Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Mucosal Immunol ; 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39251184

RESUMEN

Postoperative cognitive dysfunction (POCD) is a prevalent neurological complication that can impair learning and memory for days, months, or even years after anesthesia/surgery. POCD is strongly associated with an altered composition of the gut microbiota (dysbiosis), but the accompanying metabolic changes and their role in gut-brain communication and POCD pathogenesis remain unclear. Here, the present study reports that anesthesia/surgery in aged mice induces elevated intestinal indoleamine 2,3-dioxygenase (IDO) expression and activity, which shifts intestinal tryptophan (TRP) metabolism toward more IDO-catalyzed kynurenine (KYN) and less gut bacteria-catabolized indoleacetic acid (IAA). Both anesthesia/surgery and intraperitoneal KYN administration induce increased KYN levels that correlate with impaired spatial learning and memory, whereas dietary IAA supplementation attenuates the anesthesia/surgery-induced cognitive impairment. Mechanistically, anesthesia/surgery increases interferon-γ (IFN-γ)-producing group 1 innate lymphoid cells (ILC1) in the small intestine lamina propria and elevates intestinal IDO expression and activity, as indicated by the higher ratio of KYN to TRP. The IDO inhibitor 1-MT and antibodies targeting IFN-γ or ILCs mitigate anesthesia/surgery-induced cognitive dysfunction, suggesting that intestinal ILC1 expansion and the ensuing IFN-γ-induced IDO upregulation may be the primary pathway mediating the shift to the KYN pathway in POCD. The ILC1-KYN pathway in the intestine could be a promising therapeutic target for POCD.

2.
Toxicon ; 247: 107849, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-38971474

RESUMEN

Mushroom poisoning is a significant contributor to foodborne disease outbreaks in China. This study focuses on two Panaeolus subbalteatus poisoning incidents accompanied by epidemiological investigations, species identification, and toxin detection in Ningxia, northwest China. In these two poisoning incidents, some patients exhibited gastrointestinal or neurological symptoms approximately 0.5 h after ingestion of a large amount of wild mushroom. Specifically, in Case 1, one of the three patients experienced nausea, vomiting, and numbness in the throat and limbs; in Case 2, one patient reported dizziness and an abnormal sense of direction. Through morphological and phylogenetic analyses, mushroom specimens were identified as P. subbalteatus. Psilocybin and psilocin were detected in mushroom samples, and only psilocin was detected in biological samples by liquid chromatography-triple quadrupole-linear ion trap mass spectrometry screening. The average psilocybin and psilocin contents in mushroom samples were 1532.2-1760.7 and 114.5-136.0 mg/kg (n = 3), respectively. Moreover, only psilocin was detected in blood and urine samples, with average concentrations 0.5-1.2 ng/mL (n = 3) and 2.5-3.1 ng/mL (n = 3), respectively. These findings provide technical support for managing similar incidents in the future.


Asunto(s)
Intoxicación por Setas , Psilocibina , Intoxicación por Setas/diagnóstico , China , Psilocibina/análogos & derivados , Humanos , Triptaminas/análisis , Masculino , Adulto , Femenino , Filogenia , Persona de Mediana Edad
3.
Front Cell Infect Microbiol ; 13: 1215579, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37377645

RESUMEN

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.


Asunto(s)
Agaricales , Cortinarius , Agaricales/genética , Cortinarius/genética , Filogenia , ADN Espaciador Ribosómico/genética , Análisis de Secuencia de ADN , ADN de Hongos/genética , China
4.
Front Microbiol ; 14: 1151365, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36925482

RESUMEN

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.

5.
Cell Rep ; 42(3): 112163, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36827182

RESUMEN

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.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Histonas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Cromatina , Metilación , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
6.
Bioorg Med Chem ; 73: 117033, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36202064

RESUMEN

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.


Asunto(s)
Neoplasias , Humanos , Ácido Fólico , Neoplasias/tratamiento farmacológico , Proteolisis , Ubiquitina-Proteína Ligasas/metabolismo
7.
Toxicon ; 217: 155-161, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35998714

RESUMEN

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.


Asunto(s)
Agaricales , Intoxicación por Setas , Agaricales/química , Amanitinas/química , Muscarina , Intoxicación por Setas/diagnóstico , Faloidina
8.
Front Microbiol ; 13: 923435, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35859745

RESUMEN

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.

9.
Eur J Med Chem ; 231: 114144, 2022 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-35093670

RESUMEN

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).


Asunto(s)
Ectodermo , Neoplasias , Ectodermo/metabolismo , Ectodermo/patología , Proteína Potenciadora del Homólogo Zeste 2/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intercelular/uso terapéutico , Neoplasias/metabolismo , Complejo Represivo Polycomb 2
10.
MycoKeys ; 92: 79-93, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36761319

RESUMEN

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.

11.
Medicine (Baltimore) ; 100(51): e28040, 2021 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-34941044

RESUMEN

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).


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Humanos , Medicina Tradicional China/métodos , Estudios Multicéntricos como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Bazo , Resultado del Tratamiento , Microambiente Tumoral
12.
Nucleic Acids Res ; 49(18): 10448-10464, 2021 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-34570240

RESUMEN

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.


Asunto(s)
Proteínas Fúngicas/metabolismo , Fusarium/genética , Regulación Fúngica de la Expresión Génica , Histonas/metabolismo , Complejo Represivo Polycomb 2/metabolismo , ADN/metabolismo , Proteínas Fúngicas/química , Fusarium/metabolismo , Histonas/química , Lisina/metabolismo , Proteínas Represoras/metabolismo , Transcripción Genética
13.
J Integr Plant Biol ; 63(4): 707-722, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33438356

RESUMEN

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.


Asunto(s)
Epigénesis Genética/genética , Empalme Alternativo/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Elementos Transponibles de ADN/genética , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Heterocromatina/genética , Poliadenilación/genética , Poliadenilación/fisiología , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
14.
Nat Commun ; 11(1): 6212, 2020 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-33277495

RESUMEN

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.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Epigénesis Genética , Regulación de la Expresión Génica de las Plantas , Histonas/metabolismo , Complejos Multiproteicos/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Flores/genética , Flores/crecimiento & desarrollo , Flores/metabolismo , Regulación del Desarrollo de la Expresión Génica , Código de Histonas/genética , Lisina/metabolismo , Metilación , Modelos Moleculares , Complejos Multiproteicos/química , Complejos Multiproteicos/genética , Fosfoproteínas Fosfatasas/química , Fosfoproteínas Fosfatasas/genética , Fosfoproteínas Fosfatasas/metabolismo , Conformación Proteica , Factores de Tiempo
15.
Front Genet ; 11: 998, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32973889

RESUMEN

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.

16.
Cell Commun Signal ; 18(1): 135, 2020 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-32843056

RESUMEN

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.


Asunto(s)
Infecciones por Adenoviridae/complicaciones , Neoplasias Encefálicas/patología , Glioblastoma/patología , Células Madre Neoplásicas/patología , ARN Largo no Codificante/metabolismo , Factor de Transcripción STAT3/metabolismo , Receptor Toll-Like 9/metabolismo , Animales , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Transformación Celular Neoplásica/patología , Regulación Neoplásica de la Expresión Génica , Proteína HMGB1/metabolismo , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Factor 88 de Diferenciación Mieloide/metabolismo , Células Madre Neoplásicas/metabolismo , ARN Largo no Codificante/genética , Transducción de Señal , Esferoides Celulares/metabolismo , Esferoides Celulares/patología
17.
Chin J Nat Med ; 18(7): 550-560, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32616195

RESUMEN

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.


Asunto(s)
Bufanólidos/toxicidad , Cardiotoxicidad/etiología , Canales Iónicos/efectos de los fármacos , Miocitos Cardíacos/efectos de los fármacos , Células HEK293 , Humanos , Células Madre Pluripotentes Inducidas
18.
Toxicon ; 179: 72-75, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32345453

RESUMEN

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.


Asunto(s)
Muscarina/análisis , Intoxicación por Setas/diagnóstico , Agaricales/química , China , Humanos , Intoxicación por Setas/metabolismo , Toxinas Biológicas
19.
Cell Death Dis ; 10(12): 869, 2019 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-31740664

RESUMEN

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.


Asunto(s)
Caveolina 1/metabolismo , Células Endoteliales/metabolismo , Vesículas Extracelulares/metabolismo , MicroARNs/metabolismo , Neuronas/metabolismo , Animales , Apoptosis , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Regulación hacia Arriba
20.
Toxicon ; 161: 12-16, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30831147

RESUMEN

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.


Asunto(s)
Agaricales/química , Amanitinas/envenenamiento , Intoxicación por Setas/metabolismo , Intoxicación por Setas/terapia , Amanitinas/sangre , Amanitinas/orina , China , Drenaje/métodos , Humanos , Masculino , Persona de Mediana Edad , Intoxicación por Setas/sangre , Intoxicación por Setas/orina , Silimarina/uso terapéutico
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA