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

Dinotefuran exposure alters biochemical, metabolomic, gut microbiome, and growth responses in decapoda pacific white shrimp Penaeus vannamei

Thu, 07/03/2024 - 12:00
J Hazard Mater. 2024 Mar 2;469:133930. doi: 10.1016/j.jhazmat.2024.133930. Online ahead of print.ABSTRACTDinotefuran, a neonicotinoid insecticide, may impact nontarget organisms such as Decapoda P. vannamei shrimp with nervous systems similar to insects. Exposing shrimp to low dinotefuran concentrations (6, 60, and 600 μg/L) for 21 days affected growth, hepatosomatic index, and survival. Biomarkers erythromycin-N-demethylase, alanine aminotransferase, and catalase increased in all exposed groups, while glutathione S-transferase is the opposite; aminopyrin-N-demethylase, malondialdehyde, and aspartate aminotransferase increased at 60 and 600 μg/L. Concentration-dependent effects on gut microbiota altered the abundance of bacterial groups, increased potentially pathogenic and oxidative stress-resistant phenotypes, and decreased biofilm formation. Gram-positive/negative microbiota changed significantly. Metabolite differences between the exposed and control groups were identified using mass spectrometry and KEGG pathway enrichment. N-acetylcystathionine showed potential as a reliable dinotefuran metabolic marker. Weighted correlation network analysis (WGCNA) results indicated high connectivity of cruecdysone in the metabolite network and significant enrichment at 600 μg/L dinotefuran. The WGCNA results revealed a highly significant negative correlation between two key metabolites, caldine and indican, and the gut microbiota within co-expression modules. Overall, the risk of dinotefuran exposure to non-target organisms in aquatic environments still requires further attention.PMID:38452673 | DOI:10.1016/j.jhazmat.2024.133930

Maternal prebiotic supplementation during pregnancy and lactation modifies the microbiome and short chain fatty acid profile of both mother and infant

Thu, 07/03/2024 - 12:00
Clin Nutr. 2024 Mar 1;43(4):969-980. doi: 10.1016/j.clnu.2024.02.030. Online ahead of print.ABSTRACTBACKGROUND & AIMS: Improving maternal gut health in pregnancy and lactation is a potential strategy to improve immune and metabolic health in offspring and curtail the rising rates of inflammatory diseases linked to alterations in gut microbiota. Here, we investigate the effects of a maternal prebiotic supplement (galacto-oligosaccharides and fructo-oligosaccharides), ingested daily from <21 weeks' gestation to six months' post-partum, in a double-blinded, randomised placebo-controlled trial.METHODS: Stool samples were collected at multiple timepoints from 74 mother-infant pairs as part of a larger, double-blinded, randomised controlled allergy intervention trial. The participants were randomised to one of two groups; with one group receiving 14.2 g per day of prebiotic powder (galacto-oligosaccharides GOS and fructo-oligosaccharides FOS in ratio 9:1), and the other receiving a placebo powder consisting of 8.7 g per day of maltodextrin. The faecal microbiota of both mother and infants were assessed based on the analysis of bacterial 16S rRNA gene (V4 region) sequences, and short chain fatty acid (SCFA) concentrations in stool.RESULTS: Significant differences in the maternal microbiota profiles between baseline and either 28-weeks' or 36-weeks' gestation were found in the prebiotic supplemented women. Infant microbial beta-diversity also significantly differed between prebiotic and placebo groups at 12-months of age. Supplementation was associated with increased abundance of commensal Bifidobacteria in the maternal microbiota, and a reduction in the abundance of Negativicutes in both maternal and infant microbiota. There were also changes in SCFA concentrations with maternal prebiotics supplementation, including significant differences in acetic acid concentration between intervention and control groups from 20 to 28-weeks' gestation.CONCLUSION: Maternal prebiotic supplementation of 14.2 g per day GOS/FOS was found to favourably modify both the maternal and the developing infant gut microbiome. These results build on our understanding of the importance of maternal diet during pregnancy, and indicate that it is possible to intervene and modify the development of the infant microbiome by dietary modulation of the maternal gut microbiome.PMID:38452522 | DOI:10.1016/j.clnu.2024.02.030

A metabolomics footprinting approach using GC-MS to study inhibitory effects of the fungal metabolite diplopyrone C against nosocomial pathogen biofilms

Thu, 07/03/2024 - 12:00
J Pharm Biomed Anal. 2024 Mar 2;243:116081. doi: 10.1016/j.jpba.2024.116081. Online ahead of print.ABSTRACTSeen initially as wonder drugs, the widespread and often inappropriate use of antibiotics led to the development of microbial resistances. As a result, a true emergency has arisen, and a significant need has emerged to discover and develop new safe and valuable antibiotics. The captivating chemical structure of the fungal metabolite diplopyrone C has caught our attention as an excellent candidate for a circumstantial study aimed at revealing its antimicrobial and antibiofilm activities. In this work, we describe the full analytical strategy from the isolation/identification to the evaluation of the metabolomics effect on target microorganisms of this fungal metabolite. Our results show interesting antimicrobial and antibiofilm activities of diplopyrone C against two frequently isolated nosocomial pathogens (i.e., the fungus Candida albicans and the gram-negative bacterium Klebsiella pneumoniae). Moreover, a GC-MS based metabolomics footprinting approach gave an insight into the uptake and excretion of metabolites from and into the culture medium as a response to the presence of this active substance. The workflow employed in this study is suitable to exploit natural resources for the search of lead compounds for drug development.PMID:38452422 | DOI:10.1016/j.jpba.2024.116081

A Plasma Exosomal Metabolic Profiling of Nonalcoholic Fatty Liver Disease Patients Complicated with Impaired Fasting Glucose

Thu, 07/03/2024 - 12:00
Turk J Gastroenterol. 2024 Feb;35(2):125-135. doi: 10.5152/tjg.2024.22739.ABSTRACTBACKGROUND/AIMS: Nonalcoholic fatty liver disease is considered as the hepatic manifestation of metabolic syndrome. Detection of circulating exosomes together with metabolomic analysis of their cargo would provide early signals for metabolic derangements and complications associated with nonalcoholic fatty liver disease. Therefore, this study profiled exosomal metabolome of patients with nonalcoholic fatty liver disease and impaired fasting glucose.MATERIALS AND METHODS: Plasma exosomes were extracted from nonalcoholic fatty liver disease patients with or without impaired fasting glucose through differential ultracentrifugation. Their metabolite profiles were examined by ultrahigh-performance liquid chrom atography-quadrupole time-of-flight mass spectrometry. Pathway analysis was carried out on platform MetaboAnalyst 4.0.RESULTS: Thirty-nine patients were enrolled, including nonalcoholic fatty liver disease-alone group (n = 26) and age-and gender-comparable nonalcoholic fatty liver disease plus impaired fasting glucose group (n = 13). Although less than and different from their plasma counterparts, a total of 10 significantly differential exosomal metabolites were identified. Nonalcoholic fatty liver disease plus impaired fasting glucose group had higher concentrations of linoleic acid, palmitamide, stearamide, and oleamide, as well as a lower concentration of phosphatidylethanolamine [20:5(5Z,8Z,11Z,14Z,17Z)/20:5(5Z,8Z,11Z,14Z,17Z)]. Pathway analysis showed an obviously changed metabolism of linoleic acid.CONCLUSION: Metabolomic analysis of plasma exosomes revealed a distinct change in fatty acids and related pathways in nonalcoholic fatty liver disease patients with impaired fasting glucose. These preliminary results provide a metabolomic snapshot and basis for further investigation of exosome biology for these patients.PMID:38454244 | DOI:10.5152/tjg.2024.22739

A metabolic map and artificial intelligence-aided identification of nasopharyngeal carcinoma via a single-cell Raman platform

Thu, 07/03/2024 - 12:00
Br J Cancer. 2024 Mar 7. doi: 10.1038/s41416-024-02637-3. Online ahead of print.ABSTRACTBACKGROUND: Nasopharyngeal carcinoma (NPC) is a complex cancer influenced by various factors. This study explores the use of single-cell Raman spectroscopy as a potential diagnostic tool for investigating biomolecular changes associated with NPC carcinogenesis.METHODS: Seven NPC cell lines, one immortalised nasopharyngeal epithelial cell line, six nasopharyngeal mucosa tissues and seven NPC tissue samples were analysed by performing confocal Raman spectroscopic measurements and imaging. The single-cell Raman spectral dataset was used to quantify relevant biomolecules and build machine learning classification models. Metabolomic profiles were investigated using ultra-performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS).RESULTS: By generating a metabolic map of seven NPC cell lines, we identified an interplay of altered metabolic processes involving nucleic acids, amino acids, lipids and sugars. The results from spatially resolved Raman maps and UPLC-MS/MS metabolomics were consistent, revealing an increase of unsaturated fatty acids in cancer cells, particularly in highly metastatic 5-8F and poorly differentiated CNE2 cells. The classification model achieved a nearly perfect classification when identifying NPC and non-NPC cells with an ROC-AUC of 0.99 and a value of 0.97 when identifying 13 tissue samples.CONCLUSION: This study unveils a complex interplay of metabolic network and highlights the potential roles of unsaturated fatty acids in NPC progression and metastasis. This renders further research to provide deeper insights into NPC pathogenesis, identify new metabolic targets and improve the efficacy of targeted therapies in NPC. Artificial intelligence-aided analysis of single-cell Raman spectra has achieved high accuracies in the classification of both cancer cells and patient tissues, paving the way for a simple, less invasive and accurate diagnostic test.PMID:38454165 | DOI:10.1038/s41416-024-02637-3

Publisher Correction: Suspect screening analysis to improve untargeted and targeted UHPLC-qToF approaches: the biodegradability of a proton pump inhibitor medicine and a natural medical device

Thu, 07/03/2024 - 12:00
Sci Rep. 2024 Mar 7;14(1):5660. doi: 10.1038/s41598-024-53924-1.NO ABSTRACTPMID:38454019 | DOI:10.1038/s41598-024-53924-1

A ketogenic diet rich in fish oil is superior to other fats in preventing NNK-induced lung cancer in A/J mice

Thu, 07/03/2024 - 12:00
Sci Rep. 2024 Mar 7;14(1):5610. doi: 10.1038/s41598-024-55167-6.ABSTRACTGiven that ketogenic diets (KDs) are extremely high in dietary fat, we compared different fats in KDs to determine which was the best for cancer prevention. Specifically, we compared a Western and a 15% carbohydrate diet to seven different KDs, containing either Western fats or fats enriched in medium chain fatty acids (MCTs), milk fat (MF), palm oil (PO), olive oil (OO), corn oil (CO) or fish oil (FO) for their ability to reduce nicotine-derived nitrosamine ketone (NNK)-induced lung cancer in mice. While all the KDs tested were more effective at reducing lung nodules than the Western or 15% carbohydrate diet, the FO-KD was most effective at reducing lung nodules. Correlating with this, mice on the FO-KD had low blood glucose and the highest β-hydroxybutyrate level, lowest liver fatty acid synthase/carnitine palmitoyl-1a ratio and a dramatic increase in fecal Akkermansia. We found no liver damage induced by the FO-KD, while the ratio of total cholesterol/HDL was unchanged on the different diets. We conclude that a FO-KD is superior to KDs enriched in other fats in reducing NNK-induced lung cancer, perhaps by being the most effective at skewing whole-body metabolism from a dependence on glucose to fats as an energy source.PMID:38453966 | DOI:10.1038/s41598-024-55167-6

Genomic insights and anti-phytopathogenic potential of siderophore metabolome of endolithic Nocardia mangyaensis NH1

Thu, 07/03/2024 - 12:00
Sci Rep. 2024 Mar 7;14(1):5676. doi: 10.1038/s41598-024-54095-9.ABSTRACTActinobacteria are one of the predominant groups that successfully colonize and survive in various aquatic, terrestrial and rhizhospheric ecosystems. Among actinobacteria, Nocardia is one of the most important agricultural and industrial bacteria. Screening and isolation of Nocardia related bacteria from extreme habitats such as endolithic environments are beneficial for practical applications in agricultural and environmental biotechnology. In this work, bioinformatics analysis revealed that a novel strain Nocardia mangyaensis NH1 has the capacity to produce structurally varied bioactive compounds, which encoded by non-ribosomal peptide synthases (NRPS), polyketide synthase (PKS), and post-translationally modified peptides (RiPPs). Among NRPS, five gene clusters have a sequence homology with clusters encoding for siderophore synthesis. We also show that N. mangyaensis NH1 accumulates both catechol- and hydroxamate-type siderophores simultaneously under iron-deficient conditions. Untargeted LC-MS/MS analysis revealed a variety of metabolites, including siderophores, lipopeptides, cyclic peptides, and indole-3-acetic acid (IAA) in the culture medium of N. mangyaensis NH1 grown under iron deficiency. We demonstrate that four CAS (chrome azurol S)-positive fractions display variable affinity to metals, with a high Fe3+ chelating capability. Additionally, three of these fractions exhibit antioxidant activity. A combination of iron scavenging metabolites produced by N. mangyaensis NH1 showed antifungal activity against several plant pathogenic fungi. We have shown that the pure culture of N. mangyaensis NH1 and its metabolites have no adverse impact on Arabidopsis seedlings. The ability of N. mangyaensis NH1 to produce siderophores with antifungal, metal-chelating, and antioxidant properties, when supplemented with phytohormones, has the potential to improve the release of macro- and micronutrients, increase soil fertility, promote plant growth and development, and enable the production of biofertilizers across diverse soil systems.PMID:38453942 | DOI:10.1038/s41598-024-54095-9

Targeting carnitine palmitoyl transferase 1A (CPT1A) induces ferroptosis and synergizes with immunotherapy in lung cancer

Thu, 07/03/2024 - 12:00
Signal Transduct Target Ther. 2024 Mar 7;9(1):64. doi: 10.1038/s41392-024-01772-w.ABSTRACTDespite the successful application of immune checkpoint therapy, no response or recurrence is typical in lung cancer. Cancer stem cells (CSCs) have been identified as a crucial player in immunotherapy-related resistance. Ferroptosis, a form of cell death driven by iron-dependent lipid peroxidation, is highly regulated by cellular metabolism remolding and has been shown to have synergistic effects when combined with immunotherapy. Metabolic adaption of CSCs drives tumor resistance, yet the mechanisms of their ferroptosis defense in tumor immune evasion remain elusive. Here, through metabolomics, transcriptomics, a lung epithelial-specific Cpt1a-knockout mouse model, and clinical analysis, we demonstrate that CPT1A, a key rate-limiting enzyme of fatty acid oxidation, acts with L-carnitine, derived from tumor-associated macrophages to drive ferroptosis-resistance and CD8+ T cells inactivation in lung cancer. Mechanistically, CPT1A restrains ubiquitination and degradation of c-Myc, while c-Myc transcriptionally activates CPT1A expression. The CPT1A/c-Myc positive feedback loop further enhances the cellular antioxidant capacity by activating the NRF2/GPX4 system and reduces the amount of phospholipid polyunsaturated fatty acids through ACSL4 downregulating, thereby suppressing ferroptosis in CSCs. Significantly, targeting CPT1A enhances immune checkpoint blockade-induced anti-tumor immunity and tumoral ferroptosis in tumor-bearing mice. The results illustrate the potential of a mechanism-guided therapeutic strategy by targeting a metabolic vulnerability in the ferroptosis of CSCs to improve the efficacy of lung cancer immunotherapy.PMID:38453925 | DOI:10.1038/s41392-024-01772-w

TREM2 deficiency impairs the energy metabolism of Schwann cells and exacerbates peripheral neurological deficits

Thu, 07/03/2024 - 12:00
Cell Death Dis. 2024 Mar 7;15(3):193. doi: 10.1038/s41419-024-06579-9.ABSTRACTTriggering receptor expressed on myeloid cells-2 (TREM2) has been implicated in susceptibility to neurodegenerative disease. Schwann cells (SCs), the predominant glial cell type in the peripheral nervous system (PNS), play a crucial role in myelination, providing trophic support for neurons and nerve regeneration. However, the function of TREM2 in SCs has not been fully elucidated. Here, we found that TREM2 is expressed in SCs but not in neurons in the PNS. TREM2 deficiency leads to disruption of glycolytic flux and oxidative metabolism in SCs, impairing cell proliferation. The energy crisis caused by TREM2 deficiency triggers mitochondrial damage and autophagy by activating AMPK and impairing PI3K-AKT-mTOR signaling. Combined metabolomic analysis demonstrated that energic substrates and energy metabolic pathways were significantly impaired in TREM2-deficient SCs. Moreover, TREM2 deficiency impairs energy metabolism and axonal growth in sciatic nerve, accompanied by exacerbation of neurological deficits and suppression of nerve regeneration in a mouse model of acute motor axonal neuropathy. These results indicate that TREM2 is a critical regulator of energy metabolism in SCs and exerts neuroprotective effects on peripheral neuropathy. TREM2 deficiency impairs glycolysis and oxidative metabolism in Schwann cells, resulting in compromised cell proliferation. The energy crisis caused by TREM2 deficiency induces mitochondrial damage and autophagy by activating AMPK and impairing PI3K-AKT-mTOR signaling. Moreover, TREM2 deficiency disrupts the energy metabolism of the sciatic nerve and impairs support for axonal regeneration, accompanied by exacerbation of neurological deficits and suppression of nerve regeneration in a mouse model of acute motor axonal neuropathy (by FigDraw).PMID:38453910 | DOI:10.1038/s41419-024-06579-9

Psat1-generated α-ketoglutarate and glutamine promote muscle stem cell activation and regeneration

Thu, 07/03/2024 - 12:00
Genes Dev. 2024 Mar 7. doi: 10.1101/gad.351428.123. Online ahead of print.ABSTRACTBy satisfying bioenergetic demands, generating biomass, and providing metabolites serving as cofactors for chromatin modifiers, metabolism regulates adult stem cell biology. Here, we report that a branch of glycolysis, the serine biosynthesis pathway (SBP), is activated in regenerating muscle stem cells (MuSCs). Gene inactivation and metabolomics revealed that Psat1, one of the three SBP enzymes, controls MuSC activation and expansion of myogenic progenitors through production of the metabolite α-ketoglutarate (α-KG) and α-KG-generated glutamine. Psat1 ablation resulted in defective expansion of MuSCs and impaired regeneration. Psat1, α-KG, and glutamine were reduced in MuSCs of old mice. α-KG or glutamine re-established appropriate muscle regeneration of adult conditional Psat1 -/- mice and of old mice. These findings contribute insights into the metabolic role of Psat1 during muscle regeneration and suggest α-KG and glutamine as potential therapeutic interventions to ameliorate muscle regeneration during aging.PMID:38453480 | DOI:10.1101/gad.351428.123

Mechanic evaluation of Wu-Mei-Pill on colitis-associated colorectal cancer: An integrated transcriptomics, metabolomics, and experimental validation study

Thu, 07/03/2024 - 12:00
Phytomedicine. 2024 Mar 2;128:155509. doi: 10.1016/j.phymed.2024.155509. Online ahead of print.ABSTRACTBACKGROUND: Chronic intestinal inflammatory diseases play a crucial role in the onset of colorectal cancer (CRC). Effectively impeding the progression of colitis-associated colorectal cancer (CAC) can be instrumental in hindering CRC development. Wu-Mei-Pill (WMP), a formulation comprising various herbal extracts, is clinically employed for CAC treatment, yet the underlying mechanism of WMP's efficacy in CAC remains unclear. Our study firstly demonstrated the effects and mechanisms of WMP on transcriptional and metabolic levels based on integrated transcriptomics and untargeted metabolomics and relative experimental validations.MATERIALS AND METHODS: A CAC mouse model was established through a single injection of azoxymethane (AOM) followed by intermittent dextran sodium sulfate (DSS) intervention, with subsequent WMP administration. Initially, the therapeutic impact of WMP on the CAC model was assessed by observing survival rate, body weight change, colon length, tumor number, tumor load, and pathological changes in the colon tissue of CAC mice post-WMP intervention. Subsequently, differential genes and metabolites in the colorectal tissue of CAC mice following WMP intervention were identified through transcriptomics and non-targeted metabolomics. Finally, the influence of WMP on the peroxisome proliferator activated receptor (PPAR) pathway, Wnt pathway, and CC motif chemokine ligand 3 (CCL3)/ CC motif chemokine receptor 1 (CCR1) axis in CAC mice was verified through western blot, immunofluorescence, and ELISA based on the results of transcriptomics and non-targeted metabolomics.RESULTS: WMP intervention enhanced survival, alleviated body weight loss, shortened colon length, tumor occurrence, and pathological changes in the colorectal tissue of CAC mice, such as glandular damage, tumourigenesis, and inflammatory cell infiltration. Transcriptomic and non-targeted metabolomic results revealed that WMP intervention up-regulated the expression of key regulatory mechanisms of fatty acid oxidation PPAR pathway-related genes (Pparg, Ppara, Cpt1a, and Acadm) and metabolites (L-carnitine and L-palmitoylcarnitine). Additionally, it down-regulated Wnt pathway-related genes (Wnt3, Axin2, Tcf7, Mmp7, Lgr5, Wnt5a, Fzd6, Wnt7b, Lef1, and Fzd10 etc.) and pro-inflammatory related genes (Il1b, Il6, Il17a, Ccl3, and Ccr1 etc.). Experimental validation demonstrated that WMP up-regulated PPAR pathway-related proteins [PPARγ, PPARα, carnitine palmitoyltransferase 1A (CPT1A), and acyl-CoA dehydrogenase medium chain (ACADM)] in the colorectal tissue of CAC mice. It also down-regulated Wnt pathway-related proteins [β-catenin, T-cell factor (TCF), lymphoid enhancer-binding factor (LEF), and matrix metallopeptidase 7 (MMP7)], inhibited the nuclear translocation of the key transcription factor β-catenin in the Wnt pathway, and suppressed epithelial-to-mesenchymal transition (EMT) activation induced by the Wnt pathway (up-regulated E-cadherin and down-regulated Vimentin). Furthermore, WMP intervention reduced pro-inflammatory factors [interleukin (IL)-6, IL-1β, and IL-17A] and decreased CCL3/CCR1 axis factors, including CCL3 protein levels and diminished F4/80+CCR1+ positive expressed cells.CONCLUSION: WMP significantly inhibits CAC tumorigenesis by up-regulating PPARα-mediated fatty acid oxidation, inhibiting the Wnt signaling pathway-mediated EMT, and suppressing CCL3/CCR1-mediated inflammatory responses.PMID:38452403 | DOI:10.1016/j.phymed.2024.155509

Metabolomics and Molecular Networking-Guided Screening of Bacillus-Derived Bioactive Compounds Against a Highly Lethal Vibrio Species

Thu, 07/03/2024 - 12:00
Anal Chem. 2024 Mar 7. doi: 10.1021/acs.analchem.3c02958. Online ahead of print.ABSTRACTMicroorganisms are important sources of bioactive natural products. However, the complexity of microbial metabolites and the low abundance of active compounds render the isolation and purification process laborious and inefficient. During our search for active substances capable of inhibiting the newly discovered highly lethal Vibrio strain vp-HL, we found that the fermentation broth of multiple Bacillus strains exhibited antibacterial activity. However, the substances responsible for the activity remained unclear. Metabolomics, molecular networking (MN), and the Structural similarity Network Annotation Platform for Mass Spectrometry (SNAP-MS) were employed in conjunction with bioactivity screening to predict the antibacterial compounds from Bacillus strains. The analysis of fractions, and their isolation, NMR-based annotation, and bioactivity evaluation of an amicoumacin compound partially confirmed the prediction from these statistical analyses. This work presents the potential of marine Bacillus in producing active substances against Vibrio species. Additionally, it highlighted the significance and feasibility of metabolomics and MN in the dereplication of compounds and the determination of isolation targets.PMID:38452345 | DOI:10.1021/acs.analchem.3c02958

Integrative multi-modal metabolomics to early predict cognitive decline among Amyloid positive community-dwelling older adults

Thu, 07/03/2024 - 12:00
J Gerontol A Biol Sci Med Sci. 2024 Mar 7:glae077. doi: 10.1093/gerona/glae077. Online ahead of print.ABSTRACTAlzheimer's disease is strongly linked to metabolic abnormalities. We aimed to distinguish amyloid-positive people who progressed to cognitive decline from those who remained cognitively intact. We performed untargeted metabolomics of blood samples from amyloid-positive individuals, before any sign of cognitive decline, to distinguish individuals who progressed to cognitive decline from those who remained cognitively intact. A plasma-derived metabolite signature was developed from Supercritical Fluid chromatography coupled with high-resolution mass spectrometry (SFC-HRMS) and nuclear magnetic resonance (NMR) metabolomics. The two metabolomics datasets were analyzed by Data Integration Analysis for Biomarker discovery using Latent approaches for Omics studies (DIABLO), to identify a minimum set of metabolites that could describe cognitive decline status. NMR or SFC-HRMS data alone cannot predict cognitive decline. However, among the 320 metabolites identified, a statistical method that integrated the two datasets enabled identification of a minimal signature of 9 metabolites (3-hydroxybutyrate, citrate, succinate, acetone, methionine, glucose, serine, sphingomyelin d18:1/C26:0 and triglyceride C48:3) with a statistically significant ability to predict cognitive decline more than 3 years before decline. This metabolic fingerprint obtained during this exploratory study may help to predict amyloid-positive individuals who will develop cognitive decline. Due to the high prevalence of brain amyloid-positivity in older adults, identifying adults who will have cognitive decline will enable the development of personalized and early interventions.PMID:38452244 | DOI:10.1093/gerona/glae077

Differentially disrupted spinal cord and muscle energy metabolism in spinal and bulbar muscular atrophy

Thu, 07/03/2024 - 12:00
JCI Insight. 2024 Mar 5:e178048. doi: 10.1172/jci.insight.178048. Online ahead of print.ABSTRACTPrior studies showed that polyQ-expanded AR is aberrantly acetylated and that deacetylation of the mutant AR by overexpression of NAD+-dependent sirtuin 1 (SIRT1) is protective in cell models of spinal and bulbar muscular atrophy (SBMA). Based on these observations and reduced NAD+ in muscles of SBMA mouse models, we tested the therapeutic potential of NAD+ restoration in vivo by treating post-symptomatic transgenic SBMA mice with the nicotinamide adenine dinucleotide (NAD+) precursor nicotinamide riboside (NR). NR supplementation failed to alter disease progression and had no effect on increasing NAD+ or ATP content in muscle, despite producing a modest increase of NAD+ in the spinal cord of SBMA mice. Metabolite and proteomic profiles of SBMA quadriceps muscles indicated alterations in several important energy-related pathways that utilize NAD+, in addition to the NAD salvage pathway, which is critical for NAD+ regeneration for use in cellular energy production. We also observed decreased mRNA levels of Nmrk2, which encodes a key kinase responsible for NR phosphorylation, allowing its utilization by the NAD salvage pathway. Together these data suggest a model in which NAD+ levels are significantly decreased in muscles of an SBMA mouse model and intransigent to NR supplementation due to decreased levels of Nmrk2.PMID:38452174 | DOI:10.1172/jci.insight.178048

Comparison of Nutritional Diversity in Five Fresh Legumes Using Flavonoids Metabolomics and Postharvest Botrytis cinerea Defense Analysis of Peas Mediated by Sakuranetin

Thu, 07/03/2024 - 12:00
J Agric Food Chem. 2024 Mar 7. doi: 10.1021/acs.jafc.3c08968. Online ahead of print.ABSTRACTLegumes possess several bioactive nutrients, including flavonoids, and the study of the flavonoid profile of legumes is of great significance to human health. Using widely targeted metabolomics, we revealed the flavonoid profiles of five popular fresh legumes: cowpea, soybean, pea, fava bean, and kidney bean. A total of 259 flavonoids were identified, and the flavonoid accumulation patterns of the five legumes were remarkably different. In addition to analyzing common and species-specific flavonoids in the five legumes, we also generalized representative flavonoids of various subclasses. We related these to the health-promoting effects of legumes. Furthermore, legumes' total flavonoid content and antioxidant system activity were also detected. Intriguingly, sakuranetin, the sole flavonoid phytoalexin that can be induced by UV radiation, was detected only in the peas by metabolomics. Meanwhile, we found that UV treatment could significantly increase the sakuranetin content and the postharvest Botrytis cinerea resistance of pea pods. This study provides clues for the target diet, industrial development of legumes, and a new idea for the postharvest preservation of peas.PMID:38452150 | DOI:10.1021/acs.jafc.3c08968

Cis-regulatory polymorphism at fiz ecdysone oxidase contributes to polygenic evolutionary response to malnutrition in Drosophila

Thu, 07/03/2024 - 12:00
PLoS Genet. 2024 Mar 7;20(3):e1011204. doi: 10.1371/journal.pgen.1011204. Online ahead of print.ABSTRACTWe investigate the contribution of a candidate gene, fiz (fezzik), to complex polygenic adaptation to juvenile malnutrition in Drosophila melanogaster. Experimental populations maintained for >250 generations of experimental evolution to a nutritionally poor larval diet (Selected populations) evolved several-fold lower fiz expression compared to unselected Control populations. Here we show that this divergence in fiz expression is mediated by a cis-regulatory polymorphism. This polymorphism, originally sampled from a natural population in Switzerland, is distinct from a second cis-regulatory SNP previously identified in non-African D. melanogaster populations, implying that two independent cis-regulatory variants promoting high fiz expression segregate in non-African populations. Enzymatic analyses of Fiz protein expressed in E. coli demonstrate that it has ecdysone oxidase activity acting on both ecdysone and 20-hydroxyecdysone. Four of five fiz paralogs annotated to ecdysteroid metabolism also show reduced expression in Selected larvae, implying that malnutrition-driven selection favored general downregulation of ecdysone oxidases. Finally, as an independent test of the role of fiz in poor diet adaptation, we show that fiz knockdown by RNAi results in faster larval growth on the poor diet, but at the cost of greatly reduced survival. These results imply that downregulation of fiz in Selected populations was favored by selection on the nutritionally poor diet because of its role in suppressing growth in response to nutrient shortage. However, they suggest that fiz downregulation is only adaptive in combination with other changes evolved by Selected populations, which ensure that the organism can sustain the faster growth promoted by fiz downregulation.PMID:38452112 | DOI:10.1371/journal.pgen.1011204

Rice-Magnaporthe oryzae interactions in resistant and susceptible rice cultivars under panicle blast infection based on defense-related enzyme activities and metabolomics

Thu, 07/03/2024 - 12:00
PLoS One. 2024 Mar 7;19(3):e0299999. doi: 10.1371/journal.pone.0299999. eCollection 2024.ABSTRACTRice blast, caused by rice blast fungus (Magnaporthe oryzae), is a global threat to food security, with up to 50% yield losses. Panicle blast is a severe form of rice blast, and disease responses vary between cultivars with different genotypes. Reactive oxygen species (ROS)-mediated signaling reactions and the phenylpropanoid pathway are important defense mechanisms involved in recognizing and resisting against fungal infection. To understand rice-M. oryzae interactions in resistant and susceptible cultivars, we determined dynamic changes in the activities of five defense-related enzymes in resistant cultivar jingsui 18 and susceptible cultivar jinyuan 899 infected with M. oryzae from 4 to 25 days after infection. We then performed untargeted metabolomics analyses to profile the metabolomes of the cultivars under infected and non-infected conditions. Dynamic changes in the activities of five defense-related enzymes were closely related to panicle blast resistance in rice. Metabolome data analysis identified 634 differentially accumulated metabolites (DAMs) between resistant and susceptible cultivars following infection, potentially explaining differences in disease response between varieties. The most enriched DAMs were associated with lipids and lipid-like molecules, phenylpropanoids and polyketides, organoheterocyclic compounds, organic acids and derivatives, and lignans, neolignans, and related compounds. Multiple metabolic pathways are involved in resistance to panicle blast in rice, including biosynthesis of other secondary metabolites, amino acid metabolism, lipid metabolism, phenylpropanoid biosynthesis, arachidonic acid metabolism, arginine biosynthesis, tyrosine metabolism, tryptophan metabolism, tyrosine and tryptophan biosynthesis, lysine biosynthesis, and oxidative phosphorylation.PMID:38451992 | DOI:10.1371/journal.pone.0299999

tRNA epitranscriptome determines pathogenicity of the opportunistic pathogen <em>Pseudomonas aeruginosa</em>

Thu, 07/03/2024 - 12:00
Proc Natl Acad Sci U S A. 2024 Mar 12;121(11):e2312874121. doi: 10.1073/pnas.2312874121. Epub 2024 Mar 7.ABSTRACTThe success of bacterial pathogens depends on the coordinated expression of virulence determinants. Regulatory circuits that drive pathogenesis are complex, multilayered, and incompletely understood. Here, we reveal that alterations in tRNA modifications define pathogenic phenotypes in the opportunistic pathogen Pseudomonas aeruginosa. We demonstrate that the enzymatic activity of GidA leads to the introduction of a carboxymethylaminomethyl modification in selected tRNAs. Modifications at the wobble uridine base (cmnm5U34) of the anticodon drives translation of transcripts containing rare codons. Specifically, in P. aeruginosa the presence of GidA-dependent tRNA modifications modulates expression of genes encoding virulence regulators, leading to a cellular proteomic shift toward pathogenic and well-adapted physiological states. Our approach of profiling the consequences of chemical tRNA modifications is general in concept. It provides a paradigm of how environmentally driven tRNA modifications govern gene expression programs and regulate phenotypic outcomes responsible for bacterial adaption to challenging habitats prevailing in the host niche.PMID:38451943 | DOI:10.1073/pnas.2312874121

Targeting tryptophan catabolism in ovarian cancer to attenuate macrophage infiltration and PD-L1 expression

Thu, 07/03/2024 - 12:00
Cancer Res Commun. 2024 Mar 7. doi: 10.1158/2767-9764.CRC-23-0513. Online ahead of print.ABSTRACTHigh grade serous carcinoma (HGSC) of the fallopian tube, ovary and peritoneum is the most common type of ovarian cancer and is predicted to be immunogenic since the presence of tumor-infiltrating lymphocytes conveys a better prognosis. However, the efficacy of immunotherapies has been limited due to the immune-suppressed tumor microenvironment (TME). Tumor metabolism and immune-suppressive metabolites directly affect immune cell function through the depletion of nutrients and activation of immune-suppressive transcriptional programs. Tryptophan (TRP) catabolism is a contributor to HGSC disease progression. Two structurally distinct rate-limiting TRP catabolizing enzymes, Indoleamine 2,3-Dioxygenase 1 (IDO1) and Tryptophan 2,3-Dioxygenase 2 (TDO2), evolved separately to catabolize TRP. IDO1/TDO2 are aberrantly expressed in carcinomas and metabolize TRP into the immune-suppressive metabolite kynurenine (KYN), which can engage the aryl hydrocarbon receptor (AhR) to drive immunosuppressive transcriptional programs. To date, IDO inhibitors tested in clinical trials have had limited efficacy, but those inhibitors did not target TDO2, and we find that HGSC cell lines and clinical outcomes are more dependent on TDO2 than IDO1. To identify inflammatory HGSC cancers with poor prognosis, we stratified patient ascites samples by IL6 status, which correlates with poor prognosis. Metabolomics revealed that IL6 high patient samples had enriched KYN. TDO2 knockdown significantly inhibited HGSC growth and TRP catabolism. The orally available dual IDO1/TDO2 inhibitor, AT-0174, significantly inhibited tumor progression, reduced tumor-associated macrophages, and reduced expression of immune-suppressive proteins on immune and tumor cells. These studies demonstrate the importance of TDO2 and the therapeutic potential of AT-0174 to overcome an immune-suppressed TME.PMID:38451784 | DOI:10.1158/2767-9764.CRC-23-0513

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