PubMed
An acute microglial metabolic response controls metabolism and improves memory
Elife. 2024 Dec 3;12:RP87120. doi: 10.7554/eLife.87120.ABSTRACTChronic high-fat feeding triggers metabolic dysfunction including obesity, insulin resistance, and diabetes. How high-fat intake first triggers these pathophysiological states remains unknown. Here, we identify an acute microglial metabolic response that rapidly translates intake of high-fat diet (HFD) to a surprisingly beneficial effect on metabolism and spatial/learning memory. High-fat intake rapidly increases palmitate levels in cerebrospinal fluid and triggers a wave of microglial metabolic activation characterized by mitochondrial membrane activation and fission as well as metabolic skewing toward aerobic glycolysis. These effects are detectable throughout the brain and can be detected within as little as 12 hr of HFD exposure. In vivo, microglial ablation and conditional DRP1 deletion show that the microglial metabolic response is necessary for the acute effects of HFD. 13C-tracing experiments reveal that in addition to processing via β-oxidation, microglia shunt a substantial fraction of palmitate toward anaplerosis and re-release of bioenergetic carbons into the extracellular milieu in the form of lactate, glutamate, succinate, and intriguingly, the neuroprotective metabolite itaconate. Together, these data identify microglia as a critical nutrient regulatory node in the brain, metabolizing away harmful fatty acids and liberating the same carbons as alternate bioenergetic and protective substrates for surrounding cells. The data identify a surprisingly beneficial effect of short-term HFD on learning and memory.PMID:39625057 | DOI:10.7554/eLife.87120
Mechanism of action of the toxic proline mimic azetidine 2-carboxylic acid in plants
Plant J. 2024 Dec 3. doi: 10.1111/tpj.17154. Online ahead of print.ABSTRACTPlants have an amazing capacity to outcompete neighboring organisms for space and resources. Toxic metabolites are major players in these interactions, which can have a broad range of effectiveness by targeting conserved molecular mechanisms, such as protein biosynthesis. However, lack of knowledge about defensive metabolite pathways, their mechanisms of action, and resistance mechanisms limits our ability to manipulate these pathways for enhanced crop resilience. Nonproteogenic amino acids (NPAAs) are a structurally diverse class of metabolites with a variety of functions but are typically not incorporated during protein biosynthesis. Here, we investigate the mechanism of action of the NPAA azetidine-2-carboxylic acid (Aze), an analog of the amino acid proline (Pro). Using a combination of plate-based assays, metabolite feeding, metabolomics, and proteomics, we show that Aze inhibits the root growth of Arabidopsis and other plants. Aze-induced growth reduction was restored by supplementing L-, but not D-Pro, and nontargeted proteomics confirm that Aze is misincorporated for Pro during protein biosynthesis, specifically on cytosolically translated proteins. Gene expression analysis, free amino acid profiling, and proteomics show that the unfolded protein response is upregulated during Aze treatment implicating that Aze misincorporation results in accumulation of misfolded proteins triggering a global stress response. This study demonstrates the mechanism of action of Aze in plants and provides a foundation for understanding the biological functions of proteotoxic metabolites.PMID:39625042 | DOI:10.1111/tpj.17154
Defects in the H3t Gene Cause an Increase in Leydig Cells With Impaired Spermatogenesis in Mice
Genes Cells. 2024 Dec 3:e13182. doi: 10.1111/gtc.13182. Online ahead of print.ABSTRACTAbnormalities in spermatogenesis, a fundamental component of male reproductive function, can cause male infertility. Somatic cells constituting the testis microenvironment are essential for controlling normal spermatogenesis. Although testicular somatic cells are thought to sense and respond to germ cells to ensure proper spermatogenesis, the details of this signaling mechanism are unknown. Here, we investigated somatic cell dynamics in testicular tissue lacking spermatogenesis using the mice with deletion of the testis-specific histone H3 variant gene H3t. Testicular tissue sections of H3tΔ/Δ mice exhibited an increased interstitial area compared with those of wild-type mice, which was primarily attributed to an increase in Leydig cell numbers. Furthermore, this increase in Leydig cells led to increased testosterone synthesis, which occurred alongside cellular senescence-associated β-galactosidase activity. These findings suggest that Leydig cells monitor the progress of spermatogenesis and possess a mechanism to promote functional germ cell formation.PMID:39624989 | DOI:10.1111/gtc.13182
Maslinic acid induces autophagy and ferroptosis via transcriptomic and metabolomic reprogramming in prostate cancer cells
Front Pharmacol. 2024 Nov 18;15:1453447. doi: 10.3389/fphar.2024.1453447. eCollection 2024.ABSTRACTProstate cancer has the second highest incidence among male malignancies. Only a few studies exist on the inhibitory effects of maslinic acid (MA) on prostate cancer. Herein we found that MA inhibits prostate cancer cell proliferation by decreasing CDK2, CDK4, and CDK6 expression and concurrently increasing p27, Rb, p-Rb expression. Further, MA was observed to induce prostate cancer cell autophagy by increasing the expression of p53, p-p53, ULK1, Beclin1, Atg7, and Atg5 and the ratio of LC3-II/I and concurrently decreasing the expression of ERK1/2 and mTOR. In addition, MA induced RM-1 cell ferroptosis by regulating glutathione, glutamate, and oxidized glutathione concentrations, inhibiting SLC7A11 activity, and downregulating GPX4 expression. Integrated metabolome and transcriptome analysis led to the identification of key pathways (e.g., pathways in cancer and glutathione metabolism). Real-time quantitative PCR confirmed that MA regulates the expression of ABCA1, JUN, and NFKBIA. In vivo, we demonstrated that 50 mg/kg MA significantly inhibited the growth of tumors established using RM-1 cells. To summarize, we report that MA inhibits prostate cancer cell growth both in vitro and in vivo by inducing autophagy and ferroptosis via transcriptomic and metabolomic reprogramming.PMID:39624845 | PMC:PMC11608986 | DOI:10.3389/fphar.2024.1453447
Metabolites Link Intake of a Healthy Diet to Better Insulin and Glucose Homeostasis in the Microbiome and Insulin Longitudinal Evaluation Study (MILES)
Curr Dev Nutr. 2024 Sep 26;8(11):104462. doi: 10.1016/j.cdnut.2024.104462. eCollection 2024 Nov.ABSTRACTBACKGROUND: Dietary quality has been linked to better glycemic control, but the precise molecular mechanisms giving rise to these associations are not fully understood.OBJECTIVES: To examine the association of metabolites associated with the intake of a healthy diet with measures of insulin/glucose homeostasis.METHODS: Using cross-sectional data from 295 United States adults, the associations between 3 diet pattern scores and metabolome-wide metabolites were estimated via linear regression models, which controlled for demographic factors and health behaviors. Subsequently, the associations between the diet-related metabolites with 6 measures of glucose/insulin homeostasis were examined in similar models. A Bonferroni correction was applied to control the family-wise error rate at 5%.RESULTS: Fifty-five metabolites were significantly associated with ≥1 diet score (all P < 1.7∗10-5). When these were summed into each of the 3 diet-specific metabolite summary scores, all 3 aggregate measures showed strong associations with 5 out of 6 measures of glucose/insulin homeostasis (P = 9.7∗10-5-4.1∗10-13).CONCLUSIONS: Adherence to a priori-defined "healthy diet" is associated with the plasma metabolites that, in turn, are associated with better glycemia. If the associations between replicated in future studies and examined using large-scale longitudinal data, the identified molecules could yield insights into mechanisms by which diet may support glucose and insulin homeostasis.PMID:39624807 | PMC:PMC11609643 | DOI:10.1016/j.cdnut.2024.104462
Interplay between Lipids and Complement Proteins-How Multiomics Data Integration Can Help Unravel Age-related Macular Degeneration Pathophysiology: A Proof-of-concept Study
Ophthalmol Sci. 2024 Oct 1;5(1):100629. doi: 10.1016/j.xops.2024.100629. eCollection 2025 Jan-Feb.ABSTRACTOBJECTIVE: Our objectives were to identify correlation patterns between complement and lipid pathways using a multiomics data integration approach and to determine how these interconnections affect age-related macular degeneration (AMD).DESIGN: Nested case-control study.SUBJECTS AND CONTROLS: The analyses were performed in a subset of the Singapore Indian Eye Study. We randomly selected 155 AMD cases and age- and sex-matched them with 155 controls.METHODS: Firstly, a multiomics data integration method was used to identify correlation patterns between the omics data. Then, we tested possible interactions between the lipids and complement proteins using logistic regression models.MAIN OUTCOME MEASURES: Age-related macular degeneration was determined according to the Beckman classification system. We measured in serum samples 35 complement proteins and 66 lipids, and used 9 genetic variants.RESULTS: Among the 155 AMD cases, 93 (60.0%) had early and 62 (40.0%) intermediate AMD. Firstly, we identified 2 clusters between complement proteins and lipids involving (1) mannan-binding lectin serine protease 1 and several different high-density lipoprotein particles, and (2) complement factor H-related protein 1, carboxypeptidase N subunit 2 and complement component C8 gamma chain, and sphingomyelin and different cholesterol. Secondly, we identified 1 interaction between complement protein 1R and sphingomyelin with an odds of AMD 2 times higher for individuals with low levels of sphingomyelin and complement protein 1R (odds ratio = 2.13 [1.09, 4.17]).CONCLUSIONS: We report here, using a cutting-edge multiomics integration approach, the complex interconnections between genetic, metabolomics, and proteomic data. This method permitted us to obtain a holistic picture and identify multiomics signature of AMD pathophysiology. These results advocate for a personalized therapeutic approach that accounts for multiple pathways. However, these results need to be validated in larger studies with different ethnic groups.FINANCIAL DISCLOSURES: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.PMID:39624796 | PMC:PMC11609548 | DOI:10.1016/j.xops.2024.100629
Astragalus polysaccharide alleviates asthma by modulating gut microbiota and serum metabolomics
Biomed Rep. 2024 Nov 13;22(1):12. doi: 10.3892/br.2024.1890. eCollection 2025 Jan.ABSTRACTThe aim of the present study was to examine the effects of Astragalus polysaccharide (APS) on gut microbiota and serum metabolites in asthmatic mice. For this purpose, a total of 36 BALB/c female mice were selected and randomly classified into the following groups: i) The normal control group sensitized with phosphate-buffered saline; ii) the asthma group sensitized and challenged with ovalbumin (OVA); iii) the OVA + APS (2.5 g/kg) treatment group; iv) the OVA + APS (5.0 g/kg) treatment group; v) the OVA + APS (10 g/kg) treatment group; and vi) the OVA + dexamethasone (2 mg/kg) treatment group, with 6 mice in each group. OVA was used to establish the mouse model of asthma. In the APS group, the asthmatic mice were intragastrically administered APS at various doses at 1 h prior to each OVA stimulation. The airway hyperreactivity (AHR) was measured, and hematoxylin and eosin staining was employed to evaluate pulmonary inflammatory infiltration. In addition, 16S rRNA sequencing and ultra-performance liquid chromatography-tandem mass spectrometry were used to detect the changes in the mouse gut microbiota and serum metabolites. The results revealed that compared with the asthma model group, APS improved airway inflammation and eosinophil infiltration in asthmatic mice. In asthmatic mice, the gut microbial imbalance mainly manifested as a low abundance of Bacteroidetes and a high abundance of Firmicutes, yielding an increased F/B ratio. In the high-dose APS group, the abundance of Firmicutes was reduced, and the abundance of Bacteroidetes was increased, which thereby decreased the F/B ratio and corrected the gut microbial imbalance. Through blood metabolomics, 145 and 105 significantly differential metabolites were detected in the medium- and high-dose APS groups, respectively. Moreover, Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis demonstrated that the metabolic pathways in the medium-dose APS group included the biosynthesis of unsaturated fatty acids and the biosynthesis of arginine. On the other hand, the metabolic pathways enriched in high-dose APS group were the biosynthesis of unsaturated fatty acids, and pyrimidine metabolism. On the whole, the present study demonstrates that APS may regulate the gut microbiota and the metabolites to improve airway inflammation and AHR in asthmatic mice.PMID:39624784 | PMC:PMC11609611 | DOI:10.3892/br.2024.1890
Comparative analysis of oral saliva microbiomes and metabolites in Han population at different altitudes
Front Microbiol. 2024 Nov 13;15:1468365. doi: 10.3389/fmicb.2024.1468365. eCollection 2024.ABSTRACTOBJECTIVE: This study investigated the differences in oral saliva microbiota composition and metabolic products among Han Chinese populations living at different altitudes, as well as their correlations.METHOD: The analysis was conducted using the 16S rRNA gene sequencing method and untargeted metabolomics.RESULTS: 16S gene sequencing results showed significant differences in bacterial diversity and composition between HH (High altitude Han) group and LH (Low altitude Han) group. LEfSe analysis showed that Selenomonas, Leptotrichia, Veillonella, Prevotella relatively abundant are higher in HH group, Haemophilus, Neisseria, Actinobacillus, Aggregatibacter are higher in LH group (p<0.05). Furthermore, as depicted in the phylogenetic tree, there are differences observed between the two groups at all taxonomic levels: 4 phyla, 6 classes, 6 orders, 9 families, 9 genera and 8 species (p<0.05). After conducting PICRUSt functional prediction analysis, we identified 11 significantly different KEGG categories (level 2) between the two groups. These categories primarily encompass energy metabolism, amino acid metabolism, and carbohydrate metabolism. Furthermore, non-targeted metabolomics analysis revealed a total of 997 distinct metabolites in the two groups. These differentiated metabolites can be classified into 13 Class I categories including amino acids and their metabolites, benzene and its derivatives, organic acids and their derivatives, heterocyclic compounds, aldehydes, ketones and esters, nucleotides and their metabolites among others. Additionally, fatty acyl compounds, alcohols and amines as well as glycerophospholipids are present along with carbohydrates and other physiologically active components such as hormones. Finally, Pearson correlation analysis of the top 20 differential metabolites with microorganisms demonstrated an interaction between them; however further experimental verification is required to elucidate the specific mechanism of action.CONCLUSION: Therefore, this study revealed the effect of altitude on oral saliva microbes and metabolites, as well as their correlations.PMID:39624722 | PMC:PMC11610449 | DOI:10.3389/fmicb.2024.1468365
Exploring the impact of calcium phosphate biomaterials on cellular metabolism
Heliyon. 2024 Oct 26;10(22):e39753. doi: 10.1016/j.heliyon.2024.e39753. eCollection 2024 Nov 30.ABSTRACTCalcium phosphate (CaP) biomaterials have been widely used in hard tissue engineering, but their impact on cell metabolism is unclear. We synthesized and characterized hydroxyapatite, β-tricalcium phosphate, and biphasic calcium phosphate composites to investigate material effects on NIH/3T3 cell metabolism. The intracellular metabolites were analyzed employing LC-MS metabolomics, and cell metabolic status was assessed comparatively. Our results revealed that CaPs adsorb metabolites, particularly amino acids. Furthermore, CaP biomaterials significantly influence amino acid and energy metabolism pathways. Specifically, we observed glycolysis and TCA cycle activity stimulation, resulting in higher energy consumption in cells adhered to CaP surfaces. Our findings suggest that CaPs composed of different ratios of hydroxyapatite (HAp) and β-tricalcium phosphate (β-TCP) have a similar impact on cell metabolism alterations. Moreover, we observed that the metabolism alterations gradually decreased over time. Our study enhances understanding of cell-CaP interplay, paving the way for metabolic regulation biomaterials and improving efficacy in tissue engineering and regenerative medicine.PMID:39624315 | PMC:PMC11609662 | DOI:10.1016/j.heliyon.2024.e39753
Metabolomic profiles differentiate between porto-sinusoidal vascular disorder, cirrhosis, and healthy individuals
JHEP Rep. 2024 Sep 4;6(12):101208. doi: 10.1016/j.jhepr.2024.101208. eCollection 2024 Dec.ABSTRACTBACKGROUND & AIMS: Porto-sinusoidal vascular disorder (PSVD) is a rare and diagnostically challenging vascular liver disease. This study aimed to identify distinct metabolomic signatures in patients with PSVD or cirrhosis to facilitate non-invasive diagnosis and elucidate perturbed metabolic pathways.METHODS: Serum samples from 20 healthy volunteers (HVs), 20 patients with histologically confirmed PSVD or 20 patients with cirrhosis were analyzed. Metabolites were measured using liquid chromatography-mass spectrometry. Differential abundance was evaluated with Limma's moderated t-statistics. Artificial neural network and support vector machine models were developed to classify PSVD against cirrhosis or HV metabolomic profiles. An independent cohort was used for validation.RESULTS: A total of 283 metabolites were included for downstream analysis. Clustering effectively separated PSVD from HV metabolomes, although a subset of patients with PSVD (n = 5, 25%) overlapped with those with cirrhosis. Differential testing revealed significant PSVD-linked metabolic perturbations, including pertubations in taurocholic and adipic acids, distinguishing patients with PSVD from both HVs and those with cirrhosis. Alterations in pyrimidine, glycine, serine, and threonine pathways were exclusively associated with PSVD. Machine learning models utilizing selected metabolic signatures reliably differentiated the PSVD group from HVs or patients with cirrhosis using only 4 to 6 metabolites. Validation in an independent cohort demonstrated the high discriminative ability of taurocholic acid (AUROC 0.899) for patients with PSVD vs. HVs and the taurocholic acid/aspartic acid ratio (AUROC 0.720) for PSVD vs. cirrhosis.CONCLUSIONS: High-throughput metabolomics enabled the identification of distinct metabolic profiles that differentiate between PSVD, cirrhosis, and healthy individuals. Unique alterations in the glycine, serine, and threonine pathways suggest their potential involvement in PSVD pathogenesis.IMPACT AND IMPLICATIONS: Porto-sinusoidal vascular disorder (PSVD) is a vascular liver disease that can lead to pre-sinusoidal portal hypertension in the absence of cirrhosis, with poorly understood pathophysiology and no established treatment. Our study demonstrates that analyzing the serum metabolome could reveal distinct metabolic signatures in patients with PSVD, including alterations in the pyrimidine, glycine, serine and threonine pathways, potentially shedding light on the disease's underlying pathways. These findings could enable earlier and non-invasive diagnosis of PSVD, potentially reducing reliance on invasive procedures like liver biopsy and guiding diagnostic pathways.PMID:39624234 | PMC:PMC11609546 | DOI:10.1016/j.jhepr.2024.101208
Fra-1 affects chemotherapy sensitivity by inhibiting ferroptosis in gastric cancer cells
Cancer Drug Resist. 2024 Nov 16;7:44. doi: 10.20517/cdr.2024.101. eCollection 2024.ABSTRACTAim: Gastric cancer (GC) is one of the common malignant tumors, and most patients with advanced GC often develop chemotherapy resistance, resulting in poor chemotherapy efficacy. Therefore, it is crucial to clarify the specific mechanisms of their chemotherapy resistance. Methods: In this study, we analyzed the correlation between fos-related antigen-1 (Fra-1) and chemotherapy resistance in GC using bioinformatics, cell counting kit-8 (CCK8), and 5-ethynyl-2'-deoxyuridine (EDU) combined with flow cytometry; furthermore, we used energy metabolomics sequencing, combined with ChIP-qPCR technology, to elucidate the specific role of Fra-1 in chemotherapy resistance of GC cells and its related mechanisms. Results: We found that high Fra-1 expression was closely related to chemotherapeutic drugs in GC cells, as demonstrated by bioinformatics analysis combined with EDU and CCK8 experiments. Energy metabolomics combined with in vitro cellular experimental analysis revealed that the pentose phosphate pathway (PPP) was activated in GC cells with high Fra-1 expression, along with an increase in the synthesis of metabolites such as nicotinamide adenine dinucleotide phosphate (NADPH) and glutathione (GSH), a decrease in the level of reactive oxygen species (ROS), and the inhibition of their ferroptosis. In addition, ChIP-qPCR experiments confirmed that Fra-1 binds to the promoter of glucose-6-phosphate dehydrogenase (G6PD), a key rate-limiting enzyme of the PPP, and transcriptionally regulates its expression, which in turn activates the PPP and promotes chemotherapy resistance in GC cells. Conclusion: Our research findings suggest that Fra-1 activates the PPP by upregulating G6PD transcriptional activity and inhibiting its ubiquitination level, inhibiting ferroptosis in GC cells and inducing chemoresistance. This provides an experimental basis for screening potential molecular targets for chemotherapy resistance in GC patients.PMID:39624082 | PMC:PMC11609144 | DOI:10.20517/cdr.2024.101
Multi-omics insights into the pathogenesis of diabetic cardiomyopathy: epigenetic and metabolic profiles
Epigenomics. 2024 Dec 2:1-16. doi: 10.1080/17501911.2024.2435257. Online ahead of print.ABSTRACTAIM: Diabetic cardiomyopathy (DbCM), a complex metabolic disease, greatly threatens human health due to therapeutic limitations. Multi-omics approaches facilitate the elucidation of its intrinsic pathological changes.METHODS: Metabolomics, RNA-seq, proteomics, and assay of transposase-accessible chromatin (ATAC-seq) were utilized to elucidate multidimensional molecular alterations in DbCM.RESULTS: In the heart and plasma of mice with DbCM, metabolomic analysis demonstrated significant differences in branched-chain amino acids (BCAAs) and lipids. Subsequent RNA-seq and proteomics showed that the key genes, including BCKDHB, PPM1K, Cpt1b, Fabp4, Acadm, Acadl, Acadvl, HADH, HADHA, HADHB, Eci1, Eci2, PDK4, and HMGCS2, were aberrantly regulated, contributing to the disorder of BCAAs and fatty acids. ATAC-seq analysis underscored the pivotal role of epigenetic regulation by revealing dynamic shifts in chromatin accessibility and a robust positive correlation with gene expression patterns in diabetic cardiomyopathy mice. Furthermore, motif analysis identified that KLF15 as a critical transcription factor in DbCM, regulating the core genes implicated with BCAAs metabolism.CONCLUSION: Our research delved into the metabolic alterations and epigenetic landscape and revealed that KLF15 may be a promising candidate for therapeutic intervention in DbCM.PMID:39623870 | DOI:10.1080/17501911.2024.2435257
The Turnip Yellows Virus Capsid Protein Promotes Access of Its Main Aphid Vector Myzus persicae to Phloem Tissues
Plant Cell Environ. 2024 Dec 2. doi: 10.1111/pce.15303. Online ahead of print.ABSTRACTMany plant viruses modify the phenotype of their hosts, which may influence the behaviour of their vectors and facilitate transmission. Among them is the turnip yellows virus (TuYV), which can modify the orientation, feeding, and performance of its main aphid vector, Myzus persicae. However, the virus factors driving these mechanisms have not been elucidated. In this study, we compared the feeding behaviour and fecundity of aphids on TuYV-infected and transgenic Arabidopsis thaliana expressing individual TuYV proteins (CP, RT and P0) to define the role of these proteins in aphid-plant interactions. Aphids on TuYV-infected plants had shorter pathway phases and ingested phloem sap for longer times, which is expected to promote the acquisition of the phloem-limited TuYV. No change in aphid fecundity was observed on TuYV-infected plants. The transmission-conducive feeding behaviour changes could be fully reproduced by phloem-specific expression of the capsid protein (CP) in transgenic plants, whereas expression of P0 had minor and RT had no effects on aphid feeding behaviour. We then carried out a metabolomic analysis to determine plant compounds that could be involved in the modification of the aphid behaviour. A few metabolites were specific for TuYV-infected or CP-transgenic A. thaliana, and are good candidates for inducing behavioural changes.PMID:39623721 | DOI:10.1111/pce.15303
Nicotinamide N-methyltransferase negatively regulates metastasis-promoting property of cancer-associated fibroblasts in lung adenocarcinoma
Cancer Commun (Lond). 2024 Dec 2. doi: 10.1002/cac2.12633. Online ahead of print.ABSTRACTBACKGROUND: Recurrence and metastasis remain significant challenges in lung adenocarcinoma (LUAD) after radical resection. The mechanisms behind the recurrence and metastasis of LUAD remain elusive, and deregulated cellular metabolism is suspected to play a significant role. This study explores the metabolic and epigenetic regulation mediated by nicotinamide N-methyl transferase (NNMT) in LUAD.METHODS: Untargeted metabolomic analyses were performed to detect metabolism irregularities. Single-cell RNA sequencing (RNA-seq) databases and multiplex immunofluorescence analysis were used to identify the location of NNMT within the tumor microenvironment. The biological functions of NNMT were investigated both in vitro and in vivo, with RNA-seq and chromatin immunoprecipitation-PCR providing insights into underlying mechanisms. Finally, single-cell RNA-seq data and immunohistochemistry of primary tumors were analyzed to validate the main findings.RESULTS: Untargeted metabolomic analyses revealed metabolic aberrations in amino acids, organic acids, lipids, and nicotinamide pathways, which are linked to metastasis of non-small cell lung cancer. NNMT is a key enzyme in nicotinamide metabolism, and we found the bulk tissue mRNA level of NNMT gene was inversely associated with LUAD metastasis. NNMT was proved to be predominantly expressed in cancer-associated fibroblasts (CAFs) within the stromal regions of LUAD, and a low stromal NNMT expression was identified as a predictor of poor disease-free survival following radical resection of LUAD. The isolation and primary culture of CAFs from LUAD enabled in vitro and in vivo experiments, which confirmed that NNMT negatively regulated the metastasis-promoting properties of CAFs in LUAD. Mechanistically, the downregulation of NNMT led to an increase in intracellular methyl groups by reducing the activity of the methionine cycle, resulting in heightened methylation at H3K4me3. This alteration triggered the upregulation of genes involved in extracellular matrix remodeling in CAFs, including those encoding collagens, integrins, laminins, and matrix metalloproteinases, thereby facilitating cancer cell invasion and metastasis. Reanalysis of single-cell RNA-seq data and immunohistochemistry assays of primary LUAD tissues substantiated NNMT's negative regulation of these genes in CAFs.CONCLUSIONS: This study provides novel insights into the metabolic and epigenetic regulatory functions of NNMT in CAFs, expanding the current understanding of LUAD metastasis regulation and suggesting potential avenues for future research and therapeutic development.PMID:39623600 | DOI:10.1002/cac2.12633
Role of metabolic reprogramming-mediated hepatic stellate cell activation in the pathogenesis of hepatic fibrosis
Zhonghua Gan Zang Bing Za Zhi. 2024 Nov 20;32(11):1053-1056. doi: 10.3760/cma.j.cn501113-20240223-00088.ABSTRACTThe activation of hepatic stellate cells (HSCs) and excessive deposition of extracellular matrix are the keys to the occurrence and development of liver fibrosis. Metabolic reprogramming supports the activation process of HSCs, which requires substantial energy to meet the corresponding energy requirements for liver fibrosis formation. This review focuses on the effect of metabolomic changes characterized by metabolic reprogramming on HSC activation and summarizes the characteristics of HSC energy metabolism reprogramming during the formation of liver fibrosis, with the aim to summarize research evidence for exploring the mechanism and developing strategies for the prevention and treatment of liver fibrosis.PMID:39623584 | DOI:10.3760/cma.j.cn501113-20240223-00088
Unraveling the role of gut microbiome in predicting adverse events in neoadjuvant therapy for rectal cancer
Hum Vaccin Immunother. 2024 Dec 31;20(1):2430087. doi: 10.1080/21645515.2024.2430087. Epub 2024 Dec 2.ABSTRACTSome patients may develop adverse events during neoadjuvant chemoradiotherapy combined with immunotherapy, influencing response rates. The roles of intestinal microbiome and its metabolites in therapeutic adverse events remain unclear. We collected baseline fecal samples from 21 patients with adverse events (AE group) and 11 patients without adverse events (Non-AE group). Their microbiota and metabolome were characterized using metagenomic shotgun sequencing and untargeted metabolomics. At the species level, the gut microbiota in the Non-AE group exhibits significantly higher abundance of Clostridium sp. Alistipes sp. and lower abundance of Lachnoclostridium sp. Weissella cibaria, Weissella confusa, compared to the AE group (p < .05). A total of 58 discriminative metabolites were identified between groups. Beta-alanine metabolism was scattered. Boc-beta-cyano-L-alanine and CoQ9 were significantly increased in patients without adverse events, while linoleic acid increased in patients with adverse events. The increased Alistipes sp. in the Non-AE group was positively correlated with Boc-beta-cyano-L-alanine and negatively correlated with linoleic acid (p < .05). We constructed a combined microbiome-metabolite model to distinguish Non-AE and AE patients with an AUC of 0.963 via the random forest algorithm. Our findings provided a novel insight into the interplay of multispecies microbial cluster and metabolites of rectal patients with adverse events in neoadjuvant chemoradiotherapy combined with immunotherapy. These microbiota and metabolites deserve further investigations to reveal their roles in adverse events, providing clues for better treatment scenarios.Trial registration number: ClinicalTrials.gov identifier: NCT05368051.PMID:39623529 | DOI:10.1080/21645515.2024.2430087
Pivotal Role of Mass Spectrometry for the Assessment of Exposure to Reactive Chemical Contaminants: From the Exposome to the Adductome
Mass Spectrom Rev. 2024 Dec 2. doi: 10.1002/mas.21917. Online ahead of print.ABSTRACTA large part of the Human chemical exposome is now well characterized, and its health effects has been widely documented, although precise causal links remain difficult to establish. In parallel, genetic factors only were shown to contribute less than 30% to various pathologies. Therefore, environmental factors may represent the predominant cause of chronic diseases. Mass Spectrometry has been established for many years as a main "gold standard" in this field due to its performances both in sensitivity and selectivity. However, some unstable or highly reactive compounds may escape their detection in the biological samples because of their short half-life although some of their stable metabolites, if any, can be used for the exposure assessment. These electrophilic molecules are known to bind covalently to nucleophilic molecules in the body to form what are commonly called adducts. The study of adducts formed with DNA, proteins or with glutathione, nowadays called adductomics, can provide additional toxicologically relevant information in biomonitoring studies. This review describes this particular part of the reactive exposome and the related mass spectrometric methods developed therein. Three dedicated parts of this review are devoted to the contribution of mass spectrometry respectively to the assessment of DNA modifications, protein modifications, and reaction with glutathione.PMID:39623480 | DOI:10.1002/mas.21917
Associations Between Skin Microbiome and Metabolome in the Pathogenesis of Atopic Dermatitis Patients With Scalp Involvement
Allergy Asthma Immunol Res. 2024 Nov;16(6):668-681. doi: 10.4168/aair.2024.16.6.668.ABSTRACTPURPOSE: Atopic dermatitis (AD) is a chronic inflammatory skin condition influenced by various factors, such as the skin microbiome and metabolome. However, specific contributions of these factors to scalp involvement in AD still need to be explored. In this study, we aimed to assess the associations between the skin microbiome and metabolome in AD patients with scalp dermatitis and healthy controls (HCs).METHODS: A total of 20 AD patients with scalp involvement and 16 HCs were recruited, and their skin samples were collected for analysis. Bioinformatic analysis and 16S rRNA metagenomic sequencing were performed, with gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) conducted for AD-associated skin metabolites. Spearman correlation analysis was used to identify the correlations between AD-associated skin bacteria and metabolites.RESULTS: The results revealed significant differences in bacterial taxa and metabolites between the lesional and non-lesional scalp skin samples of AD patients (groups LS and NL, respectively) and those of HCs (group HC). Notably, group LS showed a significantly increased relative abundance of the genus Staphylococcus and a decreased abundance of Cutibacterium compared to group HC. The reduced abundance of Cutibacterium was also observed when comparing LS to NL. The GC-TOF-MS analysis identified 33 significantly decreased metabolites and 17 significantly increased metabolites in groups LS and NL compared with group HC. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that amino acid-related metabolism was significantly altered in the metabolic pathway between groups LS, NL, and HC. Furthermore, Spearman correlation analysis showed significant correlations of the altered bacteria genera and skin metabolites between the 3 groups.CONCLUSIONS: The results of this research provide valuable insights into the associations the skin microbiome and metabolome between groups LS, NL, and HC. Identifying these specific contributions may offer new avenues for understanding the pathogenesis of scalp involvement in AD patients and potentially lead to improving management strategies.PMID:39622690 | DOI:10.4168/aair.2024.16.6.668
Endometrial Cancer Research Based on Gut Microbiomics and Metabolomics: An Analysis of Correlation and Differences
Biomed Environ Sci. 2024 Oct 20;37(10):1204-1207. doi: 10.3967/bes2024.145.NO ABSTRACTPMID:39622669 | DOI:10.3967/bes2024.145
Blocking adipocyte YY1 decouples thermogenesis from beneficial metabolism by promoting spermidine production
Diabetes. 2024 Dec 2:db240501. doi: 10.2337/db24-0501. Online ahead of print.ABSTRACTThe accumulation of mitochondria in thermogenic adipose tissue (i.e., brown and beige fat) increases energy expenditure, which can aid in alleviating obesity and metabolic disorders. However, recent studies have shown that knocking out key proteins required to maintain mitochondrial function inhibits the energy expenditure in thermogenic fat, and yet the knockout mice are unexpectedly protected from developing obesity or metabolic disorders when fed a high-fat diet (HFD). In the present study, non-biased sequencing-based screening revealed the importance of YY1 in the transcription of electron transport chain genes and the enhancement of mitochondrial function in thermogenic adipose tissue. Specifically, adipocyte YY1 null (YAKO) mice showed lower energy expenditure and were intolerant to cold stress. Interestingly, YAKO mice showed alleviation of HFD-induced metabolic disorders, which can be attributed to a suppression of adipose tissue inflammation. Metabolomic analysis revealed that blocking YY1 directed glucose metabolism toward lactate, enhanced the uptake of glutamine, and promoted the production of anti-inflammatory spermidine. Conversely, blocking spermidine production in YAKO mice reversed their resistance to HFD-induced disorders. Thus, although blocking adipocyte YY1 impairs the thermogenesis, it promotes spermidine production and alleviates adipose tissue inflammation, therefore leads to an uncoupling of adipose tissue energy expenditure from HFD-induced metabolic disorders.PMID:39621859 | DOI:10.2337/db24-0501