Enlargement of the knowledge of Cortinarius section Anomali (Agaricales, Basidiomycota): introducing three new species from China.

Cortinarius is a globally distributed agaricoid genus that has been well studied in Europe and America with over 1,000 described species. However, as part of an ongoing effort to investigate the diversity of Cortinarius section Anomali in China, the resource investigation and classification research are still limited, and the species diversity has not been clarified by far. During the re-examination of the Chinese Cortinarius specimens, C. cinnamomeolilacinus, C. subclackamasensis, and C. tropicus, belonging to the sect. Anomali, were described in China as new to science based on morphological examination and phylogenetic analysis. The three new species are described and illustrated in detail according to the Chinese materials. The phylogenetic analysis based on internal transcribed spacer sequences confirmed the placement of the three species in the Cortinarius sect. Anomali clade. Phylogenetically related and morphologically similar species to these three new species are discussed.

Morphology and phylogeny identify two new species and one new subspecies of Podoscypha from Yunnan Province, Southwest China.

In this study, Podoscypha was taxonomically and phylogenetically evaluated. In total, five specimens collected from the tropical areas of Yunnan Province in Southwest China were studied. In combination with morphological observations and phylogenetic analyses based on ITS and LSU loci, two new species and one new subspecies, Podoscypha subinvoluta, P. tropica, and P. petalodes subsp. cystidiata, respectively, were discovered. The illustrated descriptions of the new species and subspecies are provided. Moreover, the main morphological differences between related species are discussed.

JMJ28 guides sequence-specific targeting of ATX1/2-containing COMPASS-like complex in Arabidopsis.

Despite extensive investigations in mammals and yeasts, the importance and specificity of COMPASS-like complex, which catalyzes histone 3 lysine 4 methylation (H3K4me), are not fully understood in plants. Here, we report that JMJ28, a Jumonji C domain-containing protein in Arabidopsis, recognizes specific DNA motifs through a plant-specific WRC domain and acts as an interacting factor to guide the chromatin targeting of ATX1/2-containing COMPASS-like complex. JMJ28 associates with COMPASS-like complex in vivo via direct interaction with RBL. The DNA-binding activity of JMJ28 is essential for both the targeting specificity of ATX1/2-COMPASS and the deposition of H3K4me at specific loci but exhibit functional redundancy with alternative COMPASS-like complexes at other loci. Finally, we demonstrate that JMJ28 is a negative regulator of plant immunity. In summary, our findings reveal a plant-specific recruitment mechanism of COMPASS-like complex. These findings help to gain deeper insights into the regulatory mechanism of COMPASS-like complex in plants.

A comprehensive review of BET-targeting PROTACs for cancer therapy.

Targeted protein degradation using proteolysis-targeting chimeras (PROTACs) has emerged as an effective strategy for drug discovery, given their unique advantages over target protein inhibition. The bromodomain and extra-terminal (BET) family proteins play a key role in regulating oncogene expression and are considered attractive therapeutic targets for cancer therapy. Considering the therapeutic potential of BET proteins in cancer and the marked attractiveness of PROTACs, BET-targeting PROTACs have been extensively pursued. Recently, BET-targeting PROTACs based on new E3 ligases and novel strategies, such as light-activated, macrocyclic, folate-caged, aptamer-PROTAC conjugation, antibody-coupling, and autophagy-targeting strategies, have emerged. In the present review, we provide a comprehensive summary of advances in BET-targeting PROTACs.

Toxin screening of Pseudosperma umbrinellum (Agaricals, Basidiomycota): First report of phalloidin in Inocybaceae mushroom.

Pseudosperma species are widely distributed worldwide. Many of them cause poisoning incidents every year, and the toxin responsible for poisoning is muscarine, which could stimulate the parasympathetic nervous system. This study established a method using multiwalled carbon nanotube purification and liquid chromatography-tandem mass spectrometry for the targeted screening of mushroom toxins (muscarine, isoxazole derivatives, tryptamine alkaloids, three amatoxins and three phallotoxins) from Pseudosperma umbrinellum, a common poisonous mushroom distributed in north and northwestern China. Surprisingly, in addition to muscarine, phalloidin was also detected in P. umbrinellum, and the contents were 3022.2 ± 604.4 to 4002.3 ± 804.6 mg/kg (k = 2; p = 95%) muscarine and 5.9 ± 1.2 to 9.3 ± 1.8 mg/kg (k = 2; p = 95%) phalloidin.

A New Muscarine-Containing Inosperma (Inocybaceae, Agaricales) Species Discovered From One Poisoning Incident Occurring in Tropical China.

Currently, mushroom poisoning still poses a huge problem to humans' health and life globally. Poisoning incidents caused by Inosperma spp. were reported continuously in tropical China in recent years. In this study, a new poisonous Inosperma species, discovered from a poisoning incident, was described in tropical China based on morphological, molecular, and toxin detection evidence; detailed descriptions, photographs, and comparisons to closely related species were provided. For qualitative analysis, through targeted screening using ultra-high liquid chromatography triple quadrupole mass spectrometry (UPLC-MS/MS), the new species contains muscarine and no other toxins (two isoxazole derivatives, two tryptamine alkaloids, three amatoxins, and three phallotoxins). For quantitative analysis, muscarine contents in the pileus and the stipe were 2.08 ± 0.05 and 6.53 ± 1.88 g/kg, respectively.

Recent strategies targeting Embryonic Ectoderm Development (EED) for cancer therapy: Allosteric inhibitors, PPI inhibitors, and PROTACs.

The polycomb repressive complex 2 (PRC2), which comprised of the core subunits: Enhancer of Zeste Homolog 2 (EZH2), Suppressor of Zeste 12 (SUZ12), and Embryonic Ectoderm Development (EED), is an essential epigenetic gene silencer responsible for depositing repressive histone H3 lysine 27 trimethylation (H3K27me3) marks on chromatin. The aberrant activity of PRC2 is closely involved in tumorigenesis and progression, making its inhibition a viable strategy for epigenetic cancer therapy. Although the clinical development of small PRC2 inhibitors has made impressive progress, with one EZH2 inhibitor approved for cancer therapy and several other candidates in clinical trials, current EZH2 inhibitors are limited to treating certain hematological malignancies and have acquired drug resistance. EED is essential for PRC2 stabilization and allosterically stimulating PRC2 activity because it functions as a scaffold protein and an H3K27me3-recognizing protein. Thus, due to its novel mechanism of action, targeting EED provides a promising new strategy for inhibiting PRC2 function and exhibits the potential to overcome the issues encountered by EZH2 inhibitors. This review provides a comprehensive overview of available cancer therapy strategies that target EED, including allosteric inhibitors, protein-protein interaction (PPI) inhibitors, and proteolysis-targeting chimeras (PROTACs).

 Pseudospermaarenarium (Inocybaceae), a new poisonous species from Eurasia, based on morphological, ecological, molecular and biochemical evidence.

In this study, Pseudospermaarenarium is proposed as a new species, based on morphological, ecological, molecular and biochemical evidence. The new species grows on sandy ground under Populus and Pinussylvestris in north-western China and northern Europe, respectively. It is characterised by the combination of the robust habit, nearly glabrous pileus, large cylindrical basidiospores, thin-walled cheilocystidia and ecological associations with Populusalba × P.berolinensis and Pinussylvestris and unique phylogenetic placement. Additionally, a comprehensive toxin determination of the new species using ultra-high performance liquid chromatography-tandem mass spectrometry was conducted. Results showed that it was a muscarine-positive species. The content were approximately five times higher in the pilei [4012.2 ± 803.1-4302.3 ± 863.2 mg/kg (k = 2, p = 95%)] than in the stipes [850.4 ± 171.1-929.1 ± 184.2 mg/kg (k = 2, p = 95%)], demonstrating the severity of mushroom poisoning when patients consumed different parts of the poisonous mushroom. Amatoxins, phallotoxins, ibotenic acid, muscimol, psilocybin and psilocin were not detected.

Buzhong Tiaogan Formula for delaying colorectal liver metastasis (liver depression spleen deficient type): A multicenter randomized controlled trial: A study protocol.

INTRODUCTION: Colorectal cancer has been ranked third among the most common cancers worldwide and raised to the second leading cause of cancer death with nearly one-tenth of cancer-related deaths globally, and nearly half of colorectal cancer patients present with or develop colorectal cancer liver metastasis (CRLM). Buzhong Tiaogan Formula (BTF) has been proven to treat CRLM in our team, but there are lacking of evidence on its effective in delaying colorectal liver metastasis (liver depression spleen deficiency type), so we will evaluate the efficacy and safety of BTF in preventing the occurrence of CRLM. METHODS: This randomized controlled trial (RCT) will be carried out in 3 different hospitals in Shanxi Province planning to recruit 150 CRLM patients with the type of liver depression spleen deficiency. The control group will be treated by basic antitumor therapy and the treatment group will use BTF plus basic antitumor therapy. The primary outcomes will be quality of life of included patients, the time of occurrence of liver metastasis, the score of traditional Chinese medicine symptom for the type of liver depression spleen deficiency; and the secondary outcomes will include overall survival, progression-free survival, DFS, tumor microenvironment and immune state of the included patient. Safety evaluation will be recorded during the whole study. All data in this RCT will be analyzed by SPSS 23.0 software. This study has been approved by the Clinical Research Ethics Committee of Shanxi Province Hospital of Traditional Chinese medicine (2021Y-06016). DISCUSSION: The results of this RCT will contribute to BTF for delaying colorectal liver metastasis (liver depression spleen deficient type). And the results from this RCT will be published in a relevant journal after finished. TRIAL REGISTRATION: ChiMCTR2100005268 (September 4, 2021).

Fusarium BP1 is a reader of H3K27 methylation.

Histone H3 lysine 27 methylation catalyzed by polycomb repressive complex 2 (PRC2) is conserved from fungi to humans and represses gene transcription. However, the mechanism for recognition of methylated H3K27 remains unclear, especially in fungi. Here, we found that the bromo-adjacent homology (BAH)-plant homeodomain (PHD) domain containing protein BAH-PHD protein 1 (BP1) is a reader of H3K27 methylation in the cereal fungal pathogen Fusarium graminearum. BP1 interacts with the core PRC2 component Suz12 and directly binds methylated H3K27. BP1 is distributed in a subset of genomic regions marked by H3K27me3 and co-represses gene transcription. The BP1 deletion mutant shows identical phenotypes on mycelial growth and virulence, as well as similar expression profiles of secondary metabolite genes to the strain lacking the H3K27 methyltransferase Kmt6. More importantly, BP1 can directly bind DNA through its PHD finger, which might increase nucleosome residence and subsequently reinforce transcriptional repression in H3K27me3-marked target regions. A phylogenetic analysis showed that BP1 orthologs are mainly conserved in fungi. Overall, our findings provide novel insights into the mechanism by which PRC2 mediates gene repression in fungi, which is distinct from the PRC1-PRC2 system in plants and mammals.

Genome-wide distribution and functions of the AAE complex in epigenetic regulation in Arabidopsis.

Heterochromatin is widespread in eukaryotic genomes and has diverse impacts depending on its genomic context. Previous studies have shown that a protein complex, the ASI1-AIPP1-EDM2 (AAE) complex, participates in polyadenylation regulation of several intronic heterochromatin-containing genes. However, the genome-wide functions of AAE are still unknown. Here, we show that the ASI1 and EDM2 mostly target the common genomic regions on a genome-wide level and preferentially interacts with genetic heterochromatin. Polyadenylation (poly(A) sequencing reveals that AAE complex has a substantial influence on poly(A) site usage of heterochromatin-containing genes, including not only intronic heterochromatin-containing genes but also the genes showing overlap with heterochromatin. Intriguingly, AAE is also involved in the alternative splicing regulation of a number of heterochromatin-overlapping genes, such as the disease resistance gene RPP4. We provided evidence that genic heterochromatin is indispensable for the recruitment of AAE in polyadenylation and splicing regulation. In addition to conferring RNA processing regulation at genic heterochromatin-containing genes, AAE also targets some transposable elements (TEs) outside of genes (including TEs sandwiched by genes and island TEs) for epigenetic silencing. Our results reveal new functions of AAE in RNA processing and epigenetic silencing, and thus represent important advances in epigenetic regulation.

Coupling of H3K27me3 recognition with transcriptional repression through the BAH-PHD-CPL2 complex in Arabidopsis.

Histone 3 Lys 27 trimethylation (H3K27me3)-mediated epigenetic silencing plays a critical role in multiple biological processes. However, the H3K27me3 recognition and transcriptional repression mechanisms are only partially understood. Here, we report a mechanism for H3K27me3 recognition and transcriptional repression. Our structural and biochemical data showed that the BAH domain protein AIPP3 and the PHD proteins AIPP2 and PAIPP2 cooperate to read H3K27me3 and unmodified H3K4 histone marks, respectively, in Arabidopsis. The BAH-PHD bivalent histone reader complex silences a substantial subset of H3K27me3-enriched loci, including a number of development and stress response-related genes such as the RNA silencing effector gene ARGONAUTE 5 (AGO5). We found that the BAH-PHD module associates with CPL2, a plant-specific Pol II carboxyl terminal domain (CTD) phosphatase, to form the BAH-PHD-CPL2 complex (BPC) for transcriptional repression. The BPC complex represses transcription through CPL2-mediated CTD dephosphorylation, thereby causing inhibition of Pol II release from the transcriptional start site. Our work reveals a mechanism coupling H3K27me3 recognition with transcriptional repression through the alteration of Pol II phosphorylation states, thereby contributing to our understanding of the mechanism of H3K27me3-dependent silencing.

The Crosstalk Between Epigenetic Mechanisms and Alternative RNA Processing Regulation.

As a co-transcriptional process, RNA processing, including alternative splicing and alternative polyadenylation, is crucial for the generation of multiple mRNA isoforms. RNA processing mechanisms are widespread across all higher eukaryotes and play critical roles in cell differentiation, organ development and disease response. Recently, significant progresses have been made in understanding the mechanism of RNA processing. RNA processing is regulated by trans-acting factors such as splicing factors, RNA-binding proteins and cis-sequences in pre-mRNA, and increasing evidence suggests that epigenetic mechanisms, which are important for the dynamic regulation and state of specific chromatic regions, are also involved in co-transcriptional RNA processing. In contrast, recent studies also suggest that alternative RNA processing also has a feedback regulation on epigenetic mechanisms. In this review, we discuss recent studies and summarize the current knowledge on the epigenetic regulation of alternative RNA processing. In addition, a feedback regulation of RNA processing on epigenetic regulators is also discussed.

Adenovirus infection promotes the formation of glioma stem cells from glioblastoma cells through the TLR9/NEAT1/STAT3 pathway.

BACKGROUND: Glioma stem cells (GSCs) are glioma cells with stemness and are responsible for a variety of malignant behaviors of glioma. Evidence has shown that signals from tumor microenvironment (TME) enhance stemness of glioma cells. However, identification of the signaling molecules and underlying mechanisms has not been completely elucidated. METHODS: Human samples and glioma cell lines were cultured in vitro to determine the effects of adenovirus (ADV) infection by sphere formation, RT-qPCR, western blotting, FACS and immunofluorescence. For in vivo analysis, mouse intracranial tumor model was applied. Bioinformatics analysis, gene knockdown by siRNA, RT-qPCR and western blotting were applied for further mechanistic studies. RESULTS: Infection of patient-derived glioma cells with ADV increases the formation of tumor spheres. ADV infection upregulated stem cell markers and in turn promoted the capacities of self-renewal and multi-lineage differentiation of the infected tumor spheres. These ADV infected tumor spheres had stronger potential to form xenograft tumors in immune-compromised mice. GSCs formation could be promoted by ADV infection via TLR9, because TLR9 was upregulated after ADV infection, and knockdown of TLR9 reduced ADV-induced GSCs. Consistently, MYD88, as well as total STAT3 and phosphorylated (p-)STAT3, were also upregulated in ADV-induced GSCs. Knockdown of MYD88 or pharmaceutical inhibition of STAT3 attenuated stemness of ADV-induced GSCs. Moreover, we found that ADV infection upregulated lncRNA NEAT1. Knockdown of NEAT1 impaired stemness of ADV-induced GSCs. Lastly, HMGB1, a damage associated molecular pattern (DAMP) that triggers TLR signaling, also upregulated stemness markers in glioma cells. CONCLUSION: ADV, which has been developed as vectors for gene therapy and oncolytic virus, promotes the formation of GSCs via TLR9/NEAT1/STAT3 signaling. Video abstract.

Bufalin-induced cardiotoxicity: new findings into mechanisms.

Bufalin is one of the main pharmacological and toxicological components of Venenum Bufonis and many traditional Chinese medicine preparations. The cardiotoxicity clearly limits its application to patients living in countries. Hence, an investigation of its toxicological mechanism is helpful for new drug development and treatment of the related clinical adverse reactions. We investigate the cardiotoxicity of bufalin using human induced pluripotent stem cells-derived cardiomyocytes (hiPSC-CMs) (0.003-0.1 µmol·L-1), human induced pluripotent stem cells-derived cardiomyocytes (hiPSC-CMs) (0.03-0.3 µmol·L-1) and eight human cardiac ion channel currents (0.01-100 µmol·L-1) combined with an impedance-based bioanalytical and patch clamp method. Biphasic effect of bufalin on the contractility in hiPSC-CMs, which has been shown to strengthen myocardial contractility, accelerate conduction, and increase beating rate at the earlier stage of administration, whereas weakened myocardial contractility, abolished conduction, and ceased beating rate at the later stage of administration. Bufalin decreased the action potential duration (Action potential duration at 30%, 50% and 90% repolarization), cardiac action potential amplitude, and maximal depolarization rate and depolarized the resting membrane potential of hiPSC-CMs. Spontaneous beating rates of hiPSC-CMs were markedly increased at 0.03 µmol·L-1, while were weakened at 0.3 µmol·L-1 after application. Bufalin blocks INav1.5 in a concentration-dependent manner with half maximal inhibitory concentration of 74.5 µmol·L-1. Bufalin respectively increased the late sodium current and Na+-Ca2+ exchange current with a concentration for 50% of maximal effect of 2.48 and 66.06 µmol·L-1 in hiPSC-CMs. Whereas, bufalin showed no significant effects on other cardiac ion channel currents. The enhancement of the late sodium current is one of the main mechanism for cardiotoxicity of bufalin.

Mushroom poisoning from Inocybe serotina: A case report from Ningxia, northwest China with exact species identification and muscarine detection.

Mushroom poisoning is a serious food safety issue in China. However, there is insufficient information on many poisoning incidents, including mushroom species and their clinical manifestations, diagnosis, treatments and toxins. Detailed epidemiological investigation was conducted after the occurrence of a mushroom poisoning incident resulting in typical muscarinic syndrome in Ningxia, China. The suspected mushroom species was identified based on morphological and phylogenetic analyses. Muscarine was detected using ultrahigh-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). On September 2, 2019, two patients exhibited typical muscarinic syndrome after consuming wild mushrooms. The clinical manifestations included chills, sweating, salivation and diarrhoea; the incubation period was approximately 2 h. Treatments, including anti-inflammatory, detoxification and nutritional support, were remedial. Full recovery ensued within 24 h. The specimen was identified as Inocybe serotina, and its muscarine content was 324.0 ± 62.4 mg/kg (k = 2, p = 95%). Two patients were poisoned via stimulation of their parasympathetic nervous system due to mistaken consumption of muscarine-containing I. serotina. They fully recovered with supportive treatments. To our knowledge, this is the first case report of I. serotina poisoning worldwide and is the first record of this species in China. Further, a method for muscarine detection was established using UPLC-MS/MS.

Neurons can upregulate Cav-1 to increase intake of endothelial cells-derived extracellular vesicles that attenuate apoptosis via miR-1290.

Extracellular vesicles (EVs) including exosomes can serve as mediators of cell-cell communication under physiological and pathological conditions. However, cargo molecules carried by EVs to exert their functions, as well as mechanisms for their regulated release and intake, have been poorly understood. In this study, we examined the effects of endothelial cells-derived EVs on neurons suffering from oxygen-glucose deprivation (OGD), which mimics neuronal ischemia-reperfusion injury in human diseases. In a human umbilical endothelial cell (HUVEC)-neuron coculture assay, we found that HUVECs reduced apoptosis of neurons under OGD, and this effect was compromised by GW4869, a blocker of exosome release. Purified EVs could be internalized by neurons and alleviate neuronal apoptosis under OGD. A miRNA, miR-1290, was highly enriched in HUVECs-derived EVs and was responsible for EV-mediated neuronal protection under OGD. Interestingly, we found that OGD enhanced intake of EVs by neurons cultured in vitro. We examined the expression of several potential receptors for EV intake and found that caveolin-1 (Cav-1) was upregulated in OGD-treated neurons and mice suffering from middle cerebral artery occlusion (MCAO). Knock-down of Cav-1 in neurons reduced EV intake, and canceled EV-mediated neuronal protection under OGD. HUVEC-derived EVs alleviated MCAO-induced neuronal apoptosis in vivo. These findings suggested that ischemia likely upregulates Cav-1 expression in neurons to increase EV intake, which protects neurons by attenuating apoptosis via miR-1290.

A case study of Lepiota brunneoincarnata poisoning with endoscopic nasobiliary drainage in Shandong, China.

The most frequently reported fatal Lepiota ingestions are due to L. brunneoincarnata. We present a case of L. brunneoincarnata poisoning with endoscopic nasobiliary drainage known to be the first in China. The patient suffered gastrointestinal symptoms 9 h post ingestion of mushrooms. The patient was hospitalized 4 days after eating the mushrooms with jaundice. The peak ALT, AST, APTT, TBIL and DBIL values of the patient were as follow: ALT, 2980 U/L (day 4 post ingestion); AST, 1910 U/L (day 4 post ingestion); APTT, 92.8 seconds (day 8 post ingestion), TBIL, 136 µmol/L (day 10 post ingestion), DBIL 74 µmol/L (day 10 post ingestion). UPLC-ESI-MS/MS was used to detect the peptide toxins in the mushroom and biological samples from the patient. We calculated that the patient may have ingested a total of 29.05 mg amatoxin from 300 g mushrooms, consisting of 19.91 mg α-amanitin, 9.1 mg ß-amanitin, and 0.044 mg γ-amanitin. Amatoxins could be detected in bile even on day 6 after ingestion of L. brunneoincarnata. With rehydration, endoscopic nasobiliary drainage and intravenous infusion of Legalon SIL, the patient recovered after serious hepatotoxicity developed.

Stem cells: a promising candidate to treat neurological disorders.

Neurologic impairments are usually irreversible as a result of limited regeneration in the central nervous system. Therefore, based on the regenerative capacity of stem cells, transplantation therapies of various stem cells have been tested in basic research and preclinical trials, and some have shown great prospects. This manuscript overviews the cellular and molecular characteristics of embryonic stem cells, induced pluripotent stem cells, neural stem cells, retinal stem/progenitor cells, mesenchymal stem/stromal cells, and their derivatives in vivo and in vitro as sources for regenerative therapy. These cells have all been considered as candidates to treat several major neurological disorders and diseases, owing to their self-renewal capacity, multi-directional differentiation, neurotrophic properties, and immune modulation effects. We also review representative basic research and recent clinical trials using stem cells for neurodegenerative diseases, including Parkinson's disease, Alzheimer's disease, and age-related macular degeneration, as well as traumatic brain injury and glioblastoma. In spite of a few unsuccessful cases, risks of tumorigenicity, and ethical concerns, most results of animal experiments and clinical trials demonstrate efficacious therapeutic effects of stem cells in the treatment of nervous system disease. In summary, these emerging findings in regenerative medicine are likely to contribute to breakthroughs in the treatment of neurological disorders. Thus, stem cells are a promising candidate for the treatment of nervous system diseases.

Effect of Biliary Drainage on the Toxicity and Toxicokinetics of Amanita exitialis in Beagles.

Amatoxin poisoning induces delayed-onset acute liver failure, which are responsible for more than 90% of deaths in mushroom poisoning. It has been postulated from animal and human studies that biliary drainage interrupting enterohepatic amatoxin circulation may affect amatoxin poisoning. Dogs were randomly divided into four groups of six animals each. In 20 mg/kg and 60 mg/kg with biliary drainage groups, after accepting bile drainage operation, beagles were fed Amanita exitialis powder (20 or 60 mg/kg) in starch capsules. In control and bile drainage groups, the beagle dogs were fed with empty capsules. They were assessed for toxicity signs, biochemical and pathological changes, and peptide toxins in plasma, urine and bile. The data were directly compared with those from our published studies on Amanita exitialis-exposed beagles without biliary drainage. Amatoxins were rapidly absorbed and eliminated from plasma after Amanita exitialis ingestion. Amatoxins in 0⁻1-day urine accounted for more than 90% of the total urine excretion, and amatoxins in bile accounted for less than 20% of the total urine and bile excretion. The dogs with biliary drainage showed less severe toxicity signs and biochemical and pathological changes and much lower internal exposure than dogs without biliary drainage. Biliary drainage caused a more than 70% reduction in intestinal amatoxin absorption and could reduce amatoxin absorption from the gastrointestinal tract.