PubMed

Arthritis Rheumatol. 2023 Oct 6. doi: 10.1002/art.42724. Online ahead of print.ABSTRACTOBJECTIVE: Investigate the hypothesis that interferon (IFN) stimulated gene (ISG) expression in systemic lupus erythematosus (SLE) monocytes is linked to changes in metabolic reprogramming and epigenetic regulation of ISG expression.METHODS: Monocytes from healthy volunteers and SLE patients at baseline or following IFNα treatment were analyzed by extracellular flux analysis, proteomics, metabolomics, chromatin immunoprecipitation and gene expression. The histone demethylases KDM6A/B were inhibited using GSK-J4. GSK-J4 was tested in pristane and resiquimod (R848) models of IFN-driven SLE.RESULTS: SLE monocytes had enhanced rates of glycolysis and oxidative phosphorylation compared to healthy control (HC) monocytes, as well as increased levels of isocitrate dehydrogenase (IDH2) and its product, α-ketoglutarate (α-KG). As α-KG is a required cofactor for histone demethylases KDM6A and KDM6B, we hypothesized that IFNα may be driving 'trained immune' responses through altering histone methylation. IFNα priming (day 1) resulted in a sustained increase in the expression of ISGs in primed cells (day 5) and enhanced expression on restimulation with IFNα. Importantly decreased H3K27 trimethylation was observed at the promoters of ISGs following IFNα priming. Finally, GSK-J4 (KDM6A/B inhibitor) resulted in decreased ISG expression in SLE patient monocytes, as well as reduced autoantibody production, ISG expression and kidney pathology in R848-treated Balb/c mice.CONCLUSION: Our study suggests chronic IFNα exposure alters epigenetic regulation of ISG expression in SLE monocytes via changes in immunometabolism, a mechanism reflecting trained immunity to type I IFN. Importantly, it opens the possibility that targeting histone modifying enzymes such as KDM6A/B may reduce IFN responses in SLE.PMID:37800478 | DOI:10.1002/art.42724

Front Immunol. 2023 Sep 20;14:1250762. doi: 10.3389/fimmu.2023.1250762. eCollection 2023.ABSTRACTAdenine nucleotides (AN) are ubiquitous metabolites that regulate cellular energy metabolism and modulate cell communication and inflammation. To understand how disturbances in AN balance arise and affect cellular function, robust quantification techniques for these metabolites are crucial. However, due to their hydrophilicity, simultaneous quantification of AN across various biological samples has been challenging. Here we present a hydrophilic interaction high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) based method for the quantification of 26 adenosine nucleotides and precursors as well as metabolic products of nicotinamide adenine dinucleotide (NAD) in plasma, liver, and adipose tissue samples as well as cell culture supernatants and cells. Method validation was performed with regard to linearity, accuracy, precision, matrix effects, and carryover. Finally, analysis of cell culture supernatants derived from intestinal organoids and RAW 264.7 cells illustrates that the here described method is a reliable and easy-to-use tool to quantify AN and opens up new avenues to understand the role of AN generation and breakdown for cellular functions.PMID:37799723 | PMC:PMC10548204 | DOI:10.3389/fimmu.2023.1250762

Front Microbiol. 2023 Sep 20;14:1195709. doi: 10.3389/fmicb.2023.1195709. eCollection 2023.ABSTRACTFlammulina filiformis, a typical agaric fungus, is a widely cultivated and consumed edible mushroom. Elongation of its stipe (as the main edible part) is closely related to its yield and commercial traits; however, the endogenous hormones during stipe elongation and their regulatory mechanisms are not well understood. Gibberellin (GA) plays an important role in the regulation of plant growth, but little has been reported in macro fungi. In this study, we first treated F. filiformis stipes in the young stage with PBZ (an inhibitor of GA) and found that PBZ significantly inhibited elongation of the stipe. Then, we performed GA-targeted metabolome and transcriptome analyses of the stipe at both the young and elongation stages. A total of 13 types of GAs were detected in F. filiformis; the contents of ten of them, namely, GA3, GA4, GA8, GA14, GA19, GA20, GA24, GA34, GA44, and GA53, were significantly decreased, and the contents of three (GA5, GA9, and GA29) were significantly increased during stipe elongation. Transcriptome analysis showed that the genes in the terpenoid backbone biosynthesis pathway showed varying expression patterns: HMGS, HMGR, GPS, and FPPS were significantly upregulated, while CPS/KS had no significant difference in transcript level during stipe elongation. In total, 37 P450 genes were annotated to be involved in GA biosynthesis; eight of them were upregulated, twelve were downregulated, and the rest were not differentially expressed. In addition, four types of differentially expressed genes involved in stipe elongation were identified, including six signal transduction genes, five cell cycle-controlling genes, twelve cell wall-related enzymes and six transcription factors. The results identified the types and content of GAs and the expression patterns of their synthesis pathways during elongation in F. filiformis and revealed the molecular mechanisms by which GAs may affect the synthesis of cell wall components and the cell cycle of the stipe through the downstream action of cell wall-related enzymes, transcription factors, signal transduction and cell cycle control, thus regulating stipe elongation. This study is helpful for understanding the roles of GAs in stipe development in mushrooms and lays the foundation for the rational regulation of stipe length in agaric mushrooms during production.PMID:37799602 | PMC:PMC10548271 | DOI:10.3389/fmicb.2023.1195709

Front Plant Sci. 2023 Sep 19;14:1255682. doi: 10.3389/fpls.2023.1255682. eCollection 2023.ABSTRACTThe lack of irrigation water in agricultural soils poses a significant constraint on global crop production. In-depth investigation into microRNAs (miRNAs) has been widely used to achieve a comprehensive understanding of plant defense mechanisms. However, there is limited knowledge on the association of miRNAs with drought tolerance in cigar tobacco. In this study, a hydroponic experiment was carried out to identify changes in plant physiological characteristics, miRNA expression and metabolite profile under drought stress, and examine the mitigating effects of selenium (Se) application. The shoot dry weight of drought-stressed plants was approximately half (50.3%) of that in non-stressed (control) conditions. However, plants supplied with Se attained 38.8% greater shoot dry weight as compared to plants with no Se supply under drought stress. Thirteen miRNAs were identified to be associated with drought tolerance. These included 7 known (such as nta-miR156b and nta-miR166a) and 6 novel miRNAs (such as novel-nta-miR156-5p and novel-nta-miR209-5p) with the target genes of squamosa promoter-binding-like protein 4 (SPL4), serine/threonine protein phosphatase 2A (PPP2A), cation/calcium exchanger 4-like (CCX4), extensin-1-like (EXT1) and reduced wall acetylation 2 (RWA2). Further investigation revealed that the expression levels of Ext1 and RWA2 were significantly decreased under drought stress but increased with Se addition. Moreover, key metabolites such as catechin and N-acetylneuraminic acid were identified, which may play a role in the regulation of drought tolerance. The integrated analysis of miRNA sequencing and metabolome highlighted the significance of the novel-nta-miR97-5p- LRR-RLK- catechin pathway in regulating drought tolerance. Our findings provide valuable insights into the molecular mechanisms underlying drought tolerance and Se-induced stress alleviation in cigar tobacco.PMID:37799555 | PMC:PMC10548829 | DOI:10.3389/fpls.2023.1255682

Front Oncol. 2023 Sep 18;13:1289397. doi: 10.3389/fonc.2023.1289397. eCollection 2023.NO ABSTRACTPMID:37799477 | PMC:PMC10548817 | DOI:10.3389/fonc.2023.1289397

Acta Pharm Sin B. 2023 Oct;13(10):4273-4290. doi: 10.1016/j.apsb.2023.07.011. Epub 2023 Jul 15.ABSTRACTDuring the development of therapeutic microRNAs (miRNAs or miRs), it is essential to define their pharmacological actions. Rather, miRNA research and therapy mainly use miRNA mimics synthesized in vitro. After experimental screening of unique recombinant miRNAs produced in vivo, three lead antiproliferative miRNAs against human NSCLC cells, miR-22-3p, miR-9-5p, and miR-218-5p, were revealed to target folate metabolism by bioinformatic analyses. Recombinant miR-22-3p, miR-9-5p, and miR-218-5p were shown to regulate key folate metabolic enzymes to inhibit folate metabolism and subsequently alter amino acid metabolome in NSCLC A549 and H1975 cells. Isotope tracing studies further confirmed the disruption of one-carbon transfer from serine to folate metabolites by all three miRNAs, inhibition of glucose uptake by miR-22-3p, and reduction of serine biosynthesis from glucose by miR-9-5p and -218-5p in NSCLC cells. With greater activities to interrupt NSCLC cell respiration, glycolysis, and colony formation than miR-9-5p and -218-5p, recombinant miR-22-3p was effective to reduce tumor growth in two NSCLC patient-derived xenograft mouse models without causing any toxicity. These results establish a common antifolate mechanism and differential actions on glucose uptake and metabolism for three lead anticancer miRNAs as well as antitumor efficacy for miR-22-3p nanomedicine, which shall provide insight into developing antimetabolite RNA therapies.PMID:37799388 | PMC:PMC10547963 | DOI:10.1016/j.apsb.2023.07.011

Parasit Vectors. 2023 Oct 5;16(1):346. doi: 10.1186/s13071-023-05970-3.ABSTRACTBACKGROUND: Schistosoma infection is a significant public health issue, affecting over 200 million individuals and threatening 700 million people worldwide. The species prevalent in China is Schistosoma japonicum. Recent studies showed that both gut microbiota and metabolome are closely related to schistosomiasis caused by S. japonicum, but clinical study is limited and the underlying mechanism is largely unclear. This study aimed to explore alterations as well as function of gut microbiota and metabolite profile in the patients with S. japonicum infection.METHODS: This study included 20 patients diagnosed with chronic schistosomiasis caused by S. japonicum, eight patients with advanced schistosomiasis caused by S. japonicum and 13 healthy volunteers. The fresh feces of these participators, clinical examination results and basic information were collected. 16S ribosomal RNA gene sequencing was used to investigate gut microbiota, while ultraperformance liquid chromatography-mass spectrometry (UHPLC-MS) was applied to explore the metabolome of patients in different stages of schistosomiasis.RESULTS: The study found that gut microbiota and metabolites were altered in patients with different stages of S. japonicum infection. Compared with healthy control group, the gut microbial diversity in patients with chronic S. japonicum infection was decreased significantly. However, the diversity of gut microbiota in patients with chronic schistosomiasis was similar to that in patients with advanced schistosomiasis. Compared with uninfected people, patients with schistosomiasis showed decreased Firmicutes and increased Proteobacteria. As disease progressed, Firmicutes was further reduced in patients with advanced S. japonicum infection, while Proteobacteria was further increased. In addition, the most altered metabolites in patients with S. japonicum infection were lipids and lipid-like molecules as well as organo-heterocyclic compounds, correlated with the clinical manifestations and disease progress of schistosomiasis caused by S. japonicum.CONCLUSIONS: This study suggested that the gut microbiota and metabolome altered in patients in different stages of schistosomiasis, which was correlated with progression of schistosomiasis caused by S. japonicum. This inter-omics analysis may shed light on a better understanding of the mechanisms of the progression of S. japonicum infection and contribute to identifying new potential targets for the diagnosis and prognosis of S. japonicum infection. However, a large sample size of validation in clinic is needed, and further study is required to investigate the underlying mechanism.PMID:37798771 | DOI:10.1186/s13071-023-05970-3

Nat Metab. 2023 Oct 5. doi: 10.1038/s42255-023-00890-z. Online ahead of print.ABSTRACTNeuronal activity creates an intense energy demand that must be met by rapid metabolic responses. To investigate metabolic adaptations in the neuron-enriched dentate granule cell (DGC) layer within its native tissue environment, we employed murine acute hippocampal brain slices, coupled with fast metabolite preservation and followed by mass spectrometry (MS) imaging, to generate spatially resolved metabolomics and isotope-tracing data. Here we show that membrane depolarization induces broad metabolic changes, including increased glycolytic activity in DGCs. Increased glucose metabolism in response to stimulation is accompanied by mobilization of endogenous inosine into pentose phosphates via the action of purine nucleotide phosphorylase (PNP). The PNP reaction is an integral part of the neuronal response to stimulation, because inhibition of PNP leaves DGCs energetically impaired during recovery from strong activation. Performing MS imaging on brain slices bridges the gap between live-cell physiology and the deep chemical analysis enabled by MS.PMID:37798473 | DOI:10.1038/s42255-023-00890-z

Sci Rep. 2023 Oct 5;13(1):16811. doi: 10.1038/s41598-023-43664-z.ABSTRACTFor end-stage kidney disease (ESKD) patients, hemodialysis requires durable vascular access which is often surgically created using an arteriovenous fistula (AVF). However, some ESKD patients that undergo AVF placement develop access-related hand dysfunction (ARHD) through unknown mechanisms. In this study, we sought to determine if changes in the serum metabolome could distinguish ESKD patients that develop ARHD from those that have normal hand function following AVF creation. Forty-five ESKD patients that underwent first-time AVF creation were included in this study. Blood samples were obtained pre-operatively and 6-weeks post-operatively and metabolites were extracted and analyzed using nuclear magnetic resonance spectroscopy. Patients underwent thorough examination of hand function at both timepoints using the following assessments: grip strength manometry, dexterity, sensation, motor and sensory nerve conduction testing, hemodynamics, and the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire. Nineteen of the forty-five patients displayed overt weakness using grip strength manometry (P < 0.0001). Unfortunately, the serum metabolome was indistinguishable between patients with and without weakness following AVF surgery. However, a significant correlation was found between the change in tryptophan levels and the change in grip strength suggesting a possible role of tryptophan-derived uremic metabolites in post-AVF hand-associated weakness. Compared to grip strength, changes in dexterity and sensation were smaller than those observed in grip strength, however, post-operative decreases in phenylalanine, glycine, and alanine were unique to patients that developed signs of motor or sensory disability following AVF creation.PMID:37798334 | DOI:10.1038/s41598-023-43664-z

J Ethnopharmacol. 2023 Oct 3:117274. doi: 10.1016/j.jep.2023.117274. Online ahead of print.ABSTRACTETHNOPHARMACOLOGICAL RELEVANCE: Inonotus hispidus is the traditional Chinese medicine Sanghuang. Since ancient times, Sanghuang has been documented to be used in the treatment of female breast diseases. However, the pharmacological mechanism of Sanghuang in the treatment of mammary gland hyperplasia (HMG) remains unclear.AIM OF THE STUDY: The ethyl acetate extract of the aging fruiting body of I. hispidus (IEAE) was used to study the pharmacological mechanism of IEAE in the treatment of HMG using non-targeted metabolomics.MATERIALS AND METHODS: The HMG rat model was established, and serum metabolomics was used to study the potential therapeutic mechanism of IEAE for HMG.RESULTS: IEAE has obvious therapeutic effect on HMG model rats, and no obvious adverse reactions were observed. Non-targeted metabolomics showed that after IEAE intervention, the upstream metabolite D-erythrose 4-phosphate was significantly downregulated, aromatic amino acids such as tryptophan, tyrosine, and phenylalanine were downregulated, and the downstream metabolites N-acetyl-L-glutamate and L-proline were significantly upregulated. After an intervention with yakuchinone A, non-targeted metabolomics analyses demonstrated that yakuchinone A restored tetrahydrocorticosterone, cortisol, and etiocholanolone to normal levels, estriol was significantly upregulated, and steroid hormone biosynthesis was significantly activated.CONCLUSION: IEAE was shown to have a good therapeutic effect on HMG in a rat model without adverse reactions. The mechanism of action was mainly based on the biosynthesis of amino acids. Small molecule metabolites such as D-erythrose 4-phosphate, N-acetyl-L-glutamate, and L-proline may be potential targets for IEAE in the treatment of HMG. Yakuchinone A is one of the main active components of IEAE, and plays a role by promoting the steroid hormone biosynthesis pathway. Estriol may be a potential target for the treatment of HMG with yakuchinone A, providing a new concept for clinical treatment of HMG.PMID:37797875 | DOI:10.1016/j.jep.2023.117274

Exp Eye Res. 2023 Oct 3:109672. doi: 10.1016/j.exer.2023.109672. Online ahead of print.ABSTRACTLewisite (LEW) is an arsenical vesicant that can be a potentially dangerous chemical warfare agent (CWA). Eyes are particularly susceptible to vesicant induced injuries and ocular LEW exposure can act swiftly, causing burning of eyes, edema, inflammation, cell death and even blindness. In our previous studies, we developed a LEW exposure-induced corneal injury model in rabbit and showed increased inflammation, neovascularization, cell death, and structural damage to rabbit corneas upon LEW exposure. In the present study, we further assessed the metabolomic changes to delineate the possible mechanisms underlying the LEW-induced corneal injuries. This information is vital and could help the development of effective targeted therapies against ocular LEW injuries. Thus, the metabolomic changes associated with LEW exposures in rabbit corneas were assessed as a function of time, to delineate pathways from molecular perturbations at the genomic and proteomic levels. New Zealand white rabbit corneas (n = 3-6) were exposed to LEW vapor (0.2 mg/L; flow rate: 300 ml/min) for 2.5 min (short exposure; low dose) or 7.5 min (long-exposure; high dose) and then collected at 1, 3, 7, or 14 days post LEW exposure. Samples were prepared using the automated MicroLab STAR® system, and proteins precipitated to recover the chemically diverse metabolites. Metabolomic analysis was carried out by reverse phase UPLC-MS/MS and gas chromatography (GC)-MS. The data obtained were analyzed using Metabolon's software. The results showed that LEW exposures at high doses were more toxic, particularly at the day 7 post exposure time point. LEW exposure was shown to dysregulate metabolites associated with all the integral functions of the cornea and cause increased inflammation and immune response, as well as generate oxidative stress. Additionally, all important metabolic functions of the cells were also affected: lipid and nucleotide metabolism, and energetics. The high dose LEW exposures were more toxic, particularly at day 7 post LEW exposure (>10-fold increased levels of histamine, quinolinate, N-acetyl-β-alanine, GMP, and UPM). LEW exposure dysregulated integral functions of the cornea, caused inflammation and heightened immune response, and generated oxidative stress. Lipid and nucleotide metabolism, and energetics were also affected. The novel information about altered metabolic profile of rabbit cornea following LEW exposure could assist in delineating complex molecular events; thus, aid in identifying therapeutic targets to effectively ameliorate ocular trauma.PMID:37797797 | DOI:10.1016/j.exer.2023.109672

Fitoterapia. 2023 Oct 3:105695. doi: 10.1016/j.fitote.2023.105695. Online ahead of print.ABSTRACTFor centuries, food, herbal medicines, and natural products have been valuable resources for discovering novel antiviral drugs, uncovering new structure-activity relationships, and developing effective strategies to prevent/treat viral infections. One such resource is Phellinus linteus, a mushroom used in folk medicine in Taiwan, Japan, Korea, and China. In this rich historical context, the key metabolites of Phellinus linteus mycelia ethanolic extract (GKPL) impacting the entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at multiple stages have yet to be explored. Thus, this study systematically identifies and assesses the inhibitory effect of GKPL on the SARS-CoV-2 virus. Initially, the concentrations and contact times of GKPL against SARS-CoV-2 pseudovirus were assessed in HepG2 cells. Subsequently, utilizing the Ultra Performance Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry method, potential biomarkers in the fungal extract were discerned. Metabolomic analysis identified 18 compounds in GKPL, with hispidin and hypholomine B present in the highest amounts. These compounds were isolated using chromatographic techniques and further identified through 1D NMR spectroscopic and mass spectrometry analysis. Hispidin and hypholomine B were found to inhibit the infection of SARS-CoV-2 pseudovirus by reducing angiotensin-converting enzyme 2 gene expression in HepG2, thereby decreasing viral entry. Moreover, hispidin and hypholomine B effectively block the spike receptor-binding domain, while hypholomine B, for the first time, showed significant inhibition of 3CL protease. This suggests that GKPL, enriched with hispidin and hypholomine B, has the potential to be used as an active ingredient against SARS-CoV-2.PMID:37797793 | DOI:10.1016/j.fitote.2023.105695

Life Sci. 2023 Oct 3:122142. doi: 10.1016/j.lfs.2023.122142. Online ahead of print.ABSTRACTAIMS: In this study, highland barley (HB), HB bran (HBB) and whole grain HB (WGHB) alleviating hyperlipemia and liver inflammation in high fat and cholesterol diet (HFCD) mice was investigated.METHODS: All 50 ICR mice were randomly allocated to 5 treatment groups: Normal control group, HFCD group, HB group, HBB group and WGHB group. The serum lipid profiles, liver and epididymal adipocyte histology, gut microbiota and untargeted metabolomics were adopted.KEY FINDINGS: The results suggested that HB especially HBB supplement could obviously decrease BW and BWG. Serum lipid profiles showed that HB especially HBB decreased TG, TC, LDL-C, ALT and AST levels while increased HDL-C level. Liver and epididymal adipocyte H&E staining also confirmed that hepatic injury and adipose accumulation were alleviated by HB especially HBB. Gut microbiota analysis indicated that HBB increased Bacteroidetes/Firmicutes ratio, Lactobacillus and Akkermansia muciniphila abundances while decreased Proteobacteria and Shigella abundances. Untargeted metabolomics results showed that HBB significantly increased deoxycholic acid levels compared with HFCD mice and HBB regulated arachidonic acid metabolism pathway.SIGNIFICANCE: The obtained results provided important information about the processing of highland barley to retain its hypolipidemic effect and improve its acceptability and biosafety, and had a guiding effect on the development of HB products.PMID:37797689 | DOI:10.1016/j.lfs.2023.122142

Cell Metab. 2023 Sep 29:S1550-4131(23)00340-6. doi: 10.1016/j.cmet.2023.09.009. Online ahead of print.ABSTRACTEmerging studies have addressed the tumor-promoting role of fructose in different cancers. The effects and pathological mechanisms of high dietary fructose on hepatocellular carcinoma (HCC) remain unclear. Here, we examined the effects of fructose supplementation on HCC progression in wild-type C57BL/6 mice using a spontaneous and chemically induced HCC mouse model. We show that elevated uridine diphospho-N-acetylglucosamine (UDP-GlcNAc) and O-GlcNAcylation levels induced by high dietary fructose contribute to HCC progression. Non-targeted metabolomics and stable isotope tracing revealed that under fructose treatment, microbiota-derived acetate upregulates glutamine and UDP-GlcNAc levels and enhances protein O-GlcNAcylation in HCC. Global profiling of O-GlcNAcylation revealed that hyper-O-GlcNAcylation of eukaryotic elongation factor 1A1 promotes cell proliferation and tumor growth. Targeting glutamate-ammonia ligase or O-linked N-acetylglucosamine transferase (OGT) remarkably impeded HCC progression in mice with high fructose intake. We propose that high dietary fructose promotes HCC progression through microbial acetate-induced hyper-O-GlcNAcylation.PMID:37797623 | DOI:10.1016/j.cmet.2023.09.009

Neurobiol Aging. 2023 Aug 29;132:109-119. doi: 10.1016/j.neurobiolaging.2023.08.009. Online ahead of print.ABSTRACTThe prefrontal cortex (PFC) has been implicated as a key brain region responsible for age-related cognitive decline. Little is known about aging-related molecular changes in PFC that may mediate these effects. To date, no studies have used untargeted discovery methods with integrated analyses to determine PFC molecular changes in healthy female primates. We quantified PFC changes associated with healthy aging in female baboons by integrating multiple omics data types (transcriptomics, proteomics, metabolomics) from samples across the adult age span. Our integrated omics approach using unbiased weighted gene co-expression network analysis to integrate data and treat age as a continuous variable, revealed highly interconnected known and novel pathways associated with PFC aging. We found Gamma-aminobutyric acid (GABA) tissue content associated with these signaling pathways, providing 1 potential biomarker to assess PFC changes with age. These highly coordinated pathway changes during aging may represent early steps for aging-related decline in PFC functions, such as learning and memory, and provide potential biomarkers to assess cognitive status in humans.PMID:37797463 | DOI:10.1016/j.neurobiolaging.2023.08.009

Clin Epigenetics. 2023 Oct 5;15(1):158. doi: 10.1186/s13148-023-01567-w.ABSTRACTBACKGROUND: MTR gene encodes the cytoplasmic enzyme methionine synthase, which plays a pivotal role in the methionine cycle of one-carbon metabolism. This cycle holds a significant importance in generating S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH), the respective universal methyl donor and end-product of epigenetic transmethylation reactions. cblG type of inherited disorders of vitamin B12 metabolism due to mutations in MTR gene exhibits a wide spectrum of symptoms, including a retinopathy unresponsive to conventional therapies.METHODS: To unveil the underlying epigenetic pathological mechanisms, we conducted a comprehensive study of epigenomic-wide alterations of DNA methylation by NGS of bisulfited retinal DNA in an original murine model with conditional Mtr deletion in retinal tissue. Our focus was on postnatal day 21, a critical developmental juncture for ocular structure refinement and functional maturation.RESULTS: We observed delayed eye opening and impaired visual acuity and alterations in the one-carbon metabolomic profile, with a notable dramatic decline in SAM/SAH ratio predicted to impair DNA methylation. This metabolic disruption led to epigenome-wide changes in genes involved in eye development, synaptic plasticity, and retinoid metabolism, including promoter hypermethylation of Rarα, a regulator of Lrat expression. Consistently, we observed a decline in cone photoreceptor cells and reduced expression of Lrat, Rpe65, and Rdh5, three pivotal genes of eye retinoid metabolism.CONCLUSION: We introduced an original in vivo model for studying cblG retinopathy, which highlighted the pivotal role of altered DNA methylation in eye development, cone differentiation, and retinoid metabolism. This model can be used for preclinical studies of novel therapeutic targets.PMID:37798757 | DOI:10.1186/s13148-023-01567-w

Arch Toxicol. 2023 Oct 6. doi: 10.1007/s00204-023-03612-2. Online ahead of print.ABSTRACTNanoparticles have been used in neurological research in recent years because of their blood-brain barrier penetration activity. However, their potential neuronanotoxicity remains a concern. In particular, microglia, which are resident phagocytic cells, are mainly exposed to nanoparticles in the brain. We investigated the changes in lysosomal function in silica-coated magnetic nanoparticles containing rhodamine B isothiocyanate dye [MNPs@SiO2(RITC)]-treated BV2 murine microglial cells. In addition, we analyzed amyloid beta (Aβ) accumulation and molecular changes through the integration of transcriptomics, proteomics, and metabolomics (triple-omics) analyses. Aβ accumulation significantly increased in the 0.1 μg/μl MNPs@SiO2(RITC)-treated BV2 cells compared to the untreated control and 0.01 μg/μl MNPs@SiO2(RITC)-treated BV2 cells. Moreover, the MNPs@SiO2(RITC)-treated BV2 cells showed lysosomal swelling, a dose-dependent reduction in proteolytic activity, and an increase in lysosomal swelling- and autophagy-related protein levels. Moreover, proteasome activity decreased in the MNPs@SiO2(RITC)-treated BV2 cells, followed by a concomitant reduction in intracellular adenosine triphosphate (ATP). By employing triple-omics and a machine learning algorithm, we generated an integrated single molecular network including reactive oxygen species (ROS), autophagy, lysosomal storage disease, and amyloidosis. In silico analysis of the single triple omics network predicted an increase in ROS, suppression of autophagy, and aggravation of lysosomal storage disease and amyloidosis in the MNPs@SiO2(RITC)-treated BV2 cells. Aβ accumulation and lysosomal swelling in the cells were alleviated by co-treatment with glutathione (GSH) and citrate. These findings suggest that MNPs@SiO2(RITC)-induced reduction in lysosomal activity and proteasomes can be recovered by GSH and citrate treatment. These results also highlight the relationship between nanotoxicity and Aβ accumulation.PMID:37798515 | DOI:10.1007/s00204-023-03612-2

J Biosci Bioeng. 2023 Oct 3:S1389-1723(23)00301-8. doi: 10.1016/j.jbiosc.2023.09.006. Online ahead of print.ABSTRACTIn current research, yeast species Issatchenkia terricola WJL-G4 was shown to be capable of degrading citric acid, especially in the processing of fruit juice and wine. I. terricola WJL-G4 was able to use citric acid as a carbon source, but the metabolic effects of citric acid on yeast remained unclear. In this study, the metabolic effects of citric acid on I. terricola WJL-G4 were studied using liquid chromatography-mass spectrometry metabolomics technology, with glucose treatment as the control. Results showed that organic acid contents related to the extracellular tricarboxylic acid cycle (TCA) varied greatly. The metabolomics results indicated that I. terricola WJL-G4 might metabolize citric acid through the TCA pathway, and the glycolysis pathway might be inhibited; however, gluconeogenesis proceeded normally during citric acid treatment. Some fatty acids and phospholipids, along with the metabolic pathways of amino acids, vitamins, purines and nicotinamide in I. terricola WJL-G4 were also affected by the citric acid treatment. This work provided a theoretical basis for further study of the mechanism of yeast metabolism of citric acid.PMID:37798226 | DOI:10.1016/j.jbiosc.2023.09.006

Redox Biol. 2023 Sep 26;67:102907. doi: 10.1016/j.redox.2023.102907. Online ahead of print.ABSTRACTCardiac fibrosis is characterized by the excessive deposition of extracellular matrix in the myocardium with cardiac fibroblast activation, leading to chronic cardiac remodeling and dysfunction. However, little is known about metabolic alterations in fibroblasts during cardiac fibrosis, and there is a lack of pharmaceutical treatments that target metabolic dysregulation. Here, we provided evidence that fatty acid β-oxidation (FAO) dysregulation contributes to fibroblast activation and cardiac fibrosis. With transcriptome, metabolome, and functional assays, we demonstrated that FAO was downregulated during fibroblast activation and cardiac fibrosis, and that perturbation of FAO reversely affected the fibroblast-to-myofibroblast transition. The decrease in FAO may be attributed to reduced long-chain fatty acid (LCFA) uptake. Voltage-dependent anion channel 1 (VDAC1), the main gatekeeper of the outer mitochondrial membrane (OMM), serves as the transporter of LCFA into the mitochondria for further utilization and has been shown to be decreased in myofibroblasts. In vitro, the addition of exogenous VDAC1 was shown to ameliorate cardiac fibroblast activation initiated by transforming growth factor beta 1 (TGF-β1) stimuli, and silencing of VDAC1 displayed the opposite effect. A mechanistic study revealed that VDAC1 exerts a protective effect by regulating LCFA uptake into the mitochondria, which is impaired by an inhibitor of carnitine palmitoyltransferase 1A. In vivo, AAV9-mediated overexpression of VDAC1 in myofibroblasts significantly alleviated transverse aortic constriction (TAC)-induced cardiac fibrosis and rescued cardiac function in mice. Finally, we treated mice with the VDAC1-derived R-Tf-D-LP4 peptide, and the results showed that R-Tf-D-LP4 prevented TAC-induced cardiac fibrosis and dysfunction in mice. In conclusion, this study provides evidence that VDAC1 maintains FAO metabolism in cardiac fibroblasts to repress fibroblast activation and cardiac fibrosis and suggests that the VDAC1 peptide is a promising drug for rescuing fibroblast metabolism and repressing cardiac fibrosis.PMID:37797372 | DOI:10.1016/j.redox.2023.102907

Environ Sci Technol. 2023 Oct 5. doi: 10.1021/acs.est.3c04845. Online ahead of print.ABSTRACTAdverse effects associated with chemical exposures during pregnancy include several developmental and reproductive disorders. However, considering the tens of thousands of chemicals present on the market, the effects of chemical mixtures on the developing fetus is still likely underestimated. In this critical review, we discuss the potential to apply innovative biomonitoring methods using high-resolution mass spectrometry (HRMS) on placenta to improve the monitoring of chemical exposure during pregnancy. The physiology of the placenta and its relevance as a matrix for monitoring chemical exposures and their effects on fetal health is first outlined. We then identify several key parameters that require further investigations before placenta can be used for large-scale monitoring in a robust manner. Most critical is the need for standardization of placental sampling. Placenta is a highly heterogeneous organ, and knowledge of the intraplacenta variability of chemical composition is required to ensure unbiased and robust interindividual comparisons. Other important variables include the time of collection, the sex of the fetus, and mode of delivery. Finally, we discuss the first applications of HRMS methods on the placenta to decipher the chemical exposome and describe how the use of placenta can complement biofluids collected on the mother or the fetus.PMID:37796725 | DOI:10.1021/acs.est.3c04845