Nicotinuric acid: a potential marker of metabolic syndrome through a metabolomics-based approach

Revealing the 1H-NMR Profiling of Six Edible Mushrooms Consumed in the Northeastern Highlands of Puebla, Mexico

The 1H-NMR metabolomics profiling of six edible mushrooms consumed in the northeastern highlands of Puebla, Mexico is presented. These fungi were morpho- and molecularly identified as Infundibulicybe squamulosa, Amanita jacksonii, Lepista nuda, Russula delica, Russula brevipes, and Lactarius indigo. The chemical profiling confirmed the presence of eight essential amino acids and their derivatives, six organic acids, six nucleosides, low amounts of reducing sugars, and valuable nutraceuticals such as betaine, carnitine, glycero-3-phosphocholine and O-acetylcarnitine which were differentially determined and quantified in the six mushrooms by qNMR. Principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA) generated four different groups. Two of these groups were constituted by fungal species with phylogenic relationships whereas non-phylogenetic related species were separated from each other. The potential use of 1H-NMR metabolomics and chemometrics to group macromycetes and determine the nutritional and nutraceutical potential of these local foods is demonstrated.

Characterizing the dynamics of the rumen microbiota, its metabolites, and blood metabolites across reproductive stages in Small-tailed Han sheep

IMPORTANCE

Our study illustrates the succession of the rumen microbiota and its metabolites in Small-tailed Han sheep at different reproductive stages. Among them, Firmicutes and Prevotella, which are related to energy metabolism, increased in abundance during pregnancy, while Fibrobacter, a fiber-degrading bacterium, increased in abundance during lactation. At the same time, the microbial metabolic profile and serum metabolic profile characteristics of different reproductive stages were revealed, and some functional pathways and metabolites related to energy and immunity were found. This study provides a reference for the health management of ruminants during non-pregnancy, pregnancy, and lactation.

Antihypertensive activity of different components of Veratrum alkaloids through metabonomic data analysis

BACKGROUND

Hypertension is a serious global public health issue. Blood pressure (BP) is still not effectively controlled in about 20 - 30% of hypertensive patients. Therefore, it is imperative to develop new treatments for hypertension. Veratrum alkaloids were once used for the clinical treatment of hypertension, the mechanism of which is still unclear. It was gradually phased out due to adverse reactions.

PURPOSE

This study aimed to investigate the short-term and long-term hypotensive profiles of different components of Veratrum alkaloids in spontaneously hypertensive rats (SHRs) to unveil their mechanisms of action.

RESULTS

Total Veratrum alkaloid (V), component A (A), and veratramine (M) quickly decreased BP within 30 min of treatment, reduced renal and cardiovascular damage, and improved relevant biochemical indicators (nitric oxide [NO], endothelin-1 [ET-1], angiotensin II [Ang II)], noradrenaline [NE], etc) in SHRs to delay stroke occurrence. Thereinto, A exhibited excellent protective effects in cardiovascular disease. The metabolomic profiles of SHRs treated with V, A, and M were significantly different from those of SHRs treated with vehicle. Thirteen metabolites were identified as potential pharmacodynamic biomarkers. Through Kyoto Encyclopedia of Genes and Genomes analysis, V, A, and M-induced hypotension was mainly related to alterations in nicotinate and nicotinamide metabolism, GABAergic synapses, linoleic acid metabolism, ketone body synthesis and degradation, arginine and proline metabolism, and urea cycle, of which nicotinate and nicotinamide metabolism was the key metabolic pathway to relieve hypertension.

CONCLUSION

This work shows that A is an effective and promising antihypertensive agent for hypertension treatment to reduce BP and hypertensive target organ damage, which is mainly mediated through modulating nicotinate and nicotinamide metabolism, RAS, and NO-ET homeostasis.

Urine and serum metabolomics study of wild ginseng in rats with spleen-qi deficiency using rapid resolution liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry

Patients with a spleen-qi deficiency often exhibit dysfunction in the metabolic system. Metabolites are considered the most direct reflection of individual physiological and pathological conditions and represent attractive candidates to provide deep insights into disease phenotypes. This study examines the potential therapeutic mechanism of wild ginseng on spleen-qi deficiency through the analysis of serum and urine metabolomics using rapid-resolution liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry. The reasons for the superiority of wild ginseng treatment over cultivated ginseng were also analyzed in depth. After wild ginseng intervention, anandamide, urobilinogen, aldosterone, and testosterone glucuronide were significantly reduced in serum. Meanwhile, argininosuccinic acid, L-cysteine, and seven other metabolites were significantly elevated in serum. Nine metabolites, including L-acetylcarnitine, and citrulline were elevated in the urine, and trimethylamine N-oxide, adrenic acid, and 10 other metabolites were reduced. Arginine biosynthesis, pantothenate and CoA biosynthesis, thiamin metabolism, taurine, and tryptophan metabolism pathways were mainly improved. Further analysis was conducted on the relationship between Lactobacillus and Akkermansia bacteria with metabolites, and it was found that they are mainly related to amino acid metabolites. This study provides strong theoretical support and direction for further explanation of the immune mechanism of wild ginseng and lays the foundation for future studies.

Comprehensive transcriptomics and metabolomics analyses reveal that hyperhomocysteinemia is a high risk factor for coronary artery disease in a chinese obese population aged 40-65: a prospective cross-sectional study

BACKGROUND

Clinical observations suggest a complex relationship between obesity and coronary artery disease (CAD). This study aimed to characterize the intermediate metabolism phenotypes among obese patients with CAD and without CAD.

METHODS

Sixty-two participants who consecutively underwent coronary angiography were enrolled in the discovery cohort. Transcriptional and untargeted metabolomics analyses were carried out to screen for key molecular changes between obese patients with CAD (CAD obese), without CAD (Non-CAD obese), and Non-CAD leans. A targeted GC-MS metabolomics approach was used to further identify differentially expressed metabolites in the validation cohorts. Regression and receiver operator curve analysis were performed to validate the risk model.

RESULTS

We found common aberrantly expressed pathways both at the transcriptional and metabolomics levels. These pathways included cysteine and methionine metabolism and arginine and proline metabolism. Untargeted metabolomics revealed that S-adenosylhomocysteine (SAH), 3-hydroxybenzoic acid, 2-hydroxyhippuric acid, nicotinuric acid, and 2-arachidonoyl glycerol were significantly elevated in the CAD obese group compared to the other two groups. In the validation study, targeted cysteine and methionine metabolomics analyses showed that homocysteine (Hcy), SAH, and choline were significantly increased in the CAD obese group compared with the Non-CAD obese group, while betaine, 5-methylpropanedioic acid, S-adenosylmethionine, 4-PA, and vitamin B2 (VB2) showed no significant differences. Multivariate analyses showed that Hcy was an independent predictor of obesity with CAD (hazard ratio 1.7; 95%CI 1.2-2.6). The area under the curve based on the Hcy metabolomic (HCY-Mtb) index was 0.819, and up to 0.877 for the HCY-Mtb.index plus clinical variables.

CONCLUSION

This is the first study to propose that obesity with hyperhomocysteinemia is a useful intermediate metabolism phenotype that could be used to identify obese patients at high risk for developing CAD.

Defining NAD(P)(H) Catabolism

Dietary vitamin B3 components, such as nicotinamide and nicotinic acid, are precursors to the ubiquitous redox cofactor nicotinamide adenine dinucleotide (NAD⁺). NAD⁺ levels are thought to decline with age and disease. While the drivers of this decline remain under intense investigation, strategies have emerged seeking to functionally maintain NAD⁺ levels through supplementation with NAD⁺ biosynthetic intermediates. These include marketed products, such as nicotinamide riboside (NR) and its phosphorylated form (NMN). More recent developments have shown that NRH (the reduced form of NR) and its phosphorylated form NMNH also increases NAD⁺ levels upon administration, although they initially generate NADH (the reduced form of NAD⁺). Other means to increase the combined levels of NAD⁺ and NADH, NAD(H), include the inhibition of NAD⁺-consuming enzymes or activation of biosynthetic pathways. Multiple studies have shown that supplementation with an NAD(H) precursor changes the profile of NAD(H) catabolism. Yet, the pharmacological significance of NAD(H) catabolites is rarely considered although the distribution and abundance of these catabolites differ depending on the NAD(H) precursor used, the species in which the study is conducted, and the tissues used for the quantification. Significantly, some of these metabolites have emerged as biomarkers in physiological disorders and might not be innocuous. Herein, we review the known and emerging catabolites of the NAD(H) metabolome and highlight their biochemical and physiological function as well as key chemical and biochemical reactions leading to their formation. Furthermore, we emphasize the need for analytical methods that inform on the full NAD(H) metabolome since the relative abundance of NAD(H) catabolites informs how NAD(H) precursors are used, recycled, and eliminated.

Serum metabolomics profiling of improved metabolic syndrome is characterized by decreased pro-inflammatory biomarkers: A longitudinal study in Chinese male adults

Metabolic syndrome (MetS) is a serious global health concern. The objective of this study is to dynamically investigate the changes of metabolic profiles and metabolites in Chinese male MetS subjects after an 18 months diet and exercise intervention. Fifty male MetS patients defined according to International Diabetes Federation 2005 guidelines were subjected to diet and exercise counseling for 18 months. Serum samples were taken at baseline, 12 months, and 18 months, respectively, for clinical evaluation and metabolomics analyses. Diet and exercise intervention for 18 months achieved significant improvements in the metabolic profiles of all participants. Nineteen subjects (38.0%) exhibited MetS remission at the end of the study. A total of 812 relative features were characterized and 61 were successfully identified. Furthermore, 17 differential metabolites were of significance at both time points (baseline-12 months, baseline-18 months) and presented nonlinear trends through time. Eight metabolites (47.1%) were predominantly converged to inflammation and oxidative stress. Pro-inflammatory biomarkers were remarkably decreased after 18 months of intervention, and prostaglandin E2, neuroprotectin D1, and taxiphyllin in combination were firstly found to demonstrate a fair discriminative power (area under curve = 0.911) to predict the improvement of MetS undergone diet and exercise intervention. The significant shift of metabolomic profiling after 18 months of lifestyle counseling provide a novel insight and reveal that earlier inflammation control may be of potential benefit in MetS management.

L, E. E, Qi R, Mu X, Feng L, Ba G, Li Y, Zhang J, Bai L, Fu M. Metabolomics analysis reveals amelioration effects of yellowhorn tea extract on hyperlipidemia, inflammation, and oxidative stress in high-fat diet-fed mice

Yellowhorn tea (YT) is traditionally used as a lipid-lowering beverage in Mongolian minorities. However, the pharmacological effects of YT extract and its specific metabolic changes in hyperlipidemia models are not fully understood. The aim of this study was to identify biomarkers using untargeted metabolomics techniques and to investigate the mechanisms underlying the changes in metabolic pathways associated with lipid lowering, anti-inflammation and anti-oxidant in hyperlipidemic mice. A high-fat diet (HFD)-induced hyperlipidemic mouse model was established. YT extract was administered as oral gavage at 0.15, 0.3, and 0.6 g/kg doses for 10 weeks. HFD-induced hyperlipidemia and the therapeutic effect of YT extract were evaluated based on histopathology and by assessing blood lipid levels. Liver inflammatory factors and oxidative stress indices were determined using enzyme-linked immunosorbent assays. Liver metabolites were evaluated using untargeted metabolomics. Biochemical and histological examinations showed that YT extract significantly reduced body-weight gain (p < 0.01) and fat deposition in tissues. YT extract significantly reduced the levels of serum and liver triglyceride and total cholesterol; inflammatory factors [interleukin (IL)-6, IL-1β, and tumor necrosis factor-α]; malondialdehyde; and leptin (p < 0.05) in hyperlipidemic mice. YT extract also significantly increased the levels of oxidative stress indicators (superoxide dismutase, catalase, and glutathione peroxidase) and adiponectin. Metabolomics studies revealed several endogenous molecules were altered by the high-fat diet and recovery following intervention with YT extract. The metabolites that were significantly different in the liver after YT intake included citicoline, acetylcholine, pyridoxine, and NAD. Pathway analysis indicated that YT extract ameliorated HFD-induced hyperlipidemia in mice via three major metabolic pathways, namely, glycerophospholipid metabolism, vitamin B6 metabolism, and nicotinate and nicotinamide metabolism. This study demonstrates YT extract has profound effects on the alleviation of HFD-induced hyperlipidemia, inflammation and oxidative stress.

Inulin and Chinese Gallotannin Affect Meat Quality and Lipid Metabolism on Hu Sheep

The aim of this study was to investigate the impacts of inulin and Chinese gallotannin on the meat fatty acids and urinary metabolites in sheep. Twenty-four healthy (25.80 ± 3.85 kg) weaned Hu lambs of approximately 4.5 months old were equally divided into four groups: control group (basal diet), treatment group I (basal diet + 0.1% inulin), treatment group II (basal diet + 0.1% inulin + 2% Chinese gallotannin), and treatment group III (basal diet + 0.1% inulin + 2% Chinese gallotannin + 4% PEG). The contents of myristic acid (C14:0) and palmitic acid (C16:0) were found to be lower in treatment group II than in the control group (p < 0.05). Moreover, the palmitoleic acid (C16:1) content in treatment group II was notably higher than that in the control group (p < 0.05), while the elaidic acid (C18:1n9t) content in treatment group II was higher than that in other groups (p < 0.05). Besides, the linoleic acid (C18:2n6c) content was higher in the treatment II and control groups than in the treatment I and III groups. Furthermore, compared with the control group, both 4-pyridoxic acid and creatinine in treatment groups I and II were upregulated (p < 0.05), while other metabolites, such as nicotinuric acid, l-threonine, palmitic acid, and oleic acid, were drastically downregulated (p < 0.05). These differential metabolites were found to be mainly involved in nicotinate and nicotinamide metabolism (ko00760), vitamin B6 metabolism (ko00750), and the fatty acid biosynthesis pathway (ko00061). It is concluded that the combination of inulin and Chinese gallotannin in the diet could improve the energy and lipid metabolism of sheep, which may improve both mutton quality and production performance.

Walker-256 Tumour-Induced Cachexia Altered Liver Metabolomic Profile and Function in Weanling and Adult Rats

Cancer cachexia occurs in up to 85% of advanced cancer patients, affecting different tissues and organs, mainly the liver, which plays a central role in body metabolism control. However, liver responses to cancer cachexia progression are still poorly understood. Considering the possible different challenges provided by the rodent’s phase of life and the cachexia progression, we evaluated the liver metabolic alterations affected by Walker-256 tumour growth in weanling and young-adult rats. For this, we applied a metabolomics approach associated with protein and gene expression analyses. Higher amino acid levels and impaired glucose metabolism were important features in tumour-bearing animals’ liver tissue. The weanling hosts had more pronounced cachexia, with higher carcass spoliation, liver lipid metabolism and impaired CII and CIV mitochondrial complexes. The liver alterations in young adult tumour-bearing rats were related to energy status and nucleotide metabolites, such as uridine, NAD+, xanthosine, hypoxanthine and inosine. In conclusion, the Walker-256 tumour-induced cachexia impaired liver metabolism, being more severe in the weanling hosts. Further studies are needed to correlate these changes in the preclinical model, which can be correlated to the clinical features of cancer cachexia, allowing for a translational potential involving the liver function and its responses to potential treatments.

Urinary metabolomics analysis of the protective effects of Daming capsule on hyperlipidemia rats using ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry

Hyperlipidemia is recognized as one of the most important risk factors for morbidity and mortality due to cardiovascular diseases. Daming capsule, a Chinese patent medicine, has shown definitive efficacy in patients with hyperlipidemia. In this study, serum biochemistry and histopathology assessment were used to investigate the lipid-lowering effect of Daming capsule. Furthermore, urinary metabolomics based on ultra high performance liquid chromatography with quadrupole time-of-flight mass spectrometry was conducted to identify the urinary biomarkers associated with hyperlipidemia and discover the underlying mechanisms of the antihyperlipidemic action of Daming capsule. After 10 weeks of treatment, Daming capsule significantly lowered serum lipid levels and ameliorated hepatic steatosis induced by a high-fat diet. A total of 33 potential biomarkers associated with hyperlipidemia were identified, among which 26 were robustly restored to normal levels after administration of Daming capsule. Pathway analysis revealed that the lipid-lowering effect of Daming capsule is related to the regulation of multiple metabolic pathways including vitamin B and amino acid metabolism, tricarboxylic acid cycle, and pentose phosphate pathway. Notably, the study demonstrates that metabolomics is a powerful tool to elucidate the multitarget mechanism of traditional Chinese medicines, thereby promoting their research and development.

A metabolomics approach to investigate the proceedings of mitochondrial dysfunction in rats from prediabetes to diabetes

Diabetes mellitus (DM) is a leading cause of preventable cardiovascular disease, but the metabolic changes from prediabetes to diabetes have not been fully clarified. This study implemented a metabolomics profiling platform to investigate the variations of metabolites and to elucidate their global profiling from metabolic syndrome to DM. Methods: Male Sprague-Dawley rats (n = 44) were divided into four groups. Three groups were separately fed with a normal diet, a high-fructose diet (HF), or a high-fat (HL) diet while one group was treated with streptozotocin. The HF and HL diet were meant to induce insulin resistance, obesity, and dyslipidemia, which known to induce DM. Results: The most significant metabolic variations in the DM group’s urine samples were the reduced release of citric acid cycle intermediates, the increase in acylcarnitines, and the decrease in urea excretion, all of which indicated energy metabolism abnormalities and mitochondrial dysfunction. Overall, the metabolic analysis revealed tryptophan metabolic pathway variations in the prediabetic phase, even though the mitochondrial function remains unaffected. Conclusion: This study show that widespread methylations and impaired tryptophan metabolism occur in metabolic syndrome and are then followed by a decline in citric acid cycle intermediates, indicating mitochondrial dysfunction in diabetes.

Effect of Dapagliflozin on Urine Metabolome in Patients with Type 2 Diabetes

CONTEXT

Inhibitors of sodium-glucose cotransporters-2 have cardio- and renoprotective properties. However, the underlying mechanisms remain indeterminate.

OBJECTIVE

To evaluate the effect of dapagliflozin on renal metabolism assessed by urine metabolome analysis in patients with type 2 diabetes.

DESIGN

Prospective cohort study.

SETTING

Outpatient diabetes clinic of a tertiary academic center.

PATIENTS

Eighty patients with hemoglobin A1c > 7% on metformin monotherapy were prospectively enrolled.

INTERVENTION

Fifty patients were treated with dapagliflozin for 3 months. To exclude that the changes observed in urine metabolome were merely the result of the improvement in glycemia, 30 patients treated with insulin degludec were used for comparison.

MAIN OUTCOME MEASURE

Changes in urine metabolic profile before and after the administration of dapagliflozin and insulin degludec were assessed by proton-nuclear magnetic resonance spectroscopy.

RESULTS

In multivariate analysis urine metabolome was significantly altered by dapagliflozin (R2X = 0.819, R2Y = 0.627, Q2Y = 0.362, and coefficient of variation analysis of variance, P < 0.001) but not insulin. After dapagliflozin, the urine concentrations of ketone bodies, lactate, branched chain amino acids (P < 0.001), betaine, myo-inositol (P < 0001), and N-methylhydantoin (P < 0.005) were significantly increased. Additionally, the urine levels of alanine, creatine, sarcosine, and citrate were also increased (P < 0001, P <0.0001, and P <0.0005, respectively) whereas anserine decreased (P < 0005).

CONCLUSIONS

Dapagliflozin significantly affects urine metabolome in patients with type 2 diabetes in a glucose lowering-independent way. Most of the observed changes can be considered beneficial and may contribute to the renoprotective properties of dapagliflozin.

Metabolomics-based multidimensional network biomarkers for diabetic retinopathy identification in patients with type 2 diabetes mellitus

INTRODUCTION

Despite advances in diabetic retinopathy (DR) medications, early identification is vitally important for DR administration and remains a major challenge. This study aims to develop a novel system of multidimensional network biomarkers (MDNBs) based on a widely targeted metabolomics approach to detect DR among patients with type 2 diabetes mellitus (T2DM) efficiently.

RESEARCH DESIGN AND METHODS

In this propensity score matching-based case-control study, we used ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry system for serum metabolites assessment of 69 pairs of patients with T2DM with DR (cases) and without DR (controls). Comprehensive analysis, including principal component analysis, orthogonal partial least squares discriminant analysis, generalized linear regression models and a 1000-times permutation test on metabolomics characteristics were conducted to detect candidate MDNBs depending on the discovery set. Receiver operating characteristic analysis was applied for the validation of capability and feasibility of MDNBs based on a separate validation set.

RESULTS

We detected 613 features (318 in positive and 295 in negative ESI modes) in which 63 metabolites were highly relevant to the presence of DR. A panel of MDNBs containing linoleic acid, nicotinuric acid, ornithine and phenylacetylglutamine was determined based on the discovery set. Depending on the separate validation set, the area under the curve (95% CI), sensitivity and specificity of this MDNBs system were 0.92 (0.84 to 1.0), 96% and 78%, respectively.

CONCLUSIONS

This study demonstrates that metabolomics-based MDNBs are associated with the presence of DR and capable of distinguishing DR from T2DM efficiently. Our data also provide new insights into the mechanisms of DR and the potential value for new treatment targets development. Additional studies are needed to confirm our findings.

Liquid chromatography-mass spectrometry untargeted metabolomics reveals increased levels of tryptophan indole metabolites in urine of metabolic syndrome patients

Metabolic syndrome (MetS) is a multifactor condition predisposing for diabetes, cardiovascular diseases and other degenerative disorders. Although several diagnostic criteria have been established, none of them is specific and there is a call for better pathophysiological explanation of MetS and for the discovery of molecular biomarkers. Phenotype characterization at metabolome level might be useful for both purposes. To this end, our aim was to perform comparative untargeted metabolomics of urines from MetS patients and from the control group. The study participants included 52 diagnosticated and 50 healthy individuals from Leon city in central Mexico; 23 anthropometric and clinical parameters were measured and submitted to Principal Component Analysis (PCA). The obtained PCA model allowed us for selection of 11 MetS patients and 13 control subjects, correspondingly representative for each of the two groups (clearly separated in PCA). The first morning urines from these subjects were ambulatory collected and, after methanol extraction and acidification, were submitted to capillary liquid chromatography-high resolution mass spectrometry (LC-HRMS). The obtained data were analyzed on MetaboScape® platform (Bruker Daltonics). Specifically, t-test applied to LC-HRMS data revealed several ions presenting at least 3-fold higher intensities in MetS with respect to the control samples (p < 0.05). Data analysis and complementary experiments yielded the identification of the following metabolites: indole-3-acetic acid, indole-3-acetic acid-O-glucuronide, N-(indol-3-ylacetyl) glutamine, indole-3-carbaldehyde and hydroxyhexanoycarnitine. Additionally, indole-3-carboxylic acid was annotated with 2.13-fold higher abundance in MetS patients. To assess the contribution of individual metabolites in the difference between two groups of subjects, partial least square discriminant analysis was performed for LC-HRMS data and the obtained values of variable importance in projection (VIP), confirmed the association of six above mentioned compounds with MetS. Overall, this study provides direct evidence on the disturbed catabolism of tryptophan in metabolic syndrome.

Plasma metabolomics are associated with metabolic syndrome: A targeted approach

OBJECTIVES

Advances in metabolomic tools have allowed us to gain a more comprehensive understanding of metabolic syndrome (MetS). The aim of this study was to evaluate the association between plasma metabolomic profiles and MetS.

METHODS

For this study, adults without diabetes, chronic kidney disease, stroke, heart disease, or cancer and with full metabolomics, biochemical, and dietetic data available, representing a subsample of the Health Survey of Sao Paulo study (ISA-Capital; N = 130), were included. The joint interim statement consensus criteria were used for diagnosing MetS. Absolute quantification (µmol/L) of blood metabolites was achieved by targeted quantitative profiling of annotated metabolites by electrospray ionization tandem mass spectrometry in plasma samples. Mean differences in the compounds for MetS were evaluated by linear regression adjusted for confounding factors.

RESULTS

Serine was inversely associated with MetS (β = -15.04; P = 0.014). In glycerophospholipids with acyl-alkyl bonds, there was an inverse association with MetS, including phosphatidylcholine (PC) ae C42:5 (β = -0.15; P = 0.040), PC ae C44:5 (β = -0.15; P = 0.046), PC ae C40:4 (β = -0.21; P = 0.014) and PC ae C44:4 (β = -0.04; P = 0.032).

CONCLUSION

Plasma metabolomic profiles were associated with MetS, especially the amino acid serine and some acyl-alkyl PCs.

Targeted Metabolomics for Plasma Amino Acids and Carnitines in Patients with Metabolic Syndrome Using HPLC-MS/MS

Metabolic syndrome (MetS) is a health disorder characterized by metabolic abnormalities that predict an increased risk to develop cardiovascular disease (CVD) and type 2 diabetes. Biomarkers can provide an insight into the novel mechanism for MetS and can be potentially used for personalized response to therapies. We exploited a targeted HPLC-MS/MS method to characterize plasma amino acids and carnitine metabolic profile in MetS patients. A training set (40 cases and 40 controls) and validation set (80 MetS patients and 80 healthy controls) were carried out to find the metabolic profiles. We discovered two carnitine metabolites including hydroxydecanoyl carnitine and methylglutarylcarnitine. Our results indicated that the decreased level of hydroxydecanoyl carnitine and methylglutarylcarnitine may be associated with the risk of MetS. These biomarkers may improve the risk prediction and provide a novel tool for monitoring of the progression of disease and response to treatment in MetS patients.

Untargeted UPLC-MS metabolomics reveals multiple changes of urine composition in healthy adult volunteers after consumption of curcuma longa L. extract

Curcuma longa L. is used as food supplement to prevent diseases, although limited studies have been performed on healthy subjects up to now. In the present work, an untargeted UPLC-MS metabolomics approach was applied to study the changes of 24-hours urinary composition on healthy volunteers due to a 28-days daily consumption of a dried C. longa extract containing a standardized amount of curcuminoids. Changes in the excretion of different metabolites were observed after supplementation. Curcumin and two metabolic derivatives (hexahydrocurcumin and dihydrocurcumin) were detected in urine, indicating the absorption of the main curcuminoid from the extract and its further metabolism by liver and gut microbiota. For the first time ar-turmerone, the main apolar constituent of curcuma, was detected in urine in intact form, and its presence was confirmed by a targeted GC-MS analysis. The increase of tetranor-PGJM and tetranor-PGDM, two prostaglandin-D2 metabolites, was observed, being related to the anti-inflammatory effect exerted by curcuma. The variation of the amounts of HPAG, PAG, proline-betaine and hydroxyphenyllactic acid indicate that the supplementation induced changes to the activity of gut microbiota. Finally, the reduced excretion of niacin metabolites (nicotinuric acid, trigonelline and 2PY) and medium- and short-chain acylcarnitines suggests that curcuma could induce the mitochondrial β-oxidation of fatty acids for energy production in healthy subjects. Overall, the results indicate that a prolonged daily consumption of a dried curcuma extract exerts multiple effects on healthy subjects, furthermore they show the opportunity offered by untargeted metabolomics for the study of the bioactivity of natural extracts in healthy human volunteers.

Discovery of metabolite profiles of metabolic syndrome using untargeted and targeted LC-MS based lipidomics approach

Metabolic syndrome (MetS) is an important risk factor for type 2 diabetes, cardiovascular diseases and all-cause morbidity and mortality. Biomarkers can provide insight into the mechanism, facilitate early detection, and monitor progression of MetS and its response to therapeutic interventions. To identify potential biomarkers, we applied a non-targeted and targeted lipidomics method to characterize plasma metabolic profile in MetS patients. Metabolic profiling was performed on a non-target set (40 cases and 40 controls) on UHPLC-Q-TOF/MS and target set (80 MetS patients and 80 healthy controls) on UHPLC-Q-orbitrap MS. Using comprehensive screening and validation workflow, we identified a panel of three metabolites including PC(18:1/P-16:0), PC(o-22:3/22:3), PC(P-18:1/16:1). Our results indicated that the identified biomarkers may improve the risk prediction and provide a novel tool for monitoring of the progression of disease and response to treatment in MetS patients.

Comparison of the Serum Metabolic Fingerprint of Different Exercise Modes in Men with and without Metabolic Syndrome

Exercise plays a beneficial role in the treatment of metabolic syndrome (MetS). Metabolomics can provide new insights and facilitate the optimization of exercise prescription. This study aimed to investigate whether the response of the human serum metabolic fingerprint to exercise depends on exercise mode or the presence of MetS. Twenty-three sedentary men (nine with MetS and fourteen healthy) completed four trials: Resting, high-intensity interval exercise (HIIE), continuous moderate-intensity exercise (CME), and resistance exercise (RE). Blood samples were collected pre-exercise, immediately after exercise, and 1 h post-exercise for targeted metabolomic analysis in serum by liquid chromatography–mass spectrometry. Time exerted the strongest differentiating effect, followed by exercise mode. The largest changes from baseline were found in the immediate post-exercise samples. RE caused the strongest responses overall, followed by HIIE, while CME had minimal effect. Unlike previous results in urine, no valid model could separate the two groups in serum. Exercise exerted a beneficial effect on prominent serum biomarkers of metabolic risks, such as branched-chain amino acids, alanine, acetylcarnitine, choline, and betaine. These findings contribute to the ongoing research efforts to map the molecular responses to exercise and to optimize exercise guidelines for individuals at cardiometabolic risk.

Current Progress of Lipid Analysis in Metabolic Diseases by Mass Spectrometry Methods

BACKGROUND

Obesity, insulin resistance, diabetes, and metabolic syndrome are associated with lipid alterations, and they affect the risk of long-term cardiovascular disease. A reliable analytical instrument to detect changes in the composition or structures of lipids and the tools allowing to connect changes in a specific group of lipids with a specific disease and its progress, is constantly lacking. Lipidomics is a new field of medicine based on the research and identification of lipids and lipid metabolites present in human organism. The primary aim of lipidomics is to search for new biomarkers of different diseases, mainly civilization diseases.

OBJECTIVE

We aimed to review studies reporting the application of mass spectrometry for lipid analysis in metabolic diseases.

METHOD

Following an extensive search of peer-reviewed articles on the mass spectrometry analysis of lipids the literature has been discussed in this review article.

RESULTS

The lipid group contains around 1.7 million species; they are totally different, in terms of the length of aliphatic chain, amount of rings, additional functional groups. Some of them are so complex that their complex analyses are a challenge for analysts. Their qualitative and quantitative analysis of is based mainly on mass spectrometry.

CONCLUSION

Mass spectrometry techniques are excellent tools for lipid profiling in complex biological samples and the combination with multivariate statistical analysis enables the identification of potential diagnostic biomarkers.

Metabolic Signature Differentiated Diabetes Mellitus from Lipid Disorder in Elderly Taiwanese

Aging is a complex progression of biological processes and is the causal contributor to the development of diabetes mellitus (DM). DM is the most common degenerative disease and is the fifth leading cause of death in Taiwan, where the trend of DM mortality has been steadily increasing. Metabolomics, important branch of systems biology, has been mainly utilized to understand endogenous metabolites in biological systems and their dynamic changes as they relate to endogenous and exogenous factors. The purpose of this study was to elucidate the metabolomic profiles in elderly people and its relation to lipid disorder (LD). We collected 486 elderly individuals aged ≥65 years and performed untargeted and targeted metabolite analysis using nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography—mass spectrometry (LC/MS). Several metabolites, including branched-chain amino acids, alanine, glutamate and alpha-aminoadipic acid were elevated in LD compared to the control group. Based on multivariate analysis, four metabolites were selected in the best model to predict DM progression: phosphatidylcholine acyl-alkyl (PC ae) C34:3, PC ae C44:3, SM C24:1 and PCae C36:3. The combined area under the curve (AUC) of those metabolites (0.82) was better for DM classification than individual values. This study found that targeted metabolic signatures not only distinguish the LD within the control group but also differentiated DM from LD in elderly Taiwanese. These metabolites could indicate the nutritional status and act as potential metabolic biomarkers for the elderly in Taiwan.

Perinatal exposure to low-dose decabromodiphenyl ethane increased the risk of obesity in male mice offspring

Decabromodiphenyl Ethane (DBDPE), a kind of new brominated flame retardants (NBFRs) used to replace DecaBDE, has been frequently detected in the environment and human samples. In this study, we explored its toxic effects on male mouse offspring after perinatal exposure to DBDPE. During the perinatal period, pregnant ICR mice were exposed to DBDPE (100 μg/kg body weight) via oral gavage. After weaning, male offspring were fed on a low-fat diet and a high-fat diet, respectively. We measured and recorded body weight, liver weight, and epididymis fat mass, blood biochemical markers, metabolites changes in liver, and gene expression involved in lipid and glucose homeostasis. The results showed that perinatal exposure to DBDPE increased the risk of obesity in mouse offspring and affected triglyceride synthesis, bile secretion, purine synthesis, mitochondrial function and glucose metabolism, furthermore, the use of HFD feeding may further exacerbate these effects. All of these results show that early-life exposure to low doses of DBDPE can promote the development of metabolic dysfunction, which in turn induces obesity.

Dietary supplemental Kluyveromyces marxianus alters the serum metabolite profile in broiler chickens

Metabolomics is used to evaluate the bioavailability of food components, as well as to validate the metabolic changes associated with food consumption. This study was conducted to investigate the effects of the dietary supplement Kluyveromyces marxianus on the serum metabolite profile in broiler chickens. A total of 240 1-d-old broilers were divided into 2 groups with 8 replicates. Birds were fed basal diets without or with K. marxianus supplementation (5 × 1010 CFU kg-1 of diet). Serum samples were collected on d 21 and were analyzed by high-performance liquid chromatography with quadrupole time-of flight/mass spectrometry. The results showed that supplemental K. marxianus altered the concentrations of a variety of metabolites in the serum. Thereinto, a total of 39 metabolites were identified at higher (P < 0.05) concentrations while 21 metabolites were identified at lower (P < 0.05) concentrations in the treatment group as compared with the control. These metabolites were primarily involved with the regulation of amino acids and carbohydrate metabolism. Further metabolic pathway analysis revealed that glutamine and glutamate metabolism was the most relevant and critical pathway identified from these two groups. The activated pathway may partially interpret the beneficial effects of K. marxianus. Overall, the present research could promote our understanding of the probiotic action of K. marxianus and provide new insight into the design and application of K. marxianus-containing functional foods.

Exposure marker discovery of di(isononyl)cyclohexane-1,2-dicarboxylate using two mass spectrometry-based metabolite profiling data processing methods

Di(isononyl)cyclohexane-1,2-dicarboxylate (DINCH) is a plasticizer used in polyvinyl chloride (PVC) products, such as toys and food packaging. Because the use of DINCH is on the rise, the risk of human exposure to this chemical may likewise increase. Discovering markers for assessing human chemical exposure is difficult because the metabolism of chemicals within humans is complex. In this study, two mass spectrometry (MS)-based metabolite profiling data processing methods, the mass defect filter (MDF) method and the signal mining algorithm with isotope tracing (SMAIT) method, were used for DINCH metabolite discovery, and 110 and 18 potential DINCH metabolite signal candidates were discovered, respectively, from in vitro DINCH incubation samples. Of these, the 21 signals were validated as tentative exposure marker signals in a rat model. Interestingly, the two methods generated rather different sets of DINCH exposure markers. Five of the 21 tentative exposure marker signals were verified as the probable DINCH structure-related metabolite signals based on their MS/MS product ion profiles. These five signals were detected in at least one human urine sample. Of the five probable DINCH structure-related metabolite signals, two novel signals might be suitable exposure markers that should be further investigated for their application in human DINCH exposure assessments. These observations indicate that the MDF and SMAIT methods may be used to discover a relatively different set of potential DINCH exposure markers.

Metabolomics insights into the modulatory effects of long-term compound polysaccharide intake in high-fat diet-induced obese rats

Background

Polysaccharides can alleviate obesity in mammals; however, studies on mechanism of this alleviation are limited. A few studies have indicated that polysaccharides improve obesity by regulating the metabolism of the body. Therefore, a metabolomics approach, consisting of high resolution nuclear magnetic resonance (NMR) spectroscopy and a multivariate statistical technique, was applied to explore the mechanism of the protective effects of lentinan and Flos Lonicera polysaccharides (LF) on high-fat diet (HFD) induced obesity.

Methods

In this study, rats were randomly divided into three groups: control diet (CD), HFD, and HFD supplemented with a mixture of lentinan and Flos Lonicera polysaccharide. Histopathological and clinical biochemical assessments were also conducted. A combination of a NMR metabolomics study and a multivariable statistical analysis method to distinguish urinary and fecal metabolites was applied.

Results

Significant obesity symptoms appeared in HFD rats (for example, significant weight gain, epididymal adipose accumulation and lipid deposition in hepatocytes), which was attenuated in the LF group. Additionally, the HFD induced a reduction of choline, citrate, pyruvate and glycerol and increased the levels of trimethylamine oxide (TMAO) and taurine. Of note, these metabolic disorders were reversed by LF intervention mainly through pathways of energy metabolism, choline metabolism and gut microbiota metabolism.

Conclusions

LF supplementation had a re-balancing effect on the disturbed metabolic pathways in the obese body. The results of this study validate the therapeutic effect of the compound polysaccharide--LF in obesity and described the biochemical and metabolic mechanisms involved.

Electronic supplementary material

The online version of this article (10.1186/s12986-018-0246-2) contains supplementary material, which is available to authorized users.

Improving Metabolic Health Through Precision Dietetics in Mice

The incidence of diet-induced metabolic disease has soared over the last half-century, despite national efforts to improve health through universal dietary recommendations. Studies comparing dietary patterns of populations with health outcomes have historically provided the basis for healthy diet recommendations. However, evidence that population-level diet responses are reliable indicators of responses across individuals is lacking. This study investigated how genetic differences influence health responses to several popular diets in mice, which are similar to humans in genetic composition and the propensity to develop metabolic disease, but enable precise genetic and environmental control. We designed four human-comparable mouse diets that are representative of those eaten by historical human populations. Across four genetically distinct inbred mouse strains, we compared the American diet's impact on metabolic health to three alternative diets (Mediterranean, Japanese, and Maasai/ketogenic). Furthermore, we investigated metabolomic and epigenetic alterations associated with diet response. Health effects of the diets were highly dependent on genetic background, demonstrating that individualized diet strategies improve health outcomes in mice. If similar genetic-dependent diet responses exist in humans, then a personalized, or "precision dietetics," approach to dietary recommendations may yield better health outcomes than the traditional one-size-fits-all approach.

Docosapentaenoic acid and docosahexaenoic acid are positively associated with insulin sensitivity in rats fed high-fat and high-fructose diets

BACKGROUND

The aim of the present study was to compare insulin resistance and metabolic changes using a global lipidomic approach.

METHODS

Rats were fed a high-fat diet (HFD) or a high-fructose diet (HFrD) for 12 weeks to induce insulin resistance (IR) syndrome. After 12 weeks feeding, physiological and biochemical parameters were examined. Insulin sensitivity and plasma metabolites were evaluated using a euglycemic-hyperinsulinemic clamp and mass spectrometry, respectively. Pearson's correlation coefficient was used to investigate the strength of correlations.

RESULTS

Rats on both diets developed IR syndrome, characterized by hypertension, hyperlipidemia, hyperinsulinemia, impaired fasting glucose, and IR. Compared with HFrD-fed rats, non-esterified fatty acids were lower and body weight and plasma insulin levels were markedly higher in HFD-fed rats. Adiposity and plasma leptin levels were increased in both groups. However, the size of adipocytes was greater in HFD- than HFrD-fed rats. Notably, the lipidomic heat map revealed metabolites exhibiting greater differences in HFD- and HFrD-fed rats compared with controls. Plasma adrenic acid levels were higher in HFD- than HFrD-fed rats. Nevertheless, linoleic and arachidonic acid levels decreased in HFrD-fed rats compared with controls. Plasma concentrations of docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) were significantly reduced after feeding of both diets, particularly the HFrD. There was a strong positive correlation between these two fatty acids and the insulin sensitivity index.

CONCLUSIONS

The systemic lipidomic analysis indicated that a reduction in DHA and DPA was strongly correlated with IR in rats under long-term overnutrition. These results provide a potential therapeutic target for IR and metabolic syndrome.

Serum lysophospholipid levels are altered in dyslipidemic hamsters

Dyslipidemias are common disorders that predispose individuals to severe diseases. It is known that healthy living habits can prevent dyslipidemias if they are diagnosed properly. Therefore, biomarkers that assist in diagnosis are essential. The aim of this study was to identify biomarkers of dyslipidemia progression, which in turn disclose its etiology. These findings will pave the way for examinations of the regulatory mechanisms involved in dyslipidemias. Hamsters were fed either a normal-fat diet (NFD) or a high-fat diet. Some of the NFD-fed animals were further treated with the hyperlipidemic agent Poloxamer 407. Non-targeted metabolomics was used to investigate progressive changes in unknown serum metabolites. The hepatic expression of putative biomarker-related genes was also analyzed. The serum levels of lysophospholipids (Lyso-PLs) and their related enzymes lecithin-cholesterol acyltransferase (LCAT), secreted phospholipase A2 (sPLA2) and paraoxonase-1 were altered in dyslipidemic hamsters. Lysophosphatidylcholine levels were increased in diet-induced dyslipidemic groups, whereas lysophosphatidylethanolamine levels increased in response to the chemical treatment. The liver was significantly involved in regulating the levels of these molecules, based on the modified expression of endothelial lipase (Lipg), sPLA2 (Pla2g2a) and acyltransferases (Lcat and Lpcat3). We concluded that Lyso-PL evaluation could aid in the comprehensive diagnosis and management of lipid disorders.

Depression contributing to dyslipidemic cardiovascular risk in the metabolic syndrome

PURPOSE

Triglycerides are considered an emerging risk factor for cardiovascular mortality. Recent evidence relating depression and metabolic syndrome (MetS) implicated triglyceride levels. We thus investigated interrelations of self-reported depression severity (Zung) and MetS-related biological measures with CVD risk estimates in MetS patients.

METHODS

N = 101 patients fulfilling International Diabetes Federation criteria for MetS from a nationwide sampled treatment cohort for MetS with familial T2DM risk or manifest T2DM in a Ukrainian governmental health care system were participants. Both laboratory and non-laboratory measures were included. Recent European cardiological SCORE system CVD risk estimates were used as outcome variables.

RESULTS

Following correlation matrix, we entered all variables into principal component analysis (PCA; 76.7% explained variance), followed by hierarchical regression and structural equation modeling (SEM). The PCA suggested a one-factor solution, where the latent variable showed highest loadings of SCORE risk estimates, triglycerides, depression severity, and pulse pressure. A comprehensive SEM was adjusted with 92.7% explained variance: overall CVD risk related to depression, pulse pressure, triglycerides, and fasting glucose.

CONCLUSION

The findings in this MetS sample suggest that triglycerides and depression severity are the key variables among MetS biomarkers in cross-sectionally associating with the fatal and total SCORE risk estimates in MetS.

Effects of Different Exercise Modes on the Urinary Metabolic Fingerprint of Men with and without Metabolic Syndrome

Exercise is important in the prevention and treatment of the metabolic syndrome (MetS), a cluster of risk factors that raises morbidity. Metabolomics can facilitate the optimization of exercise prescription. This study aimed to investigate whether the response of the human urinary metabolic fingerprint to exercise depends on the presence of MetS or exercise mode. Twenty-three sedentary men (MetS, n = 9, and Healthy, n = 14) completed four trials: resting, high-intensity interval exercise (HIIE), continuous moderate-intensity exercise (CME), and resistance exercise (RE). Urine samples were collected pre-exercise and at 2, 4, and 24 h for targeted analysis by liquid chromatography-mass spectrometry. Time exerted the strongest differentiating effect, followed by exercise mode and health status. The greatest changes were observed in the first post-exercise samples, with a gradual return to baseline at 24 h. RE caused the greatest responses overall, followed by HIIE, while CME had minimal effect. The metabolic fingerprints of the two groups were separated at 2 h, after HIIE and RE; and at 4 h, after HIIE, with evidence of blunted response to exercise in MetS. Our findings show diverse responses of the urinary metabolic fingerprint to different exercise modes in men with and without metabolic syndrome.

Coffee and green tea consumption in relation to brain tumor risk in a Japanese population

Few prospective studies have investigated the etiology of brain tumor, especially among Asian populations. Both coffee and green tea are popular beverages, but their relation with brain tumor risk, particularly with glioma, has been inconsistent in epidemiological studies. In this study, we evaluated the association between coffee and greed tea intake and brain tumor risk in a Japanese population. We evaluated a cohort of 106,324 subjects (50,438 men and 55,886 women) in the Japan Public Health Center-Based Prospective Study (JPHC Study). Subjects were followed from 1990 for Cohort I and 1993 for Cohort II until December 31, 2012. One hundred and fifty-seven (70 men and 87 women) newly diagnosed cases of brain tumor were identified during the study period. Hazard ratio (HR) and 95% confidence intervals (95%CIs) for the association between coffee or green tea consumption and brain tumor risk were assessed using a Cox proportional hazards regression model. We found a significant inverse association between coffee consumption and brain tumor risk in both total subjects (≥3 cups/day; HR = 0.47, 95%CI = 0.22-0.98) and in women (≥3 cups/day; HR = 0.24, 95%CI = 0.06-0.99), although the number of cases in the highest category was small. Furthermore, glioma risk tended to decrease with higher coffee consumption (≥3 cups/day; HR = 0.54, 95%CI = 0.16-1.80). No association was seen between green tea and brain tumor risk. In conclusion, our study suggested that coffee consumption might reduce the risk of brain tumor, including that of glioma, in the Japanese population.

Anger Traits Associated With Cardiovascular Risk Biomarkers in the Metabolic Syndrome

BACKGROUND

Recent studies have shown that different personality traits contribute to mortality in different subtypes of cardiovascular disease (CVD). Anger traits have been shown to promote the constellation of the metabolic syndrome (MetS), which in turn increases CVD risks.

OBJECTIVE

To determine covariation of anger traits with CVD biomarkers, we examined patients (N = 101; 34 men and 67 women; age, 45.6 ± 13.96 years) in a nationally sampled treatment cohort for MetS in the Ukrainian governmental healthcare system.

METHODS

Data collection was conducted in 2007. Laboratory data of single components of the MetS according to International Diabetes Federation Consensus were dependent measures in regression models with self-reported overt aggressivity and covert hostility in the Buss-Durkee Hostility Inventory and sociodemographic data. Structural equation models (SEMs) were tested.

RESULTS

The SEM results are in favor of a sex-adjusted 2-factor solution R = 0.723), as indicated by equation-level Bentler-Raykov goodness-of-fit coefficients of 0.81 to 0.97 for paths to biological variables. Two latent components, 1 relating to aggressivity and the other to hostility, combine lipid/obesity-related measures and cholesterol-related measures, respectively.

CONCLUSIONS

The SEM results suggest that CVD-risk biomarker variables in this MetS sample (a) associate into 2 distinct profiles and (b) that 1 profile associates with overt anger, whereas the other associates with covert hostility. These results could contribute to more personalized prevention and care in CVD patients.

High-fructose and high-fat feeding correspondingly lead to the development of lysoPC-associated apoptotic cardiomyopathy and adrenergic signaling-related cardiac hypertrophy

BACKGROUND

The heart is a highly adaptive organ that demonstrates remarkable structural, functional, and metabolic remodeling in response to physiological and pathological stimuli. We hypothesize that the heart undergoes differential adaptations in high-fat and high-fructose diet, resulting in a distinct phenotype.

METHODS

High-fat and high-fructose diet-induced obese and non-obese insulin resistance (IR) rat models were used to understand how the heart adapts to long-term (12-week) overnutrition.

RESULTS

Rats fed the high-fat diet developed obese IR, whereas high-fructose diet developed non-obese IR. Obese IR rats developed fibrotic hypertrophy with impairment of preload-independent contractility. The sympathetic and renin-angiotensin-aldosterone (RAA) systems and myocardial adrenergic signaling were activated in obese IR rats. Non-obese IR rats developed apoptotic cardiomyopathy with severe systolic dysfunction. Myocardial calcium cycling regulatory proteins (CCRPs) were dysregulated in non-obese IR rats; specifically, troponin I protein expression was downregulated. Moreover, compared with the controls, lipidomics analysis revealed substantial differences in lipid metabolites in non-obese IR and obese IR rats. The overproduction of lysophosphatidylcholine (lysoPC) and fatty acids was observed in non-obese IR rat hearts. A strong correlation was observed between the myocardial lysoPC and plasma troponin I levels. Treatment of cardiomyocytes with lysoPC resulted in cell death in a dose- and time-dependent manner. The overproduction of myocardial lysoPCs was associated with circulating sPLA2 levels.

CONCLUSION

Obese IR rats developed severe fibrotic hypertrophy with the activation of adrenergic signaling and sympathetic and RAA systems. The sPLA2-lysoPC may play a crucial role in the induction of apoptotic cardiomyopathy in high fructose-induced non-obese IR rats.

Trait anxiety but not state anxiety level associates with biomarkers for hypertension in the metabolic syndrome

Various studies link hypertension with anxiety; however, it remains unclarified if such relations are present in the metabolic syndrome (MetS). We studied cross-sectionally the interrelations of self-reported anxiety (Spielberger STAI), and MetS components in MetS patients. We investigated a nationally sampled treatment cohort for MetS with familial Type 2 diabetes risk. N = 101 patients fulfilling International Diabetes Federation criteria for MetS participated. Both laboratory and nonlaboratory measures were included. Structural equation models (SEM) were adjusted. The final SEM had an R(2)  = .998 with the obesity component linking to waist, BMI, and degree of adiposity, and the hypertension component linking to systolic blood pressure, pulse pressure, total cholesterol, and trait anxiety. For state anxiety, no significant regressive causal path could be estimated. SEM supports the assumption of an interaction of pulse pressure, systolic blood pressure, cholesterol metabolism, and high trait anxiety in the pathophysiology of hypertension in MetS.

Metabolomic insights into the intricate gut microbial-host interaction in the development of obesity and type 2 diabetes

Gut microbiota has recently been proposed as a crucial environmental factor in the development of metabolic diseases such as obesity and type 2 diabetes, mainly due to its contribution in the modulation of several processes including host energy metabolism, gut epithelial permeability, gut peptide hormone secretion, and host inflammatory state. Since the symbiotic interaction between the gut microbiota and the host is essentially reflected in specific metabolic signatures, much expectation is placed on the application of metabolomic approaches to unveil the key mechanisms linking the gut microbiota composition and activity with disease development. The present review aims to summarize the gut microbial-host co-metabolites identified so far by targeted and untargeted metabolomic studies in humans, in association with impaired glucose homeostasis and/or obesity. An alteration of the co-metabolism of bile acids, branched fatty acids, choline, vitamins (i.e., niacin), purines, and phenolic compounds has been associated so far with the obese or diabese phenotype, in respect to healthy controls. Furthermore, anti-diabetic treatments such as metformin and sulfonylurea have been observed to modulate the gut microbiota or at least their metabolic profiles, thereby potentially affecting insulin resistance through indirect mechanisms still unknown. Despite the scarcity of the metabolomic studies currently available on the microbial-host crosstalk, the data-driven results largely confirmed findings independently obtained from in vitro and animal model studies, putting forward the mechanisms underlying the implication of a dysfunctional gut microbiota in the development of metabolic disorders.

Vitamin paradox in obesity: Deficiency or excess?

Since synthetic vitamins were used to fortify food and as supplements in the late 1930s, vitamin intake has significantly increased. This has been accompanied by an increased prevalence of obesity, a condition associated with diabetes, hypertension, cardiovascular disease, asthma and cancer. Paradoxically, obesity is often associated with low levels of fasting serum vitamins, such as folate and vitamin D. Recent studies on folic acid fortification have revealed another paradoxical phenomenon: obesity exhibits low fasting serum but high erythrocyte folate concentrations, with high levels of serum folate oxidation products. High erythrocyte folate status is known to reflect long-term excess folic acid intake, while increased folate oxidation products suggest an increased folate degradation because obesity shows an increased activity of cytochrome P450 2E1, a monooxygenase enzyme that can use folic acid as a substrate. There is also evidence that obesity increases niacin degradation, manifested by increased activity/expression of niacin-degrading enzymes and high levels of niacin metabolites. Moreover, obesity most commonly occurs in those with a low excretory reserve capacity (e.g., due to low birth weight/preterm birth) and/or a low sweat gland activity (black race and physical inactivity). These lines of evidence raise the possibility that low fasting serum vitamin status in obesity may be a compensatory response to chronic excess vitamin intake, rather than vitamin deficiency, and that obesity could be one of the manifestations of chronic vitamin poisoning. In this article, we discuss vitamin paradox in obesity from the perspective of vitamin homeostasis.

Metabolomics in cardiovascular diseases

Cardiovascular diseases (CVDs) are the main cause of death globally. There is a need for the development of specific diagnostic methods, more effective therapeutic procedures as well as drugs, which can decrease the risk of deaths in the course of CVDs. For this reason, better understanding and explanation of molecular pathomechanisms of CVDs are essential. Metabolomics is focused on analysis of metabolites, small molecules which reflect the state of an organism in a certain point of time. Application of metabolomics approach in the investigation of molecular processes responsible for CVDs development may provide valuable information. In this article we overviewed recent reports employing application of untargeted and targeted metabolomic analyses in particular CVDs. Moreover, we focused on applications of various analytical platforms and metabolomics approaches which may contribute to the explanation of the pathomechanisms of different cardiovascular diseases.

Alexithymia as a risk factor for type 2 diabetes mellitus in the metabolic syndrome: a cross-sectional study

Alexithymia is a clinical trait consisting of diminished introspective and interoceptive capacities that has been shown to implicate elevated autonomic outflow and to bias for hypertension. To estimate relative risk associated with alexithymia in the metabolic syndrome (MetS), we conducted a cross-sectional analysis of patients with manifest type 2 diabetes mellitus (T2DM) or familial diabetes risk (N=101; 67 females; age 45.6±13.96) in a nationwide sampled treatment cohort for MetS in the Ukrainian governmental health care system. Laboratory data of single components of the MetS according to International Diabetes Federation Consensus were dependent measures in multivariable regression models with self-reported alexithymia severity (TAS-20) and socio-demographic data. TAS-20 as the sole surviving psychometric predictor for T2DM in the simplest regression equation provided the best model fit: OR 1.073, Z=19.04, (95%CIs 1.065-1.081). For microalbuminuria, the best fitting model was OR 1.030, Z=3.49 (95%CIs 1.013-1.048). TAS-20 predicted also triglyceride level at Wald-χ(2)=1299.27, Z=36.05 (95%CIs 0.052-0.058) and blood pressure maximum at Wald-χ(2)=2309.05, Z=48.05 (95%CIs 2.402-2.606). Our results show that alexithymia severity contributes to MetS by covarying with several of its single components, and that it may be a substantial concurrent indicator of T2DM and cardiovascular risks in MetS.

Introduction to personalized medicine in diabetes mellitus

The world is facing an epidemic rise in diabetes mellitus (DM) incidence, which is challenging health funders, health systems, clinicians, and patients to understand and respond to a flood of research and knowledge. Evidence-based guidelines provide uniform management recommendations for "average" patients that rarely take into account individual variation in susceptibility to DM, to its complications, and responses to pharmacological and lifestyle interventions. Personalized medicine combines bioinformatics with genomic, proteomic, metabolomic, pharmacogenomic ("omics") and other new technologies to explore pathophysiology and to characterize more precisely an individual's risk for disease, as well as response to interventions. In this review we will introduce readers to personalized medicine as applied to DM, in particular the use of clinical, genetic, metabolic, and other markers of risk for DM and its chronic microvascular and macrovascular complications, as well as insights into variations in response to and tolerance of commonly used medications, dietary changes, and exercise. These advances in "omic" information and techniques also provide clues to potential pathophysiological mechanisms underlying DM and its complications.