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

Overexpression of Brassica napus COMT1 in Arabidopsis heightens UV-B-mediated resistance to Plutella xylostella herbivory

Fri, 28/07/2023 - 12:00
Photochem Photobiol Sci. 2023 Jul 28. doi: 10.1007/s43630-023-00455-9. Online ahead of print.ABSTRACTUV-B radiation regulates numerous morphogenic, biochemical and physiological responses in plants, and can stimulate some responses typically associated with other abiotic and biotic stimuli, including invertebrate herbivory. Removal of UV-B from the growing environment of various plant species has been found to increase their susceptibility to consumption by invertebrate pests, however, to date, little research has been conducted to investigate the effects of UV-B on crop susceptibility to field pests. Here, we report findings from a multi-omic and genetic-based study investigating the mechanisms of UV-B-stimulated resistance of the crop, Brassica napus (oilseed rape), to herbivory from an economically important lepidopteran specialist of the Brassicaceae, Plutella xylostella (diamondback moth). The UV-B photoreceptor, UV RESISTANCE LOCUS 8 (UVR8), was not found to mediate resistance to this pest. RNA-Seq and untargeted metabolomics identified components of the sinapate/lignin biosynthetic pathway that were similarly regulated by UV-B and herbivory. Arabidopsis mutants in genes encoding two enzymes in the sinapate/lignin biosynthetic pathway, CAFFEATE O-METHYLTRANSFERASE 1 (COMT1) and ELICITOR-ACTIVATED GENE 3-2 (ELI3-2), retained UV-B-mediated resistance to P. xylostella herbivory. However, the overexpression of B. napus COMT1 in Arabidopsis further reduced plant susceptibility to P. xylostella herbivory in a UV-B-dependent manner. These findings demonstrate that overexpression of a component of the sinapate/lignin biosynthetic pathway in a member of the Brassicaceae can enhance UV-B-stimulated resistance to herbivory from P. xylostella.PMID:37505444 | DOI:10.1007/s43630-023-00455-9

Serum identification of At-Risk MASH: The Metabolomics-Advanced steatohepatitis fibrosis score (MASEF)

Fri, 28/07/2023 - 12:00
Hepatology. 2023 Jul 24. doi: 10.1097/HEP.0000000000000542. Online ahead of print.ABSTRACTBACKGROUND: Early identification of those with NAFLD activity score ≥ 4 and significant fibrosis (≥F2) or "at-risk MASH" is a priority as these patients are at increased risk for disease progression and may benefit from therapies. We developed and validated a highly specific metabolomics-driven score to identify at-risk MASH.METHODS: We included derivation (n = 790) and validation (n = 565) cohorts from international tertiary centers. Patients underwent laboratory assessment and liver biopsy for MASLD. Based on 12 lipids, body mass index, aspartate aminotransferase, and alanine aminotransferase, the MASEF score was developed to identify at-risk MASH and compared to the FibroScan-AST (FAST) score. We further compared the performance of a FIB-4 + MASEF algorithm to that of FIB-4 + liver stiffness measurements (LSM) by transient elastography (VCTE).RESULTS: The diagnostic performance of the MASEF score showed an area under the receiver-operating characteristic curve, sensitivity, specificity, positive and negative predictive values of 0.76 (95% CI 0.72-0.79), 0.69, 0.74, 0.53, and 0.85 in the derivation cohort, and 0.79 (95% CI 0.75-0.83), 0.78, 0.65, 0.48, and 0.88 in the validation cohort, while FAST performance in the validation cohort was 0.74 (95% CI 0.68-0.79; p = 0.064), 0.58, 0.79, 0.67, and 0.73, respectively. FIB-4 + MASEF showed similar overall performance compared to FIB-4 + LSM by VCTE (p = 0.69) to identify at-risk MASH.CONCLUSION: MASEF is a promising diagnostic tool for the assessment of at-risk MASH. It could be used alternatively to LSM by VCTE in the algorithm that is currently recommended by several guidance publications.PMID:37505221 | DOI:10.1097/HEP.0000000000000542

Maternal voluntary wheel running modulates glucose homeostasis, the gut microbiota and its derived fecal metabolites in offspring

Fri, 28/07/2023 - 12:00
Clin Sci (Lond). 2023 Jul 28:CS20230372. doi: 10.1042/CS20230372. Online ahead of print.ABSTRACTMaternal overnutrition can dramatically increase the susceptibility of offspring to metabolic diseases, whereas maternal exercise may improve glucose metabolism in offspring. However, the underlying mechanism programming the intergenerational effects of maternal exercise on the benefits of glucose metabolism has not been fully elaborated. C57BL/6 female mice were randomly assigned to four subgroups according to a diet and exercise paradigm before and during pregnancy as follows: NC (fed with normal chow diet and sedentary), NCEx (fed with normal chow diet and running), HF (fed with high-fat diet and sedentary), and HFEx (fed with high-fat diet and running). Integrative 16S rDNA sequencing and mass spectrometry-based metabolite profiling were synchronously performed to characterize the effects of maternal exercise on the gut microbiota composition and metabolite alterations in offspring. Maternal exercise, acting as a natural pharmaceutical intervention, prevented deleterious effects on glucose metabolism in offspring. 16S rDNA sequencing revealed remarkable changes in the gut microbiota composition in offspring. Metabolic profiling indicated multiple altered metabolites, which were enriched in butanoate metabolism signaling in offspring. We further found that maternal exercise could mediate gene expression related to intestinal gluconeogenesis in offspring. In conclusion, our study indicated that maternal running significantly improved glucose metabolism in offspring and counteracted the detrimental effects of maternal high-fat feeding before and during pregnancy. We further demonstrated that maternal voluntary wheel running could integratively program the gut microbiota composition and fecal metabolite changes and then regulate butanoate metabolism and mediate intestinal gluconeogenesis in offspring.PMID:37505199 | DOI:10.1042/CS20230372

Comparison of the Effect of Phospholipid Extracts from Salmon and Silver Carp Heads on High-Fat-Diet-Induced Metabolic Syndrome in C57BL/6J Mice

Fri, 28/07/2023 - 12:00
Mar Drugs. 2023 Jul 19;21(7):409. doi: 10.3390/md21070409.ABSTRACTMetabolic syndrome (MetS) is a global health problem, and EPA/DHA-enriched phospholipids (EPA/DHA-PLs) have been found to have positive effects on MetS improvement. Currently, research on EPA/DHA-PL mainly focuses on special and rare seafood, such as phospholipids derived from krill, sea cucumber, squid, and fish roe. However, it has been recently demonstrated that abundant EPA/DHA-PL can also be found in bulk fish and its by-products. Nonetheless, there is still limited research on the biological activities of EPA/DHA-PL derived from these sources. The aim of this study was to investigate the effect of phospholipid extracts from the heads of salmon and silver carp (S-PLE and SC-PLE) on the high-fat-diet-induced MetS in C57/BL mice. After an 8-week intervention, both SC-PLE and S-PLE had a significant ameliorating effect on MetS. Moreover, SC-PLE was more effective than S-PLE in reducing liver inflammation and fasting glucose. Both of the PL extracts were able to regulate the expression of key genes in lipid synthesis, fatty acid β-oxidation, and insulin signaling pathways. Compared with S-PLE, dietary SC-PLE had a greater influence on liver metabolomics. Pathway enrichment analysis showed that the differential metabolites of SC-PLE were mainly involved in arachidonic acid metabolism and glutathione metabolism. The results indicated that the different metabolic regulation methods of S-PLE and SC-PLE could be related to their variant molecular composition in EPA/DHA-PL.PMID:37504940 | DOI:10.3390/md21070409

Genomic and Metabolomic Analysis of the Endophytic Fungus <em>Fusarium</em> sp. VM-40 Isolated from the Medicinal Plant <em>Vinca minor</em>

Fri, 28/07/2023 - 12:00
J Fungi (Basel). 2023 Jun 27;9(7):704. doi: 10.3390/jof9070704.ABSTRACTThe genus Fusarium is well-known to comprise many pathogenic fungi that affect cereal crops worldwide, causing severe damage to agriculture and the economy. In this study, an endophytic fungus designated Fusarium sp. VM-40 was isolated from a healthy specimen of the traditional European medicinal plant Vinca minor. Our morphological characterization and phylogenetic analysis reveal that Fusarium sp. VM-40 is closely related to Fusarium paeoniae, belonging to the F. tricinctum species complex (FTSC), the genomic architecture and secondary metabolite profile of which have not been investigated. Thus, we sequenced the whole genome of Fusarium sp. VM-40 with the new Oxford Nanopore R10.4 flowcells. The assembled genome is 40 Mb in size with a GC content of 47.72%, 15 contigs (≥50,000 bp; N 50~4.3 Mb), and 13,546 protein-coding genes, 691 of which are carbohydrate-active enzyme (CAZyme)-encoding genes. We furthermore predicted a total of 56 biosynthetic gene clusters (BGCs) with antiSMASH, 25 of which showed similarity with known BGCs. In addition, we explored the potential of this fungus to produce secondary metabolites through untargeted metabolomics. Our analyses reveal that this fungus produces structurally diverse secondary metabolites of potential pharmacological relevance (alkaloids, peptides, amides, terpenoids, and quinones). We also employed an epigenetic manipulation method to activate cryptic BGCs, which led to an increased abundance of several known compounds and the identification of several putative new compounds. Taken together, this study provides systematic research on the whole genome sequence, biosynthetic potential, and metabolome of the endophytic fungus Fusarium sp. VM-40.PMID:37504693 | DOI:10.3390/jof9070704

Integration of Physiological, Transcriptomic and Metabolomic Reveals Molecular Mechanism of <em>Paraisaria dubia</em> Response to Zn<sup>2+</sup> Stress

Fri, 28/07/2023 - 12:00
J Fungi (Basel). 2023 Jun 21;9(7):693. doi: 10.3390/jof9070693.ABSTRACTUtilizing mycoremediation is an important direction for managing heavy metal pollution. Zn2+ pollution has gradually become apparent, but there are few reports about its pollution remediation. Here, the Zn2+ remediation potential of Paraisaria dubia, an anamorph of the entomopathogenic fungus Ophiocordyceps gracilis, was explored. There was 60% Zn2+ removed by Paraisaria dubia mycelia from a Zn2+-contaminated medium. To reveal the Zn2+ tolerance mechanism of Paraisaria dubia, transcriptomic and metabolomic were executed. Results showed that Zn2+ caused a series of stress responses, such as energy metabolism inhibition, oxidative stress, antioxidant defense system disruption, autophagy obstruction, and DNA damage. Moreover, metabolomic analyses showed that the biosynthesis of some metabolites was affected against Zn2+ stress. In order to improve the tolerance to Zn2+ stress, the metabolic mechanism of metal ion transport, extracellular polysaccharides (EPS) synthesis, and microcycle conidiation were activated in P. dubia. Remarkably, the formation of microcycle conidiation may be triggered by reactive oxygen species (ROS) and mitogen-activated protein kinase (MAPK) signaling pathways. This study supplemented the gap of the Zn2+ resistance mechanism of Paraisaria dubia and provided a reference for the application of Paraisaria dubia in the bioremediation of heavy metals pollution.PMID:37504682 | DOI:10.3390/jof9070693

Microbiomic and Metabolomic Analyses Unveil the Protective Effect of Saffron in a Mouse Colitis Model

Fri, 28/07/2023 - 12:00
Curr Issues Mol Biol. 2023 Jun 30;45(7):5558-5574. doi: 10.3390/cimb45070351.ABSTRACTDespite the existence of effective drugs used to treat inflammatory bowel disease (IBD), many patients fail to respond or lose response over time. Further, many drugs can carry serious adverse effects, including increased risk of infections and malignancies. Saffron (Crocus sativus) has been reported to have anti-inflammatory properties. Its protective role in IBD and how the microbiome and metabolome play a role has not been explored extensively. We aimed to establish whether saffron treatment modulates the host microbiome and metabolic profile in experimental colitis. Colitis was induced in C57BL/6 mice with 3% DSS and treated with either saffron in a dose of 20 mg/kg body weight or vehicle through daily gavage. On day 10, stool pellets from mice were collected and analyzed to assess saffron's effect on fecal microbiota and metabolites through 16S rRNA sequencing and untargeted primary metabolite analysis. Saffron treatment maintained gut microbiota homeostasis by counter-selecting pro-inflammatory bacteria and maintained Firmicutes/Bacteroides ratio, which was otherwise disturbed by DSS treatment. Several metabolites (uric acid, cholesterol, 2 hydroxyglutaric acid, allantoic acid, 2 hydroxyhexanoic acid) were altered significantly with saffron treatment in DSS-treated mice, and this might play a role in mediating saffron's colitis-mitigating effects. These data demonstrate saffron's therapeutic potential, and its protective role is modulated by gut microbiota, potentially acting through changes in metabolites.PMID:37504267 | DOI:10.3390/cimb45070351

Application of Paper-Based Microfluidic Analytical Devices (µPAD) in Forensic and Clinical Toxicology: A Review

Fri, 28/07/2023 - 12:00
Biosensors (Basel). 2023 Jul 18;13(7):743. doi: 10.3390/bios13070743.ABSTRACTThe need for providing rapid and, possibly, on-the-spot analytical results in the case of intoxication has prompted researchers to develop rapid, sensitive, and cost-effective methods and analytical devices suitable for use in nonspecialized laboratories and at the point of need (PON). In recent years, the technology of paper-based microfluidic analytical devices (μPADs) has undergone rapid development and now provides a feasible, low-cost alternative to traditional rapid tests for detecting harmful compounds. In fact, µPADs have been developed to detect toxic molecules (arsenic, cyanide, ethanol, and nitrite), drugs, and drugs of abuse (benzodiazepines, cathinones, cocaine, fentanyl, ketamine, MDMA, morphine, synthetic cannabinoids, tetrahydrocannabinol, and xylazine), and also psychoactive substances used for drug-facilitated crimes (flunitrazepam, gamma-hydroxybutyric acid (GHB), ketamine, metamizole, midazolam, and scopolamine). The present report critically evaluates the recent developments in paper-based devices, particularly in detection methods, and how these new analytical tools have been tested in forensic and clinical toxicology, also including future perspectives on their application, such as multisensing paper-based devices, microfluidic paper-based separation, and wearable paper-based sensors.PMID:37504142 | DOI:10.3390/bios13070743

Metabolite profiling of Pleurotus ostreatus grown on sisal agro-industrial waste supplemented with cocoa almond tegument and wheat bran

Fri, 28/07/2023 - 12:00
Chem Biodivers. 2023 Jul 28:e202300346. doi: 10.1002/cbdv.202300346. Online ahead of print.ABSTRACTPleurotus ostreatus is an edible fungus with high nutritional value that uses industrial and agricultural lignocellulosic residues as substrates for growth and reproduction. Understanding their growth metabolic dynamics on agro-industrial wastes would help to develop economically viable and eco-friendly biotechnological strategies for food production. Thus, we used UHPLC-MS/MS and GNPS as an innovative approach to investigate the chemical composition of two strains of P. ostreatus, coded as BH (Black Hirataki) and WH (White Hirataki), grown on sisal waste mixture (SW) supplemented with 20% cocoa almond tegument (CAT) or 20% of wheat bran (WB). Metabolite dereplication allowed the identification of 53 metabolites, which included glycerophospholipids, fatty acids, monoacylglycerols, steroids, carbohydrates, amino acids, and flavonoids. This is the first report of the identification of these compounds in P. ostreatus, except for the steroid ergosterol. Most of the metabolites described in this work possess potential biological activities, which support the nutraceutical properties of P. ostreatus. Thus, the results of this study provide essential leads to the understanding of white-rot fungi chemical plasticity aiming at developing alternative biotechnologies strategies for waste recycling.PMID:37503864 | DOI:10.1002/cbdv.202300346

Implication of metabolism in the polarization of tumor-associated-macrophages: the mass spectrometry-based point of view

Fri, 28/07/2023 - 12:00
Front Immunol. 2023 Jul 12;14:1193235. doi: 10.3389/fimmu.2023.1193235. eCollection 2023.ABSTRACTTumor-associated macrophages (TAMs) represent one of the main tumor-infiltrating immune cell types and are generally categorized into either of two functionally contrasting subtypes, namely classical activated M1 macrophages and alternatively activated M2 macrophages. TAMs showed different activation states that can be represent by the two extremes of the complex profile of macrophages biology, the M1-like phenotype (pro-inflammatory activity) and the M2-like phenotype (anti-inflammatory activity). Based on the tumor type, and grades, TAMs can acquire different functions and properties; usually, the M1-like phenotype is typical of early tumor stages and is associated to an anti-tumor activity, while M2-like phenotype has a pro-inflammatory activity and is related to a poor patients' prognosis. The classification of macrophages into M1/M2 groups based on well-defined stimuli does not model the infinitely more complex tissue milieu where macrophages (potentially of different origin) would be exposed to multiple signals in different sequential order. This review aims to summarize the recent mass spectrometry-based (MS-based) metabolomics findings about the modifications of metabolism in TAMs polarization in different tumors. The published data shows that MS-based metabolomics is a promising tool to help better understanding TAMs metabolic phenotypes, although it is still poorly applied for TAMs metabolism. The knowledge of key metabolic alterations in TAMs is an essential step for discovering TAMs polarization novel biomarkers and developing novel therapeutic approaches targeting TAM metabolism to repolarize TAMs towards their anti-tumor phenotype.PMID:37503340 | PMC:PMC10368868 | DOI:10.3389/fimmu.2023.1193235

Metabolic Interactive Nodular Network for Omics (MINNO): Refining and investigating metabolic networks based on empirical metabolomics data

Fri, 28/07/2023 - 12:00
bioRxiv. 2023 Jul 17:2023.07.14.548964. doi: 10.1101/2023.07.14.548964. Preprint.ABSTRACTMetabolomics is a powerful tool for uncovering biochemical diversity in a wide range of organisms, and metabolic network modeling is commonly used to frame results in the context of a broader homeostatic system. However, network modeling of poorly characterized, non-model organisms remains challenging due to gene homology mismatches. To address this challenge, we developed Metabolic Interactive Nodular Network for Omics (MINNO), a web-based mapping tool that takes in empirical metabolomics data to refine metabolic networks for both model and unusual organisms. MINNO allows users to create and modify interactive metabolic pathway visualizations for thousands of organisms, in both individual and multi-species contexts. Herein, we demonstrate an important application of MINNO in elucidating the metabolic networks of understudied species, such as those of the Borrelia genus, which cause Lyme disease and relapsing fever. Using a hybrid genomics-metabolomics modeling approach, we constructed species-specific metabolic networks for three Borrelia species. Using these empirically refined networks, we were able to metabolically differentiate these genetically similar species via their nucleotide and nicotinate metabolic pathways that cannot be predicted from genomic networks. These examples illustrate the use of metabolomics for the empirical refining of genetically constructed networks and show how MINNO can be used to study non-model organisms.PMID:37503268 | PMC:PMC10370097 | DOI:10.1101/2023.07.14.548964

Machine Learning identifies conserved traits that influence lifespan and healthspan responses to dietary restriction

Fri, 28/07/2023 - 12:00
bioRxiv. 2023 Jul 13:2023.07.09.548232. doi: 10.1101/2023.07.09.548232. Preprint.ABSTRACTDietary restriction (DR) is the most robust means to extend lifespan and healthspan across species, but factors such as genetic variation affect how an individual will respond to DR. Additionally, it is unclear how cumulative variations in metabolism and the metabolome influence longevity and health. We utilized metabolomic, phenotypic, and genome-wide data from Drosophila Genetic Reference Panel strains raised under ad libitum and DR conditions to identify factors which influence longevity and health in response to dietary modulation. We found multiple intra-dataset correlations (e.g., metabolites with metabolites) but few inter-dataset correlations (e.g., metabolites with health-related phenotypes). Through random forest modeling across all traits and Mendelian Randomization, we found key translatable traits that influence lifespan or healthspan determination and validated the role of multiple metabolites in regulating lifespan. Through these approaches, we utilized data from flies and humans to elucidate potential therapeutic pathways and metabolomic targets for diet response, lifespan, and healthspan.PMID:37503266 | PMC:PMC10369897 | DOI:10.1101/2023.07.09.548232

Human Cytomegalovirus in breast milk is associated with milk composition, the infant gut microbiome, and infant growth

Fri, 28/07/2023 - 12:00
bioRxiv. 2023 Jul 19:2023.07.19.549370. doi: 10.1101/2023.07.19.549370. Preprint.ABSTRACTHuman cytomegalovirus (CMV) is a highly prevalent herpesvirus that is often transmitted to the neonate via breast milk. Postnatal CMV transmission can have negative health consequences for preterm and immunocompromised infants, but any effects on healthy term infants are thought to be benign. Furthermore, the impact of CMV on the composition of the hundreds of bioactive factors in human milk has not been tested. Here, we utilize a cohort of exclusively breastfeeding full term mother-infant pairs to test for differences in the milk transcriptome and metabolome associated with CMV, and the impact of CMV in breast milk on the infant gut microbiome and infant growth. We find upregulation of the indoleamine 2,3-dioxygenase (IDO) tryptophan-to-kynurenine metabolic pathway in CMV+ milk samples, and that CMV+ milk is associated with decreased Bifidobacterium in the infant gut. Our data indicate a complex relationship between milk CMV, milk kynurenine, and infant growth; with kynurenine positively correlated, and CMV viral load negatively correlated, with infant weight-for-length at 1 month of age. These results suggest CMV transmission, CMV-related changes in milk composition, or both may be modulators of full term infant development.PMID:37503212 | PMC:PMC10370112 | DOI:10.1101/2023.07.19.549370

Metabolomic Profiles of Sleep-Disordered Breathing are Associated with Hypertension and Diabetes Mellitus Development: the HCHS/SOL

Fri, 28/07/2023 - 12:00
Res Sq. 2023 Jul 21:rs.3.rs-3171622. doi: 10.21203/rs.3.rs-3171622/v1. Preprint.ABSTRACTSleep-disordered breathing (SDB) is a prevalent disorder characterized by recurrent episodic upper airway obstruction. In a dataset from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), we applied principal component analysis (PCA) on seven measures characterizing SDB-associated respiratory events. We estimated the association of the top two SDB PCs with serum levels of 617 metabolites, in both single-metabolite analysis, and a joint, penalized regression analysis using the least absolute shrinkage and selection operator (LASSO). Discovery analysis included n = 3,299 HCHS/SOL individuals; associations were validated in a separate dataset of n = 1,522 HCHS/SOL individuals. Seven metabolite associations with SDB PCs were discovered and replicated. Metabolite risk scores (MRSs) developed based on LASSO association results and representing metabolite signatures associated with the two SDB PCs were associated with 6-year incident hypertension and incident diabetes. MRSs have the potential to serve as biomarkers for SDB, guiding risk stratification and treatment decisions.PMID:37503089 | PMC:PMC10371150 | DOI:10.21203/rs.3.rs-3171622/v1

Mitochondrial proteostasis mediated by CRL5 <sup>Ozz</sup> and Alix maintains skeletal muscle function

Fri, 28/07/2023 - 12:00
bioRxiv. 2023 Jul 11:2023.07.11.548601. doi: 10.1101/2023.07.11.548601. Preprint.ABSTRACTHigh energy-demanding tissues, such as skeletal muscle, require mitochondrial proteostasis to function properly. Two quality-control mechanisms, the ubiquitin proteasome system (UPS) and the release of mitochondria-derived vesicles, safeguard mitochondrial proteostasis. However, whether these processes interact is unknown. Here we show that the E3 ligase CRL5 Ozz , a member of the UPS, and its substrate Alix control the mitochondrial concentration of Slc25A4, a solute carrier that is essential for ATP production. The mitochondria in Ozz -/- or Alix -/- skeletal muscle share overt morphologic alterations (they are supernumerary, swollen, and dysmorphic) and have abnormal metabolomic profiles. We found that CRL5 Ozz ubiquitinates Slc25A4 and promotes its proteasomal degradation, while Alix facilitates SLC25A4 loading into exosomes destined for lysosomal destruction. The loss of Ozz or Alix offsets steady-state levels of Slc25A4, which disturbs mitochondrial metabolism and alters muscle fiber composition. These findings reveal hitherto unknown regulatory functions of Ozz and Alix in mitochondrial proteostasis.PMID:37503076 | PMC:PMC10369959 | DOI:10.1101/2023.07.11.548601

3-hydroxykynurenine is a ROS-inducing cytotoxic tryptophan metabolite that disrupts the TCA cycle

Fri, 28/07/2023 - 12:00
bioRxiv. 2023 Jul 10:2023.07.10.548411. doi: 10.1101/2023.07.10.548411. Preprint.ABSTRACTTryptophan is an essential amino acid that is extensively characterized as a regulator of cellular function through its metabolism by indoleamine 2,3-deoxygenase (IDO) into the kynurenine pathway. However, despite decades of research on tryptophan metabolism, the metabolic regulatory roles of it and its metabolites are not well understood. To address this, we performed an activity metabolomics screen of tryptophan and most of its known metabolites in cell culture. We discovered that treatment of human colon cancer cells (HCT116) with 3-hydroxykynurenine (3-HK), a metabolite of kynurenine, potently disrupted TCA cycle function. Citrate and aconitate levels were increased, while isocitrate and all downstream TCA metabolites were decreased, suggesting decreased aconitase function. We hypothesized that 3HK or one of its metabolites increased reactive oxygen species (ROS) and inhibited aconitase activity. Accordingly, we observed almost complete depletion of reduced glutathione and a decrease in total glutathione levels. We observed a dose-dependent decrease in cell viability after 48 hours of 3HK treatment. These data suggest that raising the intracellular levels of 3HK could be sufficient to induce ROS-mediated apoptosis. We modulated the intracellular levels of 3HK by combined induction of IDO and knockdown of kynureninase (KYNU) in HCT116 cells. Cell viability decreased significantly after 48 hours of KYNU knockdown compared to controls, which was accompanied by increased ROS production and Annexin V staining revealing apoptosis. Finally, we identify xanthommatin production from 3-HK as a candidate radical-producing, cytotoxic mechanism. Our work indicates that KYNU may be a target for disrupting tryptophan metabolism. Interestingly, many cancers exhibit overexpression of IDO, providing a cancer-specific metabolic vulnerability that could be exploited by KYNU inhibition.PMID:37502990 | PMC:PMC10369892 | DOI:10.1101/2023.07.10.548411

Thermoneutral housing promotes hepatic steatosis in standard diet-fed C57BL/6N mice, with a less pronounced effect on NAFLD progression upon high-fat feeding

Fri, 28/07/2023 - 12:00
Front Endocrinol (Lausanne). 2023 Jul 12;14:1205703. doi: 10.3389/fendo.2023.1205703. eCollection 2023.ABSTRACTINTRODUCTION: Non-alcoholic fatty liver disease (NAFLD) can progress to more severe stages, such as steatohepatitis and fibrosis. Thermoneutral housing together with high-fat diet promoted NAFLD progression in C57BL/6J mice. Due to possible differences in steatohepatitis development between different C57BL/6 substrains, we examined how thermoneutrality affects NAFLD progression in C57BL/6N mice.METHODS: Male mice were fed standard or high-fat diet for 24 weeks and housed under standard (22°C) or thermoneutral (30°C) conditions.RESULTS: High-fat feeding promoted weight gain and hepatic steatosis, but the effect of thermoneutral environment was not evident. Liver expression of inflammatory markers was increased, with a modest and inconsistent effect of thermoneutral housing; however, histological scores of inflammation and fibrosis were generally low (<1.0), regardless of ambient temperature. In standard diet-fed mice, thermoneutrality increased weight gain, adiposity, and hepatic steatosis, accompanied by elevated de novo lipogenesis and changes in liver metabolome characterized by complex decreases in phospholipids and metabolites involved in urea cycle and oxidative stress defense.CONCLUSION: Thermoneutrality appears to promote NAFLD-associated phenotypes depending on the C57BL/6 substrain and/or the amount of dietary fat.PMID:37501785 | PMC:PMC10369058 | DOI:10.3389/fendo.2023.1205703

Mitochondria-related genes and metabolic profiles of innate and adaptive immune cells in primary Sjögren's syndrome

Thu, 27/07/2023 - 12:00
Front Immunol. 2023 Jul 11;14:1156774. doi: 10.3389/fimmu.2023.1156774. eCollection 2023.ABSTRACTBACKGROUND: Primary Sjogren's syndrome (pSS) is a prototypical systemic autoimmune disease characterised by lymphocyte infiltration and immune-complex deposition in multiple organs. The specific distribution of immune cell populations and their relationship with mitochondria remain unknown.METHODS: Histological analysis was performed to assess the specific distribution of innate and adaptive immune cell populations in labial salivary gland (LSG) samples from 30 patients with pSS and 13 patients with non-pSS. The ultrastructural morphometric features of mitochondria within immune cells were observed under the transmission electron microscope (TEM). RNA sequencing was performed on LSG samples from 40 patients with pSS and 7 non-pSS patients. The Single-sample Gene Set Enrichment Analysis (ssGSEA), ESTIMATE, and CIBERSORT algorithms and Pearson correlation coefficients were used to examine the relationship between mitochondria-related genes and immune infiltration. Weighted Gene Co-expression Network Analysis (WGCNA) was used to identify the mitochondria-specific genes and the related pathways based on the immune cell types.RESULTS: HE staining revealed a massive infiltration of plasma cells with abundant immunoglobulin protein distributed around phenotypically normal-appearing acinar and ductal tissues of patients with pSS. Immunohistochemical analyses revealed that innate immune cells (macrophages, eosinophils and NK cells) were distributed throughout the glandular tissue. Dominant adaptive immune cell infiltration composed of B cells, CD4+T cells and CD8+ T cells or ectopic lymphoid follicle-like structures were observed in the LSGs of patients with pSS. TEM validated the swelling of mitochondria with disorganised cristae in some lymphocytes that had invaded the glandular tissue. Subsequently, bioinformatic analysis revealed that innate and adaptive immune cells were associated with different mitochondrial metabolism pathways. Mitochondrial electron transport and respiratory chain complexes in the glandular microenvironment were positively correlated with innate immune cells, whereas amino acid and nucleic acid metabolism were negatively correlated with adaptive immune cells. In addition, mitochondrial biogenesis and mitochondrial apoptosis in the glandular microenvironment were closely associated with adaptive immune cells.CONCLUSION: Innate and adaptive immune cells have distinct distribution profiles in the salivary gland tissues of patients with pSS and are associated with different mitochondrial metabolic pathways, which may contribute to disease progression.PMID:37497211 | PMC:PMC10366690 | DOI:10.3389/fimmu.2023.1156774

Metabolic systems approaches update molecular insights of clinical phenotypes and cardiovascular risk in patients with homozygous familial hypercholesterolemia

Thu, 27/07/2023 - 12:00
BMC Med. 2023 Jul 27;21(1):275. doi: 10.1186/s12916-023-02967-8.ABSTRACTBACKGROUND: Homozygous familial hypercholesterolemia (HoFH) is an orphan metabolic disease characterized by extremely elevated low-density lipoprotein cholesterol (LDL-C), xanthomas, aortic stenosis, and premature atherosclerotic cardiovascular disease (ASCVD). In addition to LDL-C, studies in experimental models and small clinical populations have suggested that other types of metabolic molecules might also be risk factors responsible for cardiovascular complications in HoFH, but definitive evidence from large-scale human studies is still lacking. Herein, we aimed to comprehensively characterize the metabolic features and risk factors of human HoFH by using metabolic systems strategies.METHODS: Two independent multi-center cohorts with a total of 868 individuals were included in the cross-sectional study. First, comprehensive serum metabolome/lipidome-wide analyses were employed to identify the metabolomic patterns for differentiating HoFH patients (n = 184) from heterozygous FH (HeFH, n = 376) and non-FH (n = 100) subjects in the discovery cohort. Then, the metabolomic patterns were verified in the validation cohort with 48 HoFH patients, 110 HeFH patients, and 50 non-FH individuals. Subsequently, correlation/regression analyses were performed to investigate the associations of clinical/metabolic alterations with typical phenotypes of HoFH. In the prospective study, a total of 84 HoFH patients with available follow-up were enrolled from the discovery cohort. Targeted metabolomics, deep proteomics, and random forest approaches were performed to investigate the ASCVD-associated biomarkers in HoFH patients.RESULTS: Beyond LDL-C, various bioactive metabolites in multiple pathways were discovered and validated for differentiating HoFH from HoFH and non-FH. Our results demonstrated that the inflammation and oxidative stress-related metabolites in the pathways of arachidonic acid and lipoprotein(a) metabolism were independently associated with the prevalence of corneal arcus, xanthomas, and supravalvular/valvular aortic stenosis in HoFH patients. Our results also identified a small marker panel consisting of high-density lipoprotein cholesterol, lipoprotein(a), apolipoprotein A1, and eight proinflammatory and proatherogenic metabolites in the pathways of arachidonic acid, phospholipid, carnitine, and sphingolipid metabolism that exhibited significant performances on predicting first ASCVD events in HoFH patients.CONCLUSIONS: Our findings demonstrate that human HoFH is associated with a variety of metabolic abnormalities and is more complex than previously known. Furthermore, this study provides additional metabolic alterations that hold promise as residual risk factors in HoFH population.PMID:37501168 | DOI:10.1186/s12916-023-02967-8

Metabolic-GWAS provides insights into genetic architecture of seed metabolome in buckwheat

Thu, 27/07/2023 - 12:00
BMC Plant Biol. 2023 Jul 28;23(1):373. doi: 10.1186/s12870-023-04381-x.ABSTRACTBACKGROUND: Buckwheat (Fagopyrum spp.), belonging to the Polygonaceae family, is an ancient pseudo-cereal with high nutritional and nutraceutical properties. Buckwheat proteins are gluten-free and show balanced amino acid and micronutrient profiles, with higher content of health-promoting bioactive flavonoids that make it a golden crop of the future. Plant metabolome is increasingly gaining importance as a crucial component to understand the connection between plant physiology and environment and as a potential link between the genome and phenome. However, the genetic architecture governing the metabolome and thus, the phenome is not well understood. Here, we aim to obtain a deeper insight into the genetic architecture of seed metabolome in buckwheat by integrating high throughput metabolomics and genotyping-by-sequencing applying an array of bioinformatics tools for data analysis.RESULTS: High throughput metabolomic analysis identified 24 metabolites in seed endosperm of 130 diverse buckwheat genotypes. The genotyping-by-sequencing (GBS) of these genotypes revealed 3,728,028 SNPs. The Genome Association and Prediction Integrated Tool (GAPIT) assisted in the identification of 27 SNPs/QTLs linked to 18 metabolites. Candidate genes were identified near 100 Kb of QTLs, providing insights into several metabolic and biosynthetic pathways.CONCLUSIONS: We established the metabolome inventory of 130 germplasm lines of buckwheat, identified QTLs through marker trait association and positions of potential candidate genes. This will pave the way for future dissection of complex economic traits in buckwheat.PMID:37501129 | DOI:10.1186/s12870-023-04381-x

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