PubMed
The Methylome of Motile Cilia
Mol Biol Cell. 2024 May 2:mbcE24030130. doi: 10.1091/mbc.E24-03-0130. Online ahead of print.ABSTRACTCilia are highly complex motile, sensory, and secretory organelles that contain perhaps 1,000 or more distinct protein components, many of which are subject to various post-translational modifications such as phosphorylation, N-terminal acetylation, and proteolytic processing. Another common modification is the addition of one or more methyl groups to the side chains of arginine and lysine residues. These tunable additions delocalize the side-chain charge, decrease hydrogen bond capacity, and increase both bulk and hydrophobicity. Methylation is usually mediated by S-adenosylmethionine (SAM)-dependent methyltransferases and reversed by demethylases. Previous studies have identified several ciliary proteins that are subject to methylation including axonemal dynein heavy chains that are modified by a cytosolic methyltransferase. Here we have performed an extensive proteomic analysis of multiple independently derived cilia samples to assess the potential for SAM metabolism and the extent of methylation in these organelles. We find that cilia contain all the enzymes needed for generation of the SAM methyl donor and recycling of the S-adenosylhomocysteine and tetrahydrofolate byproducts. In addition, we find that at least one hundred and fifty-five distinct ciliary proteins are methylated, in some cases at multiple sites. These data provide a comprehensive resource for studying the consequences of methyl marks on ciliary biology.PMID:38696262 | DOI:10.1091/mbc.E24-03-0130
Multicenter PET image harmonization using generative adversarial networks
Eur J Nucl Med Mol Imaging. 2024 May 2. doi: 10.1007/s00259-024-06708-8. Online ahead of print.ABSTRACTPURPOSE: To improve reproducibility and predictive performance of PET radiomic features in multicentric studies by cycle-consistent generative adversarial network (GAN) harmonization approaches.METHODS: GAN-harmonization was developed to harmonize whole-body PET scans to perform image style and texture translation between different centers and scanners. GAN-harmonization was evaluated by application to two retrospectively collected open datasets and different tasks. First, GAN-harmonization was performed on a dual-center lung cancer cohort (127 female, 138 male) where the reproducibility of radiomic features in healthy liver tissue was evaluated. Second, GAN-harmonization was applied to a head and neck cancer cohort (43 female, 154 male) acquired from three centers. Here, the clinical impact of GAN-harmonization was analyzed by predicting the development of distant metastases using a logistic regression model incorporating first-order statistics and texture features from baseline 18F-FDG PET before and after harmonization.RESULTS: Image quality remained high (structural similarity: left kidney ≥ 0.800, right kidney ≥ 0.806, liver ≥ 0.780, lung ≥ 0.838, spleen ≥ 0.793, whole-body ≥ 0.832) after image harmonization across all utilized datasets. Using GAN-harmonization, inter-site reproducibility of radiomic features in healthy liver tissue increased at least by ≥ 5 ± 14% (first-order), ≥ 16 ± 7% (GLCM), ≥ 19 ± 5% (GLRLM), ≥ 16 ± 8% (GLSZM), ≥ 17 ± 6% (GLDM), and ≥ 23 ± 14% (NGTDM). In the head and neck cancer cohort, the outcome prediction improved from AUC 0.68 (95% CI 0.66-0.71) to AUC 0.73 (0.71-0.75) by application of GAN-harmonization.CONCLUSIONS: GANs are capable of performing image harmonization and increase reproducibility and predictive performance of radiomic features derived from different centers and scanners.PMID:38696130 | DOI:10.1007/s00259-024-06708-8
Multiple mycotoxins associated with maize (Zea mays L.) grains harvested from subsistence farmers' fields in southwestern Ethiopia
Mycotoxin Res. 2024 May 2. doi: 10.1007/s12550-024-00536-3. Online ahead of print.ABSTRACTFifty-four maize grain samples freshly harvested from subsistence farmers' fields in southwestern Ethiopia were analyzed for multiple mycotoxins using liquid chromatography-tandem mass spectrometric (LC-MS/MS) method following extraction by acetonitrile/water/acetic acid on a rotary shaker. The grain samples were contaminated with a total of 164 metabolites, of which Fusarium and Penicillium metabolites were the most prevalent accounting for 27 and 30%, respectively. All the major mycotoxins and derivatives except one (citrinin) were of Fusarium origin. Zearalenone was the most frequent major mycotoxin occurring in 74% of the samples at concentrations of 0.32-1310 µg/kg. It was followed by nivalenol (63%), zearalenone-sulfate (44%), and fumonisin B1 (41%). Nivalenol, nivalenol glucoside, and fusarenon-X were detected at unusually high levels of 8-1700 µg/kg, 21-184 µg/kg, and 33-149 µg/kg, respectively. Deoxynivalenol and DON-3 glucoside contaminated 32% of the samples, each at levels of 15.9-5140 µg/kg and 10-583 µg/kg, respectively. Moniliformin and W493B occurred in 96 and 22% samples at levels of 3.27-4410 µg/kg and 3-652 µg/kg, respectively. Fumonisins were also detected in the samples at levels of 9-6770 µg/kg (B1), 16-1830 µg/kg (B2), 9.5-808 µg/kg (B3), and 1.3-128 µg/kg (A1). This study confirmed the presence of an array of mycotoxins contaminating maize grains right from the field. The effect of the co-occurring mycotoxins on consumers' health should be investigated along with that of the newly emerging ones. Results of the current study call for application of pre-harvest mycotoxin mitigation strategies to safeguard maize-based food and feed.PMID:38696043 | DOI:10.1007/s12550-024-00536-3
Multi-omics bioactivity profile-based chemical grouping and read-across: a case study with Daphnia magna and azo dyes
Arch Toxicol. 2024 May 2. doi: 10.1007/s00204-024-03759-6. Online ahead of print.ABSTRACTGrouping/read-across is widely used for predicting the toxicity of data-poor target substance(s) using data-rich source substance(s). While the chemical industry and the regulators recognise its benefits, registration dossiers are often rejected due to weak analogue/category justifications based largely on the structural similarity of source and target substances. Here we demonstrate how multi-omics measurements can improve confidence in grouping via a statistical assessment of the similarity of molecular effects. Six azo dyes provided a pool of potential source substances to predict long-term toxicity to aquatic invertebrates (Daphnia magna) for the dye Disperse Yellow 3 (DY3) as the target substance. First, we assessed the structural similarities of the dyes, generating a grouping hypothesis with DY3 and two Sudan dyes within one group. Daphnia magna were exposed acutely to equi-effective doses of all seven dyes (each at 3 doses and 3 time points), transcriptomics and metabolomics data were generated from 760 samples. Multi-omics bioactivity profile-based grouping uniquely revealed that Sudan 1 (S1) is the most suitable analogue for read-across to DY3. Mapping ToxPrint structural fingerprints of the dyes onto the bioactivity profile-based grouping indicated an aromatic alcohol moiety could be responsible for this bioactivity similarity. The long-term reproductive toxicity to aquatic invertebrates of DY3 was predicted from S1 (21-day NOEC, 40 µg/L). This prediction was confirmed experimentally by measuring the toxicity of DY3 in D. magna. While limitations of this 'omics approach are identified, the study illustrates an effective statistical approach for building chemical groups.PMID:38695895 | DOI:10.1007/s00204-024-03759-6
Septin 7 interacts with Numb to preserve sarcomere structural organization and muscle contractile function
Elife. 2024 May 2;12:RP89424. doi: 10.7554/eLife.89424.ABSTRACTHere, we investigated the mechanisms by which aging-related reductions of the levels of Numb in skeletal muscle fibers contribute to loss of muscle strength and power, two critical features of sarcopenia. Numb is an adaptor protein best known for its critical roles in development, including asymmetric cell division, cell-type specification, and termination of intracellular signaling. Numb expression is reduced in old humans and mice. We previously showed that, in mouse skeletal muscle fibers, Numb is localized to sarcomeres where it is concentrated near triads; conditional inactivation of Numb and a closely related protein Numb-like (Numbl) in mouse myofibers caused weakness, disorganization of sarcomeres, and smaller mitochondria with impaired function. Here, we found that a single knockout of Numb in myofibers causes reduction in tetanic force comparable to a double Numb, Numbl knockout. We found by proteomics analysis of protein complexes isolated from C2C12 myotubes by immunoprecipitation using antibodies against Numb that Septin 7 is a potential Numb-binding partner. Septin 7 is a member of the family of GTP-binding proteins that organize into filaments, sheets, and rings, and is considered part of the cytoskeleton. Immunofluorescence evaluation revealed a partial overlap of staining for Numb and Septin 7 in myofibers. Conditional, inducible knockouts of Numb led to disorganization of Septin 7 staining in myofibers. These findings indicate that Septin 7 is a Numb-binding partner and suggest that interactions between Numb and Septin 7 are critical for structural organization of the sarcomere and muscle contractile function.PMID:38695862 | DOI:10.7554/eLife.89424
The fungus Acremonium alternatum enhances salt stress tolerance by regulating host redox homeostasis and phytohormone signaling
Physiol Plant. 2024 May-Jun;176(3):e14328. doi: 10.1111/ppl.14328.ABSTRACTWhile endophytic fungi offer promising avenues for bolstering plant resilience against abiotic stressors, the molecular mechanisms behind this biofortification remain largely unknown. This study employed a multifaceted approach, combining plant physiology, proteomic, metabolomic, and targeted hormonal analyses to illuminate the early response of Brassica napus to Acremonium alternatum during the nascent stages of their interaction. Notably, under optimal growth conditions, the initial reaction to fungus was relatively subtle, with no visible alterations in plant phenotype and only minor impacts on the proteome and metabolome. Interestingly, the identified proteins associated with the Acremonium response included TUDOR 1, Annexin D4, and a plastidic K+ efflux antiporter, hinting at potential processes that could counter abiotic stressors, particularly salt stress. Subsequent experiments validated this hypothesis, showcasing significantly enhanced growth in Acremonium-inoculated plants under salt stress. Molecular analyses revealed a profound impact on the plant's proteome, with over 50% of salt stress response proteins remaining unaffected in inoculated plants. Acremonium modulated ribosomal proteins, increased abundance of photosynthetic proteins, enhanced ROS metabolism, accumulation of V-ATPase, altered abundances of various metabolic enzymes, and possibly promoted abscisic acid signaling. Subsequent analyses validated the accumulation of this hormone and its enhanced signaling. Collectively, these findings indicate that Acremonium promotes salt tolerance by orchestrating abscisic acid signaling, priming the plant's antioxidant system, as evidenced by the accumulation of ROS-scavenging metabolites and alterations in ROS metabolism, leading to lowered ROS levels and enhanced photosynthesis. Additionally, it modulates ion sequestration through V-ATPase accumulation, potentially contributing to the observed decrease in chloride content.PMID:38695265 | DOI:10.1111/ppl.14328
Neuroinflammation Plays a Potential Role in the Medulla Oblongata after Moderate Traumatic Brain Injury in Mice as Revealed by Nontargeted Metabonomics Analysis
J Neurotrauma. 2024 May 2. doi: 10.1089/neu.2023.0536. Online ahead of print.ABSTRACTModerate traumatic brain injury (mTBI) involves a series of complex pathophysiological processes in not only the area in direct contact with mechanical violence but also other brain regions far from the injury site, which may be important factors influencing subsequent neurological dysfunction or death. The medulla oblongata (MO) is a key area for the maintenance of basic respiratory and circulatory functions, whereas the pathophysiological processes after mTBI have rarely drawn the attention of researchers. In this study, we established a closed-head cortical contusion injury model, identified 6 different time points that covered the acute, subacute and chronic phases, and then used nontargeted metabolomics to identify and analyse the changes in differential metabolites (DMs) and metabolic pathways in the MO region. Our results showed that the metabolic profile of the MO region underwent specific changes over time: harmaline, riboflavin and dephospho-coenzyme A were identified as the key DMs and play important roles in reducing inflammation, enhancing antioxidation and maintaining homeostasis. Choline and glycerophospholipid metabolism were identified as the key pathways related to the changes in MO metabolism at different phases. In addition, we confirmed increases in the levels of inflammatory factors and the activation of astrocytes and microglia by Western blot and immunofluorescence staining, and these findings were consistent with the nontargeted metabolomics results. These findings suggest that neuroinflammation plays a central role in MO neuropathology after mTBI and provide new insights into the complex pathophysiologic mechanisms involved after mTBI.PMID:38695184 | DOI:10.1089/neu.2023.0536
Research on the metabolic regulation mechanism of Yangyin Qingfei decoction plus in severe pneumonia caused by <em>Mycoplasma pneumoniae</em> in mice
Front Pharmacol. 2024 Apr 17;15:1376812. doi: 10.3389/fphar.2024.1376812. eCollection 2024.ABSTRACTIntroduction: With amazing clinical efficacy, Yangyin Qingfei Decoction Plus (YQDP), a well-known and age-old Chinese compound made of ten Chinese botanical drugs, is utilized in clinical settings to treat a range of respiratory conditions. This study examines the impact of Yangyin Qingfei Decoction (YQDP) on lung tissue metabolic products in severe Mycoplasma pneumoniae pneumonia (SMPP) model mice and examines the mechanism of YQDP in treating MP infection using UPLC-MS/MS technology. Methods: YQDP's chemical composition was ascertained by the use of Agilent 1260 Ⅱ high-performance liquid chromatography. By using a nasal drip of 1010 CCU/mL MP bacterial solution, an SMPP mouse model was created. The lung index, pathology and ultrastructural observation of lung tissue were utilized to assess the therapeutic effect of YQDP in SMPP mice. Lung tissue metabolites were found in the normal group, model group, and YQDP group using UPLC-MS/MS technology. Using an enzyme-linked immunosorbent test (ELISA), the amount of serum inflammatory factors, such as interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α), was found. Additionally, the protein expression of PI3K, P-PI3K, AKT, P-AKT, NF-κB, and P-NF-κB was found using Western blot. Results: The contents of chlorogenic acid, paeoniflorin, forsythrin A, forsythrin, and paeonol in YQDP were 3.480 ± 0.051, 3.255 ± 0.040, 3.612 ± 0.017, 1.757 ± 0.031, and 1.080 ± 0.007 mg/g respectively. YQDP can considerably lower the SMPP mice's lung index (p < 0.05). In the lung tissue of YQDP groups, there has been a decrease (p < 0.05) in the infiltration of inflammatory cells at varying concentrations in the alveoli compared with the model group. A total of 47 distinct metabolites, including choline phosphate, glutamyl lysine, L-tyrosine, 6-thioinosine, Glu Trp, 5-hydroxydecanoate, etc., were linked to the regulation of YQDP, according to metabolomics study. By controlling the metabolism of porphyrins, pyrimidines, cholines, fatty acids, sphingolipids, glycerophospholipids, ferroptosis, steroid hormone biosynthesis, and unsaturated fatty acid biosynthesis, enrichment analysis suggested that YQDP may be used to treat SMPP. YQDP can lower the amount of TNF-α and IL-6 in model group mice as well as downregulate P-PI3K, P-AKT, and P-NF-κB expression (p < 0.05). Conclusion: A specific intervention effect of YQDP is observed in SMPP model mice. Through the PI3K/Akt/NF-κB signaling pathways, YQDP may have therapeutic benefits by regulating the body's metabolism of α-Linoleic acid, sphingolipids, glycerophospholipids, arachidonic acid, and the production of unsaturated fatty acids.PMID:38694915 | PMC:PMC11061391 | DOI:10.3389/fphar.2024.1376812
Fecal microbiota composition, serum metabolomics, and markers of inflammation in dogs fed a raw meat-based diet compared to those on a kibble diet
Front Vet Sci. 2024 Apr 17;11:1328513. doi: 10.3389/fvets.2024.1328513. eCollection 2024.ABSTRACTINTRODUCTION: Despite the potential health risks associated with feeding raw and non-traditional diets, the use of these diets in dogs is increasing, yet the health outcomes associated with these diets is not well understood. This study investigates the effect of feeding dogs a kibble or raw meat-based diets on fecal microbiota composition, serum metabolomics and inflammatory markers.METHODS: Clinically healthy dogs with a history of consuming either kibble (KD, n = 27) or raw meat-based diets (RMBD, n = 28) for more than 1 year were enrolled. Dogs were fed a standardized diet of either a single brand of KD or RMBD for 28 days. Serum and fecal samples were collected for analysis of microbiota, metabolomics, and inflammatory markers. Multiple regression analysis was performed for each of the metabolites and inflammatory markers, with feed group, age and BCS included as independent variables.RESULTS: The fecal microbiota composition differed between the KD and RMBD groups. Beta-diversity and some indices of alpha-diversity (i.e., Shannon and Simpson) were different between the two diet groups. Sixty- three serum metabolites differed between KD and RMBD-fed dogs with the majority reflecting the differences in macronutrient composition of the two diets.Fecal IAP, IgG and IgA were significantly higher in RMBD dogs compared to KD dogs, while systemic markers of inflammation, including serum c-reactive protein (CRP), galectin, secretory receptor of advanced glycation end-products (sRAGE), haptoglobin, and serum IgG were similar in dogs fed either diet.DISCUSSION: Diet composition significantly affected fecal microbiota composition and metabolome. Although it had a potentially beneficial effect on local inflammatory markers, feeding RMBD had no impact on systemic inflammation. The influence of these changes on long term health outcomes provides an area for future study.PMID:38694479 | PMC:PMC11061498 | DOI:10.3389/fvets.2024.1328513
The nonvesicular sterol transporter Aster-C plays a minor role in whole body cholesterol balance
Front Physiol. 2024 Apr 17;15:1371096. doi: 10.3389/fphys.2024.1371096. eCollection 2024.ABSTRACTINTRODUCTION: The Aster-C protein (encoded by the Gramd1c gene) is an endoplasmic reticulum (ER) resident protein that has been reported to transport cholesterol from the plasma membrane to the ER. Although there is a clear role for the closely-related Aster-B protein in cholesterol transport and downstream esterification in the adrenal gland, the specific role for Aster-C in cholesterol homeostasis is not well understood. Here, we have examined whole body cholesterol balance in mice globally lacking Aster-C under low or high dietary cholesterol conditions.METHOD: Age-matched Gramd1c +/+ and Gramd1c -/- mice were fed either low (0.02%, wt/wt) or high (0.2%, wt/wt) dietarycholesterol and levels of sterol-derived metabolites were assessed in the feces, liver, and plasma.RESULTS: Compared to wild type controls (Gramd1c +/+) mice, mice lackingGramd1c (Gramd1c -/-) have no significant alterations in fecal, liver, or plasma cholesterol. Given the potential role for Aster C in modulating cholesterol metabolism in diverse tissues, we quantified levels of cholesterol metabolites such as bile acids, oxysterols, and steroid hormones. Compared to Gramd1c +/+ controls, Gramd1c -/- mice had modestly reduced levels of select bile acid species and elevated cortisol levels, only under low dietary cholesterol conditions. However, the vast majority of bile acids, oxysterols, and steroid hormones were unaltered in Gramd1c -/- mice. Bulk RNA sequencing in the liver showed that Gramd1c -/- mice did not exhibit alterations in sterol-sensitive genes, but instead showed altered expression of genes in major urinary protein and cytochrome P450 (CYP) families only under low dietary cholesterol conditions.DISCUSSION: Collectively, these data indicate nominal effects of Aster-C on whole body cholesterol transport and metabolism under divergent dietary cholesterol conditions. These results strongly suggest that Aster-C alone is not sufficient to control whole body cholesterol balance, but can modestly impact circulating cortisol and bile acid levels when dietary cholesterol is limited.PMID:38694206 | PMC:PMC11061533 | DOI:10.3389/fphys.2024.1371096
Remodeling Intestinal Microbiota Alleviates Severe Combined Hyperlipidemia-Induced Nonalcoholic Steatohepatitis and Atherosclerosis in LDLR<sup>-/-</sup> Hamsters
Research (Wash D C). 2024 Apr 29;7:0363. doi: 10.34133/research.0363. eCollection 2024.ABSTRACTCombined hyperlipidemia (CHL) manifests as elevated cholesterol and triglycerides, associated with fatty liver and cardiovascular diseases. Emerging evidence underscores the crucial role of the intestinal microbiota in metabolic disorders. However, the potential therapeutic viability of remodeling the intestinal microbiota in CHL remains uncertain. In this study, CHL was induced in low-density lipoprotein receptor-deficient (LDLR-/-) hamsters through an 8-week high-fat and high-cholesterol (HFHC) diet or a 4-month high-cholesterol (HC) diet. Placebo or antibiotics were administered through separate or cohousing approaches. Analysis through 16S rDNA sequencing revealed that intermittent antibiotic treatment and the cohousing approach effectively modulated the gut microbiota community without impacting its overall abundance in LDLR-/- hamsters exhibiting severe CHL. Antibiotic treatment mitigated HFHC diet-induced obesity, hyperglycemia, and hyperlipidemia, enhancing thermogenesis and alleviating nonalcoholic steatohepatitis (NASH), concurrently reducing atherosclerotic lesions in LDLR-/- hamsters. Metabolomic analysis revealed a favorable liver lipid metabolism profile. Increased levels of microbiota-derived metabolites, notably butyrate and glycylglycine, also ameliorated NASH and atherosclerosis in HFHC diet-fed LDLR-/- hamsters. Notably, antibiotics, butyrate, and glycylglycine treatment exhibited protective effects in LDLR-/- hamsters on an HC diet, aligning with outcomes observed in the HFHC diet scenario. Our findings highlight the efficacy of remodeling gut microbiota through antibiotic treatment and cohousing in improving obesity, NASH, and atherosclerosis associated with refractory CHL. Increased levels of beneficial microbiota-derived metabolites suggest a potential avenue for microbiome-mediated therapies in addressing CHL-associated diseases.PMID:38694198 | PMC:PMC11062505 | DOI:10.34133/research.0363
Seeing beyond words: Visualizing autism spectrum disorder biomarker insights
Heliyon. 2024 Apr 26;10(9):e30420. doi: 10.1016/j.heliyon.2024.e30420. eCollection 2024 May 15.ABSTRACTOBJECTIVE: This study employs bibliometric and visual analysis to elucidate global research trends in Autism Spectrum Disorder (ASD) biomarkers, identify critical research focal points, and discuss the potential integration of diverse biomarker modalities for precise ASD assessment.METHODS: A comprehensive bibliometric analysis was conducted using data from the Web of Science Core Collection database until December 31, 2022. Visualization tools, including R, VOSviewer, CiteSpace, and gCLUTO, were utilized to examine collaborative networks, co-citation patterns, and keyword associations among countries, institutions, authors, journals, documents, and keywords.RESULTS: ASD biomarker research emerged in 2004, accumulating a corpus of 4348 documents by December 31, 2022. The United States, with 1574 publications and an H-index of 213, emerged as the most prolific and influential country. The University of California, Davis, contributed significantly with 346 publications and an H-index of 69, making it the leading institution. Concerning journals, the Journal of Autism and Developmental Disorders, Autism Research, and PLOS ONE were the top three publishers of ASD biomarker-related articles among a total of 1140 academic journals. Co-citation and keyword analyses revealed research hotspots in genetics, imaging, oxidative stress, neuroinflammation, gut microbiota, and eye tracking. Emerging topics included "DNA methylation," "eye tracking," "metabolomics," and "resting-state fMRI."CONCLUSION: The field of ASD biomarker research is dynamically evolving. Future endeavors should prioritize individual stratification, methodological standardization, the harmonious integration of biomarker modalities, and longitudinal studies to advance the precision of ASD diagnosis and treatment.PMID:38694128 | PMC:PMC11061761 | DOI:10.1016/j.heliyon.2024.e30420
Disorders of fatty acid homeostasis
J Inherit Metab Dis. 2024 May 1. doi: 10.1002/jimd.12734. Online ahead of print.ABSTRACTHumans derive fatty acids (FA) from exogenous dietary sources and/or endogenous synthesis from acetyl-CoA, although some FA are solely derived from exogenous sources ("essential FA"). Once inside cells, FA may undergo a wide variety of different modifications, which include their activation to their corresponding CoA ester, the introduction of double bonds, the 2- and ω-hydroxylation and chain elongation, thereby generating a cellular FA pool which can be used for the synthesis of more complex lipids. The biological properties of complex lipids are very much determined by their molecular composition in terms of the FA incorporated into these lipid species. This immediately explains the existence of a range of genetic diseases in man, often with severe clinical consequences caused by variants in one of the many genes coding for enzymes responsible for these FA modifications. It is the purpose of this review to describe the current state of knowledge about FA homeostasis and the genetic diseases involved. This includes the disorders of FA activation, desaturation, 2- and ω-hydroxylation, and chain elongation, but also the disorders of FA breakdown, including disorders of peroxisomal and mitochondrial α- and β-oxidation.PMID:38693715 | DOI:10.1002/jimd.12734
Affinity-Driven Aryl Diazonium Labeling of Peptide Receptors on Living Cells
J Am Chem Soc. 2024 May 1. doi: 10.1021/jacs.4c04672. Online ahead of print.ABSTRACTPeptide-receptor interactions play critical roles in a wide variety of physiological processes. Methods to link bioactive peptides covalently to unmodified receptors on the surfaces of living cells are valuable for studying receptor signaling, dynamics, and trafficking and for identifying novel peptide-receptor interactions. Here, we utilize peptide analogues bearing deactivated aryl diazonium groups for the affinity-driven labeling of unmodified receptors. We demonstrate that aryl diazonium-bearing peptide analogues can covalently label receptors on the surface of living cells using both the neurotensin and the glucagon-like peptide 1 receptor systems. Receptor labeling occurs in the complex environment of the cell surface in a sequence-specific manner. We further demonstrate the utility of this covalent labeling approach for the visualization of peptide receptors by confocal fluorescence microscopy and for the enrichment and identification of labeled receptors by mass spectrometry-based proteomics. Aryl diazonium-based affinity-driven receptor labeling is attractive due to the high abundance of tyrosine and histidine residues susceptible to azo coupling in the peptide binding sites of receptors, the ease of incorporation of aryl diazonium groups into peptides, and the relatively small size of the aryl diazonium group. This approach should prove to be a powerful and relatively general method to study peptide-receptor interactions in cellular contexts.PMID:38693710 | DOI:10.1021/jacs.4c04672
MobiLipid: A Tool for Enhancing CCS Quality Control of Ion Mobility-Mass Spectrometry Lipidomics by Internal Standardization
Anal Chem. 2024 May 1. doi: 10.1021/acs.analchem.4c01253. Online ahead of print.ABSTRACTIon mobility-mass spectrometry (IM-MS) offers benefits for lipidomics by obtaining IM-derived collision cross sections (CCS), a conditional property of an ion that can enhance lipid identification. While drift tube (DT) IM-MS retains a direct link to the primary experimental method to derive CCS values, other IM technologies rely solely on external CCS calibration, posing challenges due to dissimilar chemical properties between lipids and calibrants. To address this, we introduce MobiLipid, a novel tool facilitating the CCS quality control of IM-MS lipidomics workflows by internal standardization. MobiLipid utilizes a newly established DTCCSN2 library for uniformly (U)13C-labeled lipids, derived from a U13C-labeled yeast extract, containing 377 DTCCSN2 values. This automated open-source R Markdown tool enables internal monitoring and straightforward compensation for CCSN2 biases. It supports lipid class- and adduct-specific CCS corrections, requiring only three U13C-labeled lipids per lipid class-adduct combination across 10 lipid classes without requiring additional external measurements. The applicability of MobiLipid is demonstrated for trapped IM (TIM)-MS measurements of an unlabeled yeast extract spiked with U13C-labeled lipids. Monitoring the CCSN2 biases of TIMCCSN2 values compared to DTCCSN2 library entries utilizing MobiLipid resulted in mean absolute biases of 0.78% and 0.33% in positive and negative ionization mode, respectively. By applying the CCS correction integrated into the tool for the exemplary data set, the mean absolute CCSN2 biases of 10 lipid classes could be reduced to approximately 0%.PMID:38693701 | DOI:10.1021/acs.analchem.4c01253
Comparison of discovery rates and prognostic utility of [<sup>68</sup>Ga]Ga-PSMA-11 PET/CT and circulating tumor DNA in prostate cancer-a cross-sectional study
Eur J Nucl Med Mol Imaging. 2024 May 2. doi: 10.1007/s00259-024-06698-7. Online ahead of print.ABSTRACTBACKGROUND: Circulating-tumor DNA (ctDNA) and prostate-specific membrane antigen (PSMA) ligand positron-emission tomography (PET) enable minimal-invasive prostate cancer (PCa) detection and survival prognostication. The present study aims to compare their tumor discovery abilities and prognostic values.METHODS: One hundred thirty men with confirmed PCa (70.5 ± 8.0 years) who underwent [68Ga]Ga-PSMA-11 PET/CT (184.8 ± 19.7 MBq) imaging and plasma sample collection (March 2019-August 2021) were included. Plasma-extracted cell-free DNA was subjected to whole-genome-based ctDNA analysis. PSMA-positive tumor lesions were delineated and their quantitative parameters extracted. ctDNA and PSMA PET/CT discovery rates were compared, and the prognostic value for overall survival (OS) was evaluated.RESULTS: PSMA PET discovery rates according to castration status and PSA ranges did differ significantly (P = 0.013, P < 0.001), while ctDNA discovery rates did not (P = 0.311, P = 0.123). ctDNA discovery rates differed between localized and metastatic disease (P = 0.013). Correlations between ctDNA concentrations and PSMA-positive tumor volume (PSMA-TV) were significant in all (r = 0.42, P < 0.001) and castration-resistant (r = 0.65, P < 0.001), however not in hormone-sensitive patients (r = 0.15, P = 0.249). PSMA-TV and ctDNA levels were associated with survival outcomes in the Logrank (P < 0.0001, P < 0.0001) and multivariate Cox regression analysis (P = 0.0023, P < 0.0001).CONCLUSION: These findings suggest that PSMA PET imaging outperforms ctDNA analysis in detecting prostate cancer across the whole spectrum of disease, while both modalities are independently highly prognostic for survival outcomes.PMID:38693454 | DOI:10.1007/s00259-024-06698-7
Temporal dynamics of the multi-omic response to endurance exercise training
Nature. 2024 May;629(8010):174-183. doi: 10.1038/s41586-023-06877-w. Epub 2024 May 1.ABSTRACTRegular exercise promotes whole-body health and prevents disease, but the underlying molecular mechanisms are incompletely understood1-3. Here, the Molecular Transducers of Physical Activity Consortium4 profiled the temporal transcriptome, proteome, metabolome, lipidome, phosphoproteome, acetylproteome, ubiquitylproteome, epigenome and immunome in whole blood, plasma and 18 solid tissues in male and female Rattus norvegicus over eight weeks of endurance exercise training. The resulting data compendium encompasses 9,466 assays across 19 tissues, 25 molecular platforms and 4 training time points. Thousands of shared and tissue-specific molecular alterations were identified, with sex differences found in multiple tissues. Temporal multi-omic and multi-tissue analyses revealed expansive biological insights into the adaptive responses to endurance training, including widespread regulation of immune, metabolic, stress response and mitochondrial pathways. Many changes were relevant to human health, including non-alcoholic fatty liver disease, inflammatory bowel disease, cardiovascular health and tissue injury and recovery. The data and analyses presented in this study will serve as valuable resources for understanding and exploring the multi-tissue molecular effects of endurance training and are provided in a public repository ( https://motrpac-data.org/ ).PMID:38693412 | DOI:10.1038/s41586-023-06877-w
Investigation of heat stress responses and adaptation mechanisms by integrative metabolome and transcriptome analysis in tea plants (Camellia sinensis)
Sci Rep. 2024 May 1;14(1):10023. doi: 10.1038/s41598-024-60411-0.ABSTRACTExtreme high temperature has deleterious impact on the yield and quality of tea production, which has aroused the attention of growers and breeders. However, the mechanisms by which tea plant varieties respond to extreme environmental heat is not clear. In this study, we analyzed physiological indices, metabolites and transcriptome differences in three different heat-tolerant tea plant F1 hybrid progenies. Results showed that the antioxidant enzyme activity, proline, and malondialdehyde were significantly decreased in heat-sensitive 'FWS' variety, and the accumulation of reactive oxygen molecules such as H2O2 and O2- was remarkably increased during heat stress. Metabolomic analysis was used to investigate the metabolite accumulation pattern of different varieties in response to heat stress. The result showed that a total of 810 metabolites were identified and more than 300 metabolites were differentially accumulated. Transcriptional profiling of three tea varieties found that such genes encoding proteins with chaperon domains were preferentially expressed in heat-tolerant varieties under heat stress, including universal stress protein (USP32, USP-like), chaperonin-like protein 2 (CLP2), small heat shock protein (HSP18.1), and late embryogenesis abundant protein (LEA5). Combining metabolomic with transcriptomic analyses discovered that the flavonoids biosynthesis pathway was affected by heat stress and most flavonols were up-regulated in heat-tolerant varieties, which owe to the preferential expression of key FLS genes controlling flavonol biosynthesis. Take together, molecular chaperons, or chaperon-like proteins, flavonols accumulation collaboratively contributed to the heat stress adaptation in tea plant. The present study elucidated the differences in metabolite accumulation and gene expression patterns among three different heat-tolerant tea varieties under extreme ambient high temperatures, which helps to reveal the regulatory mechanisms of tea plant adaptation to heat stress, and provides a reference for the breeding of heat-tolerant tea plant varieties.PMID:38693343 | DOI:10.1038/s41598-024-60411-0
MetaboAnalystR 4.0: a unified LC-MS workflow for global metabolomics
Nat Commun. 2024 May 1;15(1):3675. doi: 10.1038/s41467-024-48009-6.ABSTRACTThe wide applications of liquid chromatography - mass spectrometry (LC-MS) in untargeted metabolomics demand an easy-to-use, comprehensive computational workflow to support efficient and reproducible data analysis. However, current tools were primarily developed to perform specific tasks in LC-MS based metabolomics data analysis. Here we introduce MetaboAnalystR 4.0 as a streamlined pipeline covering raw spectra processing, compound identification, statistical analysis, and functional interpretation. The key features of MetaboAnalystR 4.0 includes an auto-optimized feature detection and quantification algorithm for LC-MS1 spectra processing, efficient MS2 spectra deconvolution and compound identification for data-dependent or data-independent acquisition, and more accurate functional interpretation through integrated spectral annotation. Comprehensive validation studies using LC-MS1 and MS2 spectra obtained from standards mixtures, dilution series and clinical metabolomics samples have shown its excellent performance across a wide range of common tasks such as peak picking, spectral deconvolution, and compound identification with good computing efficiency. Together with its existing statistical analysis utilities, MetaboAnalystR 4.0 represents a significant step toward a unified, end-to-end workflow for LC-MS based global metabolomics in the open-source R environment.PMID:38693118 | DOI:10.1038/s41467-024-48009-6
Indices of Nutrition Status of Kidney and Pancreas Transplant Candidates
Transplant Proc. 2024 Apr 30:S0041-1345(24)00182-9. doi: 10.1016/j.transproceed.2024.03.012. Online ahead of print.ABSTRACTNutritional assessment is used to implement early nutritional interventions and reduce complications associated with malnutrition, which plays a crucial role in improving postoperative outcomes for patients undergoing pancreas and/or kidney transplantation.OBJECTIVE: The aim of this study was to analyze the nutritional status (NS) in patients eligible for kidney transplantation (KTx) and simultaneous kidney-pancreas transplantation (SPKTx).METHODS: We analyzed the database of hospitalized patients from 2020 to 2023 to identify preoperative parameters of NS in patients eligible for KTx and SPKTx. A total of 59 patients participated in the study, all of whom were candidates for KTx-23 or SPKTx-36. The study population consisted of 35 women (W) and 24 men (M), with an overall mean age of 44.8 ± 10.2 years (43.5 ± 10.2 years for W and 46.2 ± 10.9 years for M). Both groups included patients on hemodialysis (n = 34) and peritoneal dialysis (n = 12), and patients in the predialysis period (pre-emptive, n = 13). The examined parameters included Onodera's prognostic nutritional index (PNIO), the nutritional risk index (NRI), proper body mass calculated using the Lorenz formula, and the neutrophil-to-lymphocyte ratio (NLR). All patients were assessed according to the NRS 2002 scale.RESULTS: Analysis of the obtained results revealed that the NLR was only one differentiating parameter between Ktx and SPKtx group. Multivariate analysis adjusted for patients' age and gender, comparing quantitative NS indicators was performed. Albumin serum concentration was not dependent on patients' group (KTx/SPKTx) neither age nor gender P = .382. BMI was dependent on patients' age and gender, but not a group (KTx/SPKTx) P = .008. PNIO, NRI, and NRL were not dependent on patients' group (KTx/SPKTx) neither age nor gender.CONCLUSIONS: Additional effort should be devoted to the development of a proper nutrition plan for SPKTx a especially in peritoneal dialysis patients. Toward patients on the waiting list, the regular assessment of nutritional status should be performed which is not a rule in dialysis centers. SPKTx candidates in the perioperative period should receive proper nutrition taking into account their caloric and protein needs.PMID:38692964 | DOI:10.1016/j.transproceed.2024.03.012