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

DeepION: A Deep Learning-Based Low-Dimensional Representation Model of Ion Images for Mass Spectrometry Imaging

Tue, 20/02/2024 - 12:00
Anal Chem. 2024 Feb 20. doi: 10.1021/acs.analchem.3c05002. Online ahead of print.ABSTRACTMass spectrometry imaging (MSI) is a high-throughput imaging technique capable of the qualitative and quantitative in situ detection of thousands of ions in biological samples. Ion image representation is a technique that produces a low-dimensional vector embedded with significant spectral and spatial information on an ion image, which further facilitates the distance-based similarity measurement for the identification of colocalized ions. However, given the low signal-to-noise ratios inherent in MSI data coupled with the scarcity of annotated data sets, achieving an effective ion image representation for each ion image remains a challenge. In this study, we propose DeepION, a novel deep learning-based method designed specifically for ion image representation, which is applied to the identification of colocalized ions and isotope ions. In DeepION, contrastive learning is introduced to ensure that the model can generate the ion image representation in a self-supervised manner without manual annotation. Since data augmentation is a crucial step in contrastive learning, a unique data augmentation strategy is designed by considering the characteristics of MSI data, such as the Poisson distribution of ion abundance and a random pattern of missing values, to generate plentiful ion image pairs for DeepION model training. Experimental results of rat brain tissue MSI show that DeepION outperforms other methods for both colocalized ion and isotope ion identification, demonstrating the effectiveness of ion image representation. The proposed model could serve as a crucial tool in the biomarker discovery and drug development of the MSI technique.PMID:38377545 | DOI:10.1021/acs.analchem.3c05002

Increased α-ketoglutarate links the C3-C4 intermediate state to C4 photosynthesis in the genus Flaveria

Tue, 20/02/2024 - 12:00
Plant Physiol. 2024 Feb 20:kiae077. doi: 10.1093/plphys/kiae077. Online ahead of print.ABSTRACTAs a complex trait, C4 photosynthesis has multiple independent origins in evolution. Phylogenetic evidence and theoretical analysis suggest that C2 photosynthesis, which is driven by glycine decarboxylation in the bundle sheath cell, may function as a bridge from C3 towards C4 photosynthesis. However, the exact molecular mechanism underlying the transition between C2 photosynthesis towards C4 photosynthesis remains elusive. Here, we provide evidence suggesting a role of higher α-ketoglutarate (AKG) concentration during this transition. Metabolomic data of 12 Flaveria species, including multiple photosynthetic types, show that AKG concentration initially increased in the C3-C4 intermediate with a further increase in C4 species. Petiole feeding of AKG increases the concentrations of C4 related metabolites in C3-C4 and C4 species but not the activity of C4 related enzymes. Sequence analysis shows that glutamate synthase (Fd-GOGAT), which catalyzes the generation of glutamate using AKG, was under strong positive selection during the evolution of C4 photosynthesis. Simulations with a constraint-based model for C3-C4 intermediate further show that decreasing the activity of Fd-GOGAT facilitated the transition from a C2-dominant to a C4-dominant CO2 concentrating mechanism. All these results provide insight into the mechanistic switch from C3-C4 intermediate to C4 photosynthesis.PMID:38377473 | DOI:10.1093/plphys/kiae077

Double blocking of carbon metabolism causes a large increase of Calvin-Benson cycle compounds in cyanobacteria

Tue, 20/02/2024 - 12:00
Plant Physiol. 2024 Feb 20:kiae083. doi: 10.1093/plphys/kiae083. Online ahead of print.ABSTRACTCarbon-flow-regulator A (CfrA) adapts carbon flux to nitrogen conditions in non-diazotrophic cyanobacteria. Under nitrogen deficiency, CfrA leads to the storage of excess carbon, which cannot combine with nitrogen, mainly as glycogen. cfrA overexpression from the arsenite-inducible, nitrogen-independent ParsB promoter allows analysis of the metabolic effects of CfrA accumulation. Considering that the main consequence of cfrA overexpression is glycogen accumulation, we examined carbon distribution in response to cfrA expression in Synechocystis sp. PCC 6803 strains impaired in synthesizing this polymer. We carried out a comparative phenotypic analysis to evaluate cfrA overexpression in the wild-type strain and in a mutant of ADP-glucose pyrophosphorylase (ΔglgC), which is unable to synthesize glycogen. The accumulation of CfrA in the wild-type background caused a photosynthetic readjustment although growth was not affected. However, in a ΔglgC strain, growth decreased depending on CfrA accumulation and photosynthesis was severely affected. An elemental analysis of the H, C, and N content of cells revealed that cfrA expression in the wildtype caused an increase in the C/N ratio, due to decreased nitrogen assimilation. Metabolomic study indicated that these cells store sucrose and glycosylglycerol, in addition to the previously described glycogen accumulation. However, cells deficient in glycogen synthesis accumulated large amounts of Calvin-Benson cycle intermediates as cfrA was expressed. These cells also showed increased levels of some amino acids, mainly alanine, serine, valine, isoleucine and leucine. The findings suggest that by controlling cfrA expression, in different conditions and strains, we could change the distribution of fixed carbon, with potential biotechnological benefits.PMID:38377468 | DOI:10.1093/plphys/kiae083

Serum aryl hydrocarbon receptor activity is associated with survival in patients with alcohol-associated hepatitis

Tue, 20/02/2024 - 12:00
Hepatology. 2024 Feb 20. doi: 10.1097/HEP.0000000000000777. Online ahead of print.ABSTRACTBACKGROUND: Patients with alcohol-associated hepatitis (AH) have an altered fecal metabolome, including reduced microbiota-derived tryptophan metabolites which function as ligands for aryl hydrocarbon receptor (AhR). The aim of this study was to assess serum AhR ligand activity in AH patients.METHODS: The study included 74 controls without alcohol use disorder (AUD), 97 patients with AUD and 330 AH patients from two different multicenter cohorts (InTeam: 134, AlcHepNet: 196). Serum AhR activity was evaluated using an AhR reporter assay with HepG2-Lucia cells incubated with serum for 24 hours.RESULTS: Serum AhR activity was significantly higher in patients with AH compared with both controls (1.59 vs. 0.96-fold change, p<0.001) and patients with AUD (1.59 vs. 0.93, p<0.001). In both AH cohorts, patients with AhR activity ≥ 2.09 had significantly lower cumulative survival rates at 30, 60, 90, and 180 days compared to those with AhR activity<2.09. When serum AhR activity was used to further stratify patients with severe AH, the cumulative 30, 60, 90, and 180-day survival rates for patients with severe AH and the AhR activity ≥ 2.09 group were all significantly lower than those with an AhR activity<2.09 group.CONCLUSION: Serum AhR activity was significantly higher in patients with AH compared with controls and individuals with AUD, and this increased activity was associated with higher mortality. Consequently, serum AhR activity holds potential as a prognostic marker.PMID:38377466 | DOI:10.1097/HEP.0000000000000777

Oleic acid-PPARγ-FABP4 loop fuels cholangiocarcinoma colonization in lymph node metastases microenvironment

Tue, 20/02/2024 - 12:00
Hepatology. 2024 Feb 20. doi: 10.1097/HEP.0000000000000784. Online ahead of print.ABSTRACTBACKGROUND AND AIMS: Lymph node metastasis is a significant risk factor for cholangiocarcinoma patients, but the mechanisms underlying cholangiocarcinoma colonization in the lymph node microenvironment remain unclear. We aimed to determine whether metabolic reprogramming fueled the adaptation and remodeling of cholangiocarcinoma cells to the lymph node microenvironment.APPROACH AND RESULTS: Here, we applied single-cell RNA sequencing (scRNA-seq) of primary tumor lesions and paired lymph node metastases from cholangiocarcinoma patients and revealed significantly reduced inter-tumor heterogeneity and syntropic lipid metabolic reprogramming of cholangiocarcinoma after metastasis to lymph nodes, which was verified by pan-cancer scRNA-seq analysis, highlighting the essential role of lipid metabolism in tumor colonization in lymph nodes. Metabolomics and in vivo CRISPR/Cas9 screening identified PPARγ as a crucial regulator in fueling cholangiocarcinoma colonization in lymph node through the oleic acid-PPARγ-FABP4 positive feedback loop by up-regulating fatty acid uptake and oxidation. Patient-derived organoids and animal models have demonstrated that blocking this loop impairs cholangiocarcinoma proliferation and colonization in the lymph node microenvironment and is superior to systemic inhibition of fatty acid oxidation. PPARγ-regulated fatty acid metabolic reprogramming in cholangiocarcinoma also contributes to the immune-suppressive niche in lymph node metastases by producing kynurenine, and was found to be associated with tumor relapse, immune-suppressive lymph node microenvironment, and poor immune checkpoint blockade response.CONCLUSIONS: Our results reveal the role of the oleic acid-PPARγ-FABP4 loop in fueling cholangiocarcinoma colonization in lymph nodes, and demonstrate that PPARγ-regulated lipid metabolic reprogramming is a promising therapeutic target for relieving cholangiocarcinoma lymph node metastasis burden and reducing further progression.PMID:38377465 | DOI:10.1097/HEP.0000000000000784

imputomics: web server and R package for missing values imputation in metabolomics data

Tue, 20/02/2024 - 12:00
Bioinformatics. 2024 Feb 20:btae098. doi: 10.1093/bioinformatics/btae098. Online ahead of print.ABSTRACTMOTIVATION: Missing values are commonly observed in metabolomics data from mass spectrometry (MS). Imputing them is crucial because it assures data completeness, increases the statistical power of analyses, prevents inaccurate results, and improves the quality of exploratory analysis, statistical modeling, and machine learning. Numerous Missing Value Imputation Algorithms (MVIAs) employ heuristics or statistical models to replace missing information with estimates. In the context of metabolomics data, we identified 52 MVIAs implemented across 70 R functions. Nevertheless, the usage of those 52 established methods poses challenges due to package dependency issues, lack of documentation and their instability.RESULTS: Our R package, imputomics, provides a convenient wrapper around 41 (plus random imputation as a baseline model) out of 52 MVIAs in the form of a command-line tool and a web application. In addition, we propose a novel functionality for selecting MVIAs recommended for metabolomics data with the best performance or execution time.AVAILABILITY: imputomics is freely available as an R package (github.com/BioGenies/imputomics) and a Shiny web application (biogenies.info/imputomics-ws). The documentation is available at biogenies.info/imputomics.SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.PMID:38377398 | DOI:10.1093/bioinformatics/btae098

Mitochondrial and cytosolic one-carbon metabolism is a targetable metabolic vulnerability in cisplatin-resistant ovarian cancer

Tue, 20/02/2024 - 12:00
Mol Cancer Ther. 2024 Feb 20. doi: 10.1158/1535-7163.MCT-23-0550. Online ahead of print.ABSTRACTOne-carbon (C1) metabolism is compartmentalized between the cytosol and mitochondria with the mitochondrial C1 pathway as the major source of glycine and C1 units for cellular biosynthesis. Expression of mitochondrial C1 genes including SLC25A32, serine hydroxymethyl transferase (SHMT) 2, 5,10-methylene tetrahydrofolate dehydrogenase 2, and 5,10-methylene tetrahydrofolate dehydrogenase 1-like was significantly elevated in primary epithelial ovarian cancer (EOC) specimens compared to normal ovaries. 5-Substituted pyrrolo[3,2-d]pyrimidine antifolates (AGF347, AGF359, AGF362) inhibited proliferation of cisplatin sensitive (A2780, CaOV3, IGROV1) and resistant (A2780-E80, SKOV3) EOC cells. In SKOV3 and A2780-E80 cells, colony formation was inhibited. AGF347 induced apoptosis in SKOV3 cells. In IGROV1 cells, AGF347 was transported by folate receptor (FR) α. AGF347 was also transported into IGROV1 and SKOV3 cells by the proton-coupled folate transporter (SLC46A1) and the reduced folate carrier (SLC19A1). AGF347 accumulated to high levels in the cytosol and mitochondria of SKOV3 cells. By targeted metabolomics with [2,3,3-2H]L-serine, AGF347, AGF359 and AGF362 inhibited SHMT2 in the mitochondria. In the cytosol, SHMT1 and de novo purine biosynthesis (i.e., glycinamide ribonucleotide formyltransferase, 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase) were targeted; AGF359 also inhibited thymidylate synthase. Antifolate treatments of SKOV3 cells depleted cellular glycine, mitochondrial NADH and glutathione, and showed synergistic in vitro inhibition toward SKOV3 and A2780-E80 cells when combined with cisplatin. In vivo studies with subcutaneous SKOV3 EOC xenografts in SCID mice confirmed significant antitumor efficacy of AGF347. Collectively, our studies demonstrate a unique metabolic vulnerability in EOC involving mitochondrial and cytosolic C1 metabolism that offers a promising new platform for therapy.PMID:38377173 | DOI:10.1158/1535-7163.MCT-23-0550

Deciphering the metabolism of <em>Lactobacillus delbrueckii</em> subsp. <em>delbrueckii</em> during soy juice fermentation using phenotypic and transcriptional analysis

Tue, 20/02/2024 - 12:00
Appl Environ Microbiol. 2024 Feb 20:e0193623. doi: 10.1128/aem.01936-23. Online ahead of print.ABSTRACTIn the context of sustainable diet, the development of soy-based yogurt fermented with lactic acid bacteria is an attractive alternative to dairy yogurts. To decipher the metabolism of Lactobacillus delbrueckii subsp. delbrueckii during soy juice (SJ) fermentation, the whole genome of the strain CIRM-BIA865 (Ld865) was sequenced and annotated. Then Ld865 was used to ferment SJ. Samples were analyzed throughout fermentation for their cell number, carbohydrate, organic acid, free amino acid, and volatile compound contents. Despite acidification, the number of Ld865 cells did not rise, and microscopic observations revealed the elongation of cells from 3.6 µm (inoculation) to 36.9 µm (end of fermentation). This elongation was observed in SJ but not in laboratory-rich medium MRS. Using transcriptomic analysis, we showed that the biosynthesis genes of peptidoglycan and membrane lipids were stably expressed, in line with the cell elongation observed, whereas no genes implicated in cell division were upregulated. Among the main sugars available in SJ (sucrose, raffinose, and stachyose), Ld865 only used sucrose. The transcriptomic analysis showed that Ld865 implemented the two transport systems that it contains to import sucrose: a PTS system and an ABC transporter. To fulfill its nitrogen needs, Ld865 probably first consumed the free amino acids of the SJ and then implemented different oligopeptide transporters and proteolytic/peptidase enzymes. In conclusion, this study showed that Ld865 enables fast acidification of SJ, despite the absence of cell division, leads to a product rich in free amino acids, and also leads to the production of aromatic compounds of interest.IMPORTANCETo reduce the environmental and health concerns related to food, an alternative diet is recommended, containing 50% of plant-based proteins. Soy juice, which is protein rich, is a relevant alternative to animal milk, for the production of yogurt-like products. However, soy "beany" and "green" off-flavors limit the consumption of such products. The lactic acid bacteria (LAB) used for fermentation can help to improve the organoleptic properties of soy products. But metabolic data concerning LAB adapted to soy juice are lacking. The aim of this study was, thus, to decipher the metabolism of Lactobacillus delbrueckii subsp. delbrueckii during fermentation of a soy juice, based on a multidisciplinary approach. This result will contribute to give tracks for a relevant selection of starter. Indeed, the improvement of the organoleptic properties of these types of products could help to promote plant-based proteins in our diet.PMID:38376234 | DOI:10.1128/aem.01936-23

Hypoglycemic effects and associated mechanisms of resveratrol and related stilbenes in diet

Tue, 20/02/2024 - 12:00
Food Funct. 2024 Feb 20. doi: 10.1039/d3fo04761j. Online ahead of print.ABSTRACTHyperglycemia has become a global health problem due to changes in diet and lifestyle. Most importantly, persistent hyperglycemia can eventually develop into type II diabetes. While the usage of current drugs is limited by their side effects, stilbenes derived from fruits and herbal/dietary plants are considered as important phytochemicals with potential hypoglycemic properties. Herein, the most common stilbenoids in consumed foods, i.e. resveratrol, pterostilbene, piceatannol, oxyresveratrol, and 2,3,5,4'-tetrahydroxystilbene-2-O-β-glucopyranoside (THSG), are reviewed in this paper. These stilbenes are found to regulate glucose homeostasis via (a) modulation of feeding behaviour and nutrition absorption; (b) restoration of insulin signalling by enhancing insulin production/insulin sensitivity; (c) improvement of gut permeability, gut microbial profile and resulting metabolomes; and (d) amelioration of circadian rhythm disruption. In this review, we have summarized the underlying mechanisms for the hypoglycemic effects of the five most common dietary stilbenoids listed above, providing a comprehensive framework for future study and applications.PMID:38376230 | DOI:10.1039/d3fo04761j

Application of metabolomics in oral squamous cell carcinoma

Tue, 20/02/2024 - 12:00
Oral Dis. 2024 Feb 20. doi: 10.1111/odi.14895. Online ahead of print.ABSTRACTBACKGROUND: Oral squamous cell carcinoma (OSCC) is a prevalent malignancy affecting the head and neck region. The prognosis for OSCC patients remains unfavorable due to the absence of precise and efficient early diagnostic techniques. Metabolomics offers a promising approach for identifying distinct metabolites, thereby facilitating early detection and treatment of OSCC.OBJECTIVE: This review aims to provide a comprehensive overview of recent advancements in metabolic marker identification for early OSCC diagnosis. Additionally, the clinical significance and potential applications of metabolic markers for the management of OSCC are discussed.RESULTS: This review summarizes metabolic changes during the occurrence and development of oral squamous cell carcinoma and reviews prospects for the clinical application of characteristic, differential metabolites in saliva, serum, and OSCC tissue. In this review, the application of metabolomic technology in OSCC research was summarized, and future research directions were proposed.CONCLUSION: Metabolomics, detection technology that is the closest to phenotype, can efficiently identify differential metabolites. Combined with statistical data analyses and artificial intelligence technology, it can rapidly screen characteristic biomarkers for early diagnosis, treatment, and prognosis evaluations.PMID:38376209 | DOI:10.1111/odi.14895

Identifying and mathematically modeling the time-course of extracellular metabolic markers associated with resistance to ceftolozane/tazobactam in <em>Pseudomonas aeruginosa</em>

Tue, 20/02/2024 - 12:00
Antimicrob Agents Chemother. 2024 Feb 20:e0108123. doi: 10.1128/aac.01081-23. Online ahead of print.ABSTRACTExtracellular bacterial metabolites have potential as markers of bacterial growth and resistance emergence but have not been evaluated in dynamic in vitro studies. We investigated the dynamic metabolomic footprint of a multidrug-resistant hypermutable Pseudomonas aeruginosa isolate exposed to ceftolozane/tazobactam as continuous infusion (4.5 g/day, 9 g/day) in a hollow-fiber infection model over 7-9 days in biological replicates (n = 5). Bacterial samples were collected at 0, 7, 23, 47, 71, 95, 143, 167, 191, and 215 h, the supernatant quenched, and extracellular metabolites extracted. Metabolites were analyzed via untargeted metabolomics, including hierarchical clustering and correlation with quantified total and resistant bacterial populations. The time-courses of five (of 1,921 detected) metabolites from enriched pathways were mathematically modeled. Absorbed L-arginine and secreted L-ornithine were highly correlated with the total bacterial population (r -0.79 and 0.82, respectively, P<0.0001). Ribose-5-phosphate, sedoheptulose-7-phosphate, and trehalose-6-phosphate correlated with the resistant subpopulation (0.64, 0.64, and 0.67, respectively, P<0.0001) and were likely secreted due to resistant growth overcoming oxidative and osmotic stress induced by ceftolozane/tazobactam. Using pharmacokinetic/pharmacodynamic-based transduction models, these metabolites were successfully modeled based on the total or resistant bacterial populations. The models well described the abundance of each metabolite across the differing time-course profiles of biological replicates, based on bacterial killing and, importantly, resistant regrowth. These proof-of-concept studies suggest that further exploration is warranted to determine the generalizability of these findings. The metabolites modeled here are not exclusive to bacteria. Future studies may use this approach to identify bacteria-specific metabolites correlating with resistance, which would ultimately be extremely useful for clinical translation.PMID:38376189 | DOI:10.1128/aac.01081-23

miR828a-CsMYB114 Module Negatively Regulates the Biosynthesis of Theobromine in <em>Camellia sinensis</em>

Tue, 20/02/2024 - 12:00
J Agric Food Chem. 2024 Feb 20. doi: 10.1021/acs.jafc.3c07736. Online ahead of print.ABSTRACTTheobromine is an important quality component in tea plants (Camellia sinensis), which is produced from 7-methylxanthine by theobromine synthase (CsTbS), the key rate-limiting enzyme in theobromine biosynthetic pathway. Our transcriptomics and widely targeted metabolomics analyses suggested that CsMYB114 acted as a potential hub gene involved in the regulation of theobromine biosynthesis. The inhibition of CsMYB114 expression using antisense oligonucleotides (ASO) led to a 70.21% reduction of theobromine level in leaves of the tea plant, which verified the involvement of CsMYB114 in theobromine biosynthesis. Furthermore, we found that CsMYB114 was located in the nucleus of the cells and showed the characteristic of a transcription factor. The dual luciferase analysis, a yeast one-hybrid assay, and an electrophoretic mobility shift assay (EMSA) showed that CsMYB114 activated the transcription of CsTbS, through binding to CsTbS promoter. In addition, a microRNA, miR828a, was identified that directly cleaved the mRNA of CsMYB114. Therefore, we conclude that CsMYB114, as a transcription factor of CsTbS, promotes the production of theobromine, which is inhibited by miR828a through cleaving the mRNA of CsMYB114.PMID:38376143 | DOI:10.1021/acs.jafc.3c07736

Disturbed Follicular Microenvironment in Polycystic Ovary Syndrome: Relationship to Oocyte Quality and Infertility

Tue, 20/02/2024 - 12:00
Endocrinology. 2024 Feb 20:bqae023. doi: 10.1210/endocr/bqae023. Online ahead of print.ABSTRACTPolycystic ovary syndrome (PCOS) is a common endocrine disorder associated with infertility and poor reproductive outcomes. The follicular fluid (FF) microenvironment plays a crucial role in oocyte development. This review summarizes evidence elucidating the alterations in FF composition in PCOS. Various studies demonstrated a pronounced proinflammatory milieu in PCOS FF, characterized by increased levels of cytokines, including but not limited to IL-6, TNF-α, CRP, and IL-1β, concomitant with a reduction in anti-inflammatory IL-10. T lymphocytes and antigen presenting cells are dysregulated in PCOS FF. PCOS FF exhibited heightened reactive oxygen species (ROS) production and the accumulation of lipid peroxidation byproducts, and impaired antioxidant defenses. Multiple miRNAs are dysregulated in PCOS FF, disrupting signaling critical to granulosa cell function. Proteomic analysis reveals changes in pathways related to immune responses, metabolic perturbations, angiogenesis, and hormone regulation. Metabolomics identify disturbances in glucose metabolism, amino acids, lipid profiles, and steroid levels with PCOS FF. Collectively, these pathological alterations may adversely impact oocyte quality, embryo development, and fertility outcomes. Further research on larger cohorts is needed to validate these findings and to forge the development of prognostic biomarkers of oocyte developmental competence within FF. Characterizing the follicular environment in PCOS is key to elucidate the mechanisms underlying subfertility in this challenging disorder.PMID:38375912 | DOI:10.1210/endocr/bqae023

Debunking the Myth of <em>Fusarium poae</em> T-2/HT-2 Toxin Production

Tue, 20/02/2024 - 12:00
J Agric Food Chem. 2024 Feb 20. doi: 10.1021/acs.jafc.3c08437. Online ahead of print.ABSTRACTFusarium poae is commonly detected in field surveys of Fusarium head blight (FHB) of cereal crops and can produce a range of trichothecene mycotoxins. Although experimentally validated reports of F. poae strains producing T-2/HT-2 trichothecenes are rare, F. poae is frequently generalized in the literature as a producer of T-2/HT-2 toxins due to a single study from 2004 in which T-2/HT-2 toxins were detected at low levels from six out of forty-nine F. poae strains examined. To validate/substantiate the observations reported from the 2004 study, the producing strains were acquired and phylogenetically confirmed to be correctly assigned as F. poae; however, no evidence of T-2/HT-2 toxin production was observed from axenic cultures. Moreover, no evidence for a TRI16 ortholog, encoding a key acyltransferase shown to be necessary for T-2 toxin production in other Fusarium species, was observed in any of the de novo assembled genomes of the F. poae strains. Our findings corroborate multiple field-based and in vitro studies on FHB-associated Fusarium populations which also do not support the production of T-2/HT-2 toxins with F. poae and therefore conclude that F. poae should not be generalized as a T-2/HT-2 toxin producing species of Fusarium.PMID:38375818 | DOI:10.1021/acs.jafc.3c08437

A widely targeted metabolite modificomics strategy for modified metabolites identification in tomato

Tue, 20/02/2024 - 12:00
J Integr Plant Biol. 2024 Feb 20. doi: 10.1111/jipb.13629. Online ahead of print.ABSTRACTThe structural and functional diversity of plant metabolites is largely created via chemical modification of a basic backbone. However, metabolite modifications in plants have still not been thoroughly investigated by metabolomics approaches. In this study, a widely targeted metabolite modificomics (WTMM) strategy was developed based on ultra-high performance liquid chromatography-quadrupole-linear ion trap (UHPLC-Q-Trap) and UHPLC-Q-Exactive-Orbitrap (UHPLC-QE-Orbitrap), which greatly improved the detection sensitivity and the efficiency of identification of modified metabolites. A metabolite modificomics study was carried out using tomato as a model, and over 34,000 signals with MS2 information were obtained from approximately 232 neutral loss transitions. Unbiased metabolite profiling was also performed by utilizing high-resolution mass spectrometry data to annotate a total of 2,118 metabolites with 125 modification types; of these, 165 modified metabolites were identified in this study. Next, the WTMM database was used to assess diseased tomato tissues and 29 biomarkers were analyzed. In summary, the WTMM strategy is not only capable of large-scale detection and quantitative analysis of plant-modified metabolites in plants, but also can be used for plant biomarker development.PMID:38375781 | DOI:10.1111/jipb.13629

Lipidomic signatures discriminate subtle hepatic changes in the progression of porcine non-alcoholic steatohepatitis

Tue, 20/02/2024 - 12:00
Am J Physiol Gastrointest Liver Physiol. 2024 Feb 20. doi: 10.1152/ajpgi.00264.2023. Online ahead of print.ABSTRACTRecently, the development of non-alcoholic steatohepatitis (NASH) in common strains of pigs has been achieved using a diet high in saturated fat, fructose, cholesterol and cholate and deficient in choline and methionine. The aim of the present work was to characterize the hepatic and plasma lipidomic changes that accompany the progression of NASH and its reversal by switching pigs back to a chow diet. One month of this extreme steatotic diet was sufficient to induce porcine NASH. The lipidomic platform using liquid chromatography-mass spectrometry analyzed 467 lipid species. Seven hepatic phospholipids [PC(30:0), PC(32:0), PC(33:0), PC(33:1), PC(34:0), PC(34:3) and PC(36:2)] significantly discriminated the time of dietary exposure, and PC(30:0), PC(33:0), PC(33:1) and PC(34:0) showed rapid adaptation in the reversion period. Three transcripts, CS, MAT1A and SPP1, showed significant changes associated with hepatic triglycerides and PC(33:0). Plasma lipidomics revealed that these species [FA 16:0, FA 18:0, LPC(17:1), PA(40:5), PC(37:1), TG(45:0), TG(47:2) and TG(51:0)] were able to discriminate the time of dietary exposure. Among them, FA 16:0, FA 18:0, LPC(17:1) and PA(40:5) changed the trend in the reversion phase. Plasma LDL-cholesterol and IL12P40 were good parameters to study the progression of NASH, but their capacity was surpassed by hepatic [PC(33:0), PC(33:1), and PC(34:0)] or plasma lipid [FA 16:0, FA 18:0, and LPC(17:1)] species. Taken together, these lipid species can be used as biomarkers of metabolic changes in the progression and regression of NASH in this model. The lipid changes suggest that the development of NASH also affects peripheral lipid metabolism.PMID:38375587 | DOI:10.1152/ajpgi.00264.2023

Amino acid degradation pathway inhibitory by-products trigger apoptosis in CHO cells

Tue, 20/02/2024 - 12:00
Biotechnol J. 2024 Jan;19(2):e2300338. doi: 10.1002/biot.202300338.ABSTRACTChinese hamster ovary (CHO) cells are widely used to produce complex biopharmaceuticals. Improving their productivity is necessary to fulfill the growing demand for such products. One way to enhance productivity is by cultivating cells at high densities, but inhibitory by-products, such as metabolite derivatives from amino acid degradation, can hinder achieving high cell densities. This research examines the impact of these inhibitory by-products on high-density cultures. We cultured X1 and X2 CHO cell lines in a small-scale semi-perfusion system and introduced a mix of inhibitory by-products on day 10. The X1 and X2 cell lines were chosen for their varied responses to the by-products; X2 was susceptible, while X1 survived. Proteomics revealed that the X2 cell line presented changes in the proteins linked to apoptosis regulation, cell building block synthesis, cell growth, DNA repair, and energy metabolism. We later used the AB cell line, an apoptosis-resistant cell line, to validate the results. AB behaved similar to X1 under stress. We confirmed the activation of apoptosis in X2 using a caspase assay. This research provides insights into the mechanisms of cell death triggered by inhibitory by-products and can guide the optimization of CHO cell culture for biopharmaceutical manufacturing.PMID:38375561 | DOI:10.1002/biot.202300338

Influence of glutamine metabolism on diabetes Development:A scientometric review

Tue, 20/02/2024 - 12:00
Heliyon. 2024 Feb 3;10(4):e25258. doi: 10.1016/j.heliyon.2024.e25258. eCollection 2024 Feb 29.ABSTRACTOBJECTIVE: "Metabolism affects function" is the consensus of researchers at present. It has potential clinical application value to study the effects of regulating glutamine (Gln) metabolism on diabetes physiology or pathology. Our research aimed to summarize the latest research progress, frontier hot topics and future development trends in this field from the perspective of scientometrics.METHODS: Relevant literatures and reviews were obtained from the Web of Science (WoS) between January 1, 2001 and May 31, 2022. An online analysis platform of bibliometrics, CiteSpace, and VOS viewer software were used to generate visual knowledge network graphs, including publication countries, institutions and authors partnership analysis, co-occurrence analysis, co-citation analysis, as well as citations and keywords burst detection to acquire research trends and hotspots.RESULTS: Our results showed that a total of 945 publications in the WoS database met the analysis requirements, with articles being the main type. The overall characteristics showed an increasing trend in the number of publications and citations. The United States was leading the way in this research and was a hub for aggregating collaborations across countries. Vanderbilt University delivered high-quality impact with the most published articles. DeBerardinis, RJ in this field was the most representative author and his main research contents were Gln metabolism and mitochondrial glutaminolysis. Significantly, there was a relative lack of collaboration between institutions and authors. In addition, "type 2 diabetes", "glutamine", "metabolism", "gene expression" and "metabolomics" were the keywords categories with high frequency in co-citation references and co-occurrence cluster keywords. Analysis of popular keywords burst detection showed that "branched chain", "oxidative phosphorylation", "kinase", "insulin sensitivity", "tca cycle", "magnetic resonance spectroscopy" and "flux analysis" were new research directions and emerging methods to explore the link between Gln metabolism and diabetes. Overall, exploring Gln metabolism showed a gradual upward trend in the field of diabetes.CONCLUSION: This comprehensive scientometric study identified the general outlook for the field and provided valuable guidance for ongoing research. Strategies to regulate Gln metabolism hold promise as a novel target to treat diabetes, as well as integration and intersection of multidisciplinary provides cooperation strategies and technical guarantees for the development of this field.PMID:38375272 | PMC:PMC10875382 | DOI:10.1016/j.heliyon.2024.e25258

New mechanistic insights of anti-obesity by sleeve gastrectomy-altered gut microbiota and lipid metabolism

Tue, 20/02/2024 - 12:00
Front Endocrinol (Lausanne). 2024 Feb 2;15:1338147. doi: 10.3389/fendo.2024.1338147. eCollection 2024.ABSTRACTBACKGROUND: The obesity epidemic has been on the rise due to changes in living standards and lifestyles. To combat this issue, sleeve gastrectomy (SG) has emerged as a prominent bariatric surgery technique, offering substantial weight reduction. Nevertheless, the mechanisms that underlie SG-related bodyweight loss are not fully understood.METHODS: In this study, we conducted a collection of preoperative and 3-month postoperative serum and fecal samples from patients who underwent laparoscopic SG at the First Affiliated Hospital of Shandong First Medical University (Jinan, China). Here, we took an unbiased approach of multi-omics to investigate the role of SG-altered gut microbiota in anti-obesity of these patients. Non-target metabolome sequencing was performed using the fecal and serum samples.RESULTS: Our data show that SG markedly increased microbiota diversity and Rikenellaceae, Alistipes, Parabacteroides, Bactreoidales, and Enterobacteraies robustly increased. These compositional changes were positively correlated with lipid metabolites, including sphingolipids, glycerophospholipids, and unsaturated fatty acids. Increases of Rikenellaceae, Alistipes, and Parabacteroide were reversely correlated with body mass index (BMI).CONCLUSION: In conclusion, our findings provide evidence that SG induces significant alterations in the abundances of Rikenellaceae, Alistipes, Parabacteroides, and Bacteroidales, as well as changes in lipid metabolism-related metabolites. Importantly, these changes were found to be closely linked to the alleviation of obesity. On the basis of these findings, we have identified a number of microbiotas that could be potential targets for treatment of obesity.PMID:38375198 | PMC:PMC10875461 | DOI:10.3389/fendo.2024.1338147

The role of blood metabolites in oral cancer: insights from a Mendelian randomization approach

Tue, 20/02/2024 - 12:00
Front Oncol. 2024 Feb 5;14:1305684. doi: 10.3389/fonc.2024.1305684. eCollection 2024.ABSTRACTAIM: This research aimed to explore the causal impact of blood metabolites on oral cancer using a two-sample Mendelian randomization (MR) analysis. The study endeavored to identify potential biomarkers for oral cancer's clinical management.MATERIALS AND METHODS: Based on the large individual-level datasets from UK Biobank as well as GWAS summary datasets, we first constructed genetic risk scores (GRSs) of 486 human blood metabolites and evaluated the effect on oral cancer. Various statistical methods, including inverse variance weighted (IVW), MR-Egger, and weighted median, among others, were employed to analyze the potential causal relationship between blood metabolites and oral cancer. The sensitivity analyses were conducted using Cochran's Q tests, funnel plots, leave-one-out analyses, and MR-Egger intercept tests.RESULTS: 29 metabolites met the stringent selection criteria. Out of these, 14 metabolites demonstrated a positive association with oral cancer risk, while 15 metabolites indicated a protective effect against oral cancer. The IVW-derived estimates were significant, and the results were consistent across different statistical methodologies. Both the Cochran Q test and the MR-Egger intercept test indicated no heterogeneity and pleiotropy.CONCLUSION: This MR study offers evidence of the role specific blood metabolites play in oral cancer, pinpointing several with potential risk or protective effects. These findings could be helpful for new diagnostic tools and treatments for oral cancer. While the results are promising, additional research is necessary to fully validate and refine these conclusions. This study serves as a foundational step towards more comprehensive understandings in the future.PMID:38375154 | PMC:PMC10876297 | DOI:10.3389/fonc.2024.1305684

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