Integrative Molecular Phenotyping
INTEGRATIVE MOLECULAR
PHENOTYPING
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY

PubMed

Metabolomics

Tue, 08/11/2022 - 12:00
Nat Biotechnol. 2022 Nov 8. doi: 10.1038/s41587-022-01553-2. Online ahead of print.NO ABSTRACTPMID:36347976 | DOI:10.1038/s41587-022-01553-2

Extensive metabolic consequences of human glycosyltransferase gene knockouts in prostate cancer

Tue, 08/11/2022 - 12:00
Br J Cancer. 2022 Nov 8. doi: 10.1038/s41416-022-02040-w. Online ahead of print.ABSTRACTBACKGROUND: Naturally occurring germline gene deletions (KO) represent a unique setting to interrogate gene functions. Complete deletions and differential expression of the human glycosyltransferase UGT2B17 and UGT2B28 genes are linked to prostate cancer (PCa) risk and progression, leukaemia, autoimmune and other diseases.METHODS: The systemic metabolic consequences of UGT deficiencies were examined using untargeted and targeted mass spectrometry-based metabolomics profiling of carefully matched, treatment-naive PCa cases.RESULTS: Each UGT KO differentially affected over 5% of the 1545 measured metabolites, with divergent metabolic perturbations influencing the same pathways. Several of the perturbed metabolites are known to promote PCa growth, invasion and metastasis, including steroids, ceramides and kynurenine. In UGT2B17 KO, reduced levels of inactive steroid-glucuronides were compensated by sulfated derivatives that constitute circulating steroid reservoirs. UGT2B28 KO presented remarkably lower levels of oxylipins paralleled by reduced inflammatory mediators, but higher ceramides unveiled as substrates of the enzyme in PCa cells.CONCLUSION: The distinctive and broad metabolic rewiring caused by UGT KO reinforces the need to examine their unique and divergent functions in PCa biology.PMID:36347965 | DOI:10.1038/s41416-022-02040-w

Molecular Networking and On-Tissue Chemical Derivatization for Enhanced Identification and Visualization of Steroid Glycosides by MALDI Mass Spectrometry Imaging

Tue, 08/11/2022 - 12:00
Anal Chem. 2022 Nov 8. doi: 10.1021/acs.analchem.2c02694. Online ahead of print.ABSTRACTSpatial metabolomics describes the spatially resolved analysis of interconnected pathways, biochemical reactions, and transport processes of small molecules in the spatial context of tissues and cells. However, a broad range of metabolite classes (e.g., steroids) show low intrinsic ionization efficiencies in mass spectrometry imaging (MSI) experiments, thus restricting the spatial characterization of metabolic networks. Additionally, decomposing complex metabolite networks into chemical compound classes and molecular annotations remains a major bottleneck due to the absence of repository-scaled databases. Here, we describe a multimodal mass-spectrometry-based method combining computational metabolome mining tools and high-resolution on-tissue chemical derivatization (OTCD) MSI for the spatially resolved analysis of metabolic networks at the low micrometer scale. Applied to plant toxin sequestration in Danaus plexippus as a model system, we first utilized liquid chromatography (LC)-MS-based molecular networking in combination with artificial intelligence (AI)-driven chemical characterization to facilitate the structural elucidation and molecular identification of 32 different steroidal glycosides for the host-plant Asclepias curassavica. These comprehensive metabolite annotations guided the subsequent matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) analysis of cardiac-glycoside sequestration in D. plexippus. We developed a spatial-context-preserving OTCD protocol, which improved cardiac glycoside ion yields by at least 1 order of magnitude compared to results with untreated samples. To illustrate the potential of this method, we visualized previously inaccessible (sub)cellular distributions (2 and 5 μm pixel size) of steroidal glycosides in D. plexippus, thereby providing a novel insight into the sequestration of toxic metabolites and guiding future metabolomics research of other complex sample systems.PMID:36347515 | DOI:10.1021/acs.analchem.2c02694

Plasma metabolic signatures for intracranial aneurysm and its rupture identified by pseudotargeted metabolomics

Tue, 08/11/2022 - 12:00
Clin Chim Acta. 2022 Nov 5:S0009-8981(22)01360-2. doi: 10.1016/j.cca.2022.11.002. Online ahead of print.ABSTRACTBACKGROUND AND AIMS: The vital metabolic signatures for IA risk stratification and its potential biological underpinnings remain elusive. Our study aimed to develop an early diagnosis model and rupture classification model by analyzing plasma metabolic profiles of IA patients.MATERIALS AND METHODS: Plasma samples from a cohort of 105 participants, including 75 IA patients in unruptured and ruptured status (UIA, RIA) and 30 control participants were collected for comprehensive metabolic evaluation using ultra-high-performance liquid chromatography-mass spectrometry-based pseudotargeted metabolomics method. Furthermore, an integrated machine learning strategy based on LASSO, random forest and logistic regression were used for feature selection and model construction.RESULTS: The metabolic profiling disturbed significantly in UIA and RIA patients. Notably, adenosine content was significantly downregulated in UIA, and various glycine-conjugated secondary bile acids were decreased in RIA patients. Enriched KEGG pathways included glutathione metabolism and bile acid metabolism. Two sets of biomarker panels were defined to discriminate IA and its rupture with the area under receiver operating characteristic curve of 0.843 and 0.929 on the validation sets, respectively.CONCLUSIONS: The present study could contribute to a better understanding of IA etiopathogenesis and facilitate discovery of new therapeutic targets. The metabolite panels may serve as potential non-invasive diagnostic and risk stratification tool for IA.PMID:36347333 | DOI:10.1016/j.cca.2022.11.002

Integration of metabolomics and proteomics analysis to explore the mechanism of neurotoxicity induced by receipt of isoniazid and rifampicin in mice

Tue, 08/11/2022 - 12:00
Neurotoxicology. 2022 Nov 5:S0161-813X(22)00177-2. doi: 10.1016/j.neuro.2022.11.004. Online ahead of print.ABSTRACTIsoniazid (INH) and rifampicin (RIF) are co-administered in tuberculosis treatment but can cause neurotoxicity, and the mechanism is not known. To explore this mechanism, we employed an integrated approach using metabolomics analysis (MA) and proteomics analysis (PA). Male mice were divided into three groups and administered vehicle (control group), or co-administered INH (120mg/kg) and RIF (240mg/kg), for 7 or 14 days. Mice brains were collected for mass spectrometry-based PA and MA plus lipidomics analysis. Measurement of brain levels of malondialdehyde and superoxide dismutase revealed time-dependent brain injury after exposure to INH+RIF for 7 and 14 days. Also, 422 proteins, 35 metabolites, and 21 lipids were dysregulated and identified. MA demonstrated "purine metabolism," "phenylalanine, tyrosine and tryptophan biosynthesis," "biosynthesis of unsaturated fatty acids," "phenylalanine metabolism," and "arginine biosynthesis" to be disturbed significantly. PA demonstrated pathways such as "lipids," "amino acids," and "energy metabolism" to be disrupted. Peroxisome proliferator-activated receptor (PPAR) pathways were changed in energy metabolism, which led to the neurotoxicity induced by INH+RIF. Immunohistochemical analyses of PPARs in mice brains verified that PPAR-α and -γ expression was downregulated. PPAR-α and -γ activation might be a key target for alleviating INH+RIF-induced neurotoxicity.PMID:36347327 | DOI:10.1016/j.neuro.2022.11.004

Jingfang Granules improve glucose metabolism disturbance and inflammation in mice with urticaria by up-regulating LKB1/AMPK/SIRT1 axis

Tue, 08/11/2022 - 12:00
J Ethnopharmacol. 2022 Nov 5:115913. doi: 10.1016/j.jep.2022.115913. Online ahead of print.ABSTRACTETHNOPHARMACOLOGICAL RELEVANCE: Jingfang Granule (JFG) is a classical traditional Chinese medicine prescription to empirically treat skin disease such as urticaria in clinical practice. However, the potential mechanisms of JFG on urticaria are not fully defined.AIM OF STUDY: The aim of this study is to investigate the mechanisms of JFG in treating urticaria through an OVA/aluminum hydroxide induced urticaria mice model.MATERIALS AND METHODS: KM mice were injected intraperitoneally (i.p.) with OVA/aluminium hydroxide to establish the model with urticaria. After the mice were administered JFG, itching degree and hematoxylin and eosin (H&E) staining were used to assess the protective effect of JFG on mice with urticaria. The regulatory networks were investigated by proteomics and central carbon metabolomics. Spleen T lymphocyte subsets were detected by flow cytometry. Peripheral blood cytokines were detected using ELISA kits or Cytometric Bead Array (CBA) kits. The protein expression of skin tissue was detected by western blot or immunohistochemical staining.RESULTS: JFG significantly relived skin tissue lesions and skin pruritus in mice with urticaria. Meanwhile, JFG significantly decreased IgE, IL-1β, IL-6, IL-4, TNF-α and IL-17A levels and increased IFN-γ levels in the serum of urticaria mice by inhibiting the expression of inflammation associated proteins including TLR4 and p-NF-κB p65, p-ERK1/2, p-JNK and p-p38, NLRP3, ASC and cleaved caspase-1. The results of proteomics, central carbon metabolomics, western blot and Immunohistochemical staining confirmed that JFG inhibited Glycolysis/Gluconeogenesis and Pentose phosphate pathway in the skin tissue of urticaria mice by activating the LKB1/AMPK/SIRT1 axis and then downregulating the protein expressions of Glut1, TORC2, p-CREB, PEPCK, HNF4α and G6Pase.CONCLUSION: The current study demonstrates that JFG is effective in treating OVA/aluminum hydroxide-induced skin lesions and inflammation in mice, and JFG exhibits the clinical benefits via modulating LKB1/AMPK/SIRT1 axis, which in turn inhibits Glycolysis/Gluconeogenesis and Pentose phosphate pathway.PMID:36347302 | DOI:10.1016/j.jep.2022.115913

The follicular fluid metabolome in infertile individuals between polycystic ovary syndrome and diminished ovarian reserve

Tue, 08/11/2022 - 12:00
Arch Biochem Biophys. 2022 Nov 5:109453. doi: 10.1016/j.abb.2022.109453. Online ahead of print.ABSTRACTFollicular fluid is the microenvironment of oocytes that plays a crucial role in oocyte development. This study intended to explore the follicular fluid metabolomics in diminished ovarian reserve (DOR), polycystic ovarian syndrome (PCOS), and normal ovary response (NOR) groups. For metabolomic analysis, we collected the follicular fluid samples from 28 patients with DOR, 28 patients with NOR, and 28 patients with PCOS. The identified metabolites were annotated using KEGG to determine the metabolic pathway disturbances in PCOS and DOR. Based on the regression model, we conducted ROC analysis to identify PCOS and DOR biomarkers in the follicular fluid. The present results identified that the DOR and NOR groups' differential metabolites were primarily enriched in the choline pathway. The concentrations of pregnanediol-3-glucuronide and 2-hydroxyestrone sulfate in the ODR and NOR groups were substantially different. The metabolites in the purine metabolism pathway were mainly enriched in the PCOS and NOR groups. N-Acetyl-S-(N-methylcarbamoyl) cysteine and 3,4-dehydrothiomorpholine in the ODR and NOR groups were substantially different. We also identified metabolic alterations in PCOS and DOR follicular fluid, which provides novel ways for PCOS and DOR diagnosis and therapy.PMID:36347279 | DOI:10.1016/j.abb.2022.109453

A microbial transporter of the dietary antioxidant ergothioneine

Tue, 08/11/2022 - 12:00
Cell. 2022 Nov 3:S0092-8674(22)01323-X. doi: 10.1016/j.cell.2022.10.008. Online ahead of print.ABSTRACTLow-molecular-weight (LMW) thiols are small-molecule antioxidants required for the maintenance of intracellular redox homeostasis. However, many host-associated microbes, including the gastric pathogen Helicobacter pylori, unexpectedly lack LMW-thiol biosynthetic pathways. Using reactivity-guided metabolomics, we identified the unusual LMW thiol ergothioneine (EGT) in H. pylori. Dietary EGT accumulates to millimolar levels in human tissues and has been broadly implicated in mitigating disease risk. Although certain microorganisms synthesize EGT, we discovered that H. pylori acquires this LMW thiol from the host environment using a highly selective ATP-binding cassette transporter-EgtUV. EgtUV confers a competitive colonization advantage in vivo and is widely conserved in gastrointestinal microbes. Furthermore, we found that human fecal bacteria metabolize EGT, which may contribute to production of the disease-associated metabolite trimethylamine N-oxide. Collectively, our findings illustrate a previously unappreciated mechanism of microbial redox regulation in the gut and suggest that inter-kingdom competition for dietary EGT may broadly impact human health.PMID:36347253 | DOI:10.1016/j.cell.2022.10.008

Recent progress in mass spectrometry for single-cell metabolomics

Tue, 08/11/2022 - 12:00
Curr Opin Chem Biol. 2022 Nov 5;71:102226. doi: 10.1016/j.cbpa.2022.102226. Online ahead of print.ABSTRACTMetabolites are the end products of cellular vital activities and can reflect the state of cellular to a certain extent. Rapid change of metabolites and the low abundance of signature metabolites cause difficulties in single-cell detection, which is a great challenge in single-cell metabolomics analysis. Mass spectrometry (MS) is a powerful tool that uniquely suited to detect intracellular small-molecule metabolites and has shown good application in single-cell metabolite analysis. In this mini-review, we describe three types of emerging technologies for MS-based single-cell metabolic analysis in recent years, including nano-ESI-MS based single-cell metabolomics analysis, high-throughput analysis via flow cytometry, and cellular metabolic imaging analysis. These techniques provide a large amount of single-cell metabolic data, allowing the potential of MS in single-cell metabolic analysis is gradually being explored and is of great importance in disease and life science research.PMID:36347197 | DOI:10.1016/j.cbpa.2022.102226

A liquid chromatography-mass spectroscopy-based untargeted metabolomic study of the rat cochlear nucleus at various stages of maturity

Tue, 08/11/2022 - 12:00
Hear Res. 2022 Nov 2;426:108645. doi: 10.1016/j.heares.2022.108645. Online ahead of print.ABSTRACTThe cochlear nucleus receives numerous inputs from auditory and nonauditory systems. This extensive innervation of the cochlear nucleus is involved in sound source localization and the integration of auditory signals with other sensory modalities. The dorsal cochlear nucleus may also have an important role in tinnitus. Although its gross anatomy and function have been extensively studied, the metabolome of the cochlear nucleus remains poorly understood, particularly at different stages of auditory maturity. Here, we present a protocol for untargeted metabolomics analysis of the rat cochlear nucleus, then discuss differences in the metabolome of the rat cochlear nucleus between postnatal day (PD) 14 (hearing onset) and PD60 (hearing maturation). Cochlear nucleus samples collected from rats at PD14 or PD60 were analyzed by liquid chromatography-tandem mass spectrometry (LCMS). In total, 344 metabolites were identified. Principal component analysis and orthogonal partial least-square discriminant analysis showed that the metabolic profiles at these two stages had distinct distribution patterns. Moreover, 91 significantly differential metabolites (62 upregulated and 29 downregulated) were identified at PD60 vs. PD14. N-acetylaspartylglutamic acid (NAAG), γ-aminobutyric acid (GABA), taurine, adenosine monophosphate (AMP), and choline were significantly upregulated at PD60. Pathway enrichment analysis suggested that alanine, aspartate, and glutamate metabolism; glycine, serine, and threonine metabolism; the mammalian target of rapamycin (mTOR) signaling pathway; and the AMP-activated protein kinase (AMPK) signaling pathway may be involved in key developmental events during maturation of the cochlear nucleus. Taken together, the metabolic profiles identified in this study could lead to the identification and understanding of specific key biomarkers and metabolic pathways involved in the maturation of hearing. Moreover, LC-MS-based metabolomics provides an alternative approach for the characterization of auditory maturation and auditory diseases.PMID:36347123 | DOI:10.1016/j.heares.2022.108645

Hypoxic storage of murine red blood cells improves energy metabolism and post-transfusion recoveries

Tue, 08/11/2022 - 12:00
Blood Transfus. 2022 Oct 21. doi: 10.2450/2022.0172-22. Online ahead of print.ABSTRACTBACKGROUND: The Red blood cell (RBC) storage lesion results in decreased circulation and function of transfused RBCs. Elevated oxidant stress and impaired energy metabolism are a hallmark of the storage lesion in both human and murine RBCs. Although human studies don't suffer concerns that findings may not translate, they do suffer from genetic and environmental variability amongst subjects. Murine models can control for genetics, environment, and much interventional experimentation can be carried out in mice that is neither technically feasible nor ethical in humans. However, murine models are only useful to the extent that they have similar biology to humans. Hypoxic storage has been shown to mitigate the storage lesion in human RBCs, but has not been investigated in mice.MATERIALS AND METHODS: RBCs from a C57BL6/J mouse strain were stored under normoxic (untreated) or hypoxic conditions (SO2 ~ 26%) for 1h, 7 and 12 days. Samples were tested for metabolomics at steady state, tracing experiments with 1,2,3-13C3-glucose, proteomics and end of storage post transfusion recovery.RESULTS: Hypoxic storage improved post-transfusion recovery and energy metabolism, including increased steady state and 13C3-labeled metabolites from glycolysis, high energy purines (adenosine triphosphate) and 2,3-diphospholgycerate. Hypoxic storage promoted glutaminolysis, increased glutathione pools, and was accompanied by elevation in the levels of free fatty acids and acyl-carnitines.DISCUSSION: This study isolates hypoxia, as a single independent variable, and shows similar effects as seen in human studies. These findings also demonstrate the translatability of murine models for hypoxic RBC storage and provide a pre-clinical platform for ongoing study.PMID:36346885 | DOI:10.2450/2022.0172-22

The highest-elevation frog provides insights into mechanisms and evolution of defenses against high UV radiation

Tue, 08/11/2022 - 12:00
Proc Natl Acad Sci U S A. 2022 Nov 15;119(46):e2212406119. doi: 10.1073/pnas.2212406119. Epub 2022 Nov 8.ABSTRACTDefense against ultraviolet (UV) radiation exposure is essential for survival, especially in high-elevation species. Although some specific genes involved in UV response have been reported, the full view of UV defense mechanisms remains largely unexplored. Herein, we used integrated approaches to analyze UV responses in the highest-elevation frog, Nanorana parkeri. We show less damage and more efficient antioxidant activity in skin of this frog than those of its lower-elevation relatives after UV exposure. We also reveal genes related to UV defense and a corresponding temporal expression pattern in N. parkeri. Genomic and metabolomic analysis along with large-scale transcriptomic profiling revealed a time-dependent coordinated defense mechanism in N. parkeri. We also identified several microRNAs that play important regulatory roles, especially in decreasing the expression levels of cell cycle genes. Moreover, multiple defense genes (i.e., TYR for melanogenesis) exhibit positive selection with function-enhancing substitutions. Thus, both expression shifts and gene mutations contribute to UV adaptation in N. parkeri. Our work demonstrates a genetic framework for evolution of UV defense in a natural environment.PMID:36346846 | DOI:10.1073/pnas.2212406119

Metabolite activation of tumorigenic signaling pathways in the tumor microenvironment

Tue, 08/11/2022 - 12:00
Sci Signal. 2022 Nov 8;15(759):eabj4220. doi: 10.1126/scisignal.abj4220. Epub 2022 Nov 8.ABSTRACTThe role of metabolites exchanged in the tumor microenvironment is largely thought of as fuels to drive the increased biosynthetic and bioenergetic demands of growing tumors. However, this view is shifting as metabolites are increasingly shown to function as signaling molecules that directly regulate oncogenic pathways. Combined with our growing understanding of the essential role of stromal cells, this shift has led to increased interest in how the collective and interconnected metabolome of the tumor microenvironment can drive malignant transformation, epithelial-to-mesenchymal transition, drug resistance, immune evasion, and metastasis. In this review, we discuss how metabolite exchange between tumors and various cell types in the tumor microenvironment-such as fibroblasts, adipocytes, and immune cells-can activate signaling pathways that drive cancer progression.PMID:36346837 | DOI:10.1126/scisignal.abj4220

Watermelon domestication was shaped by stepwise selection and regulation of the metabolome

Tue, 08/11/2022 - 12:00
Sci China Life Sci. 2022 Nov 4. doi: 10.1007/s11427-022-2198-5. Online ahead of print.ABSTRACTAlthough crop domestication has greatly aided human civilization, the sequential domestication and regulation of most quality traits remain poorly understood. Here, we report the stepwise selection and regulation of major fruit quality traits that occurred during watermelon evolution. The levels of fruit cucurbitacins and flavonoids were negatively selected during speciation, whereas sugar and carotenoid contents were positively selected during domestication. Interestingly, fruit malic acid and citric acid showed the opposite selection trends during the improvement. We identified a novel gene cluster (CGC1, cucurbitacin gene cluster on chromosome 1) containing both regulatory and structural genes involved in cucurbitacin biosynthesis, which revealed a cascade of transcriptional regulation operating mechanisms. In the CGC1, an allele caused a single nucleotide change in ClERF1 binding sites (GCC-box) in the promoter of ClBh1, which resulted in reduced expression of ClBh1 and inhibition of cucurbitacin synthesis in cultivated watermelon. Functional analysis revealed that a rare insertion of 244 amino acids, which arose in C. amarus and became fixed in sweet watermelon, in ClOSC (oxidosqualene cyclase) was critical for the negative selection of cucurbitacins during watermelon evolution. This research provides an important resource for metabolomics-assisted breeding in watermelon and for exploring metabolic pathway regulation mechanisms.PMID:36346547 | DOI:10.1007/s11427-022-2198-5

Plasma metabolomic profiles reveal sex- and maturation-dependent metabolic strategies in sea lamprey (Petromyzon marinus)

Tue, 08/11/2022 - 12:00
Metabolomics. 2022 Nov 8;18(11):90. doi: 10.1007/s11306-022-01951-2.ABSTRACTINTRODUCTION: Adult sea lamprey (Petromyzon marinus) cease feeding and migrate to spawning streams where males build nests, undergo final sexual maturation, and subsequently produce and release large quantities of bile acid pheromones that attract mature females. These animals are predicted to rearrange their metabolic pathways drastically to support their reproductive strategies, presenting advantageous opportunities to examine how sex and the maturation processes affect metabolism.OBJECTIVES: The objective is to investigate the metabolic differences between sexes and maturation states in sea lamprey that support changes in physiological functions.METHODS: We compared plasma metabolomes of spawning and prespawning sea lamprey in both sexes using both non-targeted and targeted metabolomics approaches using UPLC/MS-MS with electrospray ionization in both positive and negative modes. The data were processed using Progenesis QI, Compound Discoverer and XCMS softwares for alignment, peak picking, and deconvolution of the peaks. Principle component analyses (PCA) and partial least squares discriminant analyses (PLS-DA) were performed using SIMCA and Metaboanalyst softwares to identify discriminating features, followed by fragmentation matching with extensive database search and pathway mapping.RESULTS: The pheromonal bile acid biosynthesis was upregulated significantly in males compared to females. Spermiating males further upregulated bile acid biosynthesis by altering amino acid metabolisms, upregulating cofactors and nucleotide metabolisms, but downregulating carbohydrate and energy metabolisms.CONCLUSION: Plasma metabolomes are sex- and maturation-dependent and reflect the special metabolic demands at each life stage and reproductive strategy.PMID:36346466 | DOI:10.1007/s11306-022-01951-2

Understanding the Link between Sleep and Health using Metabolomics

Tue, 08/11/2022 - 12:00
Sleep. 2022 Nov 8:zsac268. doi: 10.1093/sleep/zsac268. Online ahead of print.NO ABSTRACTPMID:36346440 | DOI:10.1093/sleep/zsac268

Machine Learning Analysis of the Cerebrovascular Thrombi Lipidome in Acute Ischemic Stroke

Tue, 08/11/2022 - 12:00
J Neurosci Nurs. 2022 Nov 8. doi: 10.1097/JNN.0000000000000682. Online ahead of print.ABSTRACTOBJECTIVE: The aim of this study was to identify a signature lipid profile from cerebral thrombi in acute ischemic stroke (AIS) patients at the time of ictus. METHODS: We performed untargeted lipidomics analysis using liquid chromatography-mass spectrometry on cerebral thrombi taken from a nonprobability, convenience sampling of adult subjects (≥18 years old, n = 5) who underwent thrombectomy for acute cerebrovascular occlusion. The data were classified using random forest, a machine learning algorithm. RESULTS: The top 10 metabolites identified from the random forest analysis were of the glycerophospholipid species and fatty acids. CONCLUSION: Preliminary analysis demonstrates feasibility of identification of lipid metabolomic profiling in cerebral thrombi retrieved from AIS patients. Recent advances in omic methodologies enable lipidomic profiling, which may provide insight into the cellular metabolic pathophysiology caused by AIS. Understanding of lipidomic changes in AIS may illuminate specific metabolite and lipid pathways involved and further the potential to develop personalized preventive strategies.PMID:36346351 | DOI:10.1097/JNN.0000000000000682

Validation of a New Salt-Assisted HS-GC-FID Method for the Determination of Ethanol in Vitreous Humor

Tue, 08/11/2022 - 12:00
J Anal Toxicol. 2022 Nov 8:bkac087. doi: 10.1093/jat/bkac087. Online ahead of print.ABSTRACTHeadspace gas chromatography with a flame ionization detector (HS-GC-FID) is a well-established approach for determining blood alcohol concentration (BAC), including in cadaveric specimens. Although the integrity of blood specimens can be adequately guaranteed after the sampling, the quantification of ethanol in cadaveric blood can be affected by postmortem fermentative phenomena occurring between the time since death and the sampling of biofluids. Vitreous humor is less affected by putrefactive phenomena allowing compound determination and its use as an alternative biological matrix. The present work aimed to develop and validate a method using the salting-out effect and based on HS-GC-FID for the ethanol determination in vitreous humor. The reported analytical method is based on a simple VH pre-treatment consisting of a dilution (1:9) with a solution of 2.5 mol/L K2CO3 and 0.0012 mol/L tert-butanol (internal standard). After 1 minute of incubation, part of the specimen evaporated in the headspace (2000 µL) is injected into the chromatographic system and analyzed in isothermal mode (40°C), with a chromatographic time of 1.6 minutes. The method was validated in terms of selectivity, lowest limit of detection, intraday and total imprecision, and trueness (bias). The determination of ethanol in vitreous humor and blood was carried out in 75 cases. The correlation between the two matrices was confirmed in 61 cases. However, 14 vitreous humor specimens showed lower ethanol concentrations, and in the related blood specimens, it was possible to identify the signal of n-propanol, a typical product of postmortem microbial fermentation, that justifies the excess of ethanol in the blood specimens.PMID:36346343 | DOI:10.1093/jat/bkac087

Glutathione and neodiosmin feedback sustain plant immunity

Tue, 08/11/2022 - 12:00
J Exp Bot. 2022 Nov 8:erac442. doi: 10.1093/jxb/erac442. Online ahead of print.ABSTRACTPlants have evolved a two-layer immune system comprising pattern-triggered immunity (PTI) and effector-triggered immunity (ETI) that is activated in response to pathogen invasion. Microbial patterns and pathogen effectors can be recognized by surface-localized pattern-recognition receptors (PRRs) and intracellularly localized nucleotide-binding leucine-rich repeat receptors (NLRs) to trigger PTI and ETI responses, respectively. At present, the metabolites activated by PTI and ETI and their roles and signaling pathways in plant immunity are not well understood. In this study, metabolomic analysis showed that ETI and PTI induced various flavonoids and amino acids and their derivatives to accumulate in plants. Interestingly, the contents of glutathione and neodiosmin were specifically upregulated by ETI and PTI, respectively, which significantly enhanced plant immunity. Further studies showed that glutathione and neodiosmin failed to induce a plant immune response in which PRRs/coreceptors were mutated. In addition, glutathione-reduced mutant gsh1 analysis showed that GSH1 is also required for PTI and ETI. Finally, we propose a possible model in which glutathione and neodiosmin are considered signature metabolites induced in the process of ETI and PTI activation in plants and further continuous enhancement of plant immunity in which PRRs/coreceptors are needed. This model is beneficial for the in-depth understanding of the closed-loop mode of the positive feedback regulation of PTI and ETI signals at the metabolic level.PMID:36346205 | DOI:10.1093/jxb/erac442

The Effect of Night Shifts on 24-h Rhythms in the Urinary Metabolome of Police Officers on a Rotating Work Schedule

Tue, 08/11/2022 - 12:00
J Biol Rhythms. 2022 Nov 8:7487304221132088. doi: 10.1177/07487304221132088. Online ahead of print.ABSTRACTShift workers face an increased risk of metabolic health problems, but the direct metabolic response to working nights is not fully understood. The aim of this study was to investigate the effect of night shifts on the 24-h urinary metabolome of shift workers. Eleven police officers working rotating shifts completed two 24-h laboratory visits that took place before and after they worked 7 consecutive nights. Sleep and meals were scheduled on a day schedule in the first visit and then on a night schedule (i.e., sleep and meals shifted by approximately 12 h) in the second visit. Targeted metabolomic analysis was performed on urine samples collected throughout these laboratory visits. Differential rhythmicity analysis was used to compare 24-h rhythms in urinary metabolites in both conditions. Our results show that on the day schedule, 24-h rhythms are present in the urinary levels of the majority of metabolites, but that this is significantly reduced on the night schedule, partly due to loss of organic acid rhythmicity. Furthermore, misalignment of 24-h metabolite rhythms with the shifted behavioral cycles in the night schedule was observed in more than half of the metabolites that were rhythmic in both conditions (all acylcarnitines). These results show that working nights alters the daily rhythms of the urinary metabolome in rotating shift workers, with the most notable impact observed for acylcarnitines and organic acids, 2 metabolite classes involved in mitochondrial function. Further research is warranted to study how these changes relate to the increased metabolic risks associated with shift work.PMID:36346168 | DOI:10.1177/07487304221132088

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