Metabonomic Analysis Reveals the CCl₄-Induced Systems Alterations for Multiple Rat Organs

CCl₄-induced metabonomic changes have been extensively studied for mammalian liver, and such changes have not been reported for other organs. To investigate the CCl₄ effects on other organs, we analyzed the CCl₄-induced metabonomic changes in rat kidney, lung, and spleen using ¹H NMR-based metabonomics approaches with complementary information on serum clinical chemistry and histopathology. We found that acute CCl₄ exposure caused significant level elevation for creatine and decline for glucose, taurine, trimethylamine, uridine, and adenosine in rat kidney. CCl₄-treatment also induced elevation of amino acids (isoleucine, leucine, valine, threonine, alanine, lysine, ornithine, methionine, tyrosine, phenylalanine, and histidine), creatine, and betaine in rat lung together with depletion of glycogen, glucose, taurine, glycine, and hypoxanthine. Furthermore, CCl₄ caused elevation of lactate, alanine, betaine, and uracil in rat spleen accompanied with decline for glucose, choline, and hypoxanthine. These observations indicated that CCl₄ caused oxidative stresses to multiple rat organs and alterations of their functions including renal osmotic regulations, accelerated glycolysis, and protein and nucleotide catabolism. These findings provide essential information on CCl₄ toxicity to multiple rat organs and suggest that systems toxicological views are required for metabonomic studies of toxins by taking many other organs into consideration apart from so-called targeted ones

Age-Related Topographical Metabolic Signatures for the Rat Gastrointestinal Contents

Symbiotic gut microbiota is essential for mammalian physiology and analyzing the metabolite compositions of gastrointestinal contents is vital for understanding the microbiome–host interactions. To understand the developmental dependence of the topographical metabolic signatures for the rat gastrointestinal contents, we systematically characterized the metabolite compositional variations of the contents in rat jejunum, ileum, cecum, and colon for two age-groups using ¹H NMR spectroscopy and multivariate analysis. Significant topographical metabolic variations were present for the jejunal, ileal, cecal, colonic contents, and feces, reflecting the absorption functions for each intestinal region and the gut microbiota therein. The concentrations of amino acids, lactate, creatine, choline, bile acids, uracil and urocanate decreased drastically from jejunal to ileal contents followed with steady decreases from cecal content to feces. Short-chain fatty acids (SCFAs) and arabinoxylan-related carbohydrates had highest levels in cecal content and feces, respectively. Such topographical metabolic signatures for the intestinal contents varied with animal age highlighted by the level changes for lactate, choline, taurine, amino acids, carbohydrates, keto-acids, and SCFAs. These findings provided essential information for the topographical metabolic variations in the gastrointestinal tract and demonstrated metabolic profiling as a useful approach for understanding host–microbiome interactions and functional status of the gastrointestinal regions

Gallic Acid Intake Induces Alterations to Systems Metabolism in Rats

Gallic acid (GA) and its metabolites are polyphenolic compounds present in daily diets and herbal medicines. To understand the GA effects on the endogenous metabolism of mammals, we systematically analyzed the metabonomic responses of rat plasma, liver, urine, and feces to a single GA dosage of 120 and 600 mg/kg, which were below the no-obvious-adverse-effect-level of 1 g/kg for rats. Clinical chemistry and histopathological assessments were conducted to provide complementary information. Our results showed that GA intake induced significant metabonomic changes in multiple rat biological matrices. Such changes were more outstanding in liver than in the other matrices and clearly showed dose- and time-dependence. The results suggested GA-induced promotion of oxidative stress as the major effect. High-dose GA caused significant metabolic changes involving glycogenolysis, glycolysis, TCA cycle, and metabolism of amino acids, purines, and pyrimidines, together with gut microbiota functions. Low-dose GA only caused some urinary metabonomic changes and to a much less degree. The GA-induced liver metabonomic changes were not completely recoverable within a week, although such recovery completed in plasma, urine, and feces within 80 h. These findings provided new essential information on the effects of dietary polyphenols and demonstrated the great potential of this nutrimetabonomics approach

Effect of Carotene and Lycopene on the Risk of Prostate Cancer: A Systematic Review and Dose-Response Meta-Analysis of Observational Studies

<div><p>Background</p><p>Many epidemiologic studies have investigated the association between carotenoids intake and risk of Prostate cancer (PCa). However, results have been inconclusive.</p><p>Methods</p><p>We conducted a systematic review and dose-response meta-analysis of dietary intake or blood concentrations of carotenoids in relation to PCa risk. We summarized the data from 34 eligible studies (10 cohort, 11 nested case-control and 13 case-control studies) and estimated summary Risk Ratios (RRs) and 95% confidence intervals (CIs) using random-effects models.</p><p>Results</p><p>Neither dietary β-carotene intake nor its blood levels was associated with reduced PCa risk. Dietary α-carotene intake and lycopene consumption (both dietary intake and its blood levels) were all associated with reduced risk of PCa (RR for dietary α-carotene intake: 0.87, 95%CI: 0.76–0.99; RR for dietary lycopene intake: 0.86, 95%CI: 0.75–0.98; RR for blood lycopene levels: 0.81, 95%CI: 0.69–0.96). However, neither blood α-carotene levels nor blood lycopene levels could reduce the risk of advanced PCa. Dose-response analysis indicated that risk of PCa was reduced by 2% per 0.2mg/day (95%CI: 0.96–0.99) increment of dietary α-carotene intake or 3% per 1mg/day (95%CI: 0.94–0.99) increment of dietary lycopene intake.</p><p>Conclusions</p><p>α-carotene and lycopene, but not β-carotene, were inversely associated with the risk of PCa. However, both α-carotene and lycopene could not lower the risk of advanced PCa.</p></div

Enhanced Green Fluorescent Protein Transgenic Expression <i>In Vivo</i> Is Not Biologically Inert

Enhanced green fluorescent protein (EGFP) is a widely used biological reporter. However, the effects of EGFP expression <i>in vivo</i> are still unclear. To investigate the effects of EGFP transgenic expression <i>in vivo</i>, we employed an NMR-based metabonomics method to analyze the metabonome of EGFP transgenic mice. The results show that the metabonomes of urine, liver, and kidney of the EGFP transgenic mice are different from their wild-type counterparts. The EGFP mice expressed high levels of urinary 3-ureidopropionate, which is due to the down-regulated transcriptional level of β-ureidopropionase. The expression of EGFP <i>in vivo</i> also affects other metabolic pathways, including nucleic acid metabolism, energy utilization, and amino acids catabolism. These findings indicate that EGFP transgenic expression is not as inert as has been considered. Our investigation provides a holistic view on the effect of EGFP expression <i>in vivo</i>, which is useful when EGFP is employed as a functional biological indicator. Our work also highlights the potential of a metabonomics strategy in studying the association between molecular phenotypes and gene function

Systemic Responses of Mice to Dextran Sulfate Sodium-Induced Acute Ulcerative Colitis Using ¹H NMR Spectroscopy

The interplay between genetic mutation and environmental factors is believed to contribute to the etiology of inflammatory bowel disease (IBD). While focused attention has been paid to the aforementioned research, time-specific and organ-specific metabolic changes associated with IBD are still lacking. Here, we induced acute ulcerative colitis in mice by providing water containing 3% dextran sulfate sodium (DSS) for 7 days and investigated the metabolic changes of plasma, urine, and a range of biological tissues by employing a ¹H nuclear magnetic resonance (NMR)-based metabonomics approach with complementary information on serum clinical chemistry and histopathology. We found that DSS-induced acute ulcerative colitis leads to significant elevations in the levels of amino acids in plasma and decreased levels in the membrane-related metabolites and a range of nucleotides, nucleobases, and nucleosides in the colon. In addition, acute-colitis-induced elevations in the levels of nucleotides in the liver were observed, accompanied by reduced levels of glucose. DSS-induced acute colitis also resulted in increased levels of oxidized glutathione and attenuated levels of taurine in the spleen. Furthermore, acute colitis resulted in depletion in the levels of gut microbial cometabolites in urine along with an increase in citric acid cycle intermediates. These findings suggest that DSS-induced acute colitis causes a disturbance of lipid and energy metabolism, damage to the colon and liver, a promoted antioxidative and anti-inflammatory response, and perturbed gut microbiotal communities. The information obtained here provided details of the time-dependent and holistic metabolic changes in the development of the DSS-induced acute ulcerative colitis, which could be useful in discovery of novel therapeutic targets for management of IBD

CcpA-Mediated Enhancement of Sugar and Amino Acid Metabolism in <i>Lysinibacillus sphaericus</i> by NMR-Based Metabolomics

<i>Lysinibacillus sphaericus</i> is a bacterium incapable of metabolizing sugars with the sole exception of <i>N</i>-acetylglucosamine. To unravel the regulatory role of catabolite control protein A (CcpA) in the sugar metabolism of <i>L. sphaericus</i>, a <i>ccpA</i> deficient mutant was constructed by homologous recombination. The mutant showed growth deficiency and a low efficiency of carbon and energy utilization. NMR spectroscopy in combination with multivariate data analysis revealed that the metabolome of <i>L. sphaericus</i> was dominated by 25 metabolites mainly including amino acids, carbohydrate derivatives and organic acids, and that the mutation of the <i>ccpA</i> gene caused significant reduction of leucine, valine, alanine, threonine, glutamate, lysine, d-ornithine, tyrosine, uridine 5′-diphospho-<i>N</i>-acetlyglucosamine formate, fumarate, phenylalanine, aspartate, asparagine, and acetate but elevation of ribose-5-phosphate, and uracil. Furthermore, the networks of CcpA-mediated regulation based on the metabolome were constructed by arrangement of significantly decreasing or increasing metabolites. The network map suggests CcpA regulates and promotes sugar and amino acid metabolism of <i>L. sphaericus</i>

Integrative Transcriptomic and Metabonomic Molecular Profiling of Colonic Mucosal Biopsies Indicates a Unique Molecular Phenotype for Ulcerative Colitis

Ulcerative colitis is the most prevailing entity of several disorders under the umbrella term inflammatory bowel disease, with potentially serious symptoms and devastating consequences for affected patients. The exact molecular etiology of ulcerative colitis is not yet revealed. In this study, we characterized the molecular phenotype of ulcerative colitis through transcriptomic and metabonomic profiling of colonic mucosal biopsies from patients and controls. We have characterized the extent to which metabonomic and transcriptomic molecular phenotypes are associated with ulcerative colitis versus controls and other disease-related phenotypes such as steroid dependency and age at diagnosis, to determine if there is evidence of enrichment of differential expression in candidate genes from genome-wide association studies and if there are particular pathways influenced by disease-associated genes. Both transcriptomic and metabonomic data have previously been shown to predict the clinical course of ulcerative colitis and related clinical phenotypes, indicating that molecular phenotypes reveal molecular changes associated with the disease. Our analyses indicate that variables of both transcriptomics and metabonomics are associated with disease case and control status, that a large proportion of transcripts are associated with at least one metabolite in mucosal colonic biopsies, and that multiple pathways are connected to disease-related metabolites and transcripts

Dose-response relation plots between carotenoids consumption and risk of PCa.

<p>(A) Dietary lycopene intake(mg/day) and risk of PCa; (B) Blood lycopene levels (ug/dl) and risk of PCa; (C) Dietary α-carotene intake(mg/day) and risk of PCa. These relationships were estimated by using random-effects metaregression. Dotted lines represent the 95% CIs for the fitted trend.</p

Characteristics of included studies.

<p>Abbreviations: NCCS, nested case-control study; CCS, case-control study; SD, standard deviation; T, tertile; Q, quartile/quintile; BMI, body mass index; NSAIDs, non-steroidal anti-inflammatory drugs; FHPC, family history of prostate cancer; NR, not reported; NA, not accessible.</p><p>^aDerived from the slogan of a campaign, “Give us a CLUE to cancer.”</p><p>^bIndicated interquartile range(IQR).</p><p>Characteristics of included studies.</p