A Multi-Omics Study Revealing the Metabolic Effects of Estrogen in Liver Cancer Cells HepG2.

Hepatocellular carcinoma (HCC) that is triggered by metabolic defects is one of the most malignant liver cancers. A much higher incidence of HCC among men than women suggests the protective roles of estrogen in HCC development and progression. To begin to understand the mechanisms involving estrogenic metabolic effects, we compared cell number, viability, cytotoxicity, and apoptosis among HCC-derived HepG2 cells that were treated with different concentrations of 2-deoxy-d-glucose (2-DG) that blocks glucose metabolism, oxamate that inhibits lactate dehydrogenase and glycolysis, or oligomycin that blocks ATP synthesis and mitochondrial oxidative phosphorylation.

Bridging Targeted and Untargeted Mass Spectrometry-Based Metabolomics via Hybrid Approaches.

This mini-review aims to discuss the development and applications of mass spectrometry (MS)-based hybrid approaches in metabolomics. Several recently developed hybrid approaches are introduced. Then, the overall workflow, frequently used instruments, data handling strategies, and applications are compared and their pros and cons are summarized.

Development and application of time staggered/mass staggered-globally optimized targeted mass spectrometry.

The emerging requests for handling complex samples in system biology studies highlighted the need to expand the metabolite coverage in metabolomics analysis and to take advantage of the quantitative and targeted assays. Here, we developed a novel workflow to integrate time staggered or mass staggered scan methods with globally optimized targeted-mass spectrometry (GOT-MS), to enable broad metabolites coverage with better stability, repeatability, and quantitative capability. To establish these methods, two scheduled selected reaction monitoring (SRM) methods, time staggered and mass staggered approaches, were configured to achieve optimal sensitivity and scan speed and were combined with the GOT-MS strategy.

Metabolic shift of Staphylococcus aureus under sublethal dose of methicillin in the presence of glucose.

Traditional strategies in developing novel drugs to treat antibiotic-resistant S. aureus have not been very successful to date, therefore, there is an urgent need for creative usage of existing agents that can treat and control S. aureus infection.

Rapid differentiation of Lactobacillus species via metabolic profiling.

Lactobacillus, the major genus of lactic acid bacteria group, plays functional roles in the human body, for example, convert sugars to lactic acid. They are the significant microbiota which can be found at a number of human body sites, such as the digestive system, urinary system, and genital system. A number of Lactobacillus species are often used as probiotics and can benefit host health when administered in adequate amounts.

A quantitative metabolomics study of bacterial metabolites in different domains.

Absolute metabolite concentrations are essential information for quantitative metabolomics studies, as concentrations are closely related to metabolic reactions, enzyme kinetics and other important biological activities. A well-performed metabolites extraction procedure, a reliable detection method, and a robust quantitative approach are all critical factors for obtaining absolute metabolite concentrations. Here, we used a HPLC-MS/MS based platform to successfully develop a C-labeled quantitative metabolomics approach, and applied this novel method to quantify bacterial metabolite concentrations in three different domains (i.

Metabolic signature of the aging eye in mice.

Aging is a major risk factor for age-related ocular diseases including age-related macular degeneration in the retina and retinal pigment epithelium (RPE), cataracts in the lens, glaucoma in the optic nerve, and dry eye syndrome in the cornea. We used targeted metabolomics to analyze metabolites from young (6 weeks) and old (73 weeks) eyes in C57 BL6/J mice. Old mice had diminished electroretinogram responses and decreased number of photoreceptors in their retinas.

Comparative Metabolomics Elucidates Postprandial Metabolic Modifications in Plasma of Obese Individuals with Metabolic Syndrome.

Although higher intakes of dairy milk are associated with a lower risk of metabolic syndrome (MetS), the underlying protective mechanism remains unclear. This study investigated the dynamic metabolic profile shift following the ingestion of low-fat milk or an isocaloric volume of rice milk in obese individuals with metabolic syndrome (MetS). In a randomized, double-blind, crossover study, postprandial plasma samples ( n = 266) were collected from 19 MetS participants.

Comparative metabolomics revealing Staphylococcus aureus metabolic response to different antibiotics.

It is known that changes in bacterial metabolism can contribute to the modulation of bacterial susceptibility to antibiotics. Understanding how bacterial metabolism is impacted by antibiotics may improve our understanding of the antibiotic mechanism of actions from a metabolic perspective. Here, we utilized a mass spectrometry-based targeted metabolic profiling technique to characterize the metabolome of a pair of isogenic methicillin-susceptible and resistant Staphylococcus aureus (MSSA and MRSA) strains RN450 and 450M treated with the sublethal dose of three antibiotics from different classes (β-lactams, aminoglycosides and quinolones).

Comparing the impact of ultrafine particles from petrodiesel and biodiesel combustion to bacterial metabolism by targeted HPLC-MS/MS metabolic profiling.

Alterations of gut bacterial metabolism play an important role in their host metabolism, and can result in diseases such as obesity and diabetes. While many factors were discovered influencing the gut bacterial metabolism, exposure to ultrafine particles (UFPs) from engine combustions were recently proposed to be a potential risk factor for the perturbation of gut bacterial metabolism, and consequentially to obesity and diabetes development. This study focused on evaluation of how UFPs from diesel engine combustions impact gut bacterial metabolism.

Targeted High Performance Liquid Chromatography Tandem Mass Spectrometry-based Metabolomics differentiates metabolic syndrome from obesity.

Both obesity and the metabolic syndrome are risk factors for type 2 diabetes and cardiovascular disease. Identification of novel biomarkers are needed to distinguish metabolic syndrome from equally obese individuals in order to direct them to early interventions that reduce their risk of developing further health problems. We utilized mass spectrometry-based targeted metabolic profiling of 221 metabolites to evaluate the associations between metabolite profiles and established metabolic syndrome criteria (i.

Evaluating metabolic response to light exposure in Lactobacillus species via targeted metabolic profiling.

This study reported metabolic profiles of three representative strains from Lactobacillus species, and explored their metabolic response to visible light exposure. We utilized strains from three Lactobacillus species, Lactobacillus acidophilus, Lactobacillus fermentum and Lactobacillus delbrueckii as our model bacteria and applied mass spectrometry base targeted metabolomics to specifically investigate 221 metabolites within multiple metabolic pathways. Similar and diverse metabolome from three tested strains were discovered.

Development and validation of a liquid chromatography/tandem mass spectrometry assay for the simultaneous determination of dabigatran etexilate, intermediate metabolite and dabigatran in 50μL rat plasma and its application to pharmacokinetic study.

A simple, rapid and specific high performance liquid chromatography-electrospray ionization tandem mass spectrometry method was developed for simultaneous determination of dabigatran etexilate (BIBR 1048 MS), the intermediate metabolite (BIBR 1087 SE) and dabigatran (BIBR 953 ZW). In this method, a stacked protein precipitation with methanol was performed in Sirocco 96-well filtration plates to extract analytes using only 50μL plasma. The analysis was performed on an Ultimate TM XB-C18 (4.

Isolation and purification of diastereoisomeric flavonolignans from silymarin by binary-column recycling preparative high-performance liquid chromatography.

Silymarin extracted from Silybum marianum (L.) Gaertn consists of a large number of flavonolignans, of which diastereoisomeric flavonolignans including silybin A and silybin B, and isosilybin A and isosilybin B are the main bioactive components, whose preparation from the crude extracts is still a difficult task. In this work, binary-column recycling preparative high-performance liquid chromatography systems without sample loop trapping, where two columns were switched alternately via one or two six-port switching valves, were established and successfully applied to the isolation and purification of the four diastereoisomeric flavonolignans from silymarin.