Chlorinated Anthracenes Induced Pulmonary Immunotoxicity in 3D Coculture Spheroids Simulating the Lung Microenvironment.

Chlorinated anthracenes (Cl-Ants), persistent organic pollutants, are widely detected in the environment, posing potential lung toxicity risks due to frequent respiratory exposure. However, direct evidence and a comprehensive understanding of their toxicity mechanisms are lacking. Building on our prior findings of Cl-Ants' immunotoxic risks, this study developed a three-dimensional coculture spheroid model mimicking the lung's immune microenvironment. The objective is to explore the pulmonary immunotoxicity and comprehend its mechanisms, taking into account the heightened immune reactivity and frequent lung exposure of Cl-Ants. The results demonstrated that Cl-Ants exposure led to reduced spheroid size, increased macrophage migration outward, lowered cell viability, elevated 8-OHdG levels, disturbed anti-infection balance, and altered cytokine production. Specifically, the chlorine substituent number correlates with the extent of disruption of spheroid indicators caused by Cl-Ants, with stronger immunotoxic effects observed in dichlorinated Ant compared to those in monochlorinated Ant. Furthermore, we identified critical regulatory genes associated with cell viability (ALDOC and ALDOA), bacterial response (TLR5 and MAP2K6), and GM-CSF production (CEBPB). Overall, this study offers initial in vitro evidence of low-dose Cl-PAHs' pulmonary immunotoxicity, advancing the understanding of Cl-Ants' structure-related toxicity and improving external toxicity assessment methods for environmental pollutants, which holds significance for future monitoring and evaluation.

Effect of oxidative stress induced by 2,3,7,8- tetrachlorodibenzo-p-dioxin on DNA damage.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a highly toxic persistent organic pollutant (POP) that can induce DNA damage within cells. Although oxidative stress is one of the primary mechanisms causing DNA damage, its role in the process of TCDD-induced DNA damage remains unclear. In this study, the TCDD-induced production of reactive oxygen species (ROS) and the occurrence of DNA damage at the AP site were monitored simultaneously. Further investigation revealed that TCDD impaired the activities of superoxide dismutase (SOD) and catalase (CAT), compromising the cellular antioxidant defense system. Consequently, this led to an increase in the production of O2.- and NO, thus inducing DNA damage at the AP site under oxidative stress. Our findings were further substantiated by the upregulation of key genes in the base excision repair (BER) pathway and the absence of DNA AP site damage after inhibiting O2.- and NO. In addition, transcriptome sequencing revealed that TCDD induces DNA damage by upregulating genes associated with oxidative stress in the mitogen-activated protein kinase (MAPK), cyclic adenosine monophosphate (cAMP), and breast cancer pathways. This study provides important insights into the toxicity mechanisms of TCDD.

Portable Mass Spectrometry for On-site Detection of Hazardous Volatile Organic Compounds via Robotic Extractive Sampling.

Various hazardous volatile organic compounds (VOCs) are frequently released into environments during accidental events that cause many hazards to ecosystems and humans. Therefore, rapid, sensitive, and on-site detection of hazardous VOCs is crucial to understand their compositions, characteristics, and distributions in complex environments. However, manual handling of hazardous VOCs remains a challenging task, because of the inaccessible environments and health risk. In this work, we designed a quadruped robotic sampler to reach different complex environments for capturing trace hazardous VOCs using a needle trap device (NTD) by remote manipulation. The captured samples were rapidly identified by portable mass spectrometry (MS) within minutes. Rapid detection of various hazardous VOCs including toxicants, chemical warfare agents, and burning materials from different environments was successfully achieved using this robot-MS system. On-site detection of 83 typical hazardous VOCs was examined. Acceptable analytical performances including low detection limits (at subng/mL level), good reproducibility (relative standard deviation (RSD) < 20%, n = 6), excellent quantitative ability (R2 > 0.99), and detection speed (within minutes) were also obtained. Our results show that the robot-MS system has excellent performance including safety, controllability, applicability, and robustness under dangerous chemical conditions.

Rapid and sensitive determination of legacy and emerging per- and poly-fluoroalkyl substances with solid-phase microextraction probe coupled with mass spectrometry.

This study was designed to develop a rapid and sensitive method for quantifying legacy and emerging per- and polyfluoroalkyl substances (PFASs) in environmental samples with solid-phase microextraction (SPME) coupled with mass spectrometry (MS). An innovative SPME probe was fabricated via in situ polymerization, and the probe coating was optimized with response surface methodology to maximize the fluorine-fluorine interactions and electrostatic properties and ensure high selectivity for the target PFASs with enrichment factors of 48-491. The coupled SPME and MS provided a rapid and sensitive method for analyses of PFASs, with excellent linearity (r ≥ 0.9962) over the concentration range 0.001-1 µg/L and remarkably low detection limits of 0.1-13.0 ng/L. This method was used to analyze trace PFASs in tap water, river water, and wastewater samples and proved to be a simple and efficient analytical method for selective enrichment and detection of contaminants in the environment.

Environmentally relevant concentrations of 2,3,7,8-TCDD induced inhibition of multicellular alternative splicing and transcriptional dysregulation.

Alternative splicing (AS), found in approximately 95 % of human genes, significantly amplifies protein diversity and is implicated in disease pathogenesis when dysregulated. However, the precise involvement of AS in the toxic mechanisms induced by TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) remains incompletely elucidated. This study conducted a thorough global AS analysis in six human cell lines following TCDD exposure. Our findings revealed that environmentally relevant concentration (0.1 nM) of TCDD significantly suppressed AS events in all cell types, notably inhibiting diverse splicing events and reducing transcript diversity, potentially attributed to modifications in the splicing patterns of the inhibitory factor family, particularly hnRNP. And we identified 151 genes with substantial AS alterations shared among these cell types, particularly enriched in immune and metabolic pathways. Moreover, TCDD induced cell-specific changes in splicing patterns and transcript levels, with increased sensitivity notably in THP-1 monocyte, potentially linked to aberrant expression of pivotal genes within the spliceosome pathway (DDX5, EFTUD2, PUF60, RBM25, SRSF1, and CRNKL1). This study extends our understanding of disrupted alternative splicing and its relation to the multisystem toxicity of TCDD. It sheds light on how environmental toxins affect post-transcriptional regulatory processes, offering a fresh perspective for toxicology and disease etiology investigations.

Inner-Wall Coated Nanopipette Microextraction for Quantitative Analysis of Per- and Polyfluoroalkyl Substances in Single Cells Using Mass Spectrometry.

Per- and polyfluoroalkyl substances (PFASs) are a series of organic pollutants with potential cytotoxicity and biotoxicity. Accurate and sensitive detection of trace PFASs in single cells can provide insights into investigating their cytotoxicity, carcinogenicity, and mutagenicity. Here we report the development of an inner-wall coated nanopipette microextraction coupled with induced nanoelectrospray ionization mass spectrometry (InESI-MS) method and its application for rapid, sensitive, and accurate analysis of trace PFASs in single cells. A specially designed inner-wall coated nanopipette was prepared for sampling of the cytoplasm from a single cell, and the trace PFASs in the cytoplasm were selectively enriched into the coating via reversed-phase adsorption, ion bonding adsorption, and π-π interaction mechanisms. After the extraction, the cytoplasm was removed, and the enriched PFASs were then desorbed into some organic solvent, applying an alternating current (AC) voltage to the inner-wall coated nanopipette for InESI-MS analysis. The inner-wall coated nanopipette showed an exhaustive extraction to the trace PFASs in one single cell, and thus, the mass of each target analyte in the cytoplasm can be calculated via an internal standard calibration curve method, avoiding the measurement of ultrasmall volume cytoplasm for one single cell. By using the inner-wall coated nanopipette microextraction coupled with InESI-MS method, trace PFASs accumulated in the LO2 cells with pollutant exposure were successfully detected, and the accumulative behaviors and heterogeneities of PFASs in single cells were explored.

Nanospray Laser-Induced Plasma Ionization Mass Spectrometry for Rapid and Sensitive Analysis of Polycyclic Aromatic Hydrocarbons and Halogenated Derivatives.

Polycyclic aromatic hydrocarbons (PAHs) and halogenated derivatives are a series of environmental pollutants with potential toxicity and health risks on biosystems and the ecosystem. Rapid and sensitive analysis of trace PAHs and halogenated PAHs in complex environmental samples is a challenging topic for analytical science. Here we report the development of a nanospray laser-induced plasma ionization MS method for rapid and sensitive analysis of trace PAHs and halogenated PAHs under ambient and open-air conditions. A nanospray tip was applied for loading samples and placed pointing to the MS inlet, being a nanospray emitter with the application of a high voltage. A beam of laser was focused to induce energetic plasma between the nanospray emitter and the MS inlet for ionization of PAHs and halogenated PAHs for mass spectrometric analysis. Meanwhile, an inner-wall naphthyl-coated nanospray emitter was developed and applied as a solid-phase microextraction (SPME) probe for highly selective enrichment of trace PAHs and halogenated PAHs in complex environmental samples, and some organic solvent was applied to desorb the analytes for nanospray laser-induced plasma ionization MS analysis. Satisfactory linearity for each target PAH and halogenated PAH was obtained, with correlation coefficient values (r) no less than 0.9917. The method showed extremely high sensitivity for analysis of trace PAHs and halogenated PAHs in water, with limits of detection (LODs) and quantification (LOQs) of 0.0001-0.02 and 0.0003-0.08 µg/L, respectively. By using the inner-wall naphthyl-coated nanospray laser-induced plasma ionization MS method, sensitive detection of trace PAHs and halogenated PAHs in real sewage and wastewater samples was successfully achieved.

Slug-Flow Microextraction Mass Spectrometry for Enhanced Detection of Analytes in Human Tear Fluids using Noninvasive Microsampling and Nanoelectrospray Ionization via a Capillary.

In vivo noninvasive sampling and sensitive analysis of human tear fluids at the microliter level is an important but challenging task in investigating eye health. In this work, capillary microsampling coupled with slug-flow microextraction mass spectrometry (SFME-MS) was developed for enhanced detection of analytes in human tear fluids. As low as 1.0 µL of human tear fluid could be directly sampled using a capillary, and extraction/spray solvent was then loaded into the capillary to perform slug-flow microextraction and direct nanoelectrospray ionization (nESI) of analytes. All analytical procedures, including tear microsampling, microextraction, and ionization of analytes, were performed using a capillary. Enhanced detection of therapeutic drugs and disease biomarkers in human tear fluids was successfully demonstrated. Acceptable analytical performances including sensitivity, reproducibility, and quantitation were obtained. It is found that the use of SFME could improve the nESI-MS detection of trace analytes over 100-fold that depends on the chemical properties of analytes. Overall, this study showed that SFME-nESI-MS is a highly effective method for enhanced detection of trace analytes in tear fluids and is expected to be a potentially powerful tool in significant biological and clinical applications.

Exploring the Accumulation Behavior and Heterogeneity of Perfluorooctanesulfonic Acid in Zebrafish Primary Organ Cells by Single-Cell Mass Cytometry.

Perfluorooctanesulfonic acid (PFOS) is a commonly found environmental pollutant with potential toxicity and health risks to biosystems and ecosystems. Study of the accumulation behavior and heterogeneity of PFOS in biological primary organ cells provides us significant insights to explore its cytotoxicity, carcinogenicity, and mutagenicity. Here a single-cell mass cytometry system was established for the high-throughput analysis of trace PFOS and the exploration of its accumulation behavior and heterogeneity in zebrafish primary organ cells. The single-cell mass cytometry system applied a ∼25 µm constant-inner-diameter capillary as the single-cell generation and transportation channel with an etched tip-end of 40 µm as the nanoelectrospray emitter for mass spectrometric analysis. The single-cell mass cytometry system showed satisfactory semiquantitative performance and sensitivity for analysis of PFOS in single cells, with a high detection throughput of ∼35 cells/min. Subsequently, the liver, intestine, heart, and brain from PFOS-exposed zebrafish (100 pg/µL, 28 days) were dissociated and prepared as cell suspensions, and the cell suspensions were introduced into the single-cell mass cytometry system for high-throughput analysis of PFOS in individual primary organ cells. Significant cellular accumulation heterogeneities were observed, with the highest content in liver cells, followed by intestine cells, then heart cells, and the lowest in brain cells. In addition, the dynamics of PFOS in the zebrafish liver, intestine, heart, and brain cells showed typical violin plot distributions and were well-described using a gamma (γ) function.

Efflux transport proteins of Tetrahymena thermophila play important roles in resistance to perfluorooctane sulfonate exposure.

The biotoxicity of perfluorooctane sulfonate (PFOS) has been a concern. However, the effects of PFOS on Tetrahymena thermophila, a unicellular model organism, remain unclear. This study aimed to investigate the toxicity and detoxification mechanism of PFOS in this protozoan. PFOS did not show prominent toxic effects on T. thermophila. Cell viability of T. thermophila can be concentration-dependently increased by PFOS. PFOS also increased the stability of cell membranes and the activity of lysosomes. However, PFOS inhibited efflux transporter activities. Most of the PFOS amount remained in the culture medium during the culture periods. Only a low amount of PFOS was absorbed by cells, where PFOS molecules were mainly combined with membrane proteins. The expressions of four membrane protein genes involved in transporting xenobiotics were analyzed by real time-PCR. The gene abcg25 was significantly up-regulated. The growth of abcg25 gene knockout protozoans under PFOS treatment was slightly inhibited. However, the amount of PFOS adsorbed by the knockout protozoans showed no significant difference from the Wild-type protozoans. We concluded that the ABCG25 protein might play a key role in preventing PFOS from entering the cell or being exported from the cells to protect T. thermophila against PFOS. However, ABCG25 was not the only membrane protein able to bind with PFOS.

Development of a Repair Enzyme Fluorescent Probe to Reveal the Intracellular DNA Damage Induced by Benzo[a]pyrene in Living Cells.

Pollutant exposure causes a series of DNA damage in cells, resulting in the initiation and progression of diseases and even cancers. An investigation of the DNA damage induced by pollutants in living cells is significant to evaluate the cytotoxicity, genotoxicity, and carcinogenicity of environmental exposure, providing critical insight in the exploration of the etiologies of diseases. In this study, we develop a repair enzyme fluorescent probe to reveal the DNA damage caused by an environmental pollutant in living cells by single-cell fluorescent imaging of the most common base damage repair enzyme named human apurinic/apyrimidinic endonuclease 1 (APE1). The repair enzyme fluorescent probe is fabricated by conjugation of an APE1 high affinity DNA substrate on a ZnO2 nanoparticle surface to form a ZnO2@DNA nanoprobe. The ZnO2 nanoparticle serves as both a probe carrier and a cofactor supplier, releasing Zn2+ to activate APE1 generated by pollutant exposure. The AP-site in the DNA substrate of the fluorescent probe is cleaved by the activated APE1, releasing fluorophore and generating fluorescent signals to indicate the position and degree of APE1-related DNA base damage in living cells. Subsequently, the developed ZnO2@DNA fluorescent probe is applied to investigate the APE1-related DNA base damage induced by benzo[a]pyrene (BaP) in living human hepatocytes. Significant DNA base damage by BaP exposure is revealed, with a positive correlation of the damage degree with exposure time in 2-24 h and the concentration in 5-150 µM, respectively. The experimental results demonstrate that BaP has a significant effect on the AP-site damage, and the degree of DNA base damage is time-dependent and concentration-dependent.

Single-cell transcriptomic analysis reveals heterogeneity of the patterns of responsive genes and cell communications in liver cell populations of zebrafish exposed to polystyrene nanoplastics.

Nanoplastics (NPs) are a group of emerging environmental pollutants with potential toxicity and health risk on biosystem and ecosystem. Great efforts have been devoted to describing the uptake, distribution, accumulation, and toxicity of NPs at various aquatic organisms; however, the heterogeneous response patterns in zebrafish (Danio rerio) liver cell populations caused by NP exposure have not yet been clarified. Investigation of the heterogeneous response patterns in zebrafish liver cell populations after NPs exposure provides us significances to explore the NP cytotoxicity. In this article, the heterogeneous response patterns in zebrafish liver cell populations after polystyrene (PS)-NPs exposure were studied. Significantly increased content of malondialdehyde and decreased levels of catalase and glutathione were observed, indicating the oxidative damage of zebrafish liver induced by PS-NPs exposure. Afterwards, the liver tissues were enzymatically dissociated and used for single-cell transcriptomic (scRNA-seq) analysis. Nine cell types were identified based on unsupervised cell cluster analysis followed by their marker genes. Hepatocytes were the cell type most impacted by PS-NP exposure, and heterogeneous response patterns of male and female hepatocytes were observed. The PPAR signaling pathway was up-regulated in hepatocytes from both male and female zebrafish. Lipid metabolism-related functions were altered more notably in male-derived hepatocytes, while female-derived hepatocytes were more sensitive to estrogen stimulus and mitochondria. Macrophages and lymphocytes were also highly responsive cell types, with specific immune pathways activated to suggest immune disruption after exposure. Oxidation-reduction process and immune response were significantly altered in macrophages, and oxidation-reduction process, ATP synthesis, and DNA binding were most altered in lymphocytes. Our study not only integrates scRNA-seq with toxicology effects to identify highly sensitive and specific populations of responding cells, revealing highly specialized interactions between parenchymal and non-parenchymal cells and expanding our current understanding of PS-NPs toxicity, but also highlights the importance of cellular heterogeneity in environmental toxicology.

Polystyrene microplastics significantly facilitate influenza A virus infection of host cells.

Microplastics (MPs) are emerging pollutants which exist in various environments and pose a potential threat to human health. However, the effect of MP on respiratory pathogens-infected organisms is unknown. In order to explore the effect of MP on respiratory pathogen infection, we studied the effect of polystyrene microplastics (PS) on influenza A virus (IAV)-infected A549 cells. Western blot, qPCR, and viral plaque assay demonstrated that PS could promote IAV infection. Further study by bioluminescence imaging showed that a large number of IAV could be enriched on PS and entered cells through endocytosis. Meanwhile, the expression of IFITM3 in cells was significantly reduced. In addition, our results showed that PS down-regulated IRF3 and its active form P-IRF3 by down-regulating RIG-I and inhibiting TBK1 phosphorylation activation, which then significantly reduced IFN-ß expression and affected the cellular innate antiviral immune system. Taken together, our results indicate the potential threat of MPs to respiratory diseases caused by IAV and provide new insights into human health protection.

Computer simulation and design of DNA-nanoprobe for fluorescence imaging DNA repair enzyme in living cells.

In situ imaging of DNA repair enzymes in living cells gives important insights to diagnosis and explore the formation of various diseases. Fluorescent probes have become a powerful and widely used technique for their high sensitivity and real-time capabilities, but empirical design and optimization of the corresponding probes can be blind and time-consuming. Herein, we report a strategy combining experimental studies with molecular simulation techniques for the rapid and rational design of sensitive fluorescent DNA probes for a representative DNA repair enzyme human apurinic/apyrimidinic endonuclease 1 (APE1). Extended-system Adaptive Biasing Force (eABF) was applied to study the interaction mechanism between DNA probes with respect to the enzyme, based on which a novel sensitive DNA probe was designed efficiently and economically. Product inhibition effect which significantly limited the sensitivity of existing probes was eliminated by decreasing the key interactions between DNA probe products and enzyme. Experimental mechanism studies showed the existence of intramolecular hairpin structure in DNA probes is important for the recognition of APE1 and elimination of product inhibition, which is in consistent with the simulations. The obtained fluorescent DNA nanoprobe (Nanoprobe N) showed a high sensitivity for APE1 with the detection limit as low as 0.5 U/L (∼0.018 pM), and the Nanoprobe N could effectively respond to the variation of APE1 within cells and distinguish cancer cells from normal cells. This work not only demonstrated the effectiveness of molecular simulations in probe design, but also provided a reliable platform for accurate imaging of APE1 and effectors screening at single-cell level.

Discovery of Potential Lipid Biomarkers for Human Colorectal Cancer by In-Capillary Extraction Nanoelectrospray Ionization Mass Spectrometry.

Discovering cancer biomarkers is of significance for clinical medicine and disease diagnosis. In this article, we develop an in-capillary extraction nanoelectrospray ionization mass spectrometry (ICE-nanoESI-MS) method to rapidly and in situ investigate human colorectal cancer for discovering lipid biomarkers. The ICE-nanoESI-MS method is performed using a tungsten microdissecting probe for in situ microsampling of surgical human colorectal cancer tumors and their paired distal noncancerous tissues during/after surgery. After sampling, the tungsten probe and the adhered tissues are inserted into a nanospray tip prefilled with some solvent for simultaneous in-capillary extraction and nanoESI-MS detection under ambient and open-air conditions. Online coupling of the Paternò-Büchi reaction and radical-direct fragmentation with ICE-nanoESI-MS is easily realized, which provides the opportunity to precisely determine carbon-carbon double bond (C═C) locations and stereospecific numbering (sn) positions of lipid biomarkers. Subsequently, a total of 12 pairs of colorectal cancer tumors and distal noncancerous tissues from different patients are investigated by our proposed ICE-nanoESI-MS method. A significant increase in lysophospholipids and fatty acids as well as a significant decrease in ceramides are discovered, and lysophospholipids are found as the potential biomarkers related to the formation and pathogenesis of human colorectal cancer.

Mapping the distribution of perfluoroalkyl substances in zebrafishes by liquid extraction surface analysis mass spectrometry.

Investigation on the distribution of persistent organic pollutants (POPs) in aquatic organisms is of great importance for exploring the biological toxicity and health risks of environmental pollutants. In this study, a liquid extraction surface analysis mass spectrometry (LESA-MS) method was developed for rapid and in situ analysis of the spatial distribution of perfluoroalkyl substances (PFASs) in zebrafish. By combining the high-precision automated moving platform of LESA device and the high-resolution MS, quantitative analysis of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) in zebrafish tissue section were easily achieved. A tissue-specific ionization efficiency factor (TSF) strategy was also proposed to correct the matrix effect in different parts of zebrafish tissue. By using the developed method, high sensitive and efficient imaging of PFOA and PFOS in zebrafish tissue was achieved, and the distributions of PFOA and PFOS in descending order were gills, organs, roes, pelvic fin, muscle, and brain. The experimental results demonstrated that the coupling of LESA-MS method with TFS strategy is an efficient and reliable approach for monitoring the content distribution of environmental pollutants in biological tissues.

In situ detection and imaging of lysophospholipids in zebrafish using matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry.

In this paper, a matrix-assisted laser desorption/ionization (MALDI) Fourier transform ion cyclotron resonance (FTICR) mass spectrometry (MS) (MALDI-FTICR-MS) imaging method was developed to rapid and in situ detect the spatial distribution of lysophospholipids (LPLs) in zebrafish. The combination of MALDI with ultrahigh-resolution FTICR-MS achieves the MS imaging of LPLs with a mass resolution up to 50 000, which allows accurate identification and clear spatial visualization of LPLs in complex biological tissues. A series of lysophosphatidylcholines (LPCs) was detected using positive ion detection mode, and their concentration differences and spatial distributions were clearly visualized in different parts of zebrafish tissue. The method is rapid, simple, and efficient, being a desirable way to understand the spatial distribution of LPLs in biosome.

Covalent Organic Frameworks-Based Solid-Phase Microextraction Probe for Rapid and Ultrasensitive Analysis of Trace Per- and Polyfluoroalkyl Substances Using Mass Spectrometry.

Rapid and ultrasensitive analysis of trace pollutants in complex matrices is of significance for understanding their environmental behaviors and toxic effects. Here a novel method based on the integration of solid-phase microextraction (SPME) and nanoelectrospray ionization mass spectrometry (nanoESI-MS) was developed for rapid and ultrasensitive analysis of trace per- and polyfluoroalkyl substances (PFASs) in environmental and biological samples. A novel SPME probe with F-functionalized covalent organic frameworks (COFs) coating was designed for highly selective enrichment of trace PFASs from complex samples. After extraction, the loaded COFs-SPME probe was directly appplied to nanoESI-MS analysis under ambient and open-air conditions. The method showed satisfactory linearities between 1 and 5000 ng/L for 14 investigated PFASs in water, with correlation coefficient values no less than 0.9952. The limits of detection and quantification varied from 0.02 to 0.8 ng/L and 0.06 to 3 ng/L, respectively. By using the proposed method, ultrasensitive detection of PFASs in environmental water and whole blood was successfully achieved.

Sacha inchi oil alleviates gut microbiota dysbiosis and improves hepatic lipid dysmetabolism in high-fat diet-fed rats.

Dietary ω-3 polyunsaturated fatty acids (PUFAs) are beneficial for humans against the development of hyperlipidaemia, but the underlying mechanisms are still poorly understood. Here, we demonstrated that oral consumption of sacha inchi oil, which is rich in α-linolenic acid, alleviated dyslipidemia, hepatic steatosis and inflammatory infiltration in high-fat diet (HFD)-fed rats. Sacha inchi oil administration reversed gut microbiota dysbiosis and altered the gut microbiota metabolome and in particular prevented bile acid dysmetabolism caused by a HFD. Sacha inchi oil intake ameliorated hepatic lipid dysmetabolism in HFD-fed rats, via potentiating the biosynthesis and reuptake of bile acids, reducing the de novo lipogenesis, promoting fatty acid beta-oxidation, and alleviating the dysregulation of glycerolipid, glycerophospholipid, and sphingolipid metabolisms. The results showed that dietary sacha inchi oil can alleviate gut microbiota dysbiosis and reduce lipid dysmetabolism in HFD rats, and provide novel insights into the molecular mechanisms by which plant-derived ω-3 PUFAs prevent the development of hyperlipidaemia.

Analysis of trace malachite green, crystal violet, and their metabolites in zebrafish by surface-coated probe nanoelectrospray ionization mass spectrometry.

Malachite green (MG) and crystal violet (CV) are the typical triphenylmethane dyes, which are recalcitrant molecules exerting mutagenic and carcinogenic effects on living organisms. Characterization of the residues of MG, CV, and their metabolites in biological organisms is of importance, especially for in vivo and in situ characterization. In this study, a method for determination of trace MG, CV, and their leuco metabolites in zebrafish by surface-coated probe nanoelectrospray ionization mass spectrometry (SCP-nanoESI-MS) was developed. A microscale solid-phase microextraction (SPME) probe was developed and used for extraction and enrichment of trace MG, CV, and their leuco metabolites in zebrafish after exposure. After that, the loaded SPME probe was directly employed for nanoESI-MS analysis under ambient and open-air conditions. Under the optimum conditions, the method demonstrated good linearity, with correlation coefficient values (r2) no less than 0.9925. The limits of detection and quantification were 0.014-0.023 ng mL-1 and 0.046-0.077 ng mL-1, respectively. By using the proposed method, the bioaccumulation of MG and CV in zebrafish was investigated, and the distribution of MG, CV, and their leuco metabolites in different organs of zebrafish was studied. MG, CV, and their leuco metabolites were all found in zebrafish tissues including brain, muscle, heart, and kidney after exposure, with highest concentration in intestine followed in ovary.