An engineered Escherichia coli Nissle strain prevents lethal liver injury in a mouse model of tyrosinemia type 1.

BACKGROUND & AIMS: Hereditary tyrosinemia type 1 (HT1) results from the loss of fumarylacetoacetate hydrolase (FAH) activity and can lead to lethal liver injury. Therapeutic options for HT1 remain limited. In this study, we aimed to construct an engineered bacterium capable of reprogramming host metabolism and thereby provide a potential alternative approach for the treatment of HT1. METHODS: Escherichia coli Nissle 1917 (EcN) was engineered to express genes involved in tyrosine metabolism in the anoxic conditions that are characteristic of the intestine (EcN-HT). Bodyweight, survival rate, plasma (tyrosine/liver function), H&E staining and RNA sequencing were used to assess its ability to degrade tyrosine and protect against lethal liver injury in Fah-knockout (KO) mice, a well-accepted model of HT1. RESULTS: EcN-HT consumed tyrosine and produced L-DOPA (levodopa) in an in vitro system. Importantly, in Fah-KO mice, the oral administration of EcN-HT enhanced tyrosine degradation, reduced the accumulation of toxic metabolites, and protected against lethal liver injury. RNA sequencing analysis revealed that EcN-HT rescued the global gene expression pattern in the livers of Fah-KO mice, particularly of genes involved in metabolic signaling and liver homeostasis. Moreover, EcN-HT treatment was found to be safe and well-tolerated in the mouse intestine. CONCLUSIONS: This is the first report of an engineered live bacterium that can degrade tyrosine and alleviate lethal liver injury in mice with HT1. EcN-HT represents a novel engineered probiotic with the potential to treat this condition. IMPACT AND IMPLICATIONS: Patients with hereditary tyrosinemia type 1 (HT1) are characterized by an inability to metabolize tyrosine normally and suffer from liver failure, renal dysfunction, neurological impairments, and cancer. Given the overlap and complementarity between the host and microbial metabolic pathways, the gut microbiome provides a potential chance to regulate host metabolism through degradation of tyrosine and reduction of byproducts that might be toxic. Herein, we demonstrated that an engineered live bacterium, EcN-HT, could enhance tyrosine breakdown, reduce the accumulation of toxic tyrosine byproducts, and protect against lethal liver injury in Fah-knockout mice. These findings suggested that engineered live biotherapeutics that can degrade tyrosine in the gut may represent a viable and safe strategy for the prevention of lethal liver injury in HT1 as well as the mitigation of its associated pathologies.

Vacancy Engineering in 2D Transition Metal Chalcogenide Photocatalyst: Structure Modulation, Function and Synergy Application.

Transition metal chalcogenides (TMCs) are widely used in photocatalytic fields such as hydrogen evolution, nitrogen fixation, and pollutant degradation due to their suitable bandgaps, tunable electronic and optical properties, and strong reducing ability. The unique 2D malleability structure provides a pre-designed platform for customizable structures. The introduction of vacancy engineering makes up for the shortcomings of photocorrosion and limited light response and provides the greatest support for TMCs in terms of kinetics and thermodynamics in photocatalysis. This work reviews the effect of vacancy engineering on photocatalytic performance based on 2D semiconductor TMCs. The characteristics of vacancy introduction strategies are summarized, and the development of photocatalysis of vacancy engineering TMCs materials in energy conversion, degradation, and biological applications is reviewed. The contribution of vacancies in the optical range and charge transfer kinetics is also discussed from the perspective of structure manipulation. Vacancy engineering not only controls and optimizes the structure of the TMCs, but also improves the optical properties, charge transfer, and surface properties. The synergies between TMCs vacancy engineering and atomic doping, other vacancies, and heterojunction composite techniques are discussed in detail, followed by a summary of current trends and potential for expansion.

Rational design of waste anode graphite-derived carbon catalyst to activate peroxymonosulfate for atrazine degradation.

As the rapidly growing number of waste lithium-ion batteries (LIBs), the recycling and reutilization of anode graphite is of increasing interest. Converting waste anode graphite into functional materials may be a sensible option. Herein, a series of carbonaceous catalysts (TG) were successfully prepared using spent anode graphite calcined at various temperatures and applied for activating peroxymonosulfate (PMS) to degrade atrazine (ATZ). The catalyst obtained at 800 °C (TG-800) showed the optimum performance for ATZ removal (99.2% in 6 min). Various experimental conditions were explored to achieve the optimum efficiency of the system. In the TG-800/PMS system, free radicals (e.g., SO4·-, HO·), singlet oxygen (1O2), together with a direct electron transfer pathway all participated in ATZ degradation, and the ketonic (CO) group was proved as the leading catalytic site for PMS activation. The potential degradation routes of ATZ have also been presented. According to the toxicity assessment experiments, the toxicity of the intermediate products decreased. The reusability and universal applicability of the TG-800 were also confirmed. This research not only provides an efficient PMS activator for pollutant degradation, but also offers a meaningful reference for the recovery of waste anode graphite to develop environmentally functional materials.

Evaluation of the effects of three different processing methods of aconite on rat metabolites based on high-coverage pseudotargeted metabolomics.

Aconite is the processed product of the seed root of Aconitum carmichaelii Debx. Aconite is a commonly used traditional Chinese medicine, which is generally used after processing. Black aconite, light aconite, and salted aconite are three different processed aconite products. They have the effects of restoring yang and saving energy enemy, dispersing cold, and relieving pain. However, clinical aconite poisoning cases have frequently been reported. In our study, we investigated the effects of three different processed aconite products on the changes of metabolites in vivo. A total of 42 rats were randomly divided into seven groups with six rats in each group. After three consecutive days of intragastric administration of 2.7 g/kg of the aconite-processed product, rat serums were obtained. The rat metabolites were detected using liquid chromatography-tandem mass spectrometry. The altered metabolites related to aconite-processed products were discovered by statistical analysis using metaboanalyst software. Our study is the first time to comprehensively evaluate the effects of three different processed aconite products on rat metabolites based on pseudotargeted metabolomics.

Expert-based narrative review on contemporary use of an off-the-shelf multibranched endograft for endovascular treatment of thoracoabdominal aortic aneurysms: device design, anatomical suitability, technical tips, peri-operative care, clinical applications, and real-world experience.

Advanced endovascular techniques, such as fenestrated stent grafts, are nowadays available that permit minimally invasive treatment of complex abdominal aortic aneurysms. However, thoracoabdominal aortic aneurysm (TAAA) patients have anatomic limitations to fenestrated stent-grafts, given a large lumen, i.e. the gap between the endograft and the inner aortic wall. This has led to the development of branched endovascular aneurysm repair (BEVAR) as the ideal option for such patients. The Zenith t-Branch multibranched endograft (Cook Medical, Bloomington, Ind), which has been commercially available in Europe to treat TAAA since June 2012, represents a feasible off-the-shelf (OTS) alternative for treatment of such pathologies, especially in the urgent setting, for patients who cannot wait the time required for manufacturing and delivery of custom-made endografts. The device's anatomical suitability should be considered, especially for female patients with smaller iliofemoral vessels. Several tips may help deal with particularly complex scenarios (such as, for instance, in case of narrow inner aortic lumens or when treating patients with failure of prior EVAR), and a broad array of techniques and devices must be available to ensure technical and clinical success. Despite promising early outcomes, concerns remain particularly regarding the risk for spinal cord ischemia and further assessment of long-term durability is needed, including the rate of target vessel instability and need for secondary interventions. As the published evidence mainly comes from retrospective registries, it is likely that reported outcomes may suffer from an intrinsic bias as most procedures reported to date have been caried out at high-volume aortic centers. Nonetheless, with the never-ceasing adoption of new and refined techniques, outcomes are expected to ameliorate.

Sertraline Is an Effective SARS-CoV-2 Entry Inhibitor Targeting the Spike Protein.

The global spread of the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the continuously emerging new variants underscore an urgent need for effective therapeutics for the treatment of coronavirus disease 2019 (COVID-19). Here, we screened several FDA-approved amphiphilic drugs and determined that sertraline (SRT) exhibits potent antiviral activity against infection of SARS-CoV-2 pseudovirus (PsV) and authentic virus in vitro. It effectively inhibits SARS-CoV-2 spike (S)-mediated cell-cell fusion. SRT targets the early stage of viral entry. It can bind to the S1 subunit of the S protein, especially the receptor binding domain (RBD), thus blocking S-hACE2 interaction and interfering with the proteolysis process of S protein. SRT is also effective against infection with SARS-CoV-2 PsV variants, including the newly emerging Omicron. The combination of SRT and other antivirals exhibits a strong synergistic effect against infection of SARS-CoV-2 PsV. The antiviral activity of SRT is independent of serotonin transporter expression. Moreover, SRT effectively inhibits infection of SARS-CoV-2 PsV and alleviates the inflammation process and lung pathological alterations in transduced mice in vivo. Therefore, SRT shows promise as a treatment option for COVID-19. IMPORTANCE The study shows SRT is an effective entry inhibitor against infection of SARS-CoV-2, which is currently prevalent globally. SRT targets the S protein of SARS-CoV-2 and is effective against a panel of SARS-CoV-2 variants. It also could be used in combination to prevent SARS-CoV-2 infection. More importantly, with long history of clinical use and proven safety, SRT might be particularly suitable to treat infection of SARS-CoV-2 in the central nervous system and optimized for treatment in older people, pregnant women, and COVID-19 patients with heart complications, which are associated with severity and mortality of COVID-19.

Effectiveness of Pentavalent Rotavirus Vaccine in Shanghai, China: A Test-Negative Design Study.

OBJECTIVE: To evaluate vaccine effectiveness (VE) of a live oral pentavalent rotavirus vaccine (RotaTeq, RV5) among young children in Shanghai, China, via a test-negative design study. STUDY DESIGN: We consecutively recruited children visiting a tertiary children's hospital for acute diarrhea from November 2021 to February 2022. Information on clinical data and rotavirus vaccination was collected. Fresh fecal samples were obtained for rotavirus detection and genotyping. To evaluate VE of RV5 against rotavirus gastroenteritis among young children, unconditional logistic regression models were conducted to compare ORs for vaccination between rotavirus-positive cases and test-negative controls. RESULTS: A total of 390 eligible children with acute diarrhea were enrolled, including 45 (11.54%) rotavirus-positive cases and 345 (88.46%) test-negative controls. After excluding 4 cases (8.89%) and 55 controls (15.94%) who had received the Lanzhou lamb rotavirus vaccine, 41 cases (12.39%) and 290 controls (87.61%) were included for the evaluation of RV5 VE. After adjustment for potential confounders, the 3-dose RV5 vaccination showed 85% (95% CI, 50%-95%) VE against mild to moderate rotavirus gastroenteritis among children aged 14 weeks to ≤4 years and 97% (95% CI, 83%-100%) VE among children aged 14 weeks to ≤2 years with genotypes G8P8, G9P8, and G2P4 represented 78.95%, 18.42%, and 2.63% of circulation strains, respectively. CONCLUSIONS: A 3-dose vaccination of RV5 is highly protective against rotavirus gastroenteritis among young children in Shanghai. The G8P8 genotype prevailled in Shanghai after RV5 introduction.

Virus Infection and mRNA Nuclear Export.

Gene expression in eukaryotes begins with transcription in the nucleus, followed by the synthesis of messenger RNA (mRNA), which is then exported to the cytoplasm for its translation into proteins. Along with transcription and translation, mRNA export through the nuclear pore complex (NPC) is an essential regulatory step in eukaryotic gene expression. Multiple factors regulate mRNA export and hence gene expression. Interestingly, proteins from certain types of viruses interact with these factors in infected cells, and such an interaction interferes with the mRNA export of the host cell in favor of viral RNA export. Thus, these viruses hijack the host mRNA nuclear export mechanism, leading to a reduction in host gene expression and the downregulation of immune/antiviral responses. On the other hand, the viral mRNAs successfully evade the host surveillance system and are efficiently exported from the nucleus to the cytoplasm for translation, which enables the continuation of the virus life cycle. Here, we present this review to summarize the mechanisms by which viruses suppress host mRNA nuclear export during infection, as well as the key strategies that viruses use to facilitate their mRNA nuclear export. These studies have revealed new potential antivirals that may be used to inhibit viral mRNA transport and enhance host mRNA nuclear export, thereby promoting host gene expression and immune responses.

UdgX-Mediated Uracil Sequencing at Single-Nucleotide Resolution.

As an aberrant base in DNA, uracil is generated by either deoxyuridine (dU) misincorporation or cytosine deamination, and involved in multiple physiological and pathological processes. Genome-wide profiles of uracil are important for study of these processes. Current methods for whole-genome mapping of uracil all rely on uracil-DNA N-glycosylase (UNG) and are limited in resolution, specificity, and/or sensitivity. Here, we developed a UdgX cross-linking and polymerase stalling sequencing ("Ucaps-seq") method to detect dU at single-nucleotide resolution. First, the specificity of Ucaps-seq was confirmed on synthetic DNA. Then the effectiveness of the approach was verified on two genomes from different sources. Ucaps-seq not only identified the enrichment of dU at dT sites in pemetrexed-treated cancer cells with globally elevated uracil but also detected dU at dC sites within the "WRC" motif in activated B cells which have increased dU in specific regions. Finally, Ucaps-seq was utilized to detect dU introduced by the cytosine base editor (nCas9-APOBEC) and identified a novel off-target site in cellular context. In conclusion, Ucaps-seq is a powerful tool with many potential applications, especially in evaluation of base editing fidelity.

CDER167, a dual inhibitor of URAT1 and GLUT9, is a novel and potent uricosuric candidate for the treatment of hyperuricemia.

Urate transporter 1 (URAT1) and glucose transporter 9 (GLUT9) are important targets for the development of uric acid-lowering drugs. We previously showed that the flexible linkers of URAT1 inhibitors could enhance their potency. In this study we designed and synthesized CDER167, a novel RDEA3710 analogue, by introducing a linker (methylene) between the naphthalene and pyridine rings to increase flexibility, and characterized its pharmacological and pharmacokinetics properties in vitro and in vivo. We showed that CDER167 exerted dual-target inhibitory effects on both URAT1 and GLUT9: CDER167 concentration-dependently inhibited the uptake of [14C]-uric acid in URAT1-expressing HEK293 cells with an IC50 value of 2.08 ± 0.31 µM, which was similar to that of RDEA3170 (its IC50 value was 1.47 ± 0.23 µM). Using site-directed mutagenesis, we demonstrated that CDER167 might interact with URAT1 at S35 and F365. In GLUT9-expressing HEK293T cells, CDER167 concentration-dependently inhibited GLUT9 with an IC50 value of 91.55 ± 15.28 µM, whereas RDEA3170 at 100 µM had no effect on GLUT9. In potassium oxonate-induced hyperuricemic mice, oral administration of CDER167 (10 mg·kg-1 · d-1) for 7 days was more effective in lowering uric acid in blood and significantly promoted uric acid excretion in urine as compared with RDEA3170 (20 mg·kg-1 · d-1) administered. The animal experiment proved the safety of CDER167. In addition, CDER167 displayed better bioavailability than RDEA3170, better metabolic stability and no hERG toxicity at 100 µM. These results suggest that CDER167 deserves further investigation as a candidate antihyperuricemic drug targeting URAT1 and GLUT9.

Identification of potential metabolic biomarkers of polycystic ovary syndrome in follicular fluid by SWATH mass spectrometry.

BACKGROUND: Polycystic ovary syndrome (PCOS) is a complex disorder associated with multiple metabolic disturbance, including defective glucose metabolism and insulin resistance. The altered metabolites caused by the related metabolic disturbance may affect ovarian follicles, which can be reflected in follicular fluid composition. The aim of this study is to investigate follicular fluid metabolic profiles in women with PCOS using an advanced sequential window acquisition of all theoretical fragment-ion spectra (SWATH) mass spectrometry. MATERIALS AND METHODS: Nineteen women with PCOS and twenty-one healthy controls undergoing IVF/ET were recruited, and their follicular fluid samples were collected for metabolomic study. Follicular fluid metabolic profiles, including steroid hormones, free fatty acids, bioactive lipids, and amino acids were analyzed using the principal component analysis (PCA) and partial least squares to latent structure-discriminant analysis (PLS-DA) model. RESULTS: Levels of free fatty acids, 3-hydroxynonanoyl carnitine and eicosapentaenoic acid were significantly increased (P < 0.05), whereas those of bioactive lipids, lysophosphatidylcholines (LysoPC) (16:0), phytosphingosine, LysoPC (14:0) and LysoPC (18:0) were significantly decreased in women with PCOS (P < 0.05). Additionally, levels of steroid hormone deoxycorticosterone and two amino acids, phenylalanine and leucine were higher in the PCOS patients (P < 0.05). CONCLUSION: Women with PCOS display unique metabolic profiles in their follicular fluid, and this data may provide us with important biochemical information and metabolic signatures that enable a better understanding of the pathogenesis of PCOS.

Evaluation of the BioFire FilmArray Gastrointestinal Panel and Real-Time Polymerase Chain Reaction Assays for the Detection of Major Diarrheagenic Pathogens by a Multicenter Diarrheal Disease Surveillance Program in China.

In the field of the detection of pathogens responsible for infectious diarrhea, multiplex nucleic acids detection technology has attracted attention due to its ability to simultaneously screen a wide range of pathogens, its simplicity to operate and a faster turnaround time. We conducted a three-center evaluation that compared the BioFire FilmArray gastrointestinal panel (FA GI) and real-time polymerase chain reaction (PCR) assays for the detection of pathogens from 462 clinical diarrhea specimens, and characterized the distribution of various pathogens that were analyzed. The sensitivity of FA GI was 100% for 13 pathogens and 93.8-98.3% for 4 pathogens, but low for Salmonella (60.5%) and adenovirus (88.9%). The sensitivity per pathogen of real-time PCR assays was lower than that observed with FA GI. The specificity of FA GI and real-time PCR assays per pathogen was greater than 94.5% and 99%, respectively. FA GI and real-time PCR assays detected ≥1 pathogen in 339 (73.4%) and 297 (64.3%) samples, respectively, and 324 (70.1%) samples were considered as positive according to the reference standard. Multiple pathogens were detected in 37.2% and 24.9% of samples by FA GI and real-time PCR assays, respectively. Norovirus GI/GII and Campylobacter were less associated with coinfections. The positive rates of some pathogens varied among the three regions of China. Molecular methods can help squickly identify the cause of diarrhea and provide valuable information for early diagnosis and optimal patient therapy.

Melatonin protects mouse spermatogonial stem cells against hexavalent chromium-induced apoptosis and epigenetic histone modification.

Given the potential biological functions of spermatogonial stem cells (SSCs) in spermatogenesis and in delivering parental genetic information to the next generation, how these cells respond to environmental toxins and carcinogens should be investigated. We examined the toxic effect of hexavalent chromium (Cr(VI)) on global histone modifications and apoptotic signaling pathways in SSCs. We determined the effect of melatonin, one of the most powerful endogenous free radical scavengers and wide-spectrum antioxidants, in protecting SSCs from Cr(VI)-induced apoptosis and global histone modification by Western blot analysis. In addition, we examined the in vivo effect of melatonin on Cr(VI)-induced histological changes of seminiferous tubules in mouse testes. We also evaluated the fertility of male mice by monitoring litter size following intraperitoneal injection of these chemicals. Our study demonstrated the Cr(VI)-induced global increases in H3K9me3 and H3K27me3 and activated the apoptotic signaling pathway. Pretreatment of SSCs with melatonin alleviated Cr(VI)-induced apoptosis and the global increase of H3K9me3. Exposure to melatonin also attenuated the Cr(VI)-induced increase of the abundance of histone methyltransferase ESET. Furthermore, exogenous administration of melatonin protected mice against Cr(VI)-induced changes in testicular histology and germ cell apoptosis, which helped maintain normal spermatogenesis and male fertility. Our study revealed a potential new therapeutic approach for male reproductive injury caused by Cr(VI).

Profiling of miRNAs in porcine germ cells during spermatogenesis.

Spermatogenesis includes mitosis of spermatogonia, meiosis of pachytene spermatocytes and spermiogenesis of round spermatids. MiRNAs as a ~22 nt small noncoding RNA are involved in regulating spermatogenesis at post-transcriptional level. However, the dynamic miRNAs expression in the developmental porcine male germ cells remains largely undefined. In this study, we purified porcine spermatogonia, pachytene spermatocytes and round spermatids using a STA-PUT apparatus. A small RNA deep sequencing and analysis were conducted to establish a miRNAs profiling in these male germ cells. We found that 19 miRNAs were differentially expressed between spermatogonia and pachytene spermatocytes, and 74 miRNAs differentially expressed between pachytene spermatocytes and round spermatids. Furthermore, 91 miRNAs were upregulated, while 108 miRNAs were downregulated in spermatozoa. We demonstrated that ssc-miR-10a-5p, ssc-miR-125b, ssc-let-7f and ssc-miR-186 were highly expressed in spermatogonia, pachytene spermatocytes, round spermatids and spermatozoa respectively. The findings could provide novel insights into roles of miRNAs in regulation of porcine spermatogenesis.

Aggregation behavior of polystyrene nanoplastics: Role of surface functional groups and protein and electrolyte variation.

Aggregation kinetics of plastics are affected by the surface functional groups and exposure orders (electrolyte and protein) with kinds of mechanisms in aquatic environment. This study investigates the aggregation of polystyrene nanoplastics (PSNPs) with varying surface functional groups in the presence of common electrolytes (NaCl, CaCl2, Na2SO4) and bovine serum albumin (BSA). It also examines the impact of different exposure orders, namely BSA + NaCl (adding them together), BSA → NaCl (adding BSA firstly and then NaCl), and NaCl → BSA (adding NaCl firstly and then BSA), on PSNPs aggregation. The presence of BSA decreased the critical coagulation concentration in NaCl (CCCNa+) of the non-modified PS-Bare from 222.17 to 142.81 mM (35.72%), but increased that of the carboxyl-modified PS-COOH from 157.34 to 160.03 mM (1.71%). This might be ascribed to the thicker absorbed layer of BSA onto the PS-Bare surface, known from Ohshima's soft particle theory. Their aggregation in CaCl2 was both increased because of Ca2+ bridging. Different from the monotonous effects of BSA on PS-Bare and PS-COOH, BSA initially facilitated PS-NH2 aggregation via patch-charge attraction, then inhibited it at higher salt levels through steric repulsion. Furthermore, exposure orders had no significant effect on PS-Bare and PS-COOH, but had a NaCl concentration-dependent impact on PS-NH2. At the low NaCl concentrations (10 and 100 mM), no obvious influence could be observed. While, at 300 mM NaCl, the high concentrations of BSA could not totally stabilize the salt-induced aggregates in NaCl → BSA, but could achieve it in the other two orders. These might be attributed to the electrical double layer compression by NaCl, "patch-charge" force and steric hindrance by BSA. These experimental findings shed light on the potential fate and transport of nanoparticles in aquatic environments.

The nuclear localization signal of monkeypox virus protein P2 orthologue is critical for inhibition of IRF3-mediated innate immunity.

The Orthopoxvirus (OPXV) genus of the Poxviridae includes human pathogens variola virus (VARV), monkeypox virus (MPXV), vaccinia virus (VACV), and a number of zoonotic viruses. A number of Bcl-2-like proteins of VACV are involved in escaping the host innate immunity. However, little work has been devoted to the evolution and function of their orthologues in other OPXVs. Here, we found that MPXV protein P2, encoded by the P2L gene, and P2 orthologues from other OPXVs, such as VACV protein N2, localize to the nucleus and antagonize interferon (IFN) production. Exceptions to this were the truncated P2 orthologues in camelpox virus (CMLV) and taterapox virus (TATV) that lacked the nuclear localization signal (NLS). Mechanistically, the NLS of MPXV P2 interacted with karyopherin α-2 (KPNA2) to facilitate P2 nuclear translocation, and competitively inhibited KPNA2-mediated IRF3 nuclear translocation and downstream IFN production. Deletion of the NLS in P2 or orthologues significantly enhanced IRF3 nuclear translocation and innate immune responses, thereby reducing viral replication. Moreover, deletion of NLS from N2 in VACV attenuated viral replication and virulence in mice. These data demonstrate that the NLS-mediated translocation of P2 is critical for P2-induced inhibition of innate immunity. Our findings contribute to an in-depth understanding of the mechanisms of OPXV P2 orthologue in innate immune evasion.

Pregnane X receptor activation induces liver enlargement and regeneration and simultaneously promotes the metabolic activity of CYP3A1/2 and CYP2C6/11 in rats.

Human pregnane X receptor (PXR) is critical for regulating the expression of key drug-metabolizing enzymes such as CYP3A and CYP2C. Our recent study revealed that treatment with rodent-specific PXR agonist pregnenolone-16α-carbonitrile (PCN) significantly induced hepatomegaly and promoted liver regeneration after two-thirds partial hepatectomy (PHx) in mice. However, it remains unclear whether PXR activation induces hepatomegaly and liver regeneration and simultaneously promotes metabolic function of the liver. Here, we investigated the metabolism activity of CYP1A2, CYP3A1/2 and CYP2C6/11 during PXR activation-induced liver enlargement and regeneration in rats after cocktail dosing of CYP probe drugs. For PCN-induced hepatomegaly, a notable increase in the metabolic activity of CYP3A1/2 and CYP2C6/11, as evidenced by the plasma exposure of probe substrates and the AUC ratios of the characteristic metabolites to its corresponding probe substrates. The metabolic activity of CYP1A2, CYP3A1/2 and CYP2C6/11 decreased significantly after PHx. However, PCN treatment obviously enhanced the metabolic activity of CYP2C6/11 and CYP3A1/2 in PHx rats. Furthermore, the protein expression levels of CYP3A1/2 and CYP2C6/11 in liver were up-regulated. Taken together, this study demonstrates that PXR activation not only induces hepatomegaly and liver regeneration in rats, but also promotes the protein expression and metabolic activity of the PXR downstream metabolizing enzymes such as CYP3A1/2 and CYP2C6/11 in the body.

Systematic tracking of nitrogen sources in complex river catchments: Machine learning approach based on microbial metagenomics.

Tracking nitrogen pollution sources is crucial for the effective management of water quality; however, it is a challenging task due to the complex contaminative scenarios in the freshwater systems. The contaminative pattern variations can induce quick responses of aquatic microorganisms, making them sensitive indicators of pollution origins. In this study, the soil and water assessment tool, accompanied by a detailed pollution source database, was used to detect the main nitrogen pollution sources in each sub-basin of the Liuyang River watershed. Thus, each sub-basin was assigned to a known class according to SWAT outputs, including point source pollution-dominated area, crop cultivation pollution-dominated area, and the septic tank pollution-dominated area. Based on these outputs, the random forest (RF) model was developed to predict the main pollution sources from different river ecosystems using a series of input variable groups (e.g., natural macroscopic characteristics, river physicochemical properties, 16S rRNA microbial taxonomic composition, microbial metagenomic data containing taxonomic and functional information, and their combination). The accuracy and the Kappa coefficient were used as the performance metrics for the RF model. Compared with the prediction performance among all the input variable groups, the prediction performance of the RF model was significantly improved using metagenomic indices as inputs. Among the metagenomic data-based models, the combination of the taxonomic information with functional information of all the species achieved the highest accuracy (0.84) and increased median Kappa coefficient (0.70). Feature importance analysis was used to identify key features that could serve as indicators for sudden pollution accidents and contribute to the overall function of the river system. The bacteria Rhabdochromatium marinum, Frankia, Actinomycetia, and Competibacteraceae were the most important species, whose mean decrease Gini indices were 0.0023, 0.0021, 0.0019, and 0.0018, respectively, although their relative abundances ranged only from 0.0004 to 0.1 %. Among the top 30 important variables, functional variables constituted more than half, demonstrating the remarkable variation in the microbial functions among sites with distinct pollution sources and the key role of functionality in predicting pollution sources. Many functional indicators related to the metabolism of Mycobacterium tuberculosis, such as K24693, K25621, K16048, and K14952, emerged as significant important factors in distinguishing nitrogen pollution origins. With the shortage of pollution source data in developing regions, this suggested approach offers an economical, quick, and accurate solution to locate the origins of water nitrogen pollution using the metagenomic data of microbial communities.

Metabolism characterization and toxicity of N-hydap, a marine candidate drug for lung cancer therapy by LC-MS method.

N-Hydroxyapiosporamide (N-hydap), a marine product derived from a sponge-associated fungus, has shown promising inhibitory effects on small cell lung cancer (SCLC). However, there is limited understanding of its metabolic pathways and characteristics. This study explored the in vitro metabolic profiles of N-hydap in human recombinant cytochrome P450s (CYPs) and UDP-glucuronosyltransferases (UGTs), as well as human/rat/mice microsomes, and also the pharmacokinetic properties by HPLC-MS/MS. Additionally, the cocktail probe method was used to investigate the potential to create drug-drug interactions (DDIs). N-Hydap was metabolically unstable in various microsomes after 1 h, with about 50% and 70% of it being eliminated by CYPs and UGTs, respectively. UGT1A3 was the main enzyme involved in glucuronidation (over 80%), making glucuronide the primary metabolite. Despite low bioavailability (0.024%), N-hydap exhibited a higher distribution in the lungs (26.26%), accounting for its efficacy against SCLC. Administering N-hydap to mice at normal doses via gavage did not result in significant toxicity. Furthermore, N-hydap was found to affect the catalytic activity of drug metabolic enzymes (DMEs), particularly increasing the activity of UGT1A3, suggesting potential for DDIs. Understanding the metabolic pathways and properties of N-hydap should improve our knowledge of its drug efficacy, toxicity, and potential for DDIs.