RESUMEN
In silico prediction of xenobiotic metabolism is an important strategy to accelerate the drug discovery process, as candidate compounds often fail in clinical phases due to their poor pharmacokinetic profiles. Here we present MetaQM, a dataset of quantum-mechanical (QM) optimized metabolic substrates, including force field parameters, electronic and physicochemical properties. MetaQM comprises 2054 metabolic substrates extracted from the MetaQSAR database. We provide QM-optimized geometries, General Amber Force Field (FF) parameters for all studied molecules, and an extended set of structural and physicochemical descriptors as calculated by DFT and PM7 methods. The generated data can be used in different types of analysis. FF parameters can be applied to perform classical molecular mechanics calculations as exemplified by the validating molecular dynamics simulations reported here. The calculated descriptors can represent input features for developing improved predictive models for metabolism and drug design, as exemplified in this work. Finally, the QM-optimized molecular structures are valuable starting points for both ligand- and structure-based analyses such as pharmacophore mapping and docking simulations.
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Teoría Cuántica , Simulación de Dinámica Molecular , Xenobióticos/química , Xenobióticos/metabolismo , Descubrimiento de DrogasRESUMEN
D-penicillamine (PA) is the primary chelator of choice to treat Wilson disease (WD). There are limitations in obtaining comprehensive data on PA metabolites in biological specimens by conventional approaches. Hence, the aim of the present was to identify the major hepatic PA metabolites and draw clear conclusions of the drug's xenobiotic in WD. Urine samples were collected from children with hepatic WD (n = 63, aged 14.8 ± 4 years) 5 h after PA administration (16.3 ± 3.8 mg/kg/day) and age-matched healthy volunteers comprised as controls (n = 30). High-resolution 800 MHz nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry was applied to reveal unambiguous appraisals of different excretory by-products of PA metabolism. Four new products comprising penicillamine disulphide (PD), penicillamine cysteine disulphide (PCD), S-methyl penicillamine (SMP), and N-acetyl penicillamine (NAP) of PA xenobiotic metabolites were identified using high-resolution NMR spectroscopy. Quantitative levels of PCD and SMP were approximately three-fold higher than those of PD and NAP, respectively. High-resolution NMR identifies the major PA metabolites with certainty. Reduction, sulfation, and methylation are the predominant pathways of PA metabolism. There is a potential application for assessing therapeutic monitoring of chelation in hepatic WD.
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Degeneración Hepatolenticular , Penicilamina , Xenobióticos , Penicilamina/química , Penicilamina/uso terapéutico , Degeneración Hepatolenticular/tratamiento farmacológico , Degeneración Hepatolenticular/metabolismo , Humanos , Adolescente , Niño , Xenobióticos/metabolismo , Masculino , Femenino , Espectroscopía de Resonancia Magnética , Quelantes/química , Hígado/metabolismo , Hígado/efectos de los fármacosRESUMEN
To investigate the impact of chlorantraniliprole on Procambarus clarkii, acute toxicity tests were performed. Results indicated that 96 h post-exposure to chlorantraniliprole (60 mg/L) led to the separation of the hepatopancreas basement membrane, causing cell swelling, rupture, and vacuolation. Moreover, acid phosphatase (ACP) and alkaline phosphatase (AKP) activities exhibited divergent trends across four concentrations of chlorantraniliprole (0, 30, 60, and 90 mg/L). Hydrogen peroxide (H2O2) and catalase (CAT) levels significantly increased, while total superoxide dismutase (T-SOD) and malonaldehyde (MDA) activities decreased, indicating oxidative stress in the hepatopancreas. A total of 276 differentially expressed genes (DEGs) were identified, with 204 up-regulated and 72 down-regulated. Out of these, 114 DEGs were successfully annotated and classified into 99 pathways, with a primary focus on the cytochrome P450-mediated xenobiotic metabolism pathway. The DEGs enriched in this pathway, along with transcriptome data, were validated using quantitative-polymerase chain reaction. This study enhances the transcriptome database of P. clarkii and provides fundamental insights into its immune defense and antioxidant mechanisms. Additionally, it lays a theoretical foundation for future research on disease prevention in P. clarkii within rice-shrimp culture systems.
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Sistema Enzimático del Citocromo P-450 , Xenobióticos , ortoaminobenzoatos , Animales , ortoaminobenzoatos/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Xenobióticos/metabolismo , Inactivación Metabólica/genética , Astacoidea/genética , Astacoidea/efectos de los fármacos , Astacoidea/metabolismo , Transcriptoma/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Perfilación de la Expresión Génica , Hepatopáncreas/metabolismo , Hepatopáncreas/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacosRESUMEN
The gut microbial metalloenzymes play an important role in maintaining the balance between gut microbial ecosystem, human physiologically processes and immune system. The metals coordinated into active site contribute in various detoxification and defense strategies to avoid unfavourable environment and ensure bacterial survival in human gut. Metallo-ß-lactamase is a potent degrader of antibiotics present in periplasmic space of both commensals and pathogenic bacteria. The resistance to anti-microbial agents developed in this enzyme is one of the global threats for human health. The organophosphorus eliminator, organophosphorus hydrolases have evolved over a course of time to hydrolyze toxic organophosphorus compounds and decrease its effect on human health. Further, the redox stress responders namely superoxide dismutase and catalase are key metalloenzymes in reducing both endogenous and exogenous oxidative stress. They hold a great importance for pathogens as they contribute in pathogenesis in human gut along with reduction of oxidative stress. The in-silico study on these enzymes reveals the importance of point mutation for the evolution of these enzymes in order to enhance their enzyme activity and stability. Various mutation studies were conducted to investigate the catalytic activity of these enzymes. By using the "directed evolution" method, the enzymes involved in detoxification and defense system can be engineered to produce new variants with enhance catalytic features, which may be used to predict the severity due to multi-drug resistance and degradation pattern of organophosphorus compounds in human gut.
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Microbioma Gastrointestinal , Metaloproteínas , Especies Reactivas de Oxígeno , Xenobióticos , Xenobióticos/metabolismo , Humanos , Metaloproteínas/metabolismo , Metaloproteínas/química , Metaloproteínas/genética , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Retinoic acid receptors (RARs) are known as crucial endocrine receptors that could mediate a broad diversity of biological processes. However, the data on endocrine disrupting effects of emerging chemicals by targeting RAR (ant)agonism are far from sufficient. Herein, we investigated the RARα agonistic or antagonistic activities for 75 emerging chemicals of concern, and explored their interactions with this receptor. A recombinant two-hybrid yeast assay was used to examine the RARα activities of the test chemicals, wherein 7 showed effects of RARα agonism and 54 exerted potentials of RARα antagonism. The representative chemicals with RARα agonistic activities, i.e. 4-hydroxylphenol (4-HP) and bisphenol AF (BPAF), significantly increased the mRNA levels of CRABP2 and CYP26A1, while 4 select chemicals with RARα antagonistic potentials, including bisphenol A (BPA), tetrabromobisphenol A (TBBPA), 4-tert-octylphenol (4-t-OP), and 4-n-nonylphenol (4-n-NP), conversely decreased the transcriptional levels of the test genes. The in silico molecular docking analysis using 3 different approaches further confirmed the substantial binding between the chemicals with RARα activities and this nuclear receptor protein. This work highlights the promising strategy for screening endocrine-disrupting effects of emerging chemicals of concern by targeting RARα (ant)agonism.
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Disruptores Endocrinos , Receptor alfa de Ácido Retinoico , Xenobióticos , Receptor alfa de Ácido Retinoico/metabolismo , Receptor alfa de Ácido Retinoico/genética , Humanos , Simulación del Acoplamiento Molecular , Simulación por Computador , Receptores de Ácido Retinoico/metabolismoRESUMEN
Phytophagous insects are more predisposed to evolve insecticide resistance than other insect species due to the "preadaptation hypothesis". Cytochrome P450 monooxygenases have been strongly implicated in insecticide and phytochemical detoxification in insects. In this study, RNA-seq results reveal that P450s of Spodoptera litura, especially the CYP3 clan, are dominant in cyantraniliprole, nicotine, and gossypol detoxification. The expression of a Malpighian tubule-specific P450 gene, SlCYP9A75a, is significantly upregulated in xenobiotic treatments except α-cypermethrin. The gain-of-function and loss-of-function analyses indicate that SlCYP9A75a contributes to cyantraniliprole, nicotine, and α-cypermethrin tolerance, and SlCYP9A75a is capable of binding to these xenobiotics. This study indicates the roles of inducible SlCYP9A75a in detoxifying man-made insecticides and phytochemicals and may provide an insight into the development of cross-tolerance in omnivorous insects.
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Sistema Enzimático del Citocromo P-450 , Proteínas de Insectos , Resistencia a los Insecticidas , Insecticidas , Túbulos de Malpighi , Spodoptera , Xenobióticos , Animales , Spodoptera/genética , Spodoptera/efectos de los fármacos , Spodoptera/enzimología , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Xenobióticos/metabolismo , Insecticidas/farmacología , Túbulos de Malpighi/metabolismo , Túbulos de Malpighi/enzimología , Túbulos de Malpighi/efectos de los fármacos , Resistencia a los Insecticidas/genética , Inactivación Metabólica/genética , Larva/crecimiento & desarrollo , Larva/genética , Larva/efectos de los fármacosRESUMEN
Survival strategies of human-associated microbes to drug exposure have been mainly studied in the context of bona fide pathogens exposed to antibiotics. Less well understood are the survival strategies of non-pathogenic microbes and host-associated commensal communities to the variety of drugs and xenobiotics to which humans are exposed. The lifestyle of microbial commensals within complex communities offers a variety of ways to adapt to different drug-induced stresses. Here, we review the responses and survival strategies employed by gut commensals when exposed to drugs-antibiotics and non-antibiotics-at the individual and community level. We also discuss the factors influencing the recovery and establishment of a new community structure following drug exposure. These survival strategies are key to the stability and resilience of the gut microbiome, ultimately influencing the overall health and well-being of the host.
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Antibacterianos , Bacterias , Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/efectos de los fármacos , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Xenobióticos/farmacología , Simbiosis , Tracto Gastrointestinal/microbiología , Tracto Gastrointestinal/efectos de los fármacos , Farmacorresistencia Bacteriana , Interacciones Microbiota-Huesped/efectos de los fármacosRESUMEN
The allele and genotype frequencies of the polymorphic loci CYP1A1 (rs1048943), GSTP1 (rs1695 and rs1138272), GSTM1, and GSTT1 genes were studied in 517 men: in 389 accumulated mercury pollution liquidators (207 firefighters of the Ministry of the Russian Federation for Civil Defence, Emergencies and Elimination of Consequences of Natural Disasters and 182 employees of the Federal Environmental Operator) and 128 former workers (82 patients in the delayed period of chronic mercury intoxication and 46 individuals contacted with mercury and had no chronic mercury intoxication). We found differences in the frequencies of AA and AG genotypes in groups of former workers (χ2=6.96, p=0.008) for the polymorphic locus rs1048943, while the AG-CYP1A1 genotype was characterized by a 5.5-fold decrease in the odds ratio for the development of chronic mercury intoxication (OR=0.18, p=0.0041). An unfavorable combination of genotypes of the studied polymorphic loci increases the risk of undesirable health effects.
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Citocromo P-450 CYP1A1 , Glutatión Transferasa , Mercurio , Exposición Profesional , Xenobióticos , Humanos , Masculino , Glutatión Transferasa/genética , Glutatión Transferasa/metabolismo , Mercurio/toxicidad , Exposición Profesional/efectos adversos , Adulto , Xenobióticos/metabolismo , Citocromo P-450 CYP1A1/genética , Gutatión-S-Transferasa pi/genética , Persona de Mediana Edad , Intoxicación por Mercurio/genética , Frecuencia de los Genes/genética , Biotransformación/genética , Genotipo , Polimorfismo de Nucleótido Simple/genética , Federación de Rusia , Bomberos , AlelosRESUMEN
The pregnane X receptor (PXR) is a nuclear hormone receptor that plays a pivotal role in regulating gene expression in response to various ligands, particularly xenobiotics. In this context, the aim of this study was to shed light on the ligand affinity and functions of four NR1J1 paralogs identified in the marine mussel Mytilus galloprovincialis, employing a dual-luciferase reporter assay. To achieve this, the activation patterns of these paralogs in response to various toxins, including freshwater cyanotoxins (Anatoxin-a, Cylindrospermopsin, and Microcystin-LR, -RR, and -YR) and marine algal toxins (Nodularin, Saxitoxin, and Tetrodotoxin), alongside natural compounds (Saint John's Wort, Ursolic Acid, and 8-Methoxypsoralene) and microalgal extracts (Tetraselmis, Isochrysis, LEGE 95046, and LEGE 91351 extracts), were studied. The investigation revealed nuanced differences in paralog response patterns, highlighting the remarkable sensitivity of MgaNR1J1γ and MgaNR1J1δ paralogs to several toxins. In conclusion, this study sheds light on the intricate mechanisms of xenobiotic metabolism and detoxification, particularly focusing on the role of marine mussel NR1J1 in responding to a diverse array of compounds. Furthermore, comparative analysis with human PXR revealed potential species-specific adaptations in detoxification mechanisms, suggesting evolutionary implications. These findings deepen our understanding of PXR-mediated metabolism mechanisms, offering insights into environmental monitoring and evolutionary biology research.
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Toxinas Marinas , Mytilus , Receptor X de Pregnano , Animales , Receptor X de Pregnano/metabolismo , Receptor X de Pregnano/genética , Mytilus/metabolismo , Mytilus/genética , Humanos , Microcistinas/metabolismo , Microalgas/metabolismo , Microalgas/genética , Xenobióticos/metabolismo , Toxinas Bacterianas/metabolismo , Toxinas de CianobacteriasRESUMEN
BACKGROUND: How to screen and identify the effective components in the complex substance system is one of the core issues in achieving the modernization of traditional Chinese medicine (TCM) formulas. However, it is still challenging to systematically screen out the effective components from the hundreds or thousands of components in a TCM formula. PURPOSE: An innovative five-layer-funnel filtering mode stepwise integrating chemical profile, quantitative analysis, xenobiotic profile, network pharmacology and bioactivity evaluation was successfully presented to discover the effective components and implemented on a case study of Zhishi-Xiebai-Guizhi decoction (ZXG), a well-known TCM formula for coronary heart disease (CHD). METHODS: Initially, the chemical profile of ZXG was systemically characterized. Subsequently, the representative constituents were quantitatively analyzed. In the third step, the multi-component xenobiotics profile of ZXG was systemically delineated, and the prototypes absorbed into the blood were identified and designated as the primary bioavailable components. Next, an integrated network of "bioavailable components-CHD targets-pathways-therapeutic effects" was constructed, and the crucial bioavailable components of ZXG against CHD were screened out. Lastly, the bioactivities of crucial bioavailable components were further evaluated to pinpoint effective components. RESULTS: First of all, the chemical profile of ZXG was systemically characterized with the detection of 201 components. Secondly, 37 representative components were quantified to comprehensively describe its content distribution characteristics. Thirdly, among the quantified components, 24 bioavailable components of ZXG were identified based on the multi-component xenobiotic profile. Fourthly, an integrated network led to the identification of 11 crucial bioavailable components against CHD. Ultimately, 9 components (honokiol, magnolol, naringenin, magnoflorine, hesperidin, hesperetin, naringin, neohesperidin and narirutin) exhibiting myocardial protection in vitro were identified as effective components of ZXG for the first time. CONCLUSION: Overall, this innovative strategy successfully identified the effective components of ZXG for the first time. It could not only significantly contribute to elucidating the therapeutic mechanism of ZXG in the treatment of CHD, but also serve as a helpful reference for the systematic discovery of effective components as well as ideal quality markers in the quality assessment of TCM formulas.
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Enfermedad Coronaria , Medicamentos Herbarios Chinos , Medicina Tradicional China , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Medicina Tradicional China/métodos , Enfermedad Coronaria/tratamiento farmacológico , Animales , Farmacología en Red , Masculino , Xenobióticos , HumanosRESUMEN
The microbial community present in our intestines is pivotal for converting indigestible substances into vital nutrients and signaling molecules such as short-chain fatty acids (SCFAs). These compounds have considerable influence over our immune system and the development of diverse human diseases. However, ingested environmental contaminants, known as xenobiotics, can upset the delicate balance of the microbial gut community and enzymatic processes, consequently affecting the host organism. In our study, we employed an in vitro bioreactor model system based on the simplified human microbiome model (SIHUMIx) to investigate the direct effects of specific xenobiotics, such as perfluorooctanoic acid (PFOA), perfluorohexanoic acid (PFHxA) and perfluorobutanoic acid (PFBA) or bisphenol S (BPS) and bisphenol F (BPF), either individually or in combination, on the microbiota. We observed increased SCFA production, particularly acetate and butyrate, with PFAS exposure. Metaproteomics revealed pathway alterations across treatments, including changes in vitamin synthesis and fatty acid metabolism with BPX. This study underscores the necessity of assessing the combined effects of xenobiotics to better safeguard public health. It emphasizes the significance of considering adverse effects on the microbiome in the risk assessment of environmental chemicals.
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Compuestos de Bencidrilo , Ácidos Grasos Volátiles , Fluorocarburos , Microbioma Gastrointestinal , Xenobióticos , Humanos , Xenobióticos/toxicidad , Xenobióticos/metabolismo , Fluorocarburos/toxicidad , Microbioma Gastrointestinal/efectos de los fármacos , Ácidos Grasos Volátiles/metabolismo , Compuestos de Bencidrilo/toxicidad , Fenoles/toxicidad , Reactores Biológicos , Sulfonas/toxicidad , Contaminantes Ambientales/toxicidadRESUMEN
Contamination of aquatic environments has been steadily increasing due to human activities. The Pacific oyster Crassostrea gigas has been used as a key species in studies assessing the impacts of contaminants on human health and the aquatic biome. In this context, cytochrome P450 (CYPs) play a crucial role in xenobiotic metabolism. In vertebrates many of these CYPs are regulated by nuclear receptors (NRs) and little is known about the NRs role in C. gigas. Particularly, the CgNR5A represents a homologue of SF1 and LRH-1 found in vertebrates. Members of this group can regulate genes of CYPs involved in lipid/steroid metabolism, with their activity regulated by other NR, called as DAX-1, generating a NR complex on DNA response elements (REs). As C. gigas does not exhibit steroid biosynthesis pathways, CgNR5A may play other physiological roles. To clarify this issue, we conducted an in silico investigation of the interaction between CgNR5A and DNA to identify potential C. gigas CYP target genes. Using molecular docking and dynamics simulations of the CgNR5A on DNA molecules, we identified a monomeric interaction with extended REs. This RE was found in the promoter region of 30 CYP genes and also the NR CgDAX. When the upstream regulatory region was analyzed, CYP2C39, CYP3A11, CYP4C21, CYP7A1, CYP17A1, and CYP27C1 were mapped as the main genes regulated by CgNR5A. These identified CYPs belong to families known for their involvement in xenobiotic and lipid/steroid metabolism. Furthermore, we reconstructed a trimeric complex, previously proposed for vertebrates, with CgNR5A:CgDAX and subjected it to molecular dynamics simulations analysis. Heterotrimeric complex remained stable during the simulations, suggesting that CgDAX may modulate CgNR5A transcriptional activity. This study provides insights into the potential physiological processes involving these NRs in the regulation of CYPs associated with xenobiotic and steroid/lipid metabolism.
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Crassostrea , Sistema Enzimático del Citocromo P-450 , Receptores Citoplasmáticos y Nucleares , Crassostrea/genética , Animales , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Receptores Citoplasmáticos y Nucleares/química , Simulación del Acoplamiento Molecular , Regulación de la Expresión Génica , Simulación de Dinámica Molecular , Xenobióticos/metabolismoRESUMEN
Flavin-containing monooxygenases (FMOs), traditionally known for detoxifying xenobiotics, are now recognized for their involvement in endogenous metabolism. We recently discovered that an isoform of FMO, fmo-2 in Caenorhabditis elegans, alters endogenous metabolism to impact longevity and stress tolerance. Increased expression of fmo-2 in C. elegans modifies the flux through the key pathway known as One Carbon Metabolism (OCM). This modified flux results in a decrease in the ratio of S-adenosyl-methionine (SAM) to S-adenosyl-homocysteine (SAH), consequently diminishing methylation capacity. Here we discuss how FMO-2-mediated formate production during tryptophan metabolism may serve as a trigger for changing the flux in OCM. We suggest formate bridges tryptophan and OCM, altering metabolic flux away from methylation during fmo-2 overexpression. Additionally, we highlight how these metabolic results intersect with the mTOR and AMPK pathways, in addition to mitochondrial metabolism. In conclusion, the goal of this essay is to bring attention to the central role of FMO enzymes but lack of understanding of their mechanisms. We justify a call for a deeper understanding of FMO enzyme's role in metabolic rewiring through tryptophan/formate or other yet unidentified substrates. Additionally, we emphasize the identification of novel drugs and microbes to induce FMO activity and extend lifespan.
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Caenorhabditis elegans , Oxigenasas , Xenobióticos , Animales , Xenobióticos/metabolismo , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Oxigenasas/metabolismo , Oxigenasas/genética , Humanos , Triptófano/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , LongevidadRESUMEN
Bacillus subtilis ferredoxin:NADP+ oxidoreductase (BsFNR) is a thioredoxin reductase-type FNR whose redox properties and reactivity with nonphysiological electron acceptors have been scarcely characterized. On the basis of redox reactions with 3-acetylpyridine adenine dinucleotide phosphate, the two-electron reduction midpoint potential of the flavin adenine dinucleotide (FAD) cofactor was estimated to be -0.240 V. Photoreduction using 5-deazaflavin mononucleotide (5-deazaFMN) as a photosensitizer revealed that the difference in the redox potentials between the first and second single-electron transfer steps was 0.024 V. We examined the mechanisms of the reduction of several different groups of non-physiological electron acceptors catalyzed by BsFNR. The reactivity of quinones and aromatic N-oxides toward BsFNR increased when increasing their single-electron reduction midpoint redox potentials. The reactivity of nitroaromatic compounds was lower due to their lower electron self-exchange rate, but it exhibited the same trend. A mixed single- and two-electron reduction reaction was characteristic of quinones, whereas reactions involving nitroaromatics proceeded exclusively via the one-electron reduction reaction. The oxidation of FADH⢠to FAD is the rate-limiting step during the oxidation of fully reduced FAD. The calculated electron transfer distances in the reaction with nitroaromatics were close to those of other FNRs including the plant-type enzymes, thus demonstrating their similar active site accessibility to low-molecular-weight oxidants despite the fundamental differences in their structures.
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Bacillus subtilis , Ferredoxina-NADP Reductasa , Oxidación-Reducción , Ferredoxina-NADP Reductasa/metabolismo , Ferredoxina-NADP Reductasa/química , Bacillus subtilis/enzimología , Xenobióticos/metabolismo , Xenobióticos/química , Flavina-Adenina Dinucleótido/metabolismo , Flavina-Adenina Dinucleótido/química , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Potenciometría , Oxidantes/química , Quinonas/metabolismo , Quinonas/química , Transporte de ElectrónRESUMEN
Early-life exposure to natural and synthetic chemicals can impact acute and chronic health conditions. Here, a suspect screening workflow anchored on high-resolution mass spectrometry was applied to elucidate xenobiotics in breast milk and matching stool samples collected from Nigerian mother-infant pairs (n = 11) at three time points. Potential correlations between xenobiotic exposure and the developing gut microbiome, as determined by 16S rRNA gene amplicon sequencing, were subsequently explored. Overall, 12,192 and 16,461 features were acquired in the breast milk and stool samples, respectively. Following quality control and suspect screening, 562 and 864 features remained, respectively, with 149 of these features present in both matrices. Taking advantage of 242 authentic reference standards measured for confirmatory purposes of food bio-actives and toxicants, 34 features in breast milk and 68 features in stool were identified and semi-quantified. Moreover, 51 and 78 features were annotated with spectral library matching, as well as 416 and 652 by in silico fragmentation tools in breast milk and stool, respectively. The analytical workflow proved its versatility to simultaneously determine a diverse panel of chemical classes including mycotoxins, endocrine-disrupting chemicals (EDCs), antibiotics, plasticizers, perfluorinated alkylated substances (PFAS), and pesticides, although it was originally optimized for polyphenols. Spearman rank correlation of the identified features revealed significant correlations between chemicals of the same classification such as polyphenols. One-way ANOVA and differential abundance analysis of the data obtained from stool samples revealed that molecules of plant-based origin elevated as complementary foods were introduced to the infants' diets. Annotated compounds in the stool, such as tricetin, positively correlated with the genus Blautia. Moreover, vulgaxanthin negatively correlated with Escherichia-Shigella. Despite the limited sample size, this exploratory study provides high-quality exposure data of matched biospecimens obtained from mother-infant pairs in sub-Saharan Africa and shows potential correlations between the chemical exposome and the gut microbiome.
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Heces , Microbioma Gastrointestinal , Leche Humana , Humanos , Microbioma Gastrointestinal/efectos de los fármacos , Nigeria , Leche Humana/química , Leche Humana/microbiología , Lactante , Femenino , Heces/microbiología , Heces/química , Exposoma , Xenobióticos/análisis , Recién Nacido , ARN Ribosómico 16S , Contaminantes Ambientales/análisis , Adulto , MasculinoRESUMEN
In an attempt to discover and characterize the plethora of xenobiotic substances, this study investigates chemical compounds released into the environment with wastewater effluents. A novel non-targeted screening methodology based on ultra-high resolution Orbitrap mass spectrometry and nanoflow ultra-high performance liquid chromatography together with a newly optimized data-processing pipeline were applied to effluent samples from two state-of-the-art and one small wastewater treatment facility. In total, 785 molecular structures were obtained, of which 38 were identified as single compounds, while 480 structures were identified at a putative level. Most of these substances were therapeutics and drugs, present as parent compounds and metabolites. Using R packages Phyloseq and MetacodeR, originally developed for bioinformatics, significant differences in xenobiotic presence in the wastewater effluents between the three sites were demonstrated.
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Monitoreo del Ambiente , Aguas Residuales , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Aguas Residuales/química , Aguas Residuales/análisis , Dinamarca , Cromatografía Líquida de Alta Presión , Eliminación de Residuos Líquidos , Espectrometría de Masas/métodos , Xenobióticos/análisisRESUMEN
Environmental pollutants from different chemical families may reach the gut microbiome, where they can be metabolized and transformed. However, how our gut symbionts respond to the exposure to environmental pollution is still underexplored. In this observational, cohort study, we aim to investigate the influence of environmental pollution on the gut microbiome composition and potential activity by shotgun metagenomics. We select as a case study a population living in a highly polluted area in Campania region (Southern Italy), proposed as an ideal field for exposomic studies and we compare the fecal microbiome of 359 subjects living in areas with high, medium and low environmental pollution. We highlight changes in gut microbiome composition and functionality that were driven by pollution exposure. Subjects from highly polluted areas show higher blood concentrations of dioxin and heavy metals, as well as an increase in microbial genes related to degradation and/or resistance to these molecules. Here we demonstrate the dramatic effect that environmental xenobiotics have on gut microbial communities, shaping their composition and boosting the selection of strains with degrading capacity. The gut microbiome can be considered as a pivotal player in the environment-health interaction that may contribute to detoxifying toxic compounds and should be taken into account when developing risk assessment models. The study was registered at ClinicalTrials.gov with the identifier NCT05976126.
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Contaminantes Ambientales , Heces , Microbioma Gastrointestinal , Xenobióticos , Humanos , Microbioma Gastrointestinal/efectos de los fármacos , Xenobióticos/metabolismo , Contaminantes Ambientales/metabolismo , Contaminantes Ambientales/toxicidad , Femenino , Masculino , Heces/microbiología , Italia , Adulto , Persona de Mediana Edad , Exposición a Riesgos Ambientales/efectos adversos , Metagenómica/métodos , Bacterias/genética , Bacterias/clasificación , Bacterias/metabolismo , Bacterias/efectos de los fármacos , Bacterias/aislamiento & purificación , Estudios de Cohortes , Metales Pesados/toxicidad , Metales Pesados/metabolismo , Anciano , Contaminación Ambiental/efectos adversos , Biodegradación AmbientalRESUMEN
Arguably the most famous principle of toxicology is "The dose makes the poison" formulated by Paracelsus in the 16th century. Application of the Paracelsus's principle to mechanistic toxicology may be challenging as one compound may affect many molecular pathways at different doses with different and often nonlinear dose-response relationships. As a result, many mechanistic studies of environmental and occupational compounds use high doses of xenobiotics motivated by the need to see a clear signal indicating disruption of a particular molecular pathway. This approach ignores the possibility that the same xenobiotic may affect different molecular mechanism(s) at much lower doses relevant to human exposures. To amend mechanistic toxicology with a simple and concise guiding principle, I suggest recontextualization of Paracelsus's following its letter and spirit: "The dose disrupts the pathway". Justification of this statement includes observations that many environmental and occupational xenobiotics affect a broad range of molecular cascades, that most molecular pathways are sensitive to chemical exposures, and that different molecular pathways are sensitive to different doses of a chemical compound. I suggest that this statement may become a useful guidance and educational tool in a range of toxicological applications, including experimental design, comparative analysis of mechanistic hypotheses, evaluation of the quality of toxicological studies, and risk assessment.
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Relación Dosis-Respuesta a Droga , Toxicología , Xenobióticos , Xenobióticos/toxicidad , Toxicología/métodos , Humanos , Animales , Transducción de Señal/efectos de los fármacos , Medición de RiesgoRESUMEN
Nasal xenobiotic metabolizing enzymes (XMEs) are important for the sense of smell because they influence odorant availability and quality. Since the major part of the human nasal cavity is lined by a respiratory mucosa, we hypothesized that this tissue contributed to nasal odorant metabolism through XME activity. Thus, we built human respiratory tissue models and characterized the XME profiles using single-cell RNA sequencing. We focused on the XMEs dicarbonyl and l-xylulose reductase, aldehyde dehydrogenase (ALDH) 1A1, and ALDH3A1, which play a role in food odorant metabolism. We demonstrated protein abundance and localization in the tissue models and showed the metabolic activity of the corresponding enzyme families by exposing the models to the odorants 3,4-hexandione and benzaldehyde. Using gas chromatography coupled with mass spectrometry, we observed, for example, a significantly higher formation of the corresponding metabolites 4-hydroxy-3-hexanone (39.03 ± 1.5%, p = 0.0022), benzyl alcohol (10.05 ± 0.88%, p = 0.0008), and benzoic acid (8.49 ± 0.57%, p = 0.0004) in odorant-treated tissue models compared to untreated controls (0 ± 0, 0.12 ± 0.12, and 0.18 ± 0.18%, respectively). This is the first study that reveals the XME profile of tissue-engineered human respiratory mucosa models and demonstrates their suitability to study nasal odorant metabolism.
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Odorantes , Mucosa Respiratoria , Humanos , Odorantes/análisis , Mucosa Respiratoria/metabolismo , Modelos Biológicos , Cromatografía de Gases y Espectrometría de Masas , Familia de Aldehído Deshidrogenasa 1/metabolismo , Familia de Aldehído Deshidrogenasa 1/genética , Xenobióticos/metabolismoRESUMEN
Enzymes play an increasingly important role in improving the benignity and efficiency of chemical production, yet the diversity of their applications lags heavily behind chemical catalysts as a result of the relatively narrow range of reaction mechanisms of enzymes. The creation of enzymes containing non-biological functionalities facilitates reaction mechanisms outside nature's canon and paves the way towards fully programmable biocatalysis1-3. Here we present a completely genetically encoded boronic-acid-containing designer enzyme with organocatalytic reactivity not achievable with natural or engineered biocatalysts4,5. This boron enzyme catalyses the kinetic resolution of hydroxyketones by oxime formation, in which crucial interactions with the protein scaffold assist in the catalysis. A directed evolution campaign led to a variant with natural-enzyme-like enantioselectivities for several different substrates. The unique activation mode of the boron enzyme was confirmed using X-ray crystallography, high-resolution mass spectrometry (HRMS) and 11B NMR spectroscopy. Our study demonstrates that genetic-code expansion can be used to create evolvable enantioselective enzymes that rely on xenobiotic catalytic moieties such as boronic acids and access reaction mechanisms not reachable through catalytic promiscuity of natural or engineered enzymes.