An investigation of the plasma and urinary metabolite profiles of the hepatotoxin methapyrilene in the male Wistar rat.

BackgroundThe human metabolome is influenced by various intrinsic and extrinsic factors. A precondition to identify such biomarkers is the comprehensive understanding of the composition and variability of the metabolome of healthy humans. Sample handling aspects have an important impact on the composition of the metabolome; therefore, it is crucial for any metabolomics study to standardize protocols on sample collection, preanalytical sample handling, storage, and analytics to keep the nonbiological variability as low as possible.ObjectiveThe main objective of the KarMeN study is to analyze the human metabolome in blood and urine by targeted and untargeted metabolite profiling (gas chromatography-mass spectrometry [GC-MS], GC×GC-MS, liquid chromatography-mass spectrometry [LC-MS/MS], and1H nuclear magnetic resonance [NMR] spectroscopy) and to determine the impact of sex, age, body composition, diet, and physical activity on metabolite profiles of healthy women and men. Here, we report the outline of the study protocol with special regard to all aspects that should be considered in studies applying metabolomics.MethodsHealthy men and women, aged 18 years or older, were recruited. In addition to a number of anthropometric (height, weight, body mass index, waist circumference, body composition), clinical (blood pressure, electrocardiogram, blood and urine clinical chemistry) and functional parameters (lung function, arterial stiffness), resting metabolic rate, physical activity, fitness, and dietary intake were assessed, and 24-hour urine, fasting spot urine, and plasma samples were collected. Standard operating procedures were established for all steps of the study design. Using different analytical techniques (LC-MS, GC×GC-MS,1H NMR spectroscopy), metabolite profiles of urine and plasma were determined. Data will be analyzed using univariate and multivariate as well as predictive modeling methods.ResultsThe project was funded in 2011 and enrollment was carried out between March 2012 and July 2013. A total of 301 volunteers were eligible to participate in the study. Metabolite profiling of plasma and urine samples has been completed and data analysis is currently underway.ConclusionsWe established the KarMeN study applying a broad set of clinical and physiological examinations with a high degree of standardization. Our experimental approach of combining scheduled timing of examinations and sampling with the multiplatform approach (GC×GC-MS, GC-MS, LC-MS/MS, and1H NMR spectroscopy) will enable us to differentiate between current and long-term effects of diet and physical activity on metabolite profiles, while enabling us at the same time to consider confounders such as age and sex in the KarMeN study.Trial RegistrationGerman Clinical Trials Register DRKS00004890; https://drks-neu.uniklinik-freiburg.de/drks_web/navigate.do? navigationId=trial.HTML&TRIAL_ID=DRKS00004890 (Archived by WebCite at http://www.webcitation.org/6iyM8dMtx)

Mongolian sheep are an indigenous ruminant raised for wool and meat production in China. The gut microbial community plays an important role in animal performance and metabolism. The objective of this study was to investigate the effects of two feeding regimens on the diversity and composition of gut microbiota and metabolite profiles of feces and plasma from Mongolian sheep. A total of 20 Mongolian sheep were assigned to one of two feeding regimens: free grazing (FG) and barn confinement (BC). When samples were collected, the average live weights of the sheep were 31.28 ± 1.56 kg and 34.18 ± 1.87 kg for the FG and BC groups, respectively. At the genus level, the FG group showed higher levels of Bacteroides, RC9_gut_group, Alistipes, Phocaeicola, Barnesiella, and Oscillibacter, and lower levels of Succinivibrio, Treponema, and Prevotella, compared to the BC group. The butyric acid content in feces was lower in the FG group (P > 0.05). Higher levels of palmitic acid, oleic acid, alpha-linolenic acid, L-carnitine, L-citrulline, and L-histidine, and lower levels of L-tyrosine, L-phenylalanine, and L-kynurenine were found in the plasma of the FG sheep. Moreover, there were substantial associations between several gut microbiota genera and alterations in feces and plasma metabolites especially those involved in the metabolism of butyric acid, linolenic acid, and L-tyrosine. Feeding regimens can not only influence the composition of gut microbiota, but also alter metabolic homeaostasis in sheep.

IntroductionTraditional herbal medicine (THM) contains a vast number of natural compounds with varying degrees of pharmacological activity. To elucidate the mode of action, comprehensive metabolite profiling in the plasma before and after administration of THM is essential.ObjectiveThe aim of this study was to explore and identify/annotate converted metabolites after administration of THM in humans.MethodsWe performed untargeted metabolome analysis of human plasma collected before and after administration of maoto (ma-huang-tang), a traditional Japanese Kampo medicine. Maoto-derived metabolites were then selected and annotated following the DAC-Met strategy, which is an annotation method that uses mass differences of major metabolic reactions among the detected peaks and a differential network analysis.ResultsAbout 80% of maoto-derived components were found to be converted forms. Following DAC-Met, the structures of 15 previously unidentified metabolites were determined, and five of these were later confirmed with authentic standards. Using published literature, we also reconstructed the metabolic pathway of maoto components in humans. A kinetic time-course analysis revealed their diverse kinetic profiles.ConclusionThe results demonstrated that time-resolved comprehensive metabolite profiling in plasma using the DAC-Met strategy is highly useful for elucidating the complex nature of THM.

Nut skins are considered to be a rich source of polyphenols and may be partially responsible for the numerous health effects associated with nut consumption. However, more bioavailability studies of nut skin polyphenols are needed to understand the health effects derived from nut consumption. The aim of the present study was to determine the profiles of both phase II and microbial-derived phenolic metabolites in plasma and urine samples before and after the intake of almond skin polyphenols by healthy human subjects (n = 2). Glucuronide, O-methyl glucuronide, sulfate, and O-methyl sulfate derivatives of (epi)catechin, as well as the glucuronide conjugates of naringenin and glucuronide and sulfate conjugates of isorhamnetin, were detected in plasma and urine samples after consumption of almond skin polyphenols. The main microbial-derived metabolites of flavanols, such as 5-(dihydroxyphenyl)-gamma-valerolactone and 5-(hydroxymethoxyphenyl)-gamma-valerolactone, were also detected in their glucuronide and sulfate forms. In addition, numerous metabolites derived from further microbial degradation of hydroxyphenylvalerolactones, including hydroxyphenylpropionic, hydroxyphenylacetic, hydroxycinnamic, hydroxybenzoic, and hydroxyhippuric acids, registered major changes in urine after the consumption of almond skin polyphenols. The urinary excretion of these microbial metabolites was estimated to account for a larger proportion of the total polyphenol ingested than phase II metabolites of (epi)catechin, indicating the important role of intestinal bacteria in the metabolism of highly polymerized almond skin polyphenols. To the authors' knowledge this study constitutes the most complete report of the absorption of almond skin polyphenols in humans.

Validated biomarkers of food intake (BFIs) have recently been suggested as a useful tool to assess adherence to dietary guidelines or compliance in human dietary interventions. Although many new candidate biomarkers have emerged in the last decades for different foods from metabolic profiling studies, the number of comprehensively validated biomarkers of food intake is limited. Apples are among the most frequently consumed fruits and a rich source of polyphenols and fibers, an important mediator for their health-protective properties. Using an untargeted metabolomics approach, we aimed to identify biomarkers of long-term apple intake and explore how apples impact on the human plasma and urine metabolite profiles. Forty mildly hypercholesterolemic volunteers consumed two whole apples or a sugar and energy-matched control beverage, daily for 8weeks in a randomized, controlled, crossover intervention study. The metabolome in plasma and urine samples was analyzed via untargeted metabolomics. We found 61 urine and 9 plasma metabolites being statistically significant after the whole apple intake compared to the control beverage, including several polyphenol metabolites that could be used as BFIs. Furthermore, we identified several endogenous indole and phenylacetyl-glutamine microbial metabolites significantly increasing in urine after apple consumption. The multiomic dataset allowed exploration of the correlations between metabolites modulated significantly by the dietary intervention and fecal microbiota species at genus level, showing interesting interactions between Granulicatella genus and phenyl-acetic acid metabolites. Phloretin glucuronide and phloretin glucuronide sulfate appeared promising biomarkers of apple intake; however, robustness, reliability and stability data are needed for full BFI validation. The identified apple BFIs can be used in future studies to assess compliance and to explore their health effects after apple intake. Moreover, the identification of polyphenol microbial metabolites suggests that apple consumption mediates significant gut microbial metabolic activity which should be further explored.

Capmatinib (INC280), a highly selective and potent inhibitor of the MET receptor tyrosine kinase, has demonstrated clinically meaningful efficacy and a manageable safety profile in patients with advanced non-small-cell lung cancer harboring MET exon 14-skipping mutations. We investigated the absorption, distribution, metabolism, and excretion of capmatinib in six healthy male volunteers after a single peroral dose of 600 mg 14C-labeled capmatinib. The mass balance, blood and plasma radioactivity, and plasma capmatinib concentrations were determined along with metabolite profiles in plasma, urine, and feces. The metabolite structures were elucidated using mass spectrometry and comparing with reference compounds. The parent compound accounted for most of the radioactivity in plasma (42.9% ± 2.9%). The extent of oral absorption was estimated to be 49.6%; the Cmax of capmatinib in plasma was reached at 2 hours (median time to reach Cmax). The apparent mean elimination half-life of capmatinib in plasma was 7.84 hours. Apparent distribution volume of capmatinib during the terminal phase was moderate-to-high (geometric mean 473 l). Metabolic reactions involved lactam formation, hydroxylation, N-dealkylation, formation of a carboxylic acid, hydrogenation, N-oxygenation, glucuronidation, and combinations thereof. M16, the most abundant metabolite in plasma, urine, and feces was formed by lactam formation. Absorbed capmatinib was eliminated mainly by metabolism and subsequent biliary/fecal and renal excretion. Excretion of radioactivity was complete after 7 days. CYP phenotyping demonstrated that CYP3A was the major cytochrome P450 enzyme subfamily involved in hepatic microsomal metabolism, and in vitro studies in hepatic cytosol indicated that M16 formation was mainly catalyzed by aldehyde oxidase. SIGNIFICANCE STATEMENT: The absorption, distribution, metabolism, and excretion of capmatinib revealed that capmatinib had substantial systemic availability after oral administration. It was also extensively metabolized and largely distributed to the peripheral tissue. Mean elimination half-life was 7.84 hours. The most abundant metabolite, M16, was formed by imidazo-triazinone formation catalyzed by cytosolic aldehyde oxidase. Correlation analysis, specific inhibition, and recombinant enzymes phenotyping demonstrated that CYP3A is the major enzyme subfamily involved in the hepatic microsomal metabolism of [14C]capmatinib.

Lenacapavir (LEN) is a novel, first-in-class, multistage, selective inhibitor of human immunodeficiency virus type 1 (HIV-1) capsid function recently approved for the treatment of HIV-1 infection in heavily treatment-experienced adults with multidrug-resistant HIV-1 infection. The purpose of this multicohort study was to evaluate the pharmacokinetics, metabolism, excretion, safety, and tolerability of LEN following a single intravenous (IV) infusion of 10 mg LEN or 20 mg [14C]LEN in healthy participants. Twenty-one healthy adult participants were enrolled into the study and received either a single IV dose of 10 mg LEN (n = 8 active, n = 3 placebo; cohort 1) or a single IV dose of 20 mg [14C]LEN containing 200 µCi (n = 10; cohort 2). Blood, urine, and feces samples (when applicable) were collected after dosing, and radioactivity (cohort 2) was assessed using liquid scintillation counting in both plasma and excreta. LEN in plasma was quantified by liquid chromatography (LC) tandem mass spectroscopy (MS/MS) method bioanalysis. Metabolite profiling in plasma and excreta were performed using LC-fraction collect (FC)-high-resolution MS and LC-FC-accelerator mass spectrometry in plasma. Between the 10 mg and 20 mg doses of LEN, the observed plasma exposure of LEN doubled, while the elimination half-life was similar. Following administration of 20 mg [14C]LEN (200 µCi), the mean cumulative recovery of [14C] radioactivity was 75.9% and 0.24% from feces and urine, respectively. The mean whole [14C] blood-to-plasma concentration ratio was 0.5-0.7, which showed a low distribution of LEN to red blood cells. Intact LEN was the predominant circulating species in plasma (representing 68.8% of circulating radioactivity), and no single metabolite contributed to >10% of total radioactivity exposure through 1176 h postdose. Similarly, intact LEN was the most abundant component (32.9% of administered dose; 75.9% of recovered dose) measured in feces, with metabolites accounting for trace amounts. These results suggest metabolism of LEN is not a primary pathway of elimination. Of the metabolites observed in the feces, the three most abundant metabolites were direct phase 2 conjugates (glucuronide, hexose, and pentose conjugates), with additional metabolites formed to a lesser extent via other pathways. The administered LEN IV doses were generally safe and well-tolerated across participants in this study. The results of this mass balance study indicated that LEN was majorly eliminated as intact LEN via the feces. The renal pathway played a minor role in LEN elimination (0.24%). In addition, no major circulating metabolites in plasma or feces were found, indicating minimal metabolism of LEN.

Salmonella Typhi is the causative agent of typhoid. Typhoid is diagnosed by blood culture, a method that lacks sensitivity, portability and speed. We have previously shown that specific metabolomic profiles can be detected in the blood of typhoid patients from Nepal (Näsström et al., 2014). Here, we performed mass spectrometry on plasma from Bangladeshi and Senegalese patients with culture confirmed typhoid fever, clinically suspected typhoid, and other febrile diseases including malaria. After applying supervised pattern recognition modelling, we could significantly distinguish metabolite profiles in plasma from the culture confirmed typhoid patients. After comparing the direction of change and degree of multivariate significance, we identified 24 metabolites that were consistently up- or down regulated in a further Bangladeshi/Senegalese validation cohort, and the Nepali cohort from our previous work. We have identified and validated a metabolite panel that can distinguish typhoid from other febrile diseases, providing a new approach for typhoid diagnostics.

1. In healthy male volunteers, the absorption, metabolite profiles and excretion of Cbenidipine hydrochloride, a new Ca antagonist, were investigated after oral administration at a dose of 8 mg. 2. C-benidipine hydrochloride was rapidly absorbed, and the plasma concentration of radioactivity and unchanged drug reached a maximum of 71 2 ng eq. ml at 1 1 h and 2 56 ng ml at 0 6 h respectively, and then declined bi-exponentially. The half-life in the elimination phase was 14 7 and 5 3 h respectively. AUC of unchanged drug was low, about 1% of that of radioactivity. 3. Five days after administration,36 4% of the administered radioactivity was excreted in urine and 58 9% in faeces. 4. The metabolite profiles in plasma, urine and faeces were analysed by hplc. At 1 h after administration the predominant metabolites in plasma were M9 and M2, which accounted for 13 8 and 8 2% of the radioactivity respectively, whereas unchanged drug represented 1 2%. Predominant metabolites in urine 12 h after administration were M3 andM8,whichaccountedfor2 22and2 21%oftheadministeredradioactivityrespectively. Metabolites excreted in faeces 120 h after administration were very complex and poorly separated by hplc and could not be characterized: unchanged drug was not detected in the faeces.

Salmonella Typhi is the causative agent of typhoid. Typhoid is diagnosed by blood culture, a method that lacks sensitivity, portability and speed. We have previously shown that specific metabolomic profiles can be detected in the blood of typhoid patients from Nepal (Näsström et al., 2014). Here, we performed mass spectrometry on plasma from Bangladeshi and Senegalese patients with culture confirmed typhoid fever, clinically suspected typhoid, and other febrile diseases including malaria. After applying supervised pattern recognition modelling, we could significantly distinguish metabolite profiles in plasma from the culture confirmed typhoid patients. After comparing the direction of change and degree of multivariate significance, we identified 24 metabolites that were consistently up- or down regulated in a further Bangladeshi/Senegalese validation cohort, and the Nepali cohort from our previous work. We have identified and validated a metabolite panel that can distinguish typhoid from other febrile diseases, providing a new approach for typhoid diagnostics.DOI:http://dx.doi.org/10.7554/eLife.15651.001

Navy beans contain bioactive phytochemicals with colon cancer prevention properties as demonstrated in carcinogen-induced animal models. Human studies support that dietary navy bean intake modulates metabolism by the gut microbiome. This study investigated the effect of navy bean ingestion on plasma and urine metabolite profiles of overweight and obese colorectal cancer survivors. Twenty participants completed a single-blinded, randomized-controlled dietary intervention with precooked navy beans (35 g bean powder/day) or control (0 g/day) for 4 weeks. Plasma and urine were collected at baseline, 2 weeks, and 4 weeks following consumption. Nontargeted metabolomics was applied to study meals and snacks, navy beans, plasma, and urine. Increased navy bean consumption was hypothesized to (i) delineate dietary biomarkers and (ii) promote metabolic shifts relevant for cancer protection in the plasma and urine metabolome. At 4 weeks, 16 plasma and 16 urine metabolites were significantly different in the navy bean intervention group compared with placebo control (P < 0.05). Increased plasma 2,3-dihydroxy-2-methylbutyrate (1.34-fold), S-methylcysteine (1.92-fold), and pipecolate (3.89-fold), and urine S-adenosylhomocysteine (2.09-fold) and cysteine (1.60-fold) represent metabolites with cancer-protective actions following navy bean consumption. Diet-derived metabolites were detected in plasma or urine and confirmed for presence in the navy bean intervention meals and snacks. These included 3-(4-hydroxyphenyl)propionate, betaine, pipecolate, S-methylcysteine, choline, eicosapentaenoate (20:5n3), benzoate, S-adenosylhomocysteine, N-delta-acetylornithine, cysteine, 3-(4-hydroxyphenyl)lactate, gentisate, hippurate, 4-hydroxyhippurate, and salicylate. The navy bean dietary intervention for 4 weeks showed changes to pathways of metabolic importance to colorectal cancer prevention and merit continued attention for dietary modulation in future high-risk cohort investigations. PREVENTION RELEVANCE: This clinical study suggests that increased consumption of navy beans would deliver bioactive metabolites to individuals at high risk for colorectal cancer recurrence and produce metabolic shifts in plasma and urine profiles.

&lt;div&gt;Abstract&lt;p&gt;Navy beans contain bioactive phytochemicals with colon cancer prevention properties as demonstrated in carcinogen-induced animal models. Human studies support that dietary navy bean intake modulates metabolism by the gut microbiome. This study investigated the effect of navy bean ingestion on plasma and urine metabolite profiles of overweight and obese colorectal cancer survivors. Twenty participants completed a single-blinded, randomized-controlled dietary intervention with precooked navy beans (35 g bean powder/day) or control (0 g/day) for 4 weeks. Plasma and urine were collected at baseline, 2 weeks, and 4 weeks following consumption. Nontargeted metabolomics was applied to study meals and snacks, navy beans, plasma, and urine. Increased navy bean consumption was hypothesized to (i) delineate dietary biomarkers and (ii) promote metabolic shifts relevant for cancer protection in the plasma and urine metabolome. At 4 weeks, 16 plasma and 16 urine metabolites were significantly different in the navy bean intervention group compared with placebo control (&lt;i&gt;P&lt;/i&gt; &lt; 0.05). Increased plasma 2,3-dihydroxy-2-methylbutyrate (1.34-fold), S-methylcysteine (1.92-fold), and pipecolate (3.89-fold), and urine S-adenosylhomocysteine (2.09-fold) and cysteine (1.60-fold) represent metabolites with cancer-protective actions following navy bean consumption. Diet-derived metabolites were detected in plasma or urine and confirmed for presence in the navy bean intervention meals and snacks. These included 3-(4-hydroxyphenyl)propionate, betaine, pipecolate, S-methylcysteine, choline, eicosapentaenoate (20:5n3), benzoate, S-adenosylhomocysteine, N-delta-acetylornithine, cysteine, 3-(4-hydroxyphenyl)lactate, gentisate, hippurate, 4-hydroxyhippurate, and salicylate. The navy bean dietary intervention for 4 weeks showed changes to pathways of metabolic importance to colorectal cancer prevention and merit continued attention for dietary modulation in future high-risk cohort investigations.&lt;/p&gt;Prevention Relevance:&lt;p&gt;This clinical study suggests that increased consumption of navy beans would deliver bioactive metabolites to individuals at high risk for colorectal cancer recurrence and produce metabolic shifts in plasma and urine profiles.&lt;/p&gt;&lt;/div&gt;

&lt;div&gt;Abstract&lt;p&gt;Navy beans contain bioactive phytochemicals with colon cancer prevention properties as demonstrated in carcinogen-induced animal models. Human studies support that dietary navy bean intake modulates metabolism by the gut microbiome. This study investigated the effect of navy bean ingestion on plasma and urine metabolite profiles of overweight and obese colorectal cancer survivors. Twenty participants completed a single-blinded, randomized-controlled dietary intervention with precooked navy beans (35 g bean powder/day) or control (0 g/day) for 4 weeks. Plasma and urine were collected at baseline, 2 weeks, and 4 weeks following consumption. Nontargeted metabolomics was applied to study meals and snacks, navy beans, plasma, and urine. Increased navy bean consumption was hypothesized to (i) delineate dietary biomarkers and (ii) promote metabolic shifts relevant for cancer protection in the plasma and urine metabolome. At 4 weeks, 16 plasma and 16 urine metabolites were significantly different in the navy bean intervention group compared with placebo control (&lt;i&gt;P&lt;/i&gt; &lt; 0.05). Increased plasma 2,3-dihydroxy-2-methylbutyrate (1.34-fold), S-methylcysteine (1.92-fold), and pipecolate (3.89-fold), and urine S-adenosylhomocysteine (2.09-fold) and cysteine (1.60-fold) represent metabolites with cancer-protective actions following navy bean consumption. Diet-derived metabolites were detected in plasma or urine and confirmed for presence in the navy bean intervention meals and snacks. These included 3-(4-hydroxyphenyl)propionate, betaine, pipecolate, S-methylcysteine, choline, eicosapentaenoate (20:5n3), benzoate, S-adenosylhomocysteine, N-delta-acetylornithine, cysteine, 3-(4-hydroxyphenyl)lactate, gentisate, hippurate, 4-hydroxyhippurate, and salicylate. The navy bean dietary intervention for 4 weeks showed changes to pathways of metabolic importance to colorectal cancer prevention and merit continued attention for dietary modulation in future high-risk cohort investigations.&lt;/p&gt;Prevention Relevance:&lt;p&gt;This clinical study suggests that increased consumption of navy beans would deliver bioactive metabolites to individuals at high risk for colorectal cancer recurrence and produce metabolic shifts in plasma and urine profiles.&lt;/p&gt;&lt;/div&gt;

BackgroundGestational diabetes mellitus (GDM) is defined as impaired glucose tolerance in pregnancy and without a history of diabetes mellitus. While there are limited metabolomic studies involving advanced maternal age in China, we aim to investigate the metabolomic profiling of plasma and urine in pregnancies complicated with GDM aged at 35–40 years at early and late gestation.MethodsTwenty normal and 20 GDM pregnant participants (≥ 35 years old) were enlisted from the Complex Lipids in Mothers and Babies (CLIMB) study. Maternal plasma and urine collected at the first and third trimester were detected using gas chromatography-mass spectrometry (GC-MS).ResultsOne hundred sixty-five metabolites and 192 metabolites were found in plasma and urine respectively. Urine metabolomic profiles were incapable to distinguish GDM from controls, in comparison, there were 14 and 39 significantly different plasma metabolites between the two groups in first and third trimester respectively. Especially, by integrating seven metabolites including cysteine, malonic acid, alanine, 11,14-eicosadienoic acid, stearic acid, arachidic acid, and 2-methyloctadecanoic acid using multivariant receiver operating characteristic models, we were capable of discriminating GDM from normal pregnancies with an area under curve of 0.928 at first trimester.ConclusionThis study explores metabolomic profiles between GDM and normal pregnancies at the age of 35–40 years longitudinally. Several compounds have the potential to be biomarkers to predict GDM with advanced maternal age. Moreover, the discordant metabolome profiles between the two groups could be useful to understand the etiology of GDM with advanced maternal age.

Metabolomics approaches in humans have identified around 40 plasma metabolites associated with insulin resistance (IR) and type 2 diabetes, which often coincide with those for obesity. We aimed to separate diabetes-associated from obesity-associated metabolite alterations in plasma and study the impact of metabolically important tissues on plasma metabolite concentrations. Two obese mouse models were studied; one exclusively with obesity (ob/ob) and another with type 2 diabetes (db/db). Both models have impaired leptin signalling as a cause for obesity, but the different genetic backgrounds determine the susceptibility to diabetes. In these mice, we profiled plasma, liver, skeletal muscle and adipose tissue via semi-quantitative GC-MS and quantitative liquid chromatography (LC)-MS/MS for a wide range of metabolites. Metabolite profiling identified 24 metabolites specifically associated with diabetes but not with obesity. Among these are known markers such as 1,5-anhydro-D-sorbitol, 3-hydroxybutyrate and the recently reported marker glyoxylate. New metabolites in the diabetic model were lysine, O-phosphotyrosine and branched-chain fatty acids. We also identified 33 metabolites that were similarly altered in both models, represented by branched-chain amino acids (BCAA) as well as glycine, serine, trans-4-hydroxyproline, and various lipid species and derivatives. Correlation analyses showed stronger associations for plasma amino acids with adipose tissue metabolites in db/db mice compared with ob/ob mice, suggesting a prominent contribution of adipose tissue to changes in plasma in a diabetic state. By studying mice with metabolite signatures that resemble obesity and diabetes in humans, we have found new metabolite entities for validation in appropriate human cohorts and revealed their possible tissue of origin.