PubMed

Related Articles A novel method to detect intracellular metabolite alterations in MCF-7 cells by doxorubicin induced cell death. Metabolomics. 2021 Jan 03;17(1):3 Authors: Kumar A, Patel S, Bhatkar D, Sarode SC, Sharma NK Abstract BACKGROUND: Metabolic reprogramming within cancer cells has been recognized as a potential barrier to chemotherapy. Additionally, metabolic tumor heterogeneity is the one of factors behind discernible hallmarks such as drug resistance, relapse of the tumor and the formation of secondary tumors. METHODS: In this paper, cell-based assays including PI/annexin V staining and immunoblot assay were performed to show the apoptotic cell death in MCF-7 cells treated with DOX. Further, MCF-7 cells were lysed in a hypotonic buffer and the whole cell lysate was purified by a novel and specifically designed metabolite (~ 100 to 1000 Da) fractionation system called vertical tube gel electrophoresis (VTGE). Further, purified intracellular metabolites were subjected to identification by LC-HRMS technique. RESULTS: Cleaved PARP 1 in MCF-7 cells treated with DOX was observed in the present study. Concomitantly, data showed the absence of active caspase 3 in MCF-7 cells. Novel findings are to identify key intracellular metabolites assisted by VTGE system that include lipid (CDP-DG, phytosphingosine, dodecanamide), non-lipid (N-acetyl-D-glucosamine, N1-acetylspermidine and gamma-L-glutamyl-L-cysteine) and tripeptide metabolites in MCF-7 cells treated by DOX. Interestingly, we reported the first evidence of doxorubicinone, an aglycone form of DOX in MCF-7 cells that are potentially linked to the mechanism of cell death in MCF-7 cells. CONCLUSION: This paper reported novel methods and processes that involve VTGE system based purification of hypotonically lysed novel intracellular metabolites of MCF-7 cells treated by DOX. Here, these identified intracellular metabolites corroborate to caspase 3 independent and mitochondria induced apoptotic cell death in MCF-7 cells. Finally, these findings validate a proof of concept on the applications of novel VTGE assisted purification and analysis of intracellular metabolites from various cell culture models. PMID: 33389242 [PubMed - as supplied by publisher]

Related Articles Osmolality-based normalization enhances statistical discrimination of untargeted metabolomic urine analysis: results from a comparative study. Metabolomics. 2021 Jan 02;17(1):2 Authors: Mervant L, Tremblay-Franco M, Jamin EL, Kesse-Guyot E, Galan P, Martin JF, Guéraud F, Debrauwer L Abstract INTRODUCTION: Because of its ease of collection, urine is one of the most commonly used matrices for metabolomics studies. However, unlike other biofluids, urine exhibits tremendous variability that can introduce confounding inconsistency during result interpretation. Despite many existing techniques to normalize urine samples, there is still no consensus on either which method is most appropriate or how to evaluate these methods. OBJECTIVES: To investigate the impact of several methods and combinations of methods conventionally used in urine metabolomics on the statistical discrimination of two groups in a simple metabolomics study. METHODS: We applied 14 different strategies of normalization to forty urine samples analysed by liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS). To evaluate the impact of these different strategies, we relied on the ability of each method to reduce confounding variability while retaining variability of interest, as well as the predictability of statistical models. RESULTS: Among all tested normalization methods, osmolality-based normalization gave the best results. Moreover, we demonstrated that normalization using a specific dilution prior to the analysis outperformed post-acquisition normalization. We also demonstrated that the combination of various normalization methods does not necessarily improve statistical discrimination. CONCLUSIONS: This study re-emphasized the importance of normalizing urine samples for metabolomics studies. In addition, it appeared that the choice of method had a significant impact on result quality. Consequently, we suggest osmolality-based normalization as the best method for normalizing urine samples. TRIAL REGISTRATION NUMBER: NCT03335644. PMID: 33389209 [PubMed - as supplied by publisher]

Related Articles Serum metabolic profiling analysis of gout patients based on UPLC-Q-TOF/MS. Clin Chim Acta. 2020 Dec 31;: Authors: Zhong Z, Huang Y, Huang Q, Zheng S, Huang Z, Deng W, Li T Abstract BACKGROUND: Gout is a common kind of inflammatory arthritis with metabolic disorders. However, the detailed pathogenesis of gout is complex and not fully clear. We investigated the serum metabolic profiling of gout patients by ultra-performance liquid chromatograph quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). METHODS: Serum metabolites were extracted from 31 gout patients and 31 healthy controls. Metabolite extracts were analyzed in negative mode by UPLC-Q-TOF/MS for global metabolomics. Principal components analysis (PCA), orthogonal partial least squares-discriminant analysis (OPLS-DA) and hierarchical clustering analysis were performed to detect different compounds between the 2 groups. Receiver operating characteristic (ROC) curve analysis and pathway analysis of the different metabolites were conducted. RESULTS: A total of 9192 compounds were detected, of which 138 significantly different compounds were selected, according to the criteria of (Variable importance in projection (VIP)>3). Hierarchical clustering analysis showed that the relative levels of the differential compounds were different between the 2 groups. Ninety-one reliable metabolites matching the human metabolome database (HMDB) were confirmed. ROC curve results revealed that 4-hydroxytriazolam, urate and bilirubin exerted higher AUC values. Pathway analysis indicated that the significantly different metabolites were mainly involved in primary bile acid biosynthesis, purine metabolism and glycerophospholipid metabolism. CONCLUSIONS: The serum metabolic profiling of gout patients was significantly different from healthy subjects based on UPLC-Q-TOF/MS. Bilirubin was the potential biomarker. Primary bile acid biosynthesis may be a novel metabolic pathway of gout. PMID: 33388309 [PubMed - as supplied by publisher]

Related Articles Transcriptomic and proteomic profiling revealed reprogramming of carbon metabolism in acetate-grown human pathogen Candida glabrata. J Biomed Sci. 2021 Jan 02;28(1):1 Authors: Chew SY, Brown AJP, Lau BYC, Cheah YK, Ho KL, Sandai D, Yahaya H, Than LTL Abstract BACKGROUND: Emergence of Candida glabrata, which causes potential life-threatening invasive candidiasis, has been widely associated with high morbidity and mortality. In order to cause disease in vivo, a robust and highly efficient metabolic adaptation is crucial for the survival of this fungal pathogen in human host. In fact, reprogramming of the carbon metabolism is believed to be indispensable for phagocytosed C. glabrata within glucose deprivation condition during infection. METHODS: In this study, the metabolic responses of C. glabrata under acetate growth condition was explored using high-throughput transcriptomic and proteomic approaches. RESULTS: Collectively, a total of 1482 transcripts (26.96%) and 242 proteins (24.69%) were significantly up- or down-regulated. Both transcriptome and proteome data revealed that the regulation of alternative carbon metabolism in C. glabrata resembled other fungal pathogens such as Candida albicans and Cryptococcus neoformans, with up-regulation of many proteins and transcripts from the glyoxylate cycle and gluconeogenesis, namely isocitrate lyase (ICL1), malate synthase (MLS1), phosphoenolpyruvate carboxykinase (PCK1) and fructose 1,6-biphosphatase (FBP1). In the absence of glucose, C. glabrata shifted its metabolism from glucose catabolism to anabolism of glucose intermediates from the available carbon source. This observation essentially suggests that the glyoxylate cycle and gluconeogenesis are potentially critical for the survival of phagocytosed C. glabrata within the glucose-deficient macrophages. CONCLUSION: Here, we presented the first global metabolic responses of C. glabrata to alternative carbon source using transcriptomic and proteomic approaches. These findings implicated that reprogramming of the alternative carbon metabolism during glucose deprivation could enhance the survival and persistence of C. glabrata within the host. PMID: 33388061 [PubMed - as supplied by publisher]

Related Articles Analysis of the metabolic switch induced by the spirulina peptide SP6 in high fat diet ApoE-/- mice model: A direct infusion FT-ICR-MS based approach. J Pharm Biomed Anal. 2020 Dec 24;195:113865 Authors: Sommella E, Carrizzo A, Merciai F, Di Sarno V, Carbone D, De Lucia M, Musella S, Vecchione C, Campiglia P Abstract Atherosclerosis, dyslipidemia and hypertension are comorbid diseases often found in combination. Among different pharmacological approaches the employment of natural multifunctional peptides is an attractive option as side therapy. Mass spectrometry-based metabolomics provide valuable information on metabolic changes and can be useful to elucidate peptide pharmacodynamics. In this this work we performed a preliminary investigation on the potential effect of a recently characterized Spirulina platensis peptide named SP6 (GIVAGDVTPI) on the modulation of metabolism in a high fat diet ApoE-/- mice atherosclerotic model. A direct infusion Fourier transform ion cyclotron resonance mass spectrometry (DI-FT-ICR-MS) approach was used to elucidate polar and non-polar metabolites extracted by mice plasma following four weeks SP6 treatment. The method delivered fast analysis time, repeatability, high mass accuracy and resolution for unambiguous molecular formula assignment. Multivariate statistical analysis (PLS-DA) highlighted a clear class separation, revealing the alteration of numerous metabolites levels belonging to different classes. In particular sphingolipids, glycerophospholipids, TCA cycle intermediates, and amino acids, which are key players in the atherosclerotic process and progression, were upregulated in saline alone HFD ApoE-/- group, while were sensibly decreased after treatment with SP6 peptide. These results could open the way to further, large-scale, investigation of SP6 peptide effects in the regulation of atherosclerotic disease development and progression, and show the potential of DI-FT-ICR as fast analytical tool to take snaphshots of metabolic changes before moving to targeted MS-based approaches. PMID: 33387838 [PubMed - as supplied by publisher]

Related Articles Impacts of manganese bio-based nanocomposites on phytochemical classification, growth and physiological responses of Hypericum perforatum L. shoot cultures. Ecotoxicol Environ Saf. 2020 Dec 30;209:111841 Authors: Jafarirad S, Kosari-Nasab M, Mohammadpour Tavana R, Mahjouri S, Ebadollahi R Abstract We report a new green route for preparing MnO2/perlite nanocomposites (NCs) by leaf extract of Hypericum perforatum. Characterization of the physicochemical properties of the MnO2/perlite-NCs was performed using XRD, FESEM, EDX, FT-IR, and DLS techniques. Furthermore, their effects on the phytochemical classification and growth parameters of H. perforatum shoot cultures were assessed. According to the FESEM image, the synthesized spherical MnO2 nanoparticles on the sheet-like structure of nano-perlite were formed, ranging about 20-50 nm. In addition, based on the EDX spectra, the elemental analysis showed the presence of Carbon, Oxygen, Silicon, Aluminum, and Manganese elements in the as-synthesized MnO2/perlite-NCs. Biological studies confirmed that nano-perlite and MnO2/perlite-NCs were non-toxic to H. perforatum shoot cultures and showed positive effects on plant growth in specific concentrations. Overall, phytochemical classification demonstrated that the terpenoids decreased in the evaluated treatments, while hypericin and pseudohypericin were increased in some treatments (25, 50 and 150 mg/L of nano-perlite) relative to control. Metabolomics results suggested that both nano-perlite and MnO2/perlite-NCs can be used as elicitors and new nanofertilizers for generating some secondary metabolites. PMID: 33387772 [PubMed - as supplied by publisher]

Related Articles Mitochondrial dysfunction as a mechanistic biomarker in patients with Non-Alcoholic fatty liver disease (NAFLD). Mitochondrion. 2020 Dec 30;: Authors: Ajaz S, McPhail MJ, Gnudi L, Trovato FM, Mujib S, Napoli S, Carey I, Agarwal K Abstract BACKGROUND: Dysfunctional metabolism lies at the centre of the pathogenesis for Non-Alcoholic Fatty Liver Disease (NAFLD) and involves mitochondrial dysfunction, lipid dysmetabolism and oxidative stress. This study, for the first time, explores real-time energy changes in peripheral blood and corresponding metabolite changes, to investigate whether mitochondria-related immunometabolic biomarkers can predict progression in NAFLD. METHODS: Thirty subjects divided into 3 groups were assessed: NAFLD with biopsy-proven mild fibrosis (n=10), severe fibrosis (n=10) and healthy controls (HC, n=10). Mitochondrial functional analysis was performed in a Seahorse XFp analyzer in live peripheral blood mononuclear cells (PBMCs). Global metabolomics quantified a broad range of human plasma metabolites. Mitochondrial carbamoyl phosphate synthase 1(CPS-1), Ornithine transcarbamoylase (OTC), Fibroblast growth factor-21 (FGF-21) and a range of cytokines in plasma were measured by ELISA. RESULTS: NAFLD patients with severe fibrosis demonstrated reduced maximal respiration (106 ± 25 versus 242 ± 62, p < 0.05) and reserve capacity (56 ± 16 versus 184 ± 42, p = 0.006) compared to mild/moderate fibrosis. Comparing mild/moderate vs severe liver fibrosis in patients with NAFLD, 14 out of 493 quantified metabolites were significantly changed (p < 0.05). Most of the amino acids modulated were the urea cycle (UC) components which included citrulline/ornithine ratio, arginine and glutamate. Plasma levels of CPS-1 and FGF-21 were significantly higher mild versus severe fibrosis in NAFLD patients. This novel panel generated an area under the ROC of 0.95, sensitivity of 100% and specificity 80% and p = 0.0007 (F1-F2 versus F3-F4). CONCLUSION: Progression in NAFLD is associated with mitochondrial dysfunction and changes in metabolites associated with the urea cycle. We demonstrate a unique panel of mitochondrial-based, signatures which differentiate between stages of NAFLD. Lay summary Mitochondrial dysfunction in peripheral cells along with alterations in metabolites of urea cycle act as a sensor of hepatocyte mitochondrial damage. These changes can be measured in blood and together represent a unique panel of biomarkers for progression of fibrosis in NAFLD. PMID: 33387664 [PubMed - as supplied by publisher]

Related Articles Metabolic Reprogramming: A Driver of Cigarette Smoke-Induced Inflammatory Lung Diseases. Free Radic Biol Med. 2020 Dec 30;: Authors: Li L, Yang DC, Chen CH Abstract Cigarette smoking is a well-known risk factor for pulmonary diseases, including chronic obstructive pulmonary disease (COPD), asthma and pulmonary fibrosis. Despite major progress in dissecting the mechanisms associated with disease development and progression, findings only represent one aspect of multifaceted disease. A crucial consequence of this approach is that many therapeutic treatments often fail to improve or reverse the disease state as other conditions and variables are insufficiently considered. To expand our understanding of pulmonary diseases, omics approaches, particularly metabolomics, has been emerging in the field. This strategy has been applied to identify putative biomarkers and novel mechanistic insights. In this review, we discuss metabolic profiles of patients with COPD, asthma, and idiopathic pulmonary fibrosis (IPF) with a focus on the direct effects of cigarette smoking in altering metabolic regulation. We next present cell- and animal-based experiments and point out the therapeutic potential of targeting metabolic reprogramming in inflammatory lung diseases. In addition, the obstacles in translating these findings into clinical practice, including potential adverse effects and limited pharmacological efficacy, are also addressed. PMID: 33387604 [PubMed - as supplied by publisher]

Related Articles Predicting changes in renal metabolism after compound exposure with a genome-scale metabolic model. Toxicol Appl Pharmacol. 2020 Dec 30;:115390 Authors: Rawls KD, Dougherty BV, Vinnakota KC, Pannala VR, Wallqvist A, Kolling GL, Papin JA Abstract The kidneys are metabolically active organs with importance in several physiological tasks such as the secretion of soluble wastes into the urine and synthesizing glucose and oxidizing fatty acids for energy in fasting (non-fed) conditions. Once damaged, the metabolic capability of the kidneys becomes altered. Here, we define metabolic tasks in a computational modeling framework to capture kidney function in an update to the iRno network reconstruction of rat metabolism using literature-based evidence. To demonstrate the utility of iRno for predicting kidney function, we exposed primary rat renal proximal tubule epithelial cells to four compounds with varying levels of nephrotoxicity (acetaminophen, gentamicin, 2,3,7,8-tetrachlorodibenzodioxin, and trichloroethylene) for six and twenty-four hours, and collected transcriptomics and metabolomics data to measure the metabolic effects of compound exposure. For the transcriptomics data, we observed changes in fatty acid metabolism and amino acid metabolism, as well as changes in existing markers of kidney function such as Clu (clusterin). The iRno metabolic network reconstruction was used to predict alterations in these same pathways after integrating transcriptomics data and was able to distinguish between select compound-specific effects on the proximal tubule epithelial cells. Genome-scale metabolic network reconstructions with coupled omics data can be used to predict changes in metabolism as a step towards identifying novel metabolic biomarkers of kidney function and dysfunction. PMID: 33387578 [PubMed - as supplied by publisher]

Related Articles Altered gut microbial metabolism of essential nutrients in primary sclerosing cholangitis. Gastroenterology. 2020 Dec 30;: Authors: Kummen M, Thingholm LB, Rühlemann MC, Holm K, Hansen SH, Moitinho-Silva L, Liwinski T, Zenouzi R, Storm-Larsen C, Midttun Ø, McCann A, Ueland PM, Høivik ML, Vesterhus M, Trøseid M, Laudes M, Lieb W, Karlsen TH, Bang C, Schramm C, Franke A, Hov JR Abstract BACKGROUND AND AIMS: To influence host and disease phenotype, compositional microbiome changes, which have been demonstrated in patients with primary sclerosing cholangitis (PSC), must be accompanied by functional changes. We therefore aimed to characterize the genetic potential of the gut microbiome in PSC compared to healthy controls (HCs) and inflammatory bowel disease (IBD). METHODS: Fecal DNA from two cohorts (one Norwegian and one German), in total comprising 136 patients with PSC (58% with IBD), 158 HCs and 93 IBD patients without PSC were subjected to metagenomic shotgun sequencing, generating 17 billion paired end sequences, which were processed using HUMAnN2 and MetaPhlAn2, and analyzed using generalized linear models and random effects meta-analyses. RESULTS: PSC patients had fewer microbial genes compared to HC (P<.0001). Compared to HC, PSC patients showed enrichment and increased prevalence of Clostridium species, and a depletion of e.g., Eubacterium spp. and Ruminococcus obeum. Patients with PSC showed marked differences in the abundance of genes related to vitamin B6 synthesis and branched chain amino acid (BCAA) synthesis (Qfdr<.05). Targeted metabolomics of plasma from an independent set of PSC patients and controls found reduced concentrations of vitamin B6 and BCAAs in PSC (P<.0001), which strongly associated with reduced liver transplantation-free survival (log-rank P<.001). No taxonomic or functional differences were detected between PSC patients with and without IBD. CONCLUSION: The gut microbiome of PSC patients exhibits large functional differences compared to HC, including microbial metabolism of essential nutrients. Alterations in related circulating metabolites associated with disease course, suggesting that microbial functions may be relevant for the disease process in PSC. PMID: 33387530 [PubMed - as supplied by publisher]

Related Articles Comparative metabolomics reveals key pathways associated with the synergistic activity of polymyxin B and rifampicin combination against multidrug-resistant Acinetobacter baumannii. Biochem Pharmacol. 2020 Dec 30;:114400 Authors: Zhao J, Han ML, Zhu Y, Lin YW, Wang YW, Lu J, Hu Y, Tony Zhou Q, Velkov T, Li J Abstract Multidrug-resistant (MDR) Acinetobacter baumannii presents a critical challenge to human health worldwide and polymyxins are increasingly used as a last-line therapy. Due to the rapid emergence of resistance during polymyxin monotherapy, synergistic combinations (e.g. with rifampicin) are recommended to treat A. baumannii infections. However, most combination therapies are empirical, owing to a dearth of understanding on the mechanism of synergistic antibacterial killing. In the present study, we employed metabolomics to investigate the synergy mechanism of polymyxin B-rifampicin against A. baumannii AB5075, an MDR clinical isolate. The metabolomes of A. baumannii AB5075 were compared at 1 and 4 h following treatments with polymyxin B alone (0.75 mg/L, i.e. 3×MIC), rifampicin alone (1 mg/L, i.e. 0.25×MIC) and their combination. Polymyxin B monotherapy significantly perturbed glycerophospholipid and fatty acid metabolism at 1 h, reflecting its activity on bacterial outer membrane. Rifampicin monotherapy significantly perturbed glycerophospholipid, nucleotide and amino acid metabolism, which are related to the inhibition of RNA synthesis. The combination treatment significantly perturbed the metabolism of nucleotides, amino acids, fatty acids and glycerophospholipids at 1 and 4 h. Notably, the intermediate metabolite pools from pentose phosphate pathway were exclusively enhanced by the combination, while most metabolites from the nucleotide and amino acid biosynthesis pathways were significantly decreased. Overall, the synergistic activity of the combination was initially driven by polymyxin B which impacted pathways associated with outer membrane biogenesis; and subsequent effects were mainly attributed to rifampicin via the inhibition of RNA synthesis. This study is the first to reveal the synergistic killing mechanism of the polymyxin-rifampicin combination against polymyxin-susceptible MDR A. baumannii at the network level. Our findings provide new mechanistic insights for optimizing this synergistic combination in patients. PMID: 33387481 [PubMed - as supplied by publisher]

Related Articles Stem cell-based models and therapies: a key approach into schizophrenia treatment. Cell Tissue Bank. 2021 Jan 02;: Authors: Larijani B, Parhizkar Roudsari P, Hadavandkhani M, Alavi-Moghadam S, Rezaei-Tavirani M, Goodarzi P, Sayahpour FA, Mohamadi-Jahani F, Arjmand B Abstract Psychiatric disorders such as schizophrenia can generate distress and disability along with heavy costs on individuals and health care systems. Different genetic and environmental factors play a pivotal role in the appearance of the mentioned disorders. Since the conventional treatment options for psychiatric disorders are suboptimal, investigators are trying to find novel strategies. Herein, stem cell therapies have been recommended as novel choices. In this context, the preclinical examination of stem cell-based therapies specifically using appropriate models can facilitate passing strong filters and serious examination to ensure proper quality and safety of them as a novel treatment approach. Animal models cannot be adequately helpful to follow pathophysiological features. Nowadays, stem cell-based models, particularly induced pluripotent stem cells reflected as suitable alternative models in this field. Accordingly, the importance of stem cell-based models, especially to experiment with the regenerative medicine outcomes for schizophrenia as one of the severe typing of psychiatric disorders, is addressed here. PMID: 33387152 [PubMed - as supplied by publisher]

Related Articles Salivary metabolomics for the diagnosis of periodontal diseases: a systematic review with methodological quality assessment. Metabolomics. 2021 Jan 01;17(1):1 Authors: Baima G, Iaderosa G, Citterio F, Grossi S, Romano F, Berta GN, Buduneli N, Aimetti M Abstract INTRODUCTION: Early diagnosis of periodontitis by means of a rapid, accurate and non-invasive method is highly desirable to reduce the individual and epidemiological burden of this largely prevalent disease. OBJECTIVES: The aims of the present systematic review were to examine potential salivary metabolic biomarkers and pathways associated to periodontitis, and to assess the accuracy of salivary untargeted metabolomics for the diagnosis of periodontal diseases. METHODS: Relevant studies identified from MEDLINE (PubMed), Embase and Scopus databases were systematically examined for analytical protocols, metabolic biomarkers and results from the multivariate analysis (MVA). Pathway analysis was performed using the MetaboAnalyst online software and quality assessment by means of a modified version of the QUADOMICS tool. RESULTS: Twelve studies met the inclusion criteria, with sample sizes ranging from 19 to 130 subjects. Compared to periodontally healthy individuals, valine, phenylalanine, isoleucine, tyrosine and butyrate were found upregulated in periodontitis patients in most studies; while lactate, pyruvate and N-acetyl groups were the most significantly expressed in healthy individuals. Metabolic pathways that resulted dysregulated are mainly implicated in inflammation, oxidative stress, immune activation and bacterial energetic metabolism. The findings from MVA revealed that periodontitis is characterized by a specific metabolic signature in saliva, with coefficients of determination ranging from 0.52 to 0.99. CONCLUSIONS: This systematic review summarizes candidate metabolic biomarkers and pathways related to periodontitis, which may provide opportunities for the validation of diagnostic or predictive models and the discovery of novel targets for monitoring and treating such a disease (PROSPERO CRD42020188482). PMID: 33387070 [PubMed - as supplied by publisher]

Related Articles Metabolomics approach based on LC-HRMS for the fast screening of iron(II)-chelating peptides in protein hydrolysates. Anal Bioanal Chem. 2021 Jan 02;: Authors: Paris C, Selmeczi K, Ebel B, Stefan L, Csire G, Cakir-Kiefer C, Desobry S, Canabady-Rochelle L, Chaimbault P Abstract Production of iron-chelating peptides from protein hydrolysates requires robust and adequate screening methods to optimize their purification and subsequently valorize their potential antioxidant properties. An original methodology was developed for direct and sensitive screening of iron(II)-chelating peptides based on ion-pair reverse phase liquid chromatography (IP-RPLC) coupled to high-resolution mass spectrometry (HRMS). Peptide mixture was first added to iron(II) solution to form iron(II)-peptide complexes. Then IP-RPLC-HRMS analysis was conducted on this iron-peptide mixture and on the iron-free peptide solution for comparative mass spectra analysis. This protocol, initially applied to a range of low molecular weight standard peptides, allowed detection of [(Peptide-H)+56FeII]+ complex ion for iron(II)-chelating peptides (GGH, EAH, DAH, βAH, DMH, DTH, DSH). GGH was added in complex peptide mixtures and targeted analysis of [(GGH-H)+56FeII]+ complex showed a limit of detection (LOD) below 0.77 mg L-1 of GGH. This protocol was finally tested in combination with metabolomics software and additional digital processing for non-targeted search for iron(II)-chelating peptides. Applicability of this new screening methodology has been validated by detection of GGH as iron(II)-chelating peptide when added at 0.77 mg L-1 in casein hydrolysate. Graphical abstract. PMID: 33386417 [PubMed - as supplied by publisher]

Related Articles Enteral Vitamin A for Reducing Severity of Bronchopulmonary Dysplasia: A Randomized Trial. Pediatrics. 2021 Jan;147(1): Authors: Rakshasbhuvankar AA, Simmer K, Patole SK, Stoecklin B, Nathan EA, Clarke MW, Pillow JJ Abstract BACKGROUND AND OBJECTIVES: Evidence suggests that intramuscular vitamin A reduces the risk of bronchopulmonary dysplasia (BPD) in preterm infants. Our objective was to compare enteral water-soluble vitamin A with placebo supplementation to reduce the severity of BPD in extremely preterm infants. METHODS: We conducted a double-blind randomized controlled trial in infants <28 weeks' gestation who were to receive either enteral water-soluble vitamin A (5000 IU per day) or a placebo. Supplementation was started within 24 hours of introduction of feeds and continued until 34 weeks' postmenstrual age (PMA). The primary outcome was the severity of BPD, assessed by using the right shift of the pulse oximeter saturation versus the inspired oxygen pressure curve. RESULTS: A total of 188 infants were randomly assigned. The mean ± SD birth weight (852 ± 201 vs 852 ± 211 g) and gestation (25.8 ± 1.49 vs 26.0 ± 1.39 weeks) were comparable between the vitamin A and placebo groups. There was no difference in the right shift (median [25th-75th percentiles]) of the pulse oximeter saturation versus inspired oxygen pressure curve (in kilopascals) between the vitamin A (11.1 [9.5-13.7]) and placebo groups (10.7 [9.5-13.1]) (P = .73). Enteral vitamin A did not affect diagnosis of BPD or other clinical outcomes. Plasma retinol levels were significantly higher in the vitamin A group versus the placebo group on day 28 and at 34 weeks' PMA. CONCLUSIONS: Enteral water-soluble vitamin A supplementation improves plasma retinol levels in extremely preterm infants but does not reduce the severity of BPD. PMID: 33386338 [PubMed - as supplied by publisher]

Related Articles Soil assessment after chemical accidents using metabolic profiling and microbial community evaluation. Chemosphere. 2020 Dec 18;268:129362 Authors: Kim N, Ahn Y, Jo J, Pyo H, Lee J, Choi J Abstract This study investigated the effects of accidental contamination of soils with phenol, toluene, nitric acid, and hydrogen fluoride (HF) by simulating chemical leakage in the soil with/without rain and characterizing the resulting metabolites and microbial. In the case of acid leakage, pH and cation exchange capacity were decreased, and the content of fluoride ion was increased in case of HF leakage. Using mass spectrometry-based metabolomics analysis, phytosphingosine was detected as a distinguishing metabolite in soils contaminated with phenol and HF in rain conditions. Microbial communities were identified by 16s rRNA metagenome sequencing. Sphingomonas was one of the dominant species in soils contaminated with phenol and HF. These results suggest that phytosphingosine and Sphingomonas might be used as biomarkers to evaluate the status of soils contaminated with phenol or HF. Under simulated rain conditions, the species alpha-diversity index of soil microbes and the physicochemical properties of the soil indicated values close to those of the uncontaminated soil. Rain played an important role in the recovery of microbial and metabolic profiles after chemical accidents. Metabolic profiling and microbial community analysis can serve as a diagnostic tool for ecotoxicological research at chemical accident sites. PMID: 33385834 [PubMed - as supplied by publisher]

Related Articles Combination of UHPLC-MS/MS-molecular networking approach and FTICR-MS for the metabolic profiling of Saccharomyces cerevisiae. J Pharm Biomed Anal. 2020 Dec 19;195:113857 Authors: Perruchon O, Schmitz-Afonso I, Grondin C, Casaregola S, Afonso C, Elomri A Abstract Natural products are a reliable source of bioactive molecules and represent an industrial and pharmaceutical stake. Indeed, the model yeast species Saccharomyces cerevisiae is a well-known eukaryotic organism largely used as a biotechnological tool, but still a topical subject of study. In this work, the exploration of Saccharomyces cerevisiae is taken further through an untargeted metabolomics workflow. The aim is to enrich databases and bring new information about the standard S. cerevisiae strain in a given medium. Analytical methods and bioinformatics tools were combined in a high-throughput methodology useable to dereplicate many types of biological extracts and cartography secondary metabolites. Ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analyses were carried out and spectral data were pre-processed to build molecular networks. Annotations were attributed to compounds through comparison with databases and manual investigation of networks. Ultra-high-resolution Fourier-transform ion cyclotron resonance mass spectrometry (FTICR-MS) brought additional information thanks to a higher dynamic range and enhanced UHPLC-MS/MS results by unveiling ambiguities and bringing accurate molecular formulae. Therefore, accurate and reliable annotated features resulted from the UHPLC-MS/MS data while FTICR-MS provided an overall cartography of metabolites thanks to van Krevelen diagrams. Various small molecules such as amino acids derivatives and indole alkaloids have been determined for the first time in this yeast. The complementarity of FTICR-MS and UHPLC-MS/MS for secondary metabolite annotation brought this new mapping of S. cerevisiae. PMID: 33385718 [PubMed - as supplied by publisher]

Related Articles SkinBug: an artificial intelligence approach to predict human skin microbiome-mediated metabolism of biotics and xenobiotics. iScience. 2021 Jan 22;24(1):101925 Authors: Jaiswal SK, Agarwal SM, Thodum P, Sharma VK Abstract In addition to being pivotal for the host health, the skin microbiome possesses a large reservoir of metabolic enzymes, which can metabolize molecules (cosmetics, medicines, pollutants, etc.) that form a major part of the skin exposome. Therefore, to predict the complete metabolism of any molecule by skin microbiome, a curated database of metabolic enzymes (1,094,153), reactions, and substrates from ∼900 bacterial species from 19 different skin sites were used to develop "SkinBug." It integrates machine learning, neural networks, and chemoinformatics methods, and displays a multiclass multilabel accuracy of up to 82.4% and binary accuracy of up to 90.0%. SkinBug predicts all possible metabolic reactions and associated enzymes, reaction centers, skin microbiome species harboring the enzyme, and the respective skin sites. Thus, SkinBug will be an indispensable tool to predict xenobiotic/biotic metabolism by skin microbiome and will find applications in exposome and microbiome studies, dermatology, and skin cancer research. PMID: 33385118 [PubMed]

Related Articles Metabolite Fingerprinting of Kersting's Groundnut [Macrotyloma geocarpum (Harms) Maréchal & Baudet] Seeds Using UPLC-qTOF-MS Reveals the Nutraceutical and Antioxidant Potentials of the Orphan Legume. Front Nutr. 2020;7:593436 Authors: Tsamo AT, Mohammed M, Dakora FD Abstract The identification and subsequent quantification of phenolic compounds in plants is the first step toward harnessing their associated nutritional and health benefits. Due to their diverse phenolic compound compositions, grain legumes are known for their high nutritional and health values. The aim of this study was to assess the inter-variations in chemical composition, phytochemical content, and antioxidant capacity of seed extracts from eight Kersting's groundnut [Macrotyloma geocarpum (Harms) Marechal & Baudet] landraces. The chemical profiles were evaluated using UPLC-qTOF-MS. Total phenolics and flavonoids content were determined by the Folin-Ciocalteu and aluminum chloride methods, respectively. The antioxidant capacities in the forms of DPPH and ABTS were evaluated using spectrophotometric methods. Principal component analysis was used to define similarities/differences between the landraces. Based on untargeted metabolomics analysis, 57 metabolites were identified, with phenolics, triterpenes, fatty acids, and sphingolipids being the most predominant. The results showed that the black seeded KG1 (Puffeun) had the highest total phenolic (9.44 mg GAE/g) and flavonoid (3.01 mg QE/g) contents, as well as antioxidant capacity (9.17 μg/mL and 18.44 μg/mL based on DDPH and ABTS assays, respectively). The concentrations of ferulic acid hexoside, procyanidin B2, eryodictyiol-7-rutinoside and quercetin pentoside ranged from 51.78-441.31, 1.86-18.25, 3.26-13.95 to 5.44-63.85 μg/mg, respectively. This study presents a useful report on the phytochemical characterization of Kersting's groundnuts and shows that the grains can be used as a source of nutraceuticals for human consumption. PMID: 33385005 [PubMed]

Related Articles The Implications of PDK1-4 on Tumor Energy Metabolism, Aggressiveness and Therapy Resistance. Front Oncol. 2020;10:583217 Authors: Atas E, Oberhuber M, Kenner L Abstract A metabolic shift from oxidative phosphorylation (OXPHOS) to glycolysis-known as the Warburg effect-is characteristic for many cancers. It gives the cancer cells a survival advantage in the hypoxic tumor microenvironment and protects them from cytotoxic effects of oxidative damage and apoptosis. The main regulators of this metabolic shift are the pyruvate dehydrogenase complex and pyruvate dehydrogenase kinase (PDK) isoforms 1-4. PDK is known to be overexpressed in several cancers and is associated with bad prognosis and therapy resistance. Whereas the expression of PDK1-3 is tissue specific, PDK4 expression is dependent on the energetic state of the whole organism. In contrast to other PDK isoforms, not only oncogenic, but also tumor suppressive functions of PDK4 have been reported. In tumors that profit from high OXPHOS and high de novo fatty acid synthesis, PDK4 can have a protective effect. This is the case for prostate cancer, the most common cancer in men, and makes PDK4 an interesting therapeutic target. While most work is focused on PDK in tumors characterized by high glycolytic activity, little research is devoted to those cases where PDK4 acts protective and is therefore highly needed. PMID: 33384955 [PubMed]