Systems Biology

Defined synthetic microbial communities colonize and benefit field-grown sorghum

Wed, 2024-07-10 06:00

ISME J. 2024 Jul 10:wrae126. doi: 10.1093/ismejo/wrae126. Online ahead of print.

ABSTRACT

The rhizosphere constitutes a dynamic interface between plant hosts and their associated microbial communities. Despite the acknowledged potential for enhancing plant fitness by manipulating the rhizosphere, the engineering of the rhizosphere microbiome through inoculation has posed significant challenges. These challenges are thought to arise from the competitive microbial ecosystem where introduced microbes must survive, and the absence of adaptation to the specific metabolic and environmental demands of the rhizosphere. Here, we engineered a synthetic rhizosphere community (SRC1) with the anticipation that it would exhibit a selective advantage in colonizing the host Sorghum bicolor, thereby potentially fostering its growth. SRC1 was assembled from bacterial isolates identified either for their potential role in community cohesion through network analysis or for their ability to benefit from host-specific exudate compounds. The growth performance of SRC1 was assessed in vitro on solid media, in planta under gnotobiotic laboratory conditions, and in the field. Our findings reveal that SRC1 cohesion is most robust when cultivated in the presence of the plant host under laboratory conditions, with lineages being lost from the community when grown either in vitro or in a native field setting. We establish that SRC1 effectively promotes the growth of both above- and below-ground plant phenotypes in both laboratory and native field contexts. Furthermore, in laboratory conditions, these growth enhancements correlate with the transcriptional dampening of lignin biosynthesis in the host. Collectively, these results underscore the potential utility of synthetic microbial communities for modulating crop performance in controlled and native environments alike.

PMID:38984785 | DOI:10.1093/ismejo/wrae126

Categories: Literature Watch

Cell wall-mediated maternal control of apical-basal patterning of the kelp Undaria pinnatifida

Wed, 2024-07-10 06:00

New Phytol. 2024 Jul 10. doi: 10.1111/nph.19953. Online ahead of print.

ABSTRACT

The role of maternal tissue in embryogenesis remains enigmatic in many complex organisms. Here, we investigate the contribution of maternal tissue to apical-basal patterning in the kelp embryo. Focussing on Undaria pinnatifida, we studied the effects of detachment from the maternal tissue using microsurgery, staining of cell wall modifications, morphometric measurements, flow cytometry, genotyping and a modified kelp fertilisation protocol synchronising kelp embryogenesis. Detached embryos are rounder and often show aberrant morphologies. When a part of the oogonial cell wall remains attached to the zygote, the apical-basal patterning is rescued. Furthermore, the absence of contact with maternal tissue increases parthenogenesis, highlighting the critical role of maternal signals in the initial stages of development. These results show a key role for the connection to the maternal oogonial cell wall in apical-basal patterning in kelps. This observation is reminiscent of another brown alga, Fucus, where the cell wall directs the cell fate. Our findings suggest a conserved mechanism across phylogenetically distant oogamous lineages, where localised secretion of sulphated F2 fucans mediates the establishment of the apical-basal polarity. In this model, the maternal oogonial cell wall mediates basal cell fate determination by providing an extrinsic patterning cue to the future kelp embryo.

PMID:38984686 | DOI:10.1111/nph.19953

Categories: Literature Watch

Analytical code sharing practices in biomedical research

Wed, 2024-07-10 06:00

PeerJ Comput Sci. 2024 Jun 28;10:e2066. doi: 10.7717/peerj-cs.2066. eCollection 2024.

ABSTRACT

Data-driven computational analysis is becoming increasingly important in biomedical research, as the amount of data being generated continues to grow. However, the lack of practices of sharing research outputs, such as data, source code and methods, affects transparency and reproducibility of studies, which are critical to the advancement of science. Many published studies are not reproducible due to insufficient documentation, code, and data being shared. We conducted a comprehensive analysis of 453 manuscripts published between 2016-2021 and found that 50.1% of them fail to share the analytical code. Even among those that did disclose their code, a vast majority failed to offer additional research outputs, such as data. Furthermore, only one in ten articles organized their code in a structured and reproducible manner. We discovered a significant association between the presence of code availability statements and increased code availability. Additionally, a greater proportion of studies conducting secondary analyses were inclined to share their code compared to those conducting primary analyses. In light of our findings, we propose raising awareness of code sharing practices and taking immediate steps to enhance code availability to improve reproducibility in biomedical research. By increasing transparency and reproducibility, we can promote scientific rigor, encourage collaboration, and accelerate scientific discoveries. We must prioritize open science practices, including sharing code, data, and other research products, to ensure that biomedical research can be replicated and built upon by others in the scientific community.

PMID:38983240 | PMC:PMC11232620 | DOI:10.7717/peerj-cs.2066

Categories: Literature Watch

A novel copy number variant in the murine Cdh23 gene gives rise to profound deafness and vestibular dysfunction

Tue, 2024-07-09 06:00

Hum Mol Genet. 2024 Jul 9:ddae095. doi: 10.1093/hmg/ddae095. Online ahead of print.

ABSTRACT

Hearing loss is the most common congenital sensory deficit worldwide and exhibits high genetic heterogeneity, making molecular diagnoses elusive for most individuals. Detecting novel mutations that contribute to hearing loss is crucial to providing accurate personalized diagnoses, tailored interventions, and improving prognosis. Copy number variants (CNVs) are structural mutations that are understudied, potential contributors to hearing loss. Here, we present the Abnormal Wobbly Gait (AWG) mouse, the first documented mutant exhibiting waltzer-like locomotor dysfunction, hyperactivity, circling behaviour, and profound deafness caused by a spontaneous CNV deletion in cadherin 23 (Cdh23). We were unable to identify the causative mutation through a conventional whole-genome sequencing (WGS) and variant detection pipeline, but instead found a linked variant in hexokinase 1 (Hk1) that was insufficient to recapitulate the AWG phenotype when introduced into C57BL/6J mice using CRISPR-Cas9. Investigating nearby deafness-associated genes revealed a pronounced downregulation of Cdh23 mRNA and a complete absence of full-length CDH23 protein, which is critical for the development and maintenance of inner ear hair cells, in whole head extracts from AWG neonates. Manual inspection of WGS read depth plots of the Cdh23 locus revealed a putative 10.4 kb genomic deletion of exons 11 and 12 that was validated by PCR and Sanger sequencing. This study underscores the imperative to refine variant detection strategies to permit identification of pathogenic CNVs easily missed by conventional variant calling to enhance diagnostic precision and ultimately improve clinical outcomes for individuals with genetically heterogenous disorders such as hearing loss.

PMID:38981620 | DOI:10.1093/hmg/ddae095

Categories: Literature Watch

The unreasonable effectiveness of equilibrium gene regulation through the cell cycle

Tue, 2024-07-09 06:00

Cell Syst. 2024 Jul 3:S2405-4712(24)00178-9. doi: 10.1016/j.cels.2024.06.002. Online ahead of print.

ABSTRACT

Systems like the prototypical lac operon can reliably hold repression of transcription upon DNA replication across cell cycles with just 10 repressor molecules per cell and behave as if they were at equilibrium. The origin of this phenomenology is still an unresolved question. Here, we develop a general theory to analyze strong perturbations in quasi-equilibrium systems and use it to quantify the effects of DNA replication in gene regulation. We find a scaling law linking actual with predicted equilibrium transcription via a single kinetic parameter. We show that even the lac operon functions beyond the physical limits of naive regulation through compensatory mechanisms that suppress non-equilibrium effects. Synthetic systems without adjuvant activators, such as the cAMP receptor protein (CRP), lack this reliability. Our results provide a rationale for the function of CRP, beyond just being a tunable activator, as a mitigator of cell cycle perturbations.

PMID:38981487 | DOI:10.1016/j.cels.2024.06.002

Categories: Literature Watch

Directly selecting cell-type marker genes for single-cell clustering analyses

Tue, 2024-07-09 06:00

Cell Rep Methods. 2024 Jul 2:100810. doi: 10.1016/j.crmeth.2024.100810. Online ahead of print.

ABSTRACT

In single-cell RNA sequencing (scRNA-seq) studies, cell types and their marker genes are often identified by clustering and differentially expressed gene (DEG) analysis. A common practice is to select genes using surrogate criteria such as variance and deviance, then cluster them using selected genes and detect markers by DEG analysis assuming known cell types. The surrogate criteria can miss important genes or select unimportant genes, while DEG analysis has the selection-bias problem. We present Festem, a statistical method for the direct selection of cell-type markers for downstream clustering. Festem distinguishes marker genes with heterogeneous distribution across cells that are cluster informative. Simulation and scRNA-seq applications demonstrate that Festem can sensitively select markers with high precision and enables the identification of cell types often missed by other methods. In a large intrahepatic cholangiocarcinoma dataset, we identify diverse CD8+ T cell types and potential prognostic marker genes.

PMID:38981475 | DOI:10.1016/j.crmeth.2024.100810

Categories: Literature Watch

Cross-attention enables deep learning on limited omics-imaging-clinical data of 130 lung cancer patients

Tue, 2024-07-09 06:00

Cell Rep Methods. 2024 Jul 5:100817. doi: 10.1016/j.crmeth.2024.100817. Online ahead of print.

ABSTRACT

Deep-learning tools that extract prognostic factors derived from multi-omics data have recently contributed to individualized predictions of survival outcomes. However, the limited size of integrated omics-imaging-clinical datasets poses challenges. Here, we propose two biologically interpretable and robust deep-learning architectures for survival prediction of non-small cell lung cancer (NSCLC) patients, learning simultaneously from computed tomography (CT) scan images, gene expression data, and clinical information. The proposed models integrate patient-specific clinical, transcriptomic, and imaging data and incorporate Kyoto Encyclopedia of Genes and Genomes (KEGG) and Reactome pathway information, adding biological knowledge within the learning process to extract prognostic gene biomarkers and molecular pathways. While both models accurately stratify patients in high- and low-risk groups when trained on a dataset of only 130 patients, introducing a cross-attention mechanism in a sparse autoencoder significantly improves the performance, highlighting tumor regions and NSCLC-related genes as potential biomarkers and thus offering a significant methodological advancement when learning from small imaging-omics-clinical samples.

PMID:38981473 | DOI:10.1016/j.crmeth.2024.100817

Categories: Literature Watch

Mapping the influence of hydrocarbons mixture on molecular mechanisms, involved in breast and lung neoplasms: in silico toxicogenomic data-mining

Tue, 2024-07-09 06:00

Genes Environ. 2024 Jul 9;46(1):15. doi: 10.1186/s41021-024-00310-y.

ABSTRACT

BACKGROUND: Exposure to chemical mixtures inherent in air pollution, has been shown to be associated with the risk of breast and lung cancers. However, studies on the molecular mechanisms of exposure to a mixture of these pollutants, such as hydrocarbons, in the development of breast and lung cancers are scarce. We utilized in silico toxicogenomic analysis to elucidate the molecular pathways linked to both cancers that are influenced by exposure to a mixture of selected hydrocarbons. The Comparative Toxicogenomics Database and Cytoscape software were used for data mining and visualization.

RESULTS: Twenty-five hydrocarbons, common in air pollution with carcinogenicity classification of 1 A/B or 2 (known/presumed or suspected human carcinogen), were divided into three groups: alkanes and alkenes, halogenated hydrocarbons, and polyaromatic hydrocarbons. The in silico data-mining revealed 87 and 44 genes commonly interacted with most of the investigated hydrocarbons are linked to breast and lung cancer, respectively. The dominant interactions among the common genes are co-expression, physical interaction, genetic interaction, co-localization, and interaction in shared protein domains. Among these genes, only 16 are common in the development of both cancers. Benzo(a)pyrene and tetrachlorodibenzodioxin interacted with all 16 genes. The molecular pathways potentially affected by the investigated hydrocarbons include aryl hydrocarbon receptor, chemical carcinogenesis, ferroptosis, fluid shear stress and atherosclerosis, interleukin 17 signaling pathway, lipid and atherosclerosis, NRF2 pathway, and oxidative stress response.

CONCLUSIONS: Within the inherent limitations of in silico toxicogenomics tools, we elucidated the molecular pathways associated with breast and lung cancer development potentially affected by hydrocarbons mixture. Our findings indicate adaptive responses to oxidative stress and inflammatory damages are instrumental in the development of both cancers. Additionally, ferroptosis-a non-apoptotic programmed cell death driven by lipid peroxidation and iron homeostasis-was identified as a new player in these responses. Finally, AHR potential involvement in modulating IL-8, a critical gene that mediates breast cancer invasion and metastasis to the lungs, was also highlighted. A deeper understanding of the interplay between genes associated with these pathways, and other survival signaling pathways identified in this study, will provide invaluable knowledge in assessing the risk of inhalation exposure to hydrocarbons mixture. The findings offer insights into future in vivo and in vitro laboratory investigations that focus on inhalation exposure to the hydrocarbons mixture.

PMID:38982523 | DOI:10.1186/s41021-024-00310-y

Categories: Literature Watch

Readiness for advance care planning and related factors in the general population: a cross sectional study in Iran

Tue, 2024-07-09 06:00

BMC Palliat Care. 2024 Jul 9;23(1):167. doi: 10.1186/s12904-024-01496-2.

ABSTRACT

CONTEXT: Advance Care Planning (ACP), as a process for expressing and recording patients' preferences about end-of-life care, has received increasing attention in recent years. However, implementing ACP has been challenging in Iran.

OBJECTIVES: To assess the readiness for advance care planning and related factors in the general population of Iran.

METHODS: This cross-sectional study was conducted on the general population of Iran in 2022. The data was collected using demographic information questionnaire and The RACP Scale. The purpose and methodology of the research was explained to all participants, and upon their agreement an informed consent was obtained. Participants were invited to fill out the questionnaires wherever is more convenient for them, either alone or if needed, with the help of the researcher to protect their privacy. Chi-square, fisher exact test and multiple logistic Regression model were used to assess the effective factors on the RACP. The data were analyzed by SPSS software version 26.

RESULTS: A total of 641 people with an average age of 36.85 ± 12.05 years participated in this study. Of those, 377 (58.8%) had high RACP. The logistics model showed an association between the chance of readiness for receiving ACP with participants' education level, such that the chance of readiness in those with Master's or Ph.D. degrees was three times higher than those with a diploma (p = 0.00, OR:3.178(1.672, 6.043)). However, the chances of readiness in those with bachelor's degrees was not significantly different from those with a diploma (p = 0.936, OR: 0.984 (0.654, 1.479)). Moreover, the chance of readiness was 1.5 higher in participants over 40 years of age compared with participants under the age of 40 (P = 0.01, OR: 1.571(1.10, 2.23)).

CONCLUSION: According to the findings of this study, it can be concluded that there is a relatively RACP among people in Iranian society. The readiness of individuals for ACP increases by their age and education level. Therefore, by holding appropriate training intervention, we can increase the readiness of the public for ACP to improve their end-of-life outcome.

PMID:38982407 | DOI:10.1186/s12904-024-01496-2

Categories: Literature Watch

Co-regulatory network analysis of the main secondary metabolite (SM) biosynthesis in Crocus sativus L

Tue, 2024-07-09 06:00

Sci Rep. 2024 Jul 9;14(1):15839. doi: 10.1038/s41598-024-65870-z.

ABSTRACT

Saffron (Crocus sativus L.) is being embraced as the most important medicinal plant and the commercial source of saffron spice. Despite the beneficial economic and medicinal properties of saffron, the regulatory mechanism of the correlation of TFs and genes related to the biosynthesis of the apocarotenoids pathway is less obvious. Realizing these regulatory hierarchies of gene expression networks related to secondary metabolites production events is the main challenge owing to the complex and extensive interactions between the genetic behaviors. Recently, high throughput expression data have been highly feasible for constructing co-regulation networks to reveal the regulated processes and identifying novel candidate hub genes in response to complex processes of the biosynthesis of secondary metabolites. Herein, we performed Weighted Gene Co-expression Network Analysis (WGCNA), a systems biology method, to identify 11 regulated modules and hub TFs related to secondary metabolites. Three specialized modules were found in the apocarotenoids pathway. Several hub TFs were identified in notable modules, including MADS, C2H2, ERF, bZIP, HD-ZIP, and zinc finger protein MYB and HB, which were potentially associated with apocarotenoid biosynthesis. Furthermore, the expression levels of six hub TFs and six co-regulated genes of apocarotenoids were validated with RT-qPCR. The results confirmed that hub TFs specially MADS, C2H2, and ERF had a high correlation (P < 0.05) and a positive effect on genes under their control in apocarotenoid biosynthesis (CCD2, GLT2, and ADH) among different C. sativus ecotypes in which the metabolite contents were assayed. Promoter analysis of the co-expressed genes of the modules involved in apocarotenoids biosynthesis pathway suggested that not only are the genes co-expressed, but also share common regulatory motifs specially related to hub TFs of each module and that they may describe their common regulation. The result can be used to engineer valuable secondary metabolites of C. sativus by manipulating the hub regulatory TFs.

PMID:38982154 | DOI:10.1038/s41598-024-65870-z

Categories: Literature Watch

PKM2 aggregation drives metabolism reprograming during aging process

Tue, 2024-07-09 06:00

Nat Commun. 2024 Jul 9;15(1):5761. doi: 10.1038/s41467-024-50242-y.

ABSTRACT

While protein aggregation's association with aging and age-related diseases is well-established, the specific proteins involved and whether dissolving them could alleviate aging remain unclear. Our research addresses this gap by uncovering the role of PKM2 aggregates in aging. We find that PKM2 forms aggregates in senescent cells and organs from aged mice, impairing its enzymatic activity and glycolytic flux, thereby driving cells into senescence. Through a rigorous two-step small molecule library screening, we identify two compounds, K35 and its analog K27, capable of dissolving PKM2 aggregates and alleviating senescence. Further experiments show that treatment with K35 and K27 not only alleviate aging-associated signatures but also extend the lifespan of naturally and prematurely aged mice. These findings provide compelling evidence for the involvement of PKM2 aggregates in inducing cellular senescence and aging phenotypes, and suggest that targeting these aggregates could be a promising strategy for anti-aging drug discovery.

PMID:38982055 | DOI:10.1038/s41467-024-50242-y

Categories: Literature Watch

Upconverting Nanoparticle-based Enhanced Luminescence Lateral-Flow Assay for Urinary Biomarker Monitoring

Tue, 2024-07-09 06:00

ACS Appl Mater Interfaces. 2024 Jul 9. doi: 10.1021/acsami.4c06117. Online ahead of print.

ABSTRACT

Development of efficient portable sensors for accurately detecting biomarkers is crucial for early disease diagnosis, yet remains a significant challenge. To address this need, we introduce the enhanced luminescence lateral-flow assay, which leverages highly luminescent upconverting nanoparticles (UCNPs) alongside a portable reader and a smartphone app. The sensor's efficiency and versatility were shown for kidney health monitoring as a proof of concept. We engineered Er3+- and Tm3+-doped UCNPs coated with multiple layers, including an undoped inert matrix shell, a mesoporous silica shell, and an outer layer of gold (UCNP@mSiO2@Au). These coatings synergistically enhance emission by over 40-fold and facilitate biomolecule conjugation, rendering UCNP@mSiO2@Au easy to use and suitable for a broad range of bioapplications. Employing these optimized nanoparticles in lateral-flow assays, we successfully detected two acute kidney injury-related biomarkers─kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL)─in urine samples. Using our sensor platform, KIM-1 and NGAL can be accurately detected and quantified within the range of 0.1 to 20 ng/mL, boasting impressively low limits of detection at 0.28 and 0.23 ng/mL, respectively. Validating our approach, we analyzed clinical urine samples, achieving biomarker concentrations that closely correlated with results obtained via ELISA. Importantly, our system enables biomarker quantification in less than 15 min, underscoring the performance of our novel UCNP-based approach and its potential as reliable, rapid, and user-friendly diagnostics.

PMID:38980927 | DOI:10.1021/acsami.4c06117

Categories: Literature Watch

Stem Cell-Derived Extracellular Vesicle-Bearing Injectable Hydrogel for Collagen Generation in Dermis

Tue, 2024-07-09 06:00

ACS Appl Mater Interfaces. 2024 Jul 9. doi: 10.1021/acsami.4c07434. Online ahead of print.

ABSTRACT

Despite the remarkable advances of dermal fillers that reduce wrinkles caused by dermis thickness reduction, they still lack effective hydrogel systems that stimulate collagen generation along with injection convenience. Here, we develop a stem cell-derived extracellular vesicle (EV)-bearing thermosensitive hydrogel (EVTS-Gel) for effective in vivo collagen generation. The TS-Gel undergoes sol-gel transition at 32.6 °C, as demonstrated by the storage and loss moduli crossover. Moreover, the TS-Gel and the EVTS-Gel have comparable rheological properties. Both hydrogels are injected in a sol state; hence, they require lower injection forces than conventional hydrogel-based dermal fillers. When locally administered to mouse skin, the TS-Gel extends the retention time of EVs by 2.23 times. Based on the nature of the controlled EV release, the EVTS-Gel significantly inhibits the dermis thickness reduction caused by aging compared to the bare EV treatment for 24 weeks. After a single treatment, the collagen layer thickness of the EVTS-Gel-treated dermis becomes 2.64-fold thicker than that of the bare EV-treated dermis. Notably, the collagen generation efficacy of the bare EV is poorer than that of the EVTS-Gel of a 10× lesser dose. Overall, the EVTS-Gel shows potential as an antiaging dermal filler for in vivo collagen generation.

PMID:38980897 | DOI:10.1021/acsami.4c07434

Categories: Literature Watch

The TSC22D, WNK, and NRBP gene families exhibit functional buffering and evolved with Metazoa for cell volume regulation

Tue, 2024-07-09 06:00

Cell Rep. 2024 Jul 8;43(7):114417. doi: 10.1016/j.celrep.2024.114417. Online ahead of print.

ABSTRACT

The ability to sense and respond to osmotic fluctuations is critical for the maintenance of cellular integrity. We used gene co-essentiality analysis to identify an unappreciated relationship between TSC22D2, WNK1, and NRBP1 in regulating cell volume homeostasis. All of these genes have paralogs and are functionally buffered for osmo-sensing and cell volume control. Within seconds of hyperosmotic stress, TSC22D, WNK, and NRBP family members physically associate into biomolecular condensates, a process that is dependent on intrinsically disordered regions (IDRs). A close examination of these protein families across metazoans revealed that TSC22D genes evolved alongside a domain in NRBPs that specifically binds to TSC22D proteins, which we have termed NbrT (NRBP binding region with TSC22D), and this co-evolution is accompanied by rapid IDR length expansion in WNK-family kinases. Our study reveals that TSC22D, WNK, and NRBP genes evolved in metazoans to co-regulate rapid cell volume changes in response to osmolarity.

PMID:38980795 | DOI:10.1016/j.celrep.2024.114417

Categories: Literature Watch

Nitric oxide releasing coatings for the prevention of viral and bacterial infections

Tue, 2024-07-09 06:00

Biomater Sci. 2024 Jul 9. doi: 10.1039/d4bm00172a. Online ahead of print.

ABSTRACT

Healthcare associated infections (HCAI) represent a significant burden worldwide contributing to morbidity and mortality and result in substantial economic consequences equating to billions annually. Although the impacts of HCAI have been felt for many years, the coronavirus pandemic has had a profound effect, escalating rates of HCAI, even with extensive preventative measures such as vaccination, personal protective equipment, and deep cleaning regimes. Therefore, there is an urgent need for new solutions to mitigate this serious health emergency. In this paper, the fabrication of nitric oxide (NO) releasing dual action polymer coatings for use in healthcare applications is described. The coatings are doped with the NO donor S-nitroso-N-acetylpenicillamine (SNAP) and release high payloads of NO in a sustained manner for in excess of 50 hours. These coatings are extensively characterized in multiple biologically relevant solutions and the antibacterial/antiviral efficacy is studied. For the first time, we assess antibacterial activity in a time course study (1, 2, 4 and 24 h) in both nutrient rich and nutrient poor conditions. Coatings exhibit excellent activity against Pseudomonas aeruginosa and methicillin resistant Staphylococcus aureus (MRSA), with up to complete reduction observed over 24 hours. Additionally, when tested against SARS-CoV-2, the coatings significantly reduced active virus in as little as 10 minutes. These promising results suggest that these coatings could be a valuable addition to existing preventative measures in the fight against HCAIs.

PMID:38980705 | DOI:10.1039/d4bm00172a

Categories: Literature Watch

By suppressing its MD-PhD fellowship programme, the Swiss National Science Foundation reduces the attractiveness of the physician-scientist career path

Tue, 2024-07-09 06:00

Swiss Med Wkly. 2024 Jul 4;154:3605. doi: 10.57187/s.3605.

ABSTRACT

No abstract available.

PMID:38980663 | DOI:10.57187/s.3605

Categories: Literature Watch

Metabolomics 2023 workshop report: moving toward consensus on best QA/QC practices in LC-MS-based untargeted metabolomics

Tue, 2024-07-09 06:00

Metabolomics. 2024 Jul 9;20(4):73. doi: 10.1007/s11306-024-02135-w.

ABSTRACT

INTRODUCTION: During the Metabolomics 2023 conference, the Metabolomics Quality Assurance and Quality Control Consortium (mQACC) presented a QA/QC workshop for LC-MS-based untargeted metabolomics.

OBJECTIVES: The Best Practices Working Group disseminated recent findings from community forums and discussed aspects to include in a living guidance document.

METHODS: Presentations focused on reference materials, data quality review, metabolite identification/annotation and quality assurance.

RESULTS: Live polling results and follow-up discussions offered a broad international perspective on QA/QC practices.

CONCLUSIONS: Community input gathered from this workshop series is being used to shape the living guidance document, a continually evolving QA/QC best practices resource for metabolomics researchers.

PMID:38980450 | DOI:10.1007/s11306-024-02135-w

Categories: Literature Watch

Seasonal metabolic dynamics of microeukaryotic plankton: a year-long metatranscriptomic study in a temperate sea

Tue, 2024-07-09 06:00

mBio. 2024 Jul 9:e0038324. doi: 10.1128/mbio.00383-24. Online ahead of print.

ABSTRACT

Seasonal fluctuations profoundly affect marine microeukaryotic plankton composition and metabolism, but accurately tracking these changes has been a long-standing challenge. In this study, we present a year-long metatranscriptomic data set from the Southern Bight of the North Sea, shedding light on the seasonal dynamics in temperate plankton ecosystems. We observe distinct shifts in active plankton species and their metabolic processes in response to seasonal changes. We characterized the metabolic signatures of different seasonal phases in detail, thereby revealing the metabolic versatility of dinoflagellates, the heterotrophic dietary strategy of Phaeocystis during its late-stage blooms, and stark variations in summer and fall diatom abundance and metabolic activity across nearby sampling stations. Our data illuminate the varied contributions of microeukaryotic taxa to biomass production and nutrient cycling at different times of the year and allow delineation of their ecological niches.

IMPORTANCE: Ecosystem composition and metabolic functions of temperate marine microeukaryote plankton are strongly influenced by seasonal dynamics. Although monitoring of species composition of microeukaryotes has expanded recently, few methods also contain seasonally resolved information on ecosystem functioning. We generated a year-long spatially resolved metatranscriptomic data set to assess seasonal dynamics of microeukaryote species and their associated metabolic functions in the Southern Bight of the North Sea. Our study underscores the potential of metatranscriptomics as a powerful tool for advancing our understanding of marine ecosystem functionality and resilience in response to environmental changes, emphasizing its potential in continuous marine ecosystem monitoring to enhance our ecological understanding of the ocean's eukaryotic microbiome.

PMID:38980008 | DOI:10.1128/mbio.00383-24

Categories: Literature Watch

Body Mass Index and Hypertension as Mediators of the Association Between Age at Menarche and Subclinical Atherosclerosis: A Sex-Specific Mendelian Randomization Analysis

Tue, 2024-07-09 06:00

J Am Heart Assoc. 2024 Jul 9:e032192. doi: 10.1161/JAHA.123.032192. Online ahead of print.

ABSTRACT

BACKGROUND: Early age at menarche (AAM) has been associated with a higher risk of carotid artery intima-media thickness (cIMT), an indicator of subclinical vascular disease, albeit the mechanisms underlying this association remain elusive. A better understanding of the relationship between AAM, modifiable cardiometabolic risk factors, and subclinical atherosclerosis may contribute to improved primary prevention and cardiovascular disease treatment. We aimed to investigate the putative causal role of AAM on cIMT, and to identify and quantify the potentially mediatory effects of cardiometabolic risk factors underlying this relationship.

METHODS AND RESULTS: We conducted linkage disequilibrium score regression analyses between our exposure of interest, AAM, our outcome of interest, cIMT and potential mediators of the AAM-cIMT association to gauge cross-trait genetic overlap. We considered as mediators the modifiable anthropometric risk factors body mass index (BMI), systolic blood pressure (SBP), lipid traits (total cholesterol, triglycerides, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol), and glycemic traits (fasting glucose). We then leveraged the paradigm of Mendelian randomization to infer causality between AAM and cIMT, and to identify whether cardiometabolic risk factors served as potential mediators of this effect. Our analyses showed that genetically predicted AAM was inversely associated with cIMT, BMI, SBP, and triglycerides, and positively associated with high-density lipoprotein, low-density lipoprotein, and total cholesterol. We showed that the effect of genetically predicted AAM on cIMT may be partially mediated through BMI (20.1% [95% CI, 1.4% to 38.9%]) and SBP (13.5% [95% CI, 0.5%-26.6%]). Our cluster-specific Mendelian randomization revealed heterogeneous causal effect estimates of age at menarche on BMI and SBP.

CONCLUSIONS: We highlight supporting evidence for a potential causal association between earlier AAM and cIMT, and almost one third of the effect of AAM on cIMT may be mediated by BMI and SBP. Early intervention aimed at lowering BMI and hypertension may be beneficial in reducing the risk of developing subclinical atherosclerosis due to earlier age at menarche.

PMID:38979809 | DOI:10.1161/JAHA.123.032192

Categories: Literature Watch

Strategic design and development of a siderophore mimic: pioneering anticancer therapy <em>via</em> ROS generation and ferroptosis

Tue, 2024-07-09 06:00

Dalton Trans. 2024 Jul 9. doi: 10.1039/d4dt01461h. Online ahead of print.

ABSTRACT

We designed a tris-catecholate-based siderophore mimic, H6-T-CATL, to selectively chelate iron(III) from mitochondrial cytochromes and other iron-containing proteins within cellular matrices. This strategic sequestration aims to trigger apoptosis or ferroptosis in cancer cells through the glutathione (GSH)-dependent release of reduced iron and subsequent ROS-mediated cytotoxicity. Synthesis of H6-T-CATL involved precise peptide coupling reactions. Using the Fe(III)-porphyrin model (Fe-TPP-Cl), akin to cytochrome c, we studied H6-T-CATL's ability to extract iron(III), yielding a binding constant (Krel) of 1014 for the resulting iron(III) complex (FeIII-T-CATL)3-. This complex readily underwent GSH-mediated reduction to release bioavailable iron(II), which catalyzed Fenton-like reactions generating hydroxyl radicals (˙OH), confirmed by spectroscopic analyses. Our research underscores the potential of H6-T-CATL to induce cancer cell death by depleting iron(III) from cellular metalloproteins, releasing pro-apoptotic iron(II). Evaluation across various cancer types, including normal cells, demonstrated H6-T-CATL's cytotoxicity through ROS production, mitochondrial dysfunction, and activation of ferroptosis and DNA damage pathways. These findings propose a novel mechanism for cancer therapy, leveraging endogenous iron stores within cells. H6-T-CATL emerges as a promising next-generation anticancer agent, exploiting iron metabolism vulnerabilities to induce selective cancer cell death through ferroptosis induction.

PMID:38979715 | DOI:10.1039/d4dt01461h

Categories: Literature Watch

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