interval: 1.43, 3.45), as compared with 1.76 (95% confidence interval: 1.16, 2.70) among persons without hypertension (additive Pinteraction = 0.01). A variant (rs718314) in the inositol 1,4,5-trisphosphate receptor, type 2 gene (ITPR2) was found to interact with the American/Western dietary pattern in relation to RCC risk (additive Pinteraction = 0.03). ITPR2 has been shown to affect nutrient metabolism and central obesity. Dietary patterns, genetic variants, and host characteristics may individually and jointly influence susceptibility to RCC.

Organ Damage and Hepatic Lipid Accumulation in Carp (Cyprinus carpio L.) after Feed-Borne Exposure to the Mycotoxin, Deoxynivalenol (DON)

Deoxynivalenol (DON) frequently contaminates animal feed, including fish feed used in aquaculture. This study intends to further investigate the effects of DON on carp (Cyprinus carpio L.) at concentrations representative for commercial fish feeds. Experimental feeding with 352, 619 or 953 μg DON kg−1 feed resulted in unaltered growth performance of fish during six weeks of experimentation, but increased lipid peroxidation was observed in liver, head kidney and spleen after feeding of fish with the highest DON concentration. These effects of DON were mostly reversible by two weeks of feeding the uncontaminated control diet. Histopathological scoring revealed increased liver damage in DON-treated fish, which persisted even after the recovery phase. At the highest DON concentration, significantly more fat, and consequently, increased energy content, was found in whole fish body homogenates. This suggests that DON affects nutrient metabolism in carp. Changes of lactate dehydrogenase (LDH) activity in kidneys and muscle and high lactate levels in serum indicate an effect of DON on anaerobic metabolism. Serum albumin was reduced by feeding the medium and a high dosage of DON, probably due to the ribotoxic action of DON. Thus, the present study provides evidence of the effects of DON on liver function and metabolism.

Luminal chemosensing in the duodenal mucosa.

The upper gastrointestinal (GI) mucosa is exposed to endogenous and exogenous chemicals, including gastric acid, CO₂ and nutrients. Mucosal chemical sensors are necessary to exert physiological responses such as secretion, digestion, absorption and motility. We propose the mucosal chemosensing system by which luminal chemicals are sensed to trigger mucosal defence mechanisms via mucosal acid sensors and taste receptors. Luminal acid/CO₂ is sensed via ecto- and cytosolic carbonic anhydrases and ion transporters in the epithelial cells and via acid sensors on the afferent nerves in the duodenum and the oesophagus. Gastric acid sensing is differentially mediated via endocrine cell acid sensors and afferent nerves. Furthermore, a luminal l-glutamate signal is mediated via epithelial l-glutamate receptors, including metabotropic glutamate receptors and taste receptor 1 family heterodimers, with activation of afferent nerves and cyclooxygenase, whereas luminal Ca²(+) is differently sensed via the calcium-sensing receptor in the duodenum. These luminal chemosensors help to activate mucosal defence mechanisms in order to maintain the mucosal integrity and physiological responses of the upper GI tract. Stimulation of luminal chemosensing in the upper GI mucosa may prevent mucosal injury, affect nutrient metabolism and modulate sensory nerve activity.

The Addition of Choline to Parenteral Nutrition

Choline is a quaternary amine endogenously synthesized from the amino acid methionine or absorbed via the portal circulation. It is ubiquitous in the diet, although it has a greater presence in organ meats. Choline is an essential component of all cell membranes, and has been considered a required dietary nutrient since 1998 by the US Institute of Medicine's Food and Nutrition Board. Choline is necessary for DNA repair, mediated by its role as a methyl donor. It also serves as the precursor for the neurotransmitter acetylcholine. Evidence has accumulated that hepatic steatosis, which occurs during parenteral nutrition therapy, develops as a result of choline deficiency because endogenous production of choline from parenterally infused methionine is deficient. In addition, memory deficits and skeletal muscle abnormalities have been described, and choline deficiency appears to activate cellular apoptosis. Provision of intravenous choline ameliorates hepatic steatosis associated with parenteral nutrition infusion.

Astaxanthin improves muscle lipid metabolism in exercise via inhibitory effect of oxidative CPT I modification

Intracellular redox balance may affect nutrient metabolism in skeletal muscle. Astaxanthin, a carotenoid contained in various natural foods, exerts high antioxidative capacity in the skeletal muscles. The present study investigated the effect of astaxanthin on muscle lipid metabolism in exercise. ICR mice (8 weeks old) were divided into four different groups: sedentary, sedentary treated with astaxanthin, running exercise, and exercise treated with astaxanthin. After 4 weeks of treatment, exercise groups performed treadmill running. Astaxanthin increased fat utilization during exercise compared with mice on a normal diet with prolongation of the running time to exhaustion. Colocalization of fatty acid translocase with carnitine palmitoyltransferase I (CPT I) in skeletal muscle was increased by astaxanthin. We also found that hexanoyl-lysine modification of CPT I was increased by exercise, while astaxanthin prevented this increase. In additional experiment, we found that astaxanthin treatment accelerated the decrease of body fat accumulation with exercise training. Our results suggested that astaxanthin promoted lipid metabolism rather than glucose utilization during exercise via CPT I activation, which led to improvement of endurance and efficient reduction of adipose tissue with training.

Improved weight management using genetic information to personalize a calorie controlled diet

BackgroundGene-environment studies demonstrate variability in nutrient requirements depending upon individual variations in genes affecting nutrient metabolism and transport. This study investigated whether the inclusion of genetic information to personalize a patient's diet (nutrigenetics) could improve long term weight management.MethodsPatients with a history of failures at weight loss were offered a nutrigenetic test screening 24 variants in 19 genes involved in metabolism. 50 patients were in the nutrigenetic group and 43 patients attending the same clinic were selected for comparison using algorithms to match the characteristics: age, sex, frequency of clinical visits and BMI at initial clinic visit. The second group of 43 patients did not receive a nutrigenetic test. BMI reduction at 100 and > 300 days and blood fasting glucose were measured.ResultsAfter 300 days of follow-up individuals in the nutrigenetic group were more likely to have maintained some weight loss (73%) than those in the comparison group (32%), resulting in an age and gender adjusted OR of 5.74 (95% CI 1.74–22.52). Average BMI reduction in the nutrigenetic group was 1.93 kg/m2(5.6% loss) vs. an average BMI gain of 0.51 kg/m2(2.2% gain) (p < 0.023). Among patients with a starting blood fasting glucose of > 100 mg/dL, 57% (17/30) of the nutrigenetic group but only 25% (4/16) of the non-tested group had levels reduced to < 100 mg/dL after > 90 days of weight management therapy (OR for lowering glucose to < 100 mg/dL due to diet = 1.98 95%CI 1.01, 3.87, p < 0.046).ConclusionAddition of nutrigenetically tailored diets resulted in better compliance, longer-term BMI reduction and improvements in blood glucose levels.