Identification and genetic characterization of a recently identified enterovirus C116 in China.

Enterovirus C116 (EV-C116) is a new member of the enterovirus C group which is closely associated with several infectious diseases. Although sporadic studies have detected EV-C116 in clinical samples worldwide, there is currently limited information available. In this study, two EV-C-positive fecal specimens were detected in apparently healthy children, which harbored low abundance, through meta-transcriptome sequencing. Based on the prototypes of several EV-Cs, two lineages were observed. Lineage 1 included many types that could not cause EV-like cytopathic effect in cell culture. Three genogroups of EV-C116 were divided in the maximum likelihood tree, and the two strains in this study (XZ2 and XZ113) formed two different lineages, suggesting that EV-C116 still diffuses worldwide. Obvious inter-type recombination events were observed in the XZ2 strain, with CVA22 identified as a minor donor. However, another strain (XZ113) underwent different recombination situations, highlighting the importance of recombination in the formation of EV-Cs biodiversity. The EV-C116 strains could propagate in rhabdomyosarcoma cell cultures at low titer; however, EV-like cytopathic effects were not observed. HEp-2, L20B, VERO, and 293T cell lines did not provide an appropriate environment for EV-C116 growth. These results challenge the traditional recognition of the uncultured nature of EV-C116 strains and explain the difficulty of clinical detection.

Glucose metabolism continuous deteriorating in male patients with human immunodeficiency virus accepted antiretroviral therapy for 156 weeks.

BACKGROUND: The dynamic characteristics of glucose metabolism and its risk factors in patients living with human immunodeficiency virus (PLWH) who accepted primary treatment with the efavirenz (EFV) plus lamivudine (3TC) plus tenofovir (TDF) (EFV + 3TC + TDF) regimen are unclear and warrant investigation. AIM: To study the long-term dynamic characteristics of glucose metabolism and its contributing factors in male PLWH who accepted primary treatment with the EFV + 3TC + TDF regimen for 156 wk. METHODS: This study was designed using a follow-up design. Sixty-one male treatment-naive PLWH, including 50 cases with normal glucose tolerance and 11 cases with prediabetes, were treated with the EFV + 3TC + TDF regimen for 156 wk. The glucose metabolism dynamic characteristics, the main risk factors and the differences among the three CD4+ count groups were analyzed. RESULTS: In treatment-naive male PLWH, regardless of whether glucose metabolism disorder was present at baseline, who accepted treatment with the EFV + 3TC + TDF regimen for 156 wk, a continuous increase in the fasting plasma glucose (FPG) level, the rate of impaired fasting glucose (IFG) and the glycosylated hemoglobin (HbA1c) level were found. These changes were not due to insulin resistance but rather to significantly reduced islet ß cell function, according to the homeostasis model assessment of ß cell function (HOMA-ß). Moreover, the lower the baseline CD4+ T-cell count was, the higher the FPG level and the lower the HOMA-ß value. Furthermore, the main risk factors for the FPG levels were the CD3+CD8+ cell count and viral load (VL), and the factors contributing to the HOMA-ß values were the alanine aminotransferase level, VL and CD3+CD8+ cell count. CONCLUSION: These findings provide guidance to clinicians who are monitoring FPG levels closely and are concerned about IFG and decreased islet ß cell function during antiretroviral therapy with the EFV + 3TC + TDF regimen for long-term application.

Comparative metabolism of THCA and THCV using UHPLC-Q-Exactive Orbitrap-MS.

Delta(9)-tetrahydrocannabinolic acid (THCA) and delta(9)-tetrahydrocannabivarin (THCV) are phytocannabinoids with a similar structure derived from Cannabis sativa and possess a variety of biological activities. However, the relationship between the metabolic characterisation and bioactivity of THCA and THCV remains elusive.To explore the relationship between the metabolism of THCA and THCV and their underlying mechanism of activity, human/mouse liver microsomes and mouse primary hepatocytes were used to compare the metabolic maps between THCA and THCV through comparative metabolomics. A total of 29 metabolites were identified containing 7 previously undescribed THCA metabolites and 10 previously undescribed THCV metabolites. Of these metabolites, THCA was transformed into an active metabolite of delta(9)-tetrahydrocannabinol (THC) in these three systems, while THCV was transformed into THC and CBD.Bioactivity assays indicated that all of these phytocannabinoids exhibited anti-inflammatory activity, but the effects of THCA and THCV were slightly different in macrophages RAW264.7. Prediction of ADMET lab demonstrated that THCV and its metabolites were endowed with the advantage of blood-brain barrier (BBB) penetration compared to THCA.In conclusion, this study highlighted that metabolism plays a critical role in the biological activity of phytocannabinoids.

Natural killer cell homing and trafficking in tissues and tumors: from biology to application.

Natural killer (NK) cells, a subgroup of innate lymphoid cells, act as the first line of defense against cancer. Although some evidence shows that NK cells can develop in secondary lymphoid tissues, NK cells develop mainly in the bone marrow (BM) and egress into the blood circulation when they mature. They then migrate to and settle down in peripheral tissues, though some special subsets home back into the BM or secondary lymphoid organs. Owing to its success in allogeneic adoptive transfer for cancer treatment and its "off-the-shelf" potential, NK cell-based immunotherapy is attracting increasing attention in the treatment of various cancers. However, insufficient infiltration of adoptively transferred NK cells limits clinical utility, especially for solid tumors. Expansion of NK cells or engineered chimeric antigen receptor (CAR) NK cells ex vivo prior to adoptive transfer by using various cytokines alters the profiles of chemokine receptors, which affects the infiltration of transferred NK cells into tumor tissue. Several factors control NK cell trafficking and homing, including cell-intrinsic factors (e.g., transcriptional factors), cell-extrinsic factors (e.g., integrins, selectins, chemokines and their corresponding receptors, signals induced by cytokines, sphingosine-1-phosphate (S1P), etc.), and the cellular microenvironment. Here, we summarize the profiles and mechanisms of NK cell homing and trafficking at steady state and during tumor development, aiming to improve NK cell-based cancer immunotherapy.

Transcriptome analysis of developing zebrafish (Danio rerio) embryo following exposure to Gaudichaudione H reveals teratogenicity and cardiovascular defects caused by abnormal iron metabolism.

Gaudichaudione H (GH), a caged polyprenylated xanthone from Garcinia plants, showed anti-cancer and anti-inflammatory effects in vitro. However, the in vivo toxicity of this compound has never been reported. The present study was aimed to address the toxic effects of Gaudichaudione H using zebrafish embryos and larvae as an in vivo test model. The zebrafish embryos were treated with GH having different concentrations (0, 0.28, 0.38 and 0.57 µg/mL). The results revealed that GH induces significant embryonic mortality, decreased heartbeat, cardiotoxicity, cardiovascular defects, increased apoptosis and decreased hemoglobinization in zebrafish embryos and larvae. According to transcriptome analysis, 1841 genes were significantly differentially expressed (1185 down-regulated and 656 up-regulated) after GH treatment. The main functions of these genes were related to iron metabolism pathways. The toxicity of GH on zebrafish embryonic development and cardiovascular may due to large amounts of downregulated genes involved in metabolic pathways and DEGs related to 'Iron ion binding' and 'Heme binding' functions.

[Research progress on effective components and mechanisms of anti-depressive Chinese medicine].

Since the pathogenesis of depression is complicated, the therapeutic effects of western medicine are poor accompanied by severe side effects. Chinese medicine has unique advantages in the treatment based on syndrome differentiation and contains many effective components against depression, including flavonoids, terpenes, phenylpropanoids, quinones, and alkaloids. These chemical components can delay the course of the disease, improve the curative effect, and reduce side effects of western medicine by regulating the biochemical abnormalities of monoamine neurotransmitters, brain tissue protein content, and internal environment as well as energy metabolism to make the treatment of Chinese medicine highlighted and recognized. This study systematically reviewed the effective components and mechanisms of anti-depressive Chinese medicine to inspire the rational development and utilization of new Chinese medicines against depression.

The clinical significance of transcription factor WD repeat and HMG-box DNA binding protein 1 in laryngeal squamous cell carcinoma and its potential molecular mechanism.

BACKGROUND: Currently, high expression of WD repeat and HMG-box DNA binding protein 1 (WDHD1) has been found in a variety of tumors; but there is no research has been conducted concerning the expression of WDHD1 in laryngeal squamous cell carcinoma (LSCC). Our purpose is to investigate the expression and the latent mechanism of WDHD1 in LSCC. METHODS: Firstly, 9 data sets from the Gene Expression Omnibus (GEO), The Cancer Genome Atlas (TCGA), and ArrayExpress were statistically analyzed to explore the expression of WDHD1 in LSCC; immunohistochemistry was performed in 79 LSCC tissues and 44 non-cancer tissues to further verify the result. In addition, the target gene of WDHD1 was predicted and immunohistochemistry was used to detect the expression of the target gene. The potential mechanism of WDHD1 in LSCC was investigated by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses and protein-protein interaction network (PPI). RESULTS: The WDHD1 mRNA was expressed at higher levels in the LSCC tissue than in the normal tissue (SMD=1.90, 95% CI=1.50-2.30); and the results of immunohistochemistry were consistent with the conclusion. Using chip-seq analysis, we found that S-phase kinase-associated protein 2 (Skp2) had a significant binding peak with WDHD1, and the expression of these two genes was significantly positively correlated. Immunohistochemistry showed that Skp2 was also highly expressed in LSCC. In addition, GO and KEGG analysis revealed the WDHD1 positively correlated genes was closely related to cell cycle, and PPI analysis identified 10 hub genes: COL7A1, COL4A2, COL4A1, COL4A6, COL11A1, COL5A2, COL1A1, COL13A1, COL8A1 and COL10A1, which may be critical to the progression of LSCC. CONCLUSIONS: WDHD1 was overexpressed in LSCC tissues. Meanwhile, WDHD1 and its target gene Skp2 for transcriptional regulation may play a role in the progression of LSCC by regulating the cell cycle.

Metabolomics reveals the role of isopentenyl group in coumarins metabolism.

Coumarins are a group of natural compounds commonly found in the families of Rutaceae and Umbelliferae. 7-Isopentenyloxycoumarin (ISC), auraptene (AUR), and umbelliprenin (UM) belong to prenyloxycoumarins (PYCs), which link isopentenyl, geranyl, and farnesyl group at C7 position, respectively. The substituent of 7-ethoxycoumarin (ETC) is the ethyl group. In this study, UPLC-ESI-QTOF-MS (ultra-performance liquid chromatography-electrospray ionization-quadrupole time of flight-MS)-based metabolomics was used to evaluate the in vivo and in vitro metabolism of PYCs. Results showed that ETC produced 10 known metabolites, and ISC was transformed into 17 metabolites in vivo and in vitro, which were undescribed compounds. A total of 35 AUR metabolites, including 34 undescribed metabolites were identified, and 21 metabolites were reported for the first time in UM. The results indicated that hydroxylation and N-acetylcysteine conjugation were the common metabolic reactions for PYCs. The metabolic rates of ETC, ISC, AUR and UM were 26%, 36%, 81%, and 38%, respectively, in human liver microsome, while they were 24%, 40%, 80%, and 37%, respectively, in mouse liver microsomes. In addition, recombinant cytochrome P450s (CYPs) screening showed that CYP1A1, 2C19, 3A4, and 3A5 were the major metabolic enzymes involved in the formation of hydroxylation metabolites. Together, these results suggest that the isopentenyl group plays an important role in the metabolism of PYCs.

Alkene Synthesis by Photo-Wolff-Kischner Reaction of Sulfur Ylides and N-Tosylhydrazones.

A visible-light-driven and room temperature photo-Wolff-Kischner reaction of sulfur ylides and N-tosylhydrazones has been developed for the first time to provide modular access to alkene synthesis. The high functional group tolerance and broad substrate scope were demonstrated by more than 60 examples. Both E- and Z-olefinic stereochemistry in the products could be controlled with excellent stereoselectivity. A series of mechanistic studies support that the reaction should proceed through a radical-carbanion crossover pathway, specifically involving addition of photo-generated sulfur ylide radical cations to N-tosylhydrazones to form carbanions and subsequent Wolff-Kischner process.

Discovery of quality markers in Rubus Chingii Hu using UPLC-ESI-QTOF-MS.

Raspberry, the fruit of Rubus Chingii Hu, has been used as a traditional Chinese medicine (TCM) to nourish kidney and strengthen Yang-qi. In order to determine the quality of raspberry, the quality markers (Q-markers) of raspberry that can improve renal function were investigated using UPLC-ESI-QTOF-MS in this study. The results of serum pharmacochemistry indicated that six components rutin, ellagic acid, kaempferol-3-rutinoside, astragalin, tiliroside, and goshonoside F5 in raspberry were absorbed into rat blood. The HEK293 cells treated with cisplatin were used to evaluate the kidney-protecting activity of these absorbed components. All these components could markedly inhibit cell damage induced by cisplatin and restore the levels of malondialdehyde (MDA) and catalase (CAT) in the cells, suggesting that these components may be the Q-markers of raspberry. More importantly, except for ellagic acid, other five Q-markers in raspberries from Dexing of Jiangxi province were higher than those from most of other areas. It is well known that Dexing raspberry is the Dao-di herbs raspberry used in the clinic of Chinese Medicine, demonstrating that these components could be used as Q-markers of raspberry. This study provides a reliable and valuable method for quality evaluation of raspberry.

Visible-Light-Driven Radical Multicomponent Reaction of 2-Vinylanilines, Sulfonyl Chlorides, and Sulfur Ylides for Synthesis of Indolines.

A visible-light-driven photoredox-catalyzed multicomponent reaction of 2-vinylanilines, sulfonyl chlorides, and sulfur ylides is described. This protocol features redox-neutral mild conditions, a broad substrate scope, and good functional group tolerance, providing access to various sulfonated 2,3-disubstituted indolines. The product can be transformed to a diverse range of functionalized indoles by a selective aromatization/nucleophilic substitution process. Mechanistic investigations suggest that both sulfonyl chlorides and sulfur ylides serve as radical sources, and the reaction proceeds through a sequential radical addition/addition/thermal SN2-substitution process.

Metabolic profiling of tyrosine kinase inhibitor nintedanib using metabolomics.

Nintedanib is a promising tyrosine kinase inhibitor for clinically treating idiopathic pulmonary fibrosis (IPF). Some clinical cases reported that nintedanib treatment can cause hepatotoxicity and myocardial toxicity. U. S. FDA warns the potential drug-drug interaction when it is co-administrated with other drugs. In order to understand the potential toxicity of nintedanib and avoid drug-drug interaction, the metabolism of nintedanib was systematically investigated in human liver microsomes and mice using metabolomics approach, and the toxicity of metabolites was predicted by ADMET lab. Nineteen metabolites were detected in vivo and in vitro metabolism, and 8 of them were undescribed. Calculated partition coefficients (Clog P) were used to distinguish the isomers of nintedanib metabolites in this study. The major metabolic pathways of nintedanib majorly included hydroxylation, demethylation, glucuronidation, and acetylation reactions. The ADMET prediction indicated that nintedanib was a substrate of the cytochrome P450 3A4 (CYP3A4) and P-glycoprotein (P-gp). And nintedanib and most of its metabolites might possess potential hepatotoxicity and cardiotoxicity. This study provided a global view of nintedanib metabolism, which could be used to understand the mechanism of adverse effects related to nintedanib and its potential drug-drug interaction.

Effects of long-term exposure to tenofovir disoproxil fumarate-containing antiretroviral therapy on renal function in HIV-positive Chinese patients.

BACKGROUND: The regimen containing tenofovir disoproxil fumarate (TDF)+lamivudine or emtricitabine + efavirenz remains the recommended first-line antiretroviral therapy (ART) by the WHO. Limited studies, however, have been conducted on the incidence of renal impairment among Chinese patients with long-term exposure to TDF-containing ART regimens. METHODS: We retrospectively analyzed 269 eligible patients who had no comorbidities and received TDF-containing ART from July 2014 to April 2015. TDF-related renal impairment was defined as a decrease of eGFR by >25% from baseline or eGFR <90 ml/min/1.73 m2. Decreased renal function was defined as a decrease of eGFR by > 10 mL/min/1.73 m2 from baseline. RESULTS: 97.0% of study patients were male (median age 29, eGFR 124.0 ml/min/1.73 m2). After 168-week of ART, renal impairment occurred in 7 patients (2.7%). The incidence of decreased renal function was significantly higher at Week 168 compared with that observed at Week 12 (24.8% vs 3.7%, p < 0.001). In generalized estimating equation analysis, patients receiving ART for 144-week (aOR4.1, 95%CI 2.0-8.4) and 168-week (aOR8.4, 95%CI 4.2-16.4) were more likely to develop decreased renal function compared with those receiving ART for 12-week, so were the patients with a weight <58 kg (aOR2.3, 95%CI 1.2-4.3) and 58-66 kg (aOR2.0, 95%CI 1.0-3.8) compared to those with a weight ≥67 kg. At 168-week, 41.0% of 100 patients examined had elevated urine ß2-microglobulin levels, which were negatively correlated with eGFR (r = -0.22, p = 0.02). CONCLUSIONS: TDF-related renal impairment remained rare in HIV-positive Chinese patients with a median age of 29 years who had no comorbidities. A lower weight and duration of ART were associated with decreased renal function.

[Significance of Peripheral Blood Lymphatic to Monocyte Ratio in the Progress of PGI-DLBCL].

OBJECTIVE: To explore the significance of lymphocyte to monocyte ratio (LMR) in the disease progress of primary gastrointestinal diffuse large B-cell lymphoma (PGI-DLBCL). METHODS: The clinical data of 43 patients diagnosed as PGI-DLBCL in our hospital from January 2011 to December 2015 were collected, and the disease progress was followed up. RESULTS: According to the ROC curve, the threshold value of LMR for 2 years PFS (%) of PGI-DLBCL patients was 2.6. Unvariate analysis showed that LMR (P＜0.05), large enclosed mass lesion (P＜0.01) and IPI (P＜0.05) were prognostic factors affecting PFS, the COX regression model multivariate analysis showed that LMR＜2.6 [ (risk ratio (RR)=3.083, 95%CI 1.828-8.313, P＜0.01], and large enclosed mass lesions (RR=2.718, 95%CI 1.339-6.424, P＜0.05) were the independent adverse prognostic factor for two years PFS. CONCLUSION: Both LMR＜2.6 and large enclosed mass lesions relate with the progress of PGI-DLBCL.

[Multivariate Analysis of Factors Influencing Recovery from Hemorrhagic Cystitis after Allo-HSCT].

OBJECTIVE: To analyze the incidence of hemorrhagic cystitis (HC) after allogeneic hematopoietic stem cell transplantation and the factors affecting HC, so as to provide clinical evidence for further treatment of HC. METHODS: The HC of 113 patients after allogeneic hematopoietic stem cell transplantation in Affiliated Hospital of Xuzhou Medical University between the years 2014-2016 was analyzed respectively. All cases of HC were divided into HC group and non-HC(control) group. The follow-up time: from preeonditionig day to 180 d after transplantation. The 10 clinical parameters were selected for univariate analysis with COX regression analysis: sex, age (＜25 years and 25 years), primary disease, conditioning regimen with anti-thymoglobulin(ATG), sex-mismatch in recipients, haploidential HSCT, cytomegalovirus (CMV) viremia, EB viremia, graft-versus-host disease (GVHD), and primary disease relapse, the factors significant at the 0.1 level in univariate analysis should be further evaluated by multivariate analysis using a COX regression analysis. The difference was significant at P＜0.05 in multivariate analysis. RESULTS: The HC occured in 31 of 113 patients (27.4%), with 5 cases of grade I (5.5%), 19 of grade II (16.8%), 5 of grade III (4.4%), and 2 of grade IV (1.8%). The median time of HC onset was 37 days (26-70 d) after transplantation. The median duration of HC was 14 days (5-55d). Univariate analysis showed that conditioning with anti-thymoglobulin (ATG) (RR=6.170, 95%CI: 1.875-20.306, P＜0.01), CMV viremia (RR=7.633, 95%CI：2.318-25.133) (P＜0.01), haploidentical HSCT (RR=0.307, 95%CI：0.137-0.686, P＜0.01), GVHD (RR=1.891, 95%CI：0.918-3.898, P＞0.05) were the risk factors for recovery from HC. The multivatiate analysis of above-mentioned risk factors with statistical significance showed that only CMV viremia (RR=4.770, 95%CI: 1.394-16.326, P＜0.05) was the indentified risk factor affecting the recovery from HC. CONCLUSION: Monitoring CMV viremia and antivirotic treatment are effective measurs to prevent the occurrence of HC and promote the recovery from HC.

Efficacy and safety of Hou Gu Mi Xi in patients with spleen qi deficiency syndrome who underwent radical gastrectomy for gastric cancer: protocol for a multicenter, randomized, double-blind, placebo-controlled trial.

BACKGROUND: Spleen qi deficiency (SQD), a syndrome based on traditional Chinese medicine (TCM) theory, is common in patients after radical gastrectomy. SQD manifests with chronic gastrointestinal disorders and systemic symptoms and is challenging to manage. Hou Gu Mi Xi (HGMX) is a dietary TCM formula for SQD. This study aims to evaluate the efficacy and safety of HGMX in patients with SQD who have undergone radical gastrectomy for gastric cancer. METHODS AND DESIGN: This study is a multicenter, randomized, double-blind, placebo-controlled trial. One hundred thirty patients with SQD who have undergone radical gastrectomy for gastric cancer will be assigned to receive either HGMX or placebo for 2 years. The main outcome will be changes in SQD symptoms assessed by the Spleen Qi Deficiency Symptoms Grading and Quantifying Scale. The secondary outcomes will be changes in quality of life assessed by the Short Form 36 scale, performance status as assessed by the Eastern Cooperative Oncology Group Performance Status scale, body weight, and body mass index. Progression-free survival will also be assessed as a secondary outcome. Adverse events (AEs), severe AEs, and study withdrawal due to AEs will be recorded to evaluate the safety of HGMX. DISCUSSION: The results of this trial will provide initial evidence for the use of HGMX as an alternative and complementary intervention to manage chronic postoperative complications in patients who have undergone radical gastrectomy for gastric cancer. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03025152 . Registered on 17 January 2017.

New Roles for Photoexcited Eosin†Y in Photochemical Reactions.

Neutral eosin Y-derived photoexcited states have been found to serve as photoacids and direct hydrogen atom transfer (HAT) catalysts in the activation of glycals and C-H bonds, respectively. These studies pave the way for further use of eosin Y in photochemical synthesis.

Eosin Y as a Redox Catalyst and Photosensitizer for Sequential Benzylic C-H Amination and Oxidation.

A new synergistic multicatalytic activation mode of eosin Y has been discovered by exploiting the redox potential of its ground state and excited state. This catalytic strategy proves to be an enabling tool for visible-light-driven sequential benzylic C-H amination and oxidation of o-benzyl-N-methoxyl-benzamides when using Selectfluor as a hydrogen atom transfer (HAT) reagent and O2 as oxidant. Efficient synthesis of a range of diversely functionalized 3-hydroxyisoindolinones can thus be achieved with good yields and selectivity at mild reaction conditions. Preliminary mechanistic studies and DFT calculations suggest that eosin Y works as a redox catalyst and photosensitizer.

Synthesis of Dihydropyrazoles via Ligand-Free Pd-Catalyzed Alkene Aminoarylation of Unsaturated Hydrazones with Diaryliodonium Salts.

A ligand-free, palladium-catalyzed aminoarylation reaction of the unactivated alkenes in ß,γ-unsaturated hydrazones is described. This protocol enables efficient and simultaneous formation of C(sp3)-N and C(sp3)-C(sp2) bonds under mild conditions, providing a practical and general approach to various diversely substituted dihydropyrazoles in generally good yields, without the use of any stoichiometric external oxidant.

Metabolic profiling of dehydrodiisoeugenol using xenobiotic metabolomics.

Dehydrodiisoeugenol (DDIE), a representative and major benzofuran-type neolignan in Myristica fragrans Houtt., shows anti-inflammatory and anti-bacterial actions. In order to better understand its pharmacological properties, xenobiotic metabolomics was used to determine the metabolic map of DDIE and its influence on endogenous metabolites. Total thirteen metabolites of DDIE were identified through in vivo and in vitro metabolism, and seven of them were reported for the first time in the present study. The identity of DDIE metabolites was achieved by comparison of the MS/MS fragmentation pattern with DDIE using ultra-performance chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-ESI- QTOFMS). Demethylation and ring-opening reaction were the major metabolic pathways for in vivo metabolism of DDIE. Recombinant cytochrome P450s (CYPs) screening revealed that CYP1A1 is a primary enzyme contributing to the formation of metabolites D1-D4. More importantly, the levels of two endogenous metabolites 2,8-dihydroxyquinoline and its glucuronide were significantly elevated in mouse urine after DDIE exposure, which explains in part its modulatory effects on gut microbiota. Taken together, these data contribute to the understanding of the disposition and pharmacological activities of DDIE in vivo.