PubMed
Dopaminergic and serotoninergic neurotoxicity of lanthanide phosphate (TbPO<sub>4</sub>) in developing zebrafish
Chemosphere. 2023 Aug 17:139861. doi: 10.1016/j.chemosphere.2023.139861. Online ahead of print.ABSTRACTRare earth elements (REEs) are exploited for global use in manufacturing. Such activities result in their release into the environment and the transformation into more stable phosphate deposition. The objective of this study was to evaluate molecular and behavioral changes of zebrafish exposed to the synthesized terbium phosphate (TbPO4) at concentrations of 10, 20, and 50 mg/L and to determine its potential for neurotoxicity. Metabolomics related to neurotransmitters, and assessment of transcripts and proteins were conducted to uncover the molecular mechanisms underlying TbPO4 with emphasis on neurotransmitter systems. Exposure to 20 mg/L TbPO4 induced larval hyperactivity and perturbed the cholinergic system in zebrafish. Based on metabolomics related to neurotransmitters, dopamine (DA), serotonin (5-HT), and many of their precursors and metabolites were decreased in abundance by TbPO4. In addition, the expression levels of transcripts related to the synthesis, transport, receptor binding, and metabolism of DA and 5-HT were analyzed at the mRNA and protein levels. Transcript and protein levels for tyrosine hydroxylase (TH), the rate-limiting enzyme for DA synthesis, were down-regulated in larval fish. Monoamine oxidase (MAO), an enzyme that catabolizes monoamines DA and 5-HT, also reduced mRNA abundance. We hypothesize that DA synthesis and monoamine metabolism are associated with behavioral alterations. In addition, a mechanism for the disruption of neurotransmitter systems by TbPO4 may be the apoptosis of neurons. This study elucidates putative mechanisms and exposure risks to wildlife and humans by characterizing phosphatic REE-induced neurotoxicity in developing zebrafish.PMID:37597622 | DOI:10.1016/j.chemosphere.2023.139861
Metabolic classification suggests the GLUT1/ALDOB/G6PD axis as a therapeutic target in chemotherapy-resistant pancreatic cancer
Cell Rep Med. 2023 Aug 10:101162. doi: 10.1016/j.xcrm.2023.101162. Online ahead of print.ABSTRACTMetabolic reprogramming is known as an emerging mechanism of chemotherapy resistance, but the metabolic signatures of pancreatic ductal adenocarcinomas (PDACs) remain unclear. Here, we characterize the metabolomic profile of PDAC organoids and classify them into glucomet-PDAC (high glucose metabolism levels) and lipomet-PDAC (high lipid metabolism levels). Glucomet-PDACs are more resistant to chemotherapy than lipomet-PDACs, and patients with glucomet-PDAC have a worse prognosis. Integrated analyses reveal that the GLUT1/aldolase B (ALDOB)/glucose-6-phosphate dehydrogenase (G6PD) axis induces chemotherapy resistance by remodeling glucose metabolism in glucomet-PDAC. Increased glycolytic flux, G6PD activity, and pyrimidine biosynthesis are identified in glucomet-PDAC with high GLUT1 and low ALDOB expression, and these phenotypes could be reversed by inhibiting GLUT1 expression or by increasing ALDOB expression. Pharmacological inhibition of GLUT1 or G6PD enhances the chemotherapy response of glucomet-PDAC. Our findings uncover potential metabolic heterogeneity related to differences in chemotherapy sensitivity in PDAC and develop a promising pharmacological strategy for patients with chemotherapy-resistant glucomet-PDAC through the combination of chemotherapy and GLUT1/ALDOB/G6PD axis inhibitors.PMID:37597521 | DOI:10.1016/j.xcrm.2023.101162
Metabolic characterisation of transglutaminase 2 inhibitor effects in breast cancer cell lines
FEBS J. 2023 Aug 19. doi: 10.1111/febs.16931. Online ahead of print.ABSTRACTTransglutaminase 2 (TG2), mediating post-translational modifications of multiple intracellular enzymes, is involved in the pathogenesis and progression of cancer. We used 1 H-NMR metabolomics to study the effects of AA9, a novel TG2 inhibitor, on two breast cancer cell lines with distinct phenotypes, MCF-7 and MDA-MB-231. AA9 can promote apoptosis in both cell lines, but it is particularly effective in MD-MB-231, inhibiting transamidation reactions and decreasing cell migration and invasiveness. This metabolomics study provides evidence of a major effect of AA9 on MDA-MB-231 cells, impacting glutamate and aspartate metabolism, rather than on MCF-7 cells, characterized by choline and O-phosphocholine decrease. Interestingly, AA9 treatment induces myo-inositol alteration in both cell lines, indicating action on phosphatidylinositol metabolism, likely modulated by the G-protein activity of TG2 on phospholipase C. Considering the metabolic deregulations that characterize various breast cancer subtypes, the existence of a metabolic pathway affected by AA9 further points to TG2 as a promising hot spot. The metabolomics approach provides a powerful tool to monitor the effectiveness of inhibitors and to better understand the role of TG2 in cancer.PMID:37597264 | DOI:10.1111/febs.16931
Reduced iron and cobalt levels in response to curcumin supplementation are not responsible for the prolonged larval development and do not affect the oxidative stress tolerance and polyamine status of D. melanogaster
Biofactors. 2023 Aug 19. doi: 10.1002/biof.2000. Online ahead of print.ABSTRACTRecent reports indicated that the phytochemical curcumin possesses iron-chelating activity. Here, by employing the fruit fly Drosophila melanogaster, we conducted feeding studies supplementing curcumin or, as a control, the iron chelator bathophenanthroline (BPA). First, the absorption and further metabolization of dietary curcuminoids were proved by metabolomics analyses. Next, we found that 0.2% dietary curcumin, similar to BPA, lowered the iron but also the cobalt content, and to a lesser extent affected the manganese and zinc status. Supplementation during larval stages was required and sufficient for both compounds to elicit these alterations in adult animals. However, curcumin-induced retarded larval development was not attributable to the changed trace metal status. In addition, a reduction in the iron content of up to 70% by curcumin or BPA supplementation did not reduce heme-dependent catalase activity and tolerance toward H2 O2 in D. melanogaster. Moreover, polyamines were not influenced by curcumin treatment and decreased iron levels. This was confirmed for selected organs from 0.2% curcumin-treated mice, except for the spleen. Here, elevated spermidine level and concomitant upregulation of genes involved in polyamine production were associated with a putatively anemia-derived increased spleen mass. Our data underline that the metal-chelating property of curcumin needs to be considered in feeding studies.PMID:37597249 | DOI:10.1002/biof.2000
Multiplexed targeted analysis of polyunsaturated fatty acids and oxylipins using liquid chromatography-tandem mass spectrometry
STAR Protoc. 2023 Aug 17;4(3):102226. doi: 10.1016/j.xpro.2023.102226. Online ahead of print.ABSTRACTPolyunsaturated fatty acids (PUFAs) and their oxidized products (oxylipins) are important mediators in intra- and extra-cellular signaling. We describe here the simultaneous quantification of 163 PUFAs and oxylipins using liquid chromatography-mass spectrometry (LC-MS). The protocol details steps for PUFA purification from various biological materials, the conditions for LC-MS analysis, as well as quantitative approaches for data evaluation. We provide an example of PUFA quantification in animal tissue along with the bioinformatic protocol, enabling efficient inter-sample comparison and statistical analysis. For complete details on the use and execution of this protocol, please refer to Vila et al.,1 Costanza et al.,2 Blomme et al.,3 and Blomme et al.4.PMID:37597187 | DOI:10.1016/j.xpro.2023.102226
Metabolomics targets tissue-specific responses in alleviating the negative effects of salinity in tef (Eragrostis tef) during germination
Planta. 2023 Aug 19;258(3):67. doi: 10.1007/s00425-023-04224-x.ABSTRACTSalinity induced metabolite responses resulted in differential accumulation of flavonoids and antioxidant metabolites in shoots and roots suggesting improved antioxidant capacity in providing salt-adaptive phenotype of tef seedling. Tef [(Eragrostis tef) (Zucc.) Trotter] is an important 'cash crop' of Ethiopia grown mainly for human food, and development of elite tef cultivars with better performance is vital to Ethiopian farmers and breeders. Soil salinity is one of the key constraints that affects tef yield in the Ethiopian lowlands and Rift valley where cultivation of tef is limited. Being a minor crop, the responses of tef towards salinity is unknown. Salinity involves physiological and metabolite reprogramming that can have major impact on germination and seedling establishment. Here we evaluate the in vitro effect of NaCl on tef germination and associate this with metabolomic approaches to suggest salt tolerance mechanisms. In this study, 19 tef varieties were screened for NaCl tolerance and were investigated using untargeted metabolomics. Screened tef varieties showed differential germination rates with NaCl treatment varying from < 20 to 100%. Viable seedlings exposed to NaCl exhibited purple-red pigment accumulation in the roots except for Beten and Tullu nasy varieties. Metabolite comparisons between shoots and roots showed significant differences and, in particular, roots of salt tolerant tef varieties accumulated flavonoid derivatives as well as sugars and cell wall associated metabolites. These metabolic changes were correlated with patterns of antioxidant capacities and total flavonoid content in shoots and roots and suggested a mitigating response by tef to salinity. Our study highlights the role of flavonoid accumulation following salt stress on tef seedlings and further these findings could be used as targets for selective tef breeding.PMID:37597049 | DOI:10.1007/s00425-023-04224-x
Immunogenic cell death (ICD) enhancers-Drugs that enhance the perception of ICD by dendritic cells
Immunol Rev. 2023 Aug 19. doi: 10.1111/imr.13269. Online ahead of print.ABSTRACTThe search for immunostimulatory drugs applicable to cancer immunotherapy may profit from target-agnostic methods in which agents are screened for their functional impact on immune cells cultured in vitro without any preconceived idea on their mode of action. We have built a synthetic mini-immune system in which stressed and dying cancer cells (derived from standardized cell lines) are confronted with dendritic cells (DCs, derived from immortalized precursors) and CD8+ T-cell hybridoma cells expressing a defined T-cell receptor. Using this system, we can identify three types of immunostimulatory drugs: (i) pharmacological agents that stimulate immunogenic cell death (ICD) of malignant cells; (ii) drugs that act on DCs to enhance their response to ICD; and (iii) drugs that act on T cells to increase their effector function. Here, we focus on strategies to develop drugs that enhance the perception of ICD by DCs and to which we refer as "ICD enhancers." We discuss examples of ICD enhancers, including ligands of pattern recognition receptors (exemplified by TLR3 ligands that correct the deficient function of DCs lacking FPR1) and immunometabolic modifiers (exemplified by hexokinase-2 inhibitors), as well as methods for target deconvolution applicable to the mechanistic characterization of ICD enhancers.PMID:37596984 | DOI:10.1111/imr.13269
Long-term rain exclusion in a Mediterranean forest: response of physiological and physico-chemical traits of Quercus pubescens across seasons
Plant J. 2023 Aug 19. doi: 10.1111/tpj.16424. Online ahead of print.ABSTRACTWith climate change, an aggravation in summer drought is expected in the Mediterranean region. To assess the impact of such a future scenario, we compared the response of Quercus pubescens, a drought-resistant deciduous oak species, to long-term amplified drought (AD) (partial rain exclusion in natura for 10 years) and natural drought (ND). We studied leaf physiological and physico-chemical trait responses to ND and AD over the seasonal cycle, with a focus on chemical traits including major groups of central (photosynthetic pigments and plastoquinones) and specialized (tocochromanols, phenolic compounds, and cuticular waxes) metabolites. Seasonality was the main driver of all leaf traits, including cuticular triterpenoids, which were highly concentrated in summer, suggesting their importance to cope with drought and thermal stress periods. Under AD, trees not only reduced CO2 assimilation (-42%) in summer and leaf concentrations of some phenolic compounds and photosynthetic pigments (carotenoids from the xanthophyll cycle) but also enhanced the levels of other photosynthetic pigments (chlorophylls, lutein, and neoxanthin) and plastochromanol-8, an antioxidant located in chloroplasts. Overall, the metabolomic adjustments across seasons and drought conditions reinforce the idea that Q. pubescens is highly resistant to drought although significant losses of antioxidant defenses and photoprotection were identified under AD.PMID:37596909 | DOI:10.1111/tpj.16424
Increased serum α-tocopherol acetate mediated by gut microbiota ameliorates alveolar bone loss through the STAT3 signalling pathway in diabetic periodontitis
J Clin Periodontol. 2023 Aug 19. doi: 10.1111/jcpe.13862. Online ahead of print.ABSTRACTAIM: To evaluate whether and how gut microbiota-meditated metabolites regulate alveolar bone homeostasis in diabetic periodontitis (DP).MATERIALS AND METHODS: Lactobacillus casei (L. casei) was employed as a positive modulator of gut microbiota in DP mice. The destruction of alveolar bone was evaluated. Untargeted metabolomics was conducted to screen out the pivotal metabolites. A co-housing experiment was conducted to determine the connection between the gut microbiota and alpha-tocopherol acetate (α-TA). α-TA was applied to DP mice to investigate its effect against alveolar bone loss. Human periodontal ligament cells (hPDLCs) and human gingival fibroblasts (HGFs) were extracted for the in vitro experiment. Transcriptomic analysis and immunohistochemistry were performed to detect the major affected signalling pathways.RESULTS: Positive regulation of the gut microbiota significantly attenuated alveolar bone loss and increased the serum α-TA level. The alteration in gut microbiota composition could affect the serum α-T (the hydrolysates of α-TA) level. α-TA could alleviate alveolar bone destruction in DP mice and α-T exert beneficial effects on hPDLCs and HGFs. Mechanistically, the STAT3 signalling pathway was the pivotal pathway involved in the protective role of α-TA.CONCLUSIONS: The gut microbiota-α-TA-STAT3 axis plays an important role in the regulation of diabetic alveolar bone homeostasis.PMID:37596824 | DOI:10.1111/jcpe.13862
HIV infection in adult Ugandans with new-onset type 2 diabetes: exploring its influence on the anthropometric and metabolic profile
AIDS Res Ther. 2023 Aug 18;20(1):56. doi: 10.1186/s12981-023-00553-9.ABSTRACTOBJECTIVE: HIV infection increases the risk of type 2 diabetes and may influence its phenotypic profile. In this study, we aimed to compare the anthropometric and metabolic characteristics of HIV-infected and uninfected adult Ugandans with new-onset type 2 diabetes to evaluate the influence of HIV infection on specific surrogate markers of adiposity, insulin resistance, and pancreatic beta-cell function.METHODS: We consecutively recruited 500 HIV-infected and uninfected adult Ugandans with new-onset type 2 diabetes (diagnosed in < 3 months) from seven tertiary hospitals over a 20-month period and compared their anthropometric and metabolic characteristics to identify any significant differences.RESULTS: Of the 500 participants with new-onset type 2 diabetes, 59 (11.8%) had a self-reported history of HIV infection. Compared with HIV-uninfected participants with type 2 diabetes, participants with HIV infection and type 2 diabetes had a lower median (IQR) hip circumference (97.8 [91.0-106.0] cm vs. 104.0 [96.0-112.0], p = 0.002) and visceral fat level (8 [6-11] vs. 10 [7-12], p < 0.001) assessed using bioimpedance analysis. No statistically significant difference was noted with the markers of pancreatic beta-cell function (fasting, 30-minute, and 120-minute C-peptide concentrations, oral insulinogenic index, and homeostatic model assessment 2-beta cell function) and insulin resistance (homeostatic model assessment 2-insulin resistance) between both groups.CONCLUSION: In our study population, HIV infection was not associated with increased adiposity, pancreatic beta-cell function, and insulin resistance. Large prospective studies are needed to investigate the effect of HIV on the pathogenesis of type 2 diabetes in adult Ugandans.PMID:37596620 | PMC:PMC10439581 | DOI:10.1186/s12981-023-00553-9
Influenza A virus infection disrupts oligodendrocyte homeostasis and alters the myelin lipidome in the adult mouse
J Neuroinflammation. 2023 Aug 19;20(1):190. doi: 10.1186/s12974-023-02862-2.ABSTRACTBACKGROUND: Recent data suggest that myelin may be altered by physiological events occurring outside of the central nervous system, which may cause changes to cognition and behavior. Similarly, peripheral infection by non-neurotropic viruses is also known to evoke changes to cognition and behavior.METHODS: Mice were inoculated with saline or influenza A virus. Bulk RNA-seq, lipidomics, RT-qPCR, flow cytometry, immunostaining, and western blots were used to determine the effect of infection on OL viability, protein expression and changes to the lipidome. To determine if microglia mediated infection-induced changes to OL homeostasis, mice were treated with GW2580, an inhibitor of microglia activation. Additionally, conditioned medium experiments using primary glial cell cultures were also used to test whether secreted factors from microglia could suppress OL gene expression.RESULTS: Transcriptomic and RT-qPCR analyses revealed temporal downregulation of OL-specific transcripts with concurrent upregulation of markers characteristic of cellular stress. OLs isolated from infected mice had reduced cellular expression of myelin proteins compared with those from saline-inoculated controls. In contrast, the expression of these proteins within myelin was not different between groups. Similarly, histological and immunoblotting analysis performed on various brain regions indicated that infection did not alter OL viability, but increased expression of a cellular stress marker. Shot-gun lipidomic analysis revealed that infection altered the lipid profile within the prefrontal cortex as well as in purified brain myelin and that these changes persisted after recovery from infection. Treatment with GW2580 during infection suppressed the expression of genes associated with glial activation and partially restored OL-specific transcripts to baseline levels. Finally, conditioned medium from activated microglia reduced OL-gene expression in primary OLs without altering their viability.CONCLUSIONS: These findings show that peripheral respiratory viral infection with IAV is capable of altering OL homeostasis and indicate that microglia activation is likely involved in the process.PMID:37596606 | PMC:PMC10439573 | DOI:10.1186/s12974-023-02862-2
Seasonal patterns in microbial carbon and iron transporter expression in the Southern Ocean
Microbiome. 2023 Aug 19;11(1):187. doi: 10.1186/s40168-023-01600-3.ABSTRACTBACKGROUND: Heterotrophic microbes in the Southern Ocean are challenged by the double constraint of low concentrations of organic carbon (C) and iron (Fe). These essential elements are tightly coupled in cellular processes; however, the prokaryotic requirements of C and Fe under varying environmental settings remain poorly studied. Here, we used a combination of metatranscriptomics and metaproteomics to identify prokaryotic membrane transporters for organic substrates and Fe in naturally iron-fertilized and high-nutrient, low-chlorophyll waters of the Southern Ocean during spring and late summer.RESULTS: Pronounced differences in membrane transporter profiles between seasons were observed at both sites, both at the transcript and protein level. When specific compound classes were considered, the two approaches revealed different patterns. At the transcript level, seasonal patterns were only observed for subsets of genes belonging to each transporter category. At the protein level, membrane transporters of organic compounds were relatively more abundant in spring as compared to summer, while the opposite pattern was observed for Fe transporters. These observations suggest an enhanced requirement for organic C in early spring and for Fe in late summer. Mapping transcripts and proteins to 50 metagenomic-assembled genomes revealed distinct taxon-specific seasonal differences pointing to potentially opportunistic clades, such as Pseudomonadales and Nitrincolaceae, and groups with a more restricted repertoire of expressed transporters, such as Alphaproteobacteria and Flavobacteriaceae.CONCLUSION: The combined investigations of C and Fe membrane transporters suggest seasonal changes in the microbial requirements of these elements under different productivity regimes. The taxon-specific acquisition strategies of different forms of C and Fe illustrate how diverse microbes could shape transcript and protein expression profiles at the community level at different seasons. Our results on the C- and Fe-related metabolic capabilities of microbial taxa provide new insights into their potential role in the cycling of C and Fe under varying nutrient regimes in the Southern Ocean. Video Abstract.PMID:37596690 | DOI:10.1186/s40168-023-01600-3
BLINK enables ultrafast tandem mass spectrometry cosine similarity scoring
Sci Rep. 2023 Aug 18;13(1):13462. doi: 10.1038/s41598-023-40496-9.ABSTRACTMetabolomics has a long history of using cosine similarity to match experimental tandem mass spectra to databases for compound identification. Here we introduce the Blur-and-Link (BLINK) approach for scoring cosine similarity. By bypassing fragment alignment and simultaneously scoring all pairs of spectra using sparse matrix operations, BLINK is over 3000 times faster than MatchMS, a widely used loop-based alignment and scoring implementation. Using a similarity cutoff of 0.7, BLINK and MatchMS had practically equivalent identification agreement, and greater than 99% of their scores and matching ion counts were identical. This performance improvement can enable calculations to be performed that would typically be limited by time and available computational resources.PMID:37596301 | DOI:10.1038/s41598-023-40496-9
One-carbon metabolizing enzyme ALDH1L1 influences mitochondrial metabolism through 5-aminoimidazole-4-carboxamide ribonucleotide accumulation and serine depletion, contributing to tumor suppression
Sci Rep. 2023 Aug 18;13(1):13486. doi: 10.1038/s41598-023-38142-5.ABSTRACTTumor cells generally require large amounts of nucleotides, and thus activate de novo purine synthesis (dnPS). In the dnPS reactions, 10-formyltetrahydorofolate (10-fTHF) supplied by one-carbon metabolism is utilized as a formyl group donor. We focused on aldehyde dehydrogenase 1 family member L1 (ALDH1L1), which metabolizes 10-fTHF to tetrahydrofolate and whose expression is often attenuated in hepatocellular carcinoma (HCC). We generated ALDH1L1-expressing HuH-7 cells to perform metabolome analysis and found that intracellular levels of serine were reduced and glycine was increased. In addition, 5-aminoimidazole-4-carboxamide ribonucleotide (ZMP), a dnPS intermediate, accumulated due to the consumption of 10-fTHF by ALDH1L1, which inhibited ZMP formylation. Importantly, ALDH1L1-expressing cells showed reduced ZMP sensitivity and higher mitochondrial activity. The suppression of mitochondrial serine catabolism by ALDH1L1 expression was speculated to be closely related to this phenotype. Gene set enrichment analysis utilizing The Cancer Genome Atlas data revealed that genes related to oxidative phosphorylation were enriched in HCC patients with high ALDH1L1 expression. Moreover, drug sensitivity data analysis demonstrated that HCC cell lines with low expression of ALDH1L1 were sensitive to ZMP and cordycepin, a structural analog of ZMP and AMP. Our study revealed that ZMP and AMP analogs might be effective in the pharmacotherapy of HCC patients with low expression of ALDH1L1.PMID:37596270 | DOI:10.1038/s41598-023-38142-5
Temporal modelling of the biofilm lifecycle (TMBL) establishes kinetic analysis of plate-based bacterial biofilm dynamics
J Microbiol Methods. 2023 Aug 16:106808. doi: 10.1016/j.mimet.2023.106808. Online ahead of print.ABSTRACTBacterial biofilms are critical to pathogenesis and infection. They are associated with rising rates of antimicrobial resistance. Biofilms are correlated with worse clinical outcomes, making them important to infectious diseases research. There is a gap in knowledge surrounding biofilm kinetics and dynamics which makes biofilm research difficult to translate from bench to bedside. To address this gap, this work employs a well-characterized crystal violet biomass accrual and planktonic cell density assay across a clinically relevant time course and expands statistical analysis to include kinetic information in a protocol termed the TMBL (Temporal Mapping of the Biofilm Lifecycle) assay. TMBL's statistical framework quantitatively compares biofilm communities across time, species, and media conditions in a 96-well format. Measurements from TMBL can reliably be condensed into response features that inform the time-dependent behavior of adherent biomass and planktonic cell populations. Staphylococcus aureus and Pseudomonas aeruginosa biofilms were grown in conditions of metal starvation in nutrient-variable media to demonstrate the rigor and translational potential of this strategy. Significant differences in single-species biofilm formation are seen in metal-deplete conditions as compared to their controls which is consistent with the consensus literature on nutritional immunity that metal availability drives transcriptomic and metabolomic changes in numerous pathogens. Taken together, these results suggest that kinetic analysis of biofilm by TMBL represents a statistically and biologically rigorous approach to studying the biofilm lifecycle as a time-dependent process. In addition to current methods to study the impact of microbe and environmental factors on the biofilm lifecycle, this kinetic assay can inform biological discovery in biofilm formation and maintenance.PMID:37595876 | DOI:10.1016/j.mimet.2023.106808
Combination of sulfide-driven partial denitrification with anammox enhanced by zeolite powder for autotrophic nitrogen and sulfide removal from wastewater
Environ Res. 2023 Aug 16:116906. doi: 10.1016/j.envres.2023.116906. Online ahead of print.ABSTRACTSulfide-driven partial denitrification and anaerobic ammonia oxidizing (anammox) (SPDA) is a high-efficiency technology to achieve simultaneous nitrogen and sulfide removal. Nitrite accumulation from sulfide-driven partial denitrification is the key to achieve SPDA. Zeolite powder was added to strengthen the competition of anammox bacteria against nitrite. The nitrogen removal rate (NRR) and partial denitrification efficiency in reactor was 5.18 kg-N m-3d-1 and 92.3% during 180 days of operation, higher than those without zeolite powder, indicating an improving contribution of zeolite powder. Metabolomics analysis revealed zeolite powder addition enhanced the metabolisms of amino acids, nicotinate and porphyrin through increasing glutamate content, and improved EPS secretion, heme c content and particle size. Besides, high ammonia enriched by zeolite powder was conducive to improve anammox activity and NRR. This study provides the metabolic insights into the mechanism of zeolite powder enhancing SPDA, which is meaningful towards overcoming the limitations in practical application of SDPA.PMID:37595825 | DOI:10.1016/j.envres.2023.116906
Combination of Coptis chinensis polysaccharides and berberine ameliorates ulcerative colitis by regulating gut microbiota and activating AhR/IL-22 pathway
J Ethnopharmacol. 2023 Aug 16:117050. doi: 10.1016/j.jep.2023.117050. Online ahead of print.ABSTRACTETHNOPHARMACOLOGICAL RELEVANCE: Coptis chinensis Franch. polysaccharide (CCP) and berberine (BBR) are the primary active components of Coptis chinensis Franch. BBR is clinically used for the treatment of intestinal infections and gastroenteritis. CCP was also reported to be effective for the treatment of ulcerative colitis (UC). However, whether CCP combined with BBR shows a synergistic effect on the treatment of UC has not been elucidated yet.AIM OF THE STUDY: This study aspired to investigate the therapeutic effect and the possible mechanisms of the combination of CCP with BBR on chronic UC.MATERIALS AND METHODS: By periodic administration of dextran sulfate sodium (DSS) to C57BL/6J mice, chronic UC model mice were induced. CCP (15 mg/kg), BBR (50 mg/kg), and CCP.BBR (a combination of 15 mg/kg CCP and 50 mg/kg BBR) were orally administered to the model mice for 10 days. Changes of body weight, disease activity index, colon length, organ index, histopathological damage, expression of cytokines, and intestinal tight junction proteins were determined to evaluate the therapeutic effects. 16S rDNA sequencing, targeted short-chain fatty acid metabolomics, qPCR, and western blotting were performed to elucidate the potential mechanism.RESULTS: Both CCP and BBR alleviated UC via improving colon pathological damage, inhibiting the inflammatory response, and regulating the expression of intestinal tight junction proteins. The combination of CCP with BBR showed a more substantial therapeutic effect via increasing the relative abundance of short-chain fatty acids (SCFAs) producing bacteria, thereby increasing the contents of SCFAs in vivo and activating AhR/IL-22 pathway.CONCLUSION: The combination of CCP and BBR showed a synergistic effect on the therapy of chronic UC and the mechanism was associated with regulating gut microbiota and activating AhR/IL-22 pathway.PMID:37595814 | DOI:10.1016/j.jep.2023.117050
Possible role of the gut microbiome in mediating the beneficial effects of the six-herbal formulation STW 5-II on digestive health
Phytomedicine. 2023 Aug 4;119:154996. doi: 10.1016/j.phymed.2023.154996. Online ahead of print.ABSTRACTBACKGROUND: STW 5-II is a combination of six herbal extracts with clinically proven efficacy in functional dyspepsia (FD) and irritable bowel syndrome (IBS). STW 5-II contains a wide variety of secondary plant constituents that may interact with the human gut microbiome. In addition to complex carbohydrates, secondary plant metabolites, such as polyphenols, are known to exert prebiotic-like effects.PURPOSE: This study aimed to assess the bidirectional interactions between STW 5-II and the human gut microbiome.METHODS: STW 5-II was incubated with human fecal microbiota in a short-term colonic model. In the samples, the impact of STW 5-II on microbial fermentation capacity (pH, gas production), short chain fatty acid (SCFA) production, and microbial composition (Illumina 16S rRNA gene sequencing) was analyzed. In addition, the biotransformation of STW 5-II constituents by the fecal microbiota was assessed by UHPLCHRMS-based metabolite profiling. Furthermore, Caco-2/THP1 co-culture assay was used to explore the effect on gut barrier integrity and inflammatory markers.RESULTS: Fermentation of STW 5-II by fecal microbiota led to consistent changes in pH and gas production and increased production of SCFAs (acetate, propionate, and butyrate). STW 5-II promoted the enrichment of Bifidobacteriaceae, Lachnospiraceae, Ruminococcaceae, Erysipelotrichaceae, and Eggerthellaceae and suppressed the growth of pathogenic species from the Enterobacteriaceae family. In Caco2/THP1 culture, treatment with STW 5-II-incubated samples resulted in significantly increased transepithelial electrical resistance, indicating enhanced barrier function. Among inflammatory markers, STW 5-II-incubated samples increased LPS-induced secretion of the anti-inflammatory cytokine IL-10, as well as NF-κB activity, and significantly decreased the secretion of the pro-inflammatory chemokine MCP-1. UHPLCHRMS analysis identified 110 constituents of STW 5-II with changed levels during incubation with fecal microbiota: 63 constituents that were metabolized, 22 intermittently increased metabolites, and 25 final metabolites, including compounds with established anti-inflammatory activity, such as 18β-glycyrrhetinic acid.CONCLUSION: These findings indicate a microbiome-mediated digestive health-promoting effect of STW 5-II via three different routes, namely enhanced microbial SCFA production, microbial production of potentially bioactive metabolites from STW 5-II constituents, and prebiotic-like action by promoting the proliferation/growth of beneficial bacteria.PMID:37595389 | DOI:10.1016/j.phymed.2023.154996
A pathogen-specific isotope tracing approach reveals metabolic activities and fluxes of intracellular Salmonella
PLoS Biol. 2023 Aug 18;21(8):e3002198. doi: 10.1371/journal.pbio.3002198. Online ahead of print.ABSTRACTPathogenic bacteria proliferating inside mammalian host cells need to rapidly adapt to the intracellular environment. How they achieve this and scavenge essential nutrients from the host has been an open question due to the difficulties in distinguishing between bacterial and host metabolites in situ. Here, we capitalized on the inability of mammalian cells to metabolize mannitol to develop a stable isotopic labeling approach to track Salmonella enterica metabolites during intracellular proliferation in host macrophage and epithelial cells. By measuring label incorporation into Salmonella metabolites with liquid chromatography-mass spectrometry (LC-MS), and combining it with metabolic modeling, we identify relevant carbon sources used by Salmonella, uncover routes of their metabolization, and quantify relative reaction rates in central carbon metabolism. Our results underline the importance of the Entner-Doudoroff pathway (EDP) and the phosphoenolpyruvate carboxylase for intracellularly proliferating Salmonella. More broadly, our metabolic labeling strategy opens novel avenues for understanding the metabolism of pathogens inside host cells.PMID:37594988 | DOI:10.1371/journal.pbio.3002198
Eco-Metabolomics Applied to the Chemical Ecology of Poison Frogs (Dendrobatoidea)
J Chem Ecol. 2023 Aug 18. doi: 10.1007/s10886-023-01443-0. Online ahead of print.ABSTRACTAmphibians are one of the most remarkable sources of unique natural products. Biogenic amines, peptides, bufodienolides, alkaloids, and volatile organic compounds have been characterized in different species. The superfamily Dendrobatoidea represents one of the most enigmatic cases of study in chemical ecology because their skin secretome is composed by a complex mixture (i.e. cocktail) of highly lethal and noxious unique alkaloid structures. While chemical defences from dendrobatoids (families Dendrobatidae and Aromobatidae) have been investigated employing ecological, behavioral, phylogenetic and evolutionary perspectives, studies about the analytical techniques needed to perform the chemical characterization have been neglected for many years. Therefore, our aim is to summarize the current methods applied for the characterization of chemical profiles in dendrobatoids and to illustrate innovative Eco-metabolomics strategies that could be translated to this study model. This approach could be extended to natural products other than alkaloids and implemented for the chemical analysis of different species of dendrobatoids employing both low- and high-resolution mass spectrometers. Here, we overview important biological features to be considered, procedures that could be applied to perform the chemical characterization, steps and tools to perform an Eco-metabolomic analysis, and a final discussion about future perspectives.PMID:37594619 | DOI:10.1007/s10886-023-01443-0