Endothelin receptor B-deficient mice are protected from high-fat diet-induced metabolic syndrome.

Objective: Endothelin receptor B (ETB) together with ETA mediates cellular effects of endothelin 1 (ET-1), an autocrine and endocrine peptide produced by the endothelium and other cells. It regulates vascular tone and controls kidney function. Metabolic syndrome is due to high caloric intake and is characterized by insulin resistance, dyslipidemia, and white adipose tissue (WAT) accumulation.

A New Biomarker Profiling Strategy for Gut Microbiome Research: Valid Association of Metabolites to Metabolism of Microbiota Detected by Non-Targeted Metabolomics in Human Urine.

The gut microbiome is of tremendous relevance to human health and disease, so it is a hot topic of omics-driven biomedical research. However, a valid identification of gut microbiota-associated molecules in human blood or urine is difficult to achieve. We hypothesize that bowel evacuation is an easy-to-use approach to reveal such metabolites.

Automated LC-MS/MS: Ready for the clinical routine Laboratory?

Background: Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is a sensitive method with high specificity. However, its routine use in the clinical laboratory is hampered by its high complexity and lack of automation. Studies demonstrate excellent analytical performance using the first fully automated LC-MS/MS for 25-hydroxy vitamin D and immunosuppressant drugs (ISD) in hospital routine laboratories.

Ex vivo instability of lipids in whole blood: preanalytical recommendations for clinical lipidomics studies.

Reliability, robustness, and interlaboratory comparability of quantitative measurements is critical for clinical lipidomics studies. Lipids' different ex vivo stability in blood bears the risk of misinterpretation of data. Clear recommendations for the process of blood sample collection are required.

Exercise-Induced N-Lactoylphenylalanine Predicts Adipose Tissue Loss during Endurance Training in Overweight and Obese Humans.

Physical exercise is a powerful measure to prevent cardiometabolic diseases. However, the individual response to lifestyle interventions is variable and cannot, to date, be predicted. N-Lactoylphenylalanine (Lac-Phe) produced during exercise has recently been shown to mediate weight loss in obese mice.

The Acute Cytokine Response to 30-Minute Exercise Bouts Before and After 8-Week Endurance Training in Individuals With Obesity.

Context: One acute bout of exercise leads to a rapid increase in the systemic cytokine concentration. Regular exercise might alter the cytokine response, in particular in beforehand untrained and obese individuals.

Objective: Using a proximity extension assay, we studied the effects of acute exercise as well as endurance training on a panel of 92 cytokines related to inflammation.

Diagnostic Performance of Sex-Specific Modified Metabolite Patterns in Urine for Screening of Prediabetes.

Aims/hypothesis: Large-scale prediabetes screening is still a challenge since fasting blood glucose and HbA as the long-standing, recommended analytes have only moderate diagnostic sensitivity, and the practicability of the oral glucose tolerance test for population-based strategies is limited. To tackle this issue and to identify reliable diagnostic patterns, we developed an innovative metabolomics-based strategy deviating from common concepts by employing urine instead of blood samples, searching for sex-specific biomarkers, and focusing on modified metabolites.

Methods: Non-targeted, modification group-assisted metabolomics by liquid chromatography-mass spectrometry (LC-MS) was applied to second morning urine samples of 340 individuals from a prediabetes cohort.

Signals from the Circle: Tricarboxylic Acid Cycle Intermediates as Myometabokines.

Regular physical activity is an effective strategy to prevent and ameliorate aging-associated diseases. In particular, training increases muscle performance and improves whole-body metabolism. Since exercise affects the whole organism, it has countless health benefits.

Comparison of the metabolome in urine prior and eight weeks after radical prostatectomy uncovers pathologic and molecular features of prostate cancer.

Prostate cancer (PCa) is associated with cellular metabolism alterations leading to changes of the metabolome. So far, studies investigating these alterations mainly focused on comparisons of metabolite profiles of PCa patients and healthy controls. In the present study we compared for the first time metabolite profiles in a significant number of paired urine samples collected before and eight weeks after radical prostatectomy (rPX) in 34 patients with PCa.

Systematic, Modifying Group-Assisted Strategy Expanding Coverage of Metabolite Annotation in Liquid Chromatography-Mass Spectrometry-Based Nontargeted Metabolomics Studies.

From microbes to human beings, nontargeted metabolic profiling by liquid chromatography (LC)-mass spectrometry (MS) has been commonly used to investigate metabolic alterations. Still, a major challenge is the annotation of metabolites from thousands of detected features. The aim of our research was to go beyond coverage of metabolite annotation in common nontargeted metabolomics studies by an integrated multistep strategy applying data-dependent acquisition (DDA)-based ultrahigh-performance liquid chromatography (UHPLC)-high-resolution mass spectrometry (HRMS) analysis followed by comprehensive neutral loss matches for characteristic metabolite modifications and database searches in a successive manner.

Evaluation of the first immunosuppressive drug assay available on a fully automated LC-MS/MS-based clinical analyzer suggests a new era in laboratory medicine.

Objectives: Due to its high specificity, liquid chromatography-tandem mass spectrometry (LC-MS/MS) is considered the gold standard in diagnostic areas such as therapeutic monitoring of immunosuppressive drugs (ISDs). However, many laboratories still rely on immunoassays for ISD quantification in a tradeoff between analytical performance and the advantages of fully automated analyzers - shorter turnaround times, greater ease of use, and 24/7 availability.

Methods: The LC-MS/MS-based Thermo Scientific™ Cascadion™ SM Immunosuppressant Panel was evaluated for >6 months in the routine laboratory of a university hospital.

Human Prostate Cancer is Characterized by an Increase in Urea Cycle Metabolites.

Despite it being the most common incident of cancer among men, the pathophysiological mechanisms contributing to prostate cancer (PCa) are still poorly understood. Altered mitochondrial metabolism is postulated to play a role in the development of PCa. To determine the key metabolites (which included mitochondrial oncometabolites), benign prostatic and cancer tissues of patients with PCa were analyzed using capillary electrophoresis and liquid chromatography coupled with mass spectrometry.

Identification and regulation of the xenometabolite derivatives - and -3,4-methylene-heptanoylcarnitine in plasma and skeletal muscle of exercising humans.

Little is known about xenometabolites in human metabolism, particularly under exercising conditions. Previously, an exercise-modifiable, likely xenometabolite derivative, -3,4-methylene-heptanoylcarnitine, was reported in human plasma. Here, we identified -3,4-methylene-heptanoylcarnitine, and its -isomer, in plasma and skeletal muscle by liquid chromatography-mass spectrometry.

Muscle-Liver Substrate Fluxes in Exercising Humans and Potential Effects on Hepatic Metabolism.

Context: The liver is crucial to maintain energy homeostasis during exercise. Skeletal muscle-derived metabolites can contribute to the regulation of hepatic metabolism.

Objective: We aim to elucidate which metabolites are released from the working muscles and taken up by the liver in exercising humans and their potential influence on hepatic function.

Linking bioenergetic function of mitochondria to tissue-specific molecular fingerprints.

Mitochondria are dynamic organelles with diverse functions in tissues such as liver and skeletal muscle. To unravel the mitochondrial contribution to tissue-specific physiology, we performed a systematic comparison of the mitochondrial proteome and lipidome of mice and assessed the consequences hereof for respiration. Liver and skeletal muscle mitochondrial protein composition was studied by data-independent ultra-high-performance (UHP)LC-MS/MS-proteomics, and lipid profiles were compared by UHPLC-MS/MS lipidomics.

Hepatokines-a novel group of exercise factors.

Regular physical activity not only improves the exercise capacity of the skeletal muscle performing the contractions, but it is beneficial for the whole body. An extensive search for "exercise factors" mediating these beneficial effects has been going on for decades. Particularly skeletal muscle tissue has been investigated as a source of circulating exercise factors, and several myokines have been identified.

Serum or plasma, what is the difference? Investigations to facilitate the sample material selection decision making process for metabolomics studies and beyond.

In analytical chemistry serum as well as plasma are recommended as sample material of choice. However, blood processing for the generation of serum or plasma is rather different. Whether plasma or serum is the preferable sample material is still controversial discussed.

Dissociation of Fatty Liver and Insulin Resistance in I148M PNPLA3 Carriers: Differences in Diacylglycerol (DAG) FA18:1 Lipid Species as a Possible Explanation.

Fatty liver is tightly associated with insulin resistance and the development of type 2 diabetes. I148M variant in patatin-like phospholipase domain-containing protein 3 (PNPLA3) gene is associated with high liver fat but normal insulin sensitivity. The underlying mechanism of the disassociation between high liver fat but normal insulin sensitivity remains obscure.

A Vitamin E-Enriched Antioxidant Diet Interferes with the Acute Adaptation of the Liver to Physical Exercise in Mice.

Physical exercise is beneficial for general health and is an effective treatment for metabolic disorders. Vitamin E is widely used as dietary supplement and is considered to improve non-alcoholic fatty liver disease by reducing inflammation and dyslipidemia. However, increased vitamin E intake may interfere with adaptation to exercise training.

Quality Control of Serum and Plasma by Quantification of (4E,14Z)-Sphingadienine-C18-1-Phosphate Uncovers Common Preanalytical Errors During Handling of Whole Blood.

Background: Nonadherence to standard operating procedures (SOPs) during handling and processing of whole blood is one of the most frequent causes affecting the quality of serum and plasma. Yet, the quality of blood samples is of the utmost importance for reliable, conclusive research findings, valid diagnostics, and appropriate therapeutic decisions.

Methods: UHPLC-MS-driven nontargeted metabolomics was applied to identify biomarkers that reflected time to processing of blood samples, and a targeted UHPLC-MS analysis was used to quantify and validate these biomarkers.

Mechanical Bowel Preparation (MBP) Prior to Elective Colorectal Resections in Crohn's Disease Patients.

Background: Studies addressing the role of mechanical bowel preparation (MBP) in Crohn's disease (CD) patients are lacking.

Methods: Consecutive elective colorectal resections for CD have been included in the present analysis. Exclusion criteria were small bowel resections not including colon, urgent surgeries, surgeries for cancer, and abdominoperineal resections for perianal disease.

Point mutation of Ffar1 abrogates fatty acid-dependent insulin secretion, but protects against HFD-induced glucose intolerance.

Objective: The fatty acid receptor 1 (FFAR1/GPR40) mediates fatty acid-dependent augmentation of glucose-induced insulin secretion (GIIS) in pancreatic β-cells. Genetically engineered Ffar1-knockout/congenic mice univocally displayed impaired fatty acid-mediated insulin secretion, but in vivo experiments delivered controversial results regarding the function of FFAR1 in glucose homeostasis and liver steatosis. This study presents a new coisogenic mouse model carrying a point mutation in Ffar1 with functional consequence.