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1.
Toxicon ; 241: 107688, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484849

RESUMO

Amanita phalloides poisoning is known to be the most fatal case among mushroom poisoning cases. Its main mechanism of toxicity is that it leads to cell death by the irreversible binding of its toxins to the DNA-dependent RNA polymerase II enzyme. This study was planned to analyze the effects of the CDP-choline molecule on Amanita phalloides mushroom poisoning cases. The extract of the Amanita phalloides mushroom was taken and intraperitoneally administered to male Wistar Albino rats at a dose of 0.3 g/kg. In the experiment phase, the rats were divided into three groups of CDP-choline treatment according to the doses of 100 mg/kg, 250 mg/kg, and 500 mg/kg, and one control group was administered a 1 ml/kg dose of 0.9% isotonic NaCl solution. The treatments were then administered intraperitoneally at the 2nd hour, and at the 6th hour, the rats were sacrificed. The degree of damage in the liver and kidney tissues of the rats was evaluated histopathologically. It was concluded that CDP-choline reduced or prevented the damage that occurred in the liver significantly and dose-dependently in the toxicosis picture caused by Amanita phalloides, and it showed a tendency to lower or prevent the damage in the kidney, albeit not significantly.


Assuntos
Intoxicação Alimentar por Cogumelos , Masculino , Ratos , Animais , Intoxicação Alimentar por Cogumelos/tratamento farmacológico , Ratos Wistar , Amanita/química , Colina
2.
Food Chem ; 448: 139086, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38520990

RESUMO

Amanita exitialis, a deadly mushroom found in eastern Asia, causes the highest death rates among all poisonous mushrooms in China. The aim of the present study was to develop an efficient, accurate, and user-friendly PCR-based method for identifying A. exitialis that could facilitate the prevention, diagnosis, and treatment of associated food poisoning. A. exitialis-specific primers and probes were designed based on the internal transcribed spacer region variations of 27 mushroom species. Specificity was confirmed using conventional and real-time PCR for 23 non-target mushroom species, including morphologically similar and closely related species. Compared to conventional PCR, real-time PCR was more sensitive (detectable DNA concentration: 1.36 × 10-2 ng/µL vs. 1.36 × 10-3) and efficient (analysis time: 1 h vs. 40 min). Furthermore, the real-time PCR results could be immediately visualized using amplification curve analysis. The results present two robust PCR-based methods for A. exitialis identification that can facilitate food safety.


Assuntos
Amanita , DNA Fúngico , Reação em Cadeia da Polimerase em Tempo Real , Amanita/genética , Amanita/química , Amanita/classificação , DNA Fúngico/genética , Primers do DNA/genética , Reação em Cadeia da Polimerase , China , Intoxicação Alimentar por Cogumelos/diagnóstico
3.
Se Pu ; 41(11): 976-985, 2023 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-37968816

RESUMO

The discovery and identification of mushroom toxins has long been an important area in the fields of toxicology and food safety. Mushrooms are widely favored for their culinary and medicinal value; however, the presence of potentially lethal toxins in some species poses a substantial challenge in ensuring their safe consumption. Therefore, the development of a robust and sensitive analytical method is necessary for accurately identifying the risks associated with mushroom consumption. The study of mushroom toxins, which are characterized by their diversity and substantial variations in chemical structures, present a considerable challenge for achieving precise and high-throughput analysis. To address this issue, the present study employed a robust approach combining a solid-phase extraction (SPE) purification technique with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to establish an analytical method for the detection and quantification of five amatoxins and two tryptamines (psilocybin and bufotenine) present in some mushrooms. Several optimization procedures were undertaken, including optimizing the chromatographic conditions, mass spectrometric parameters, and sample extraction and purification. The procedure involved the extraction of dry mushroom powder with methanol containing 0.3% formic acid, followed by purification using a strong cation exchange cartridge (SCX). The analytes were separated on a T3 chromatographic column (100 mm×2.1 mm, 1.8 µm) using mobile phases of acetonitrile and 5 mmol/L ammonium acetate solution containing 0.1% formic acid. The multiple reaction monitoring (MRM) mode was employed for data acquisition. Amatoxins were quantified using matrix-matched standard calibration curves, whereas isotopic internal standards were used to quantify tryptamine. The results showed that all seven toxins exhibited good linearities (r2>0.99) within the optimized concentration range. The limits of detection (LODs) for bufotenine, psilocybin, and amatoxins were determined as 2.0, 5.0, and 10 µg/kg, respectively, while the limits of quantification (LOQs) were determined as 5.0, 10, and 20 µg/kg, respectively. The LOD and LOQ values further underscore the ability of the method to detect minute quantities of toxins, making it particularly well suited for screening food samples for potential contamination. Using dried shiitake mushroom powder as the matrix, the recoveries of the two tryptamines ranged from 80.6% to 117%, with relative standard deviations (RSDs) ranging from 1.73% to 5.98%, while the recoveries of amatoxins ranged from 71.8% to 115%, with RSDs varying from 2.14% to 9.92% at the three concentration levels. The consistent and satisfactory recoveries of amatoxins and tryptamines demonstrated the ability of this method to accurately quantify the target analytes even in a complex matrix. Comparison with the results of supplementary test method recognized by State Administration for Market Regulation for food (BJS 202008) demonstrated comparable results, indicating no significant differences (p>0.05) in amatoxin contents. The newly developed method is rapid, accurate, precise, meets the required standards, and is suitable for the detection of seven toxins in wild mushrooms. As part of the application of this method, a comprehensive investigation of the distribution of toxins in wild mushrooms from Fujian Province was undertaken. In this study, 59 wild mushroom samples from nine cities were collected in the Fujian province. Species identification was conducted using rDNA-internal transcribed space (rDNA-ITS) molecular barcode technology, which revealed the presence of toxins in the two samples. Notably, one specimen named Amanita fuligineoides contained α-amanitin, ß-amanitin, and phalloidin in quantities of 607, 377, and 69.0 mg/kg, respectively. Additionally, another sample, identified as Tricholomataceae, had a psilocybin concentration of 12.6 mg/kg.


Assuntos
Amanita , Micotoxinas , Cromatografia Líquida de Alta Pressão , Amanita/química , Espectrometria de Massas em Tandem , Psilocibina , Bufotenina , Pós , Triptaminas , DNA Ribossômico
4.
Toxicon ; 226: 107067, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36871921

RESUMO

Approximately 70%∼90% of mushroom poisoning deaths are caused by the class of mushroom toxins known as amatoxins. However, the rapid elimination of amatoxins from plasma within 48 h after mushroom ingestion limits the practical value of plasma amatoxin analysis as a diagnostic indicator of Amanita mushroom poisoning. To increase the positive detection rate and extend the detection window of amatoxin poisoning, we developed a new method to detect protein-bound α-amanitin based on the hypothesis that RNAP II-bound α-amanitin released from the tissue into the plasma could be degraded by trypsin hydrolysis and then detected by conventional liquid chromatography-mass spectrometry (LC‒MS). Toxicokinetic studies on mice intraperitoneally injected with 0.33 mg/kg α-amanitin were conducted to obtain and compare the concentration trends, detection rates, and detection windows of both free α-amanitin and protein-bound α-amanitin. By comparing detection results with and without trypsin hydrolysis in the liver and plasma of α-amanitin-poisoned mice, we verified the credibility of this method and the existence of protein-bound α-amanitin in plasma. Under the optimized trypsin hydrolysis conditions, we obtained a time-dependent trend of protein-bound α-amanitin in mouse plasma at 1-12 days postexposure. In contrast to the short detection window (0-4 h) of free α-amanitin in mouse plasma, the detection window of protein-bound α-amanitin was extended to 10 days postexposure, with a total detection rate of 53.33%, ranging from the limit of detection to 23.94 µg/L. In conclusion, protein-bound α-amanitin had a higher positive detection rate and a longer detection window than free α-amanitin in mice.


Assuntos
Alfa-Amanitina , Intoxicação Alimentar por Cogumelos , Animais , Camundongos , Intoxicação Alimentar por Cogumelos/diagnóstico , Tripsina/metabolismo , Amanitinas/química , Cromatografia Líquida , Amanita/química
5.
Toxicon ; 212: 55-61, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35398159

RESUMO

Mushroom poisoning is a deeply concerning food safety problem that affects the public in China every year. Although there are statistics on the number of poisonings and incidents, there is a lack of data on the types of toxic mushrooms, clinical manifestations and toxins. A case of wild mushroom poisoning occurred in Xiamen. Descriptive epidemiological investigation, toxins detection, and morphological and phylogenetic identification were immediately performed. The patients exhibited typical neurotoxic symptoms after consuming wild mushrooms, including chills, vertigo, drowsiness, salivation and coma. The average incubation period was 30 min. Treatments that were adopted included fluid infusion, gastric lavage, catharsis, and liver protection treatment. All patients recovered within 10 days. The species was identified as Amanita pseudosychnopyramis, and its contents of muscarine, muscimol and ibotenic acid were 170.3 ± 5.9 mg/kg, 835.4 ± 43.1 mg/kg and 637.9 ± 54.8 mg/kg in dry weight, respectively, as detected by ultrahigh-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). To our knowledge, this is the first report of Amanita pseudosychnopyramis poisoning worldwide.


Assuntos
Intoxicação Alimentar por Cogumelos , Amanita/química , Cromatografia Líquida , Humanos , Intoxicação Alimentar por Cogumelos/diagnóstico , Intoxicação Alimentar por Cogumelos/epidemiologia , Intoxicação Alimentar por Cogumelos/terapia , Filogenia , Espectrometria de Massas em Tandem
6.
Food Funct ; 12(21): 11009-11023, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34657936

RESUMO

Alzheimer's disease (AD) leads to progressive declines in memory and learning. This disease may arise from endoplasmic reticulum stress due to protein misfolding, which promotes inflammatory pathway activation and induces neuronal cell apoptosis. Polysaccharide is one of the main active components of the mushroom Amanita caesarea (A. caesarea) and has been proven to act as an antioxidant, immune regulatory and anti-inflammatory agent with neurodevelopmental effects. In this study, polysaccharide isolated from A. caesarea (ACPS2) was subjected to analysis to determine the main components, homogeneity and molecular weight and characterize the structure. Furthermore, APP/PS1 mice were orally treated with ACPS2 for 6 weeks. Structural characterization of ACPS2 revealed a mass average molar mass of 16.6 kDa and a structure containing a main chain and branching. In vivo, treatment with ACPS2 for 6 weeks significantly improved cognition and anxious behavior in APP/PS1 mice using Morris water maze and open-field test. Alleviation of brain injury, amyloid-ß deposition and tau hyperphosphorylation were observed in ACPS2-treated AD mice. No changes in other tissues were observed. ACPS2 appeared to alleviate inflammation in vivo, as determined by decreases in the serum concentrations of tumor necrosis factor-α and interleukin-1ß relative to those in non-treated mice. ACPS2 improved cholinergic system function and stabilized oxidative stress in APP/PS1 mice. Proteomics and bioinformatics analyses showed that the therapeutic effect of ACPS2 is achieved through regulation of oxidative stress-mediated endoplasmic reticulum stress. Furthermore, ACPS2 exerted anti-AD effects by regulating nuclear factor-E2-related factor 2 (Nrf2) signaling, thereby inhibiting endoplasmic reticulum stress and nuclear factor-kappa B (NF-κB) activation.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Amanita/química , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Polissacarídeos Fúngicos/química , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Masculino , Memória , Camundongos , Camundongos Transgênicos , Presenilina-1/genética , Presenilina-1/metabolismo
7.
Se Pu ; 39(3): 338-345, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-34227315

RESUMO

Amanita peptide toxins are cyclic polypeptide mushroom toxins that can cause acute liver damage. The fatality rate associated with these toxins is very high. Monitoring the concentration of amanita peptide toxins in human urine can provide valuable information for early clinical diagnosis and treatment. Therefore, a TurboFlow online clean-up-liquid chromatography-triple quadrupole mass spectrometry (TF-LC-MS/MS) method was established for the simultaneous quantitative determination of five amanita peptide toxins (α-amanitin, ß-amanitin, γ-amanitin, phallacidin, and phalloidin) in human urine. After pre-treatment with high-speed centrifugation, urine samples were analyzed using TF-LC-MS/MS. The main factors influencing purification efficiency, including the TF column, loading solution, eluting solution, transfer flow, and transfer time, were optimized in this study. Under the optimized experimental conditions, the analytes were purified using a TurboFlowTM Cyclone column (50 mm×0.5 mm) and separated on a Hypersil GOLD C18 column (100 mm×2.1 mm) using the mobile phases of methanol and 4 mmol/L aqueous ammonium acetate solution with gradient elution. The analytes were detected in selected reaction monitoring (SRM) mode via positive electrospray ionization. Matrix-matched external standard calibration was used for quantitation. The linear range of the method ranged from 1.0 µg/L to 50.0 µg/L for all five amanita peptide toxins, with correlation coefficients (r2) higher than 0.997. The limits of detection were 0.15-0.3 µg/L and the limits of quantification (LOQs) were 0.5-1.0 µg/L for the five amanita peptide toxins in urine. The intra-day and inter-day recoveries of amanita peptide toxins were 87.0%-108.6% and 86.8%-112.7%, respectively, at the spiked levels of 2.0, 5.0, and 10.0 µg/L. The intra-day and inter-day relative standard deviations (RSDs) were less than 14.5%. The method is accurate, rapid, sensitive, easy to operate, and can satisfy the requirements of public health emergency testing or clinical poisoning testing.


Assuntos
Amanita/química , Cromatografia Líquida , Intoxicação Alimentar por Cogumelos/diagnóstico , Micotoxinas , Espectrometria de Massas em Tandem , Humanos , Micotoxinas/urina
8.
Toxicol Lett ; 346: 1-6, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33872745

RESUMO

Amanitin poisonings are among the most life-threatening mushroom poisonings, and are mainly caused by the genus Amanita. Hepatotoxicity is the hallmark of amanitins, powerful toxins contained in these mushrooms, and can require liver transplant. Among amatoxins, α-amanitin is the most studied. However, the hypothesis of a possible metabolism of amanitins is still controversial in this pathophysiology. Therefore, there is a need of clarification using cutting-edge tools allowing metabolism study. Molecular network has emerged as powerful tool allowing metabolism study through organization and representation of untargeted tandem mass spectrometry (MS/MS) data in a graphical form. The aim of this study is to investigate amanitin metabolism using molecular networking. In vivo (four positive amanitin urine samples) and in vitro (differentiated HepaRG cells supernatant incubated with α-amanitin 2 µM for 24 h) samples were extracted and analyzed by LC-HRMS/MS using a Q Exactive™ Orbitrap mass spectrometer. Using molecular networking on both in vitro and in vivo, we have demonstrated that α-amanitin does not undergo metabolism in human. Thus, we provide solid evidence that a possible production of amanitin metabolites cannot be involved in its toxicity pathways. These findings can help to settle the debate on amanitin metabolism and toxicity.


Assuntos
Alfa-Amanitina/metabolismo , Alfa-Amanitina/química , Alfa-Amanitina/urina , Amanita/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Estrutura Molecular , Intoxicação Alimentar por Cogumelos/urina
10.
Nat Prod Res ; 35(4): 649-654, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30931629

RESUMO

As part of our systematic study on Korean toxic mushrooms, bioactivity-guided fractionation of the MeOH extract of Amanita spissacea (Amanitaceae) fruiting bodies and chemical investigation of its cytotoxic fractions led to the isolation of (9E)-8-oxo-9-octadecenoic acid (1), (10E)-9-oxo-10-octadecenoic acid (2), (9E)-8-oxo-9-octadecenoate methyl ester (3), (9Z)-9-octadecenoate-(2'S)-2',3'-dihydroxypropyl ester (4), (9Z)-9-octadecenoic acid (5), and palmitic acid (6). The structures of the isolates were elucidated by NMR spectroscopic analysis and LC/MS analysis. Among the isolated compounds, compounds 1 and 2 exhibited the most potent cytotoxic activity in all human lung cancer cell lines examined, with IC50 values ranging from 255.7 to 321.0 µM and 250.2 to 322.5 µM, respectively. The cytotoxicity of these compounds was also found to be mediated by apoptosis associated with caspase-3 activation. These findings provide experimental evidence suggesting the potential of A. spissacea as a promising natural source for the discovery of novel anticancer drug candidates.


Assuntos
Amanita/química , Apoptose/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Forma Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Humanos , Metanol , Extratos Vegetais/farmacologia
11.
Food Chem ; 329: 127146, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32526599

RESUMO

A non-target screening method of cyclopeptide toxins and their analogues in mushroom was developed, using ultra-high-performance liquid chromatography coupled with quadrupole Orbitrap mass spectrometry (UHPLC-Q-Orbitrap MS) followed by mass spectrometry databases retrieval and software tools analysis for the candidate analogues. Three cyclopeptide toxins in the toxic mushroom Amanita rimosa were firstly screened without standard, and two of them were unknown analogues which were tentatively identified by the accurate masses, isotopic patterns and characteristic fragments. A validated quantitative method was performed to rapidly quantify three major cyclopeptide toxins in the Amanita rimosa sample including α-manitin, ß-amanitin and phalloidin, and their contents were detected to be 4.52 mg/kg, 2.37 mg/kg and 2.53 mg/kg, respectively. The developed method has good selectivity and sensitivity for rapid and comprehensive screening the cyclopeptide toxins and their analogues in mushrooms at trace levels. Successful non-target screening of trace cyclopeptide toxin analogues will guarantee the food safety in mushrooms consumption.


Assuntos
Alfa-Amanitina/química , Amanita/química , Amanitinas/química , Faloidina/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas
12.
PLoS One ; 15(4): e0231781, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32302363

RESUMO

The mushroom poison that causes the most deaths is the class of toxins known as amatoxins. Current methods to sensitively and selectively detect these toxins are limited by the need for expensive equipment, or they lack accuracy due to cross-reactivity with other chemicals found in mushrooms. In this work, we report the development of a competition-based lateral flow immunoassay (LFIA) for the rapid, portable, selective, and sensitive detection of amatoxins. Our assay clearly indicates the presence of 10 ng/mL of α-AMA or γ-AMA and the method including extraction and detection can be completed in approximately 10 minutes. The test can be easily read by eye and has a presumed shelf-life of at least 1 year. From testing 110 wild mushrooms, the LFIA identified 6 out of 6 species that were known to contain amatoxins. Other poisonous mushrooms known not to contain amatoxins tested negative by LFIA. This LFIA can be used to quickly identify amatoxin-containing mushrooms.


Assuntos
Amanita/química , Amanitinas/análise , Imunoensaio/métodos , Amanitinas/química , Anticorpos/química , Ouro/química , Peptídeos/toxicidade , Padrões de Referência
13.
Molecules ; 25(7)2020 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-32235328

RESUMO

The fully automated system of single drop microextraction coupled with capillary electrophoresis (SDME-CE) was developed for in-line preconcentration and determination of muscimol (MUS) and psilocin (PSC) from urine samples. Those two analytes are characteristic active metabolites of Amanita and Psilocybe mushrooms, evoking visual and auditory hallucinations. Study analytes were selectively extracted from the donor phase (urine samples, pH 4) into the organic phase (a drop of octanol layer), and re-extracted to the acidic acceptor (background electrolyte, BGE), consisting of 25 mM phosphate buffer (pH 3). The optimized conditions for the extraction procedure of a 200 µL urine sample allowed us to obtain more than a 170-fold enrichment effect. The calibration curves were linear in the range of 0.05-50 mg L-1, with the correlation coefficients from 0.9911 to 0.9992. The limit of detections was determined by spiking blank urine samples with appropriate standards, i.e., 0.004 mg L-1 for PSC and 0.016 mg L-1 for MUS, respectively. The limits of quantification varied from 0.014 mg L-1 for PSC and 0.045 mg L-1 for MUS. The developed method practically eliminated the sample clean-up step, which was limited only to simple dilution (1:1, v/v) and pH adjustment.


Assuntos
Amanita/química , Alucinógenos/urina , Microextração em Fase Líquida/métodos , Muscimol/urina , Psilocybe/química , Psilocibina/análogos & derivados , Calibragem , Eletroforese Capilar , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Psilocibina/urina , Solventes/química
14.
Fungal Biol ; 124(3-4): 174-182, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32220378

RESUMO

There is growing evidence that mushrooms (fruiting bodies) can be suitable for biogeochemical prospecting for minerals and as indicators of heavy metal and radioactive contaminants in the terrestrial environment. Apart from the nutritional aspect, knowledge of accumulation dynamics and distribution of elements in fruiting bodies, from emergence to senescence, is essential as is standardization when choosing mushroom species as potential bioindicators and for monitoring purposes. We studied the effect of fruitbody developmental stage on the contents of the elements (Li, K, V, Cr, Mn, Mg, Co, Ni, Cu, Zn, As, Rb, Sr, Ag, Al, Cd, Sb, Cs, Ba, Pb, Tl and U) in the individual parts of the Amanita muscaria fruiting body. Elements such as K, Mg, Mn, Ni, Co, Cu, Zn and Se remained similar throughout all developmental stages studied, however for K, differences occurred in the values of caps and stipes, as expressed by the cap to stipe concentration quotient (index QC/S). The other elements quantified, i.e., Li, V, Cr, As, Rb, Sr, Ag, Al, Cd, Sb, Cs, Ba, Pb, Tl and U are considered as nonessential or toxic (with the exception of V in A. muscaria). Their accumulation in the fruiting bodies and their distribution between cap and stipe did not show a uniform pattern. Pb, Sb, Tl, Ba, Sr, Li, Rb and Cs decreased with increasing maturity of the fruitbodies, implying that translocation, distribution and accumulation in stipes and caps was not a continuous process, while V, Cr, As, Ag, Cd, and U remained at the same concentration, similarly to the essential elements. Our results for A. muscaria confirm that elemental distribution in different parts of fruiting bodies is variable for each element and may change during maturation. Soil properties, species specificity and the pattern of fruitbody development may all contribute to the various types of elemental distribution and suggest that the results for one species in one location may have only limited potential for generalization.


Assuntos
Amanita/química , Metais , Amanita/metabolismo , Arsênio/análise , Monitorização de Parâmetros Ecológicos/métodos , Elementos Químicos , Florestas , Carpóforos/química , Carpóforos/crescimento & desenvolvimento , Metais/análise , Metais Pesados/análise , Minerais/análise , Solo/química
15.
Magn Reson Chem ; 58(6): 584-593, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31912552

RESUMO

The biologically active alkaloid muscimol is present in fly agaric mushroom (Amanita muscaria), and its structure and action is related to human neurotransmitter γ -aminobutyric acid (GABA). The current study reports on determination of muscimol form present in water solution using multinuclear 1 H and 13 C nuclear magnetic resonance (NMR) experiments supported by density functional theory molecular modeling. The structures of three forms of free muscimol molecule both in the gas phase and in the presence of water solvent, modeled by polarized continuous model, and nuclear magnetic isotropic shieldings, the corresponding chemical shifts, and indirect spin-spin coupling constants were calculated. Several J-couplings observed in proton and carbon NMR spectra, not available before, are reported. The obtained experimental spectra, supported by theoretical calculations, favor the zwitterion form of muscimol in water. This structure differs from NH isomer, previously determined in dimethyl sulfoxide (DMSO) solution. In addition, positions of signals C3 and C5 are reversed in both solvents.


Assuntos
Amanita/química , Antagonistas de Receptores de GABA-A/química , Muscimol/química , Água/química , Isótopos de Carbono , Teoria da Densidade Funcional , Antagonistas de Receptores de GABA-A/isolamento & purificação , Antagonistas de Receptores de GABA-A/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Muscimol/isolamento & purificação , Muscimol/farmacologia , Prótons , Receptores de GABA/metabolismo
17.
Angew Chem Int Ed Engl ; 59(14): 5500-5504, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-31846557

RESUMO

The toxic bicyclic octapeptide α-amanitin is mostly found in different species of the mushroom genus Amanita, with the death cap (Amanita phalloides) as one of the most prominent members. Due to its high selective inhibition of RNA polymerase II, which is directly linked to its high toxicity, particularly to hepatocytes, α-amanitin received an increased attention as a toxin-component of antibody-drug conjugates (ADC) in cancer research. Furthermore, the isolation of α-amanitin from mushrooms as the sole source severely restricts compound supply as well as further investigations, as structure-activity relationship (SAR) studies. Based on a straightforward access to the non-proteinogenic amino acid dihydroxyisoleucine, we herein present a robust total synthesis of α-amanitin providing options for production at larger scale as well as future structural diversifications.


Assuntos
Alfa-Amanitina/síntese química , Alfa-Amanitina/química , Amanita/química , Amanita/metabolismo , Ciclização , Imunoconjugados/química , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/química , Relação Estrutura-Atividade
18.
J Nat Prod ; 82(12): 3489-3493, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31724396

RESUMO

Amanita pantherina is a poisonous mushroom that causes muscle cramps, insanity, and audiovisual disorders. As part of our systematic study on Korean mushrooms, a chemical investigation of A. pantherina fruiting bodies resulted in the isolation and structural identification of three new fatty acid derivatives, pantheric acids A-C (1-3), and a known compound, 1,10-dimethyl ester-2-decenedioic acid (4). Although 1,10-dimethyl ester-2-decenedioic acid (4) was previously reported as a synthetic product, it was structurally identified from a natural source for the first time. The structures of the new compounds were established by detailed analysis of 1D and 2D (1H-1H COSY, HSQC, and HMBC) NMR, HRMS, and LC/MS/MS data. The absolute configurations of compounds 1 and 2 were unambiguously determined by a recently developed method using competing enantioselective acylation coupled with LC/MS analysis. The isolated compounds (1-4) were evaluated for their effects on lipid accumulation during adipocyte maturation. Pantheric acids A-C (1-3) promoted the enlargement of lipid droplets in 3T3-L1 adipocytes and altered lipid metabolism by inducing lipogenesis and inhibiting lipolysis. Our findings provide experimental evidence suggesting the potential adverse effects of pantheric acids A-C from a poisonous mushroom on lipid metabolism.


Assuntos
Adipócitos/efeitos dos fármacos , Amanita/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Camundongos , Estrutura Molecular , Análise Espectral/métodos
19.
Sud Med Ekspert ; 62(4): 58-60, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31407708

RESUMO

Eating mushrooms known to contain amatoxin is fraught with serious complications. The analysis of the relevant literature publications revealed no article with the description of the histological picture of the internal organs in the subjects intoxicated with amatoxin. It is known, however, that such poisoning is associated with the severe irreversible injuries to all intracellular protein structures the character of which depends on time. Specifically, acute amatoxin intoxication produces the well apparent clinical picture within 6 days after intake of the poison. It is characterized by acute renal and hepatic insufficiency in the combination with the injury to the conducting system of heart and the myocrardium itself. Thereafter, the disseminated intravascular coagulation (DIC) syndrome developed accompanied by the signs of progressive tissue hypoxia that ended in death on day 9. The histological study has demonstrated necrotic foci in the liver and oedematous hepatic stroma. Kidneys underwent multiple hemorrhages, necrosis of convoluted tubules and well apparent hydropic protein dystrophy of their epithelium. The adrenal glands showed up signs of necrosis and hemorrhage. It is concluded that poisoning with mushrooms (amatoxin) should be regarded as the most probable cause of the condition requiring differential diagnostics between acute gastroenteritis and renal insufficiency.


Assuntos
Amanita/química , Amanitinas/envenenamento , Rim/patologia , Fígado/patologia , Intoxicação Alimentar por Cogumelos/diagnóstico , Humanos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos
20.
Food Chem Toxicol ; 132: 110687, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31325463

RESUMO

Muscimol is the main compound found in Amanita muscaria. Several studies have proven that muscimol has suppressive effects on essential tremor, without impairing speech and coordination. The effects of muscimol in Parkinson-affected patients is also described in a number of studies. These studies describe the free radical scavenging and antioxidant activity of the mushroom extract. We have evaluated the possible neuroprotective effects of a standardized extract from A. muscaria, containing high amounts of muscimol, on different models of neurotoxicity in rat brain microsomes, mitochondria, synaptosomes as well as on neuroblastoma cell line SH-SY5Y. The possible inhibitory effect on human recombinant monoaminoxidase-B (hMAOB) enzyme was also studied. The extract revealed statistically significant neuroprotective effects on the in vitro neurotoxicity models and no inhibitory activity on hMAOB.


Assuntos
Amanita/química , Muscimol/farmacologia , Animais , Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Masculino , Monoaminoxidase/efeitos dos fármacos , Muscimol/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Organelas/efeitos dos fármacos , Ratos , Ratos Wistar
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