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1.
Arch Microbiol ; 206(7): 292, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849633

RESUMO

In recent years, the evolution of antibiotic resistance has led to the inefficacy of several antibiotics, and the reverse of resistance was a novel method to solve this problem. We previously demonstrated that matrine (Mat) and berberine hydrochloride (Ber) had a synergistic effect against multidrug-resistant Escherichia coli (MDREC). This study aimed to demonstrate the effect of Mat combined with Ber in reversing the resistance of MDREC. The MDREC was sequenced passaged in the presence of Mat, Ber, and a combination of Mat and Ber, which did not affect its growth. The reverse rate was up to 39.67% after MDREC exposed to Mat + Ber for 15 days. The strain that reversed resistance was named drug resistance reversed E. coli (DRREC) and its resistance to ampicillin, streptomycin, gentamicin, and tetracycline was reversed. The MIC of Gentamicin Sulfate (GS) against DRREC decreased 128-fold to 0.63 µg/mL, and it was stable within 20 generations. Furthermore, the susceptible phenotype of DRREC remained stable within 20 generations, as well. The LD50 of DRREC for chickens was 8.69 × 109 CFU/mL. qRT-PCR assays revealed that the transcript levels of antibiotic-resistant genes and virulence genes in the DRREC strain were significantly lower than that in the MDREC strain (P < 0.05). In addition, GS decreased the death, decreased the bacterial loading in organs, alleviated the injury of the spleen and liver, and decreased the cytokine levels in the chickens infected by the DRREC strain. In contrast, the therapeutic effect of GS in chickens infected with MDREC was not as evident. These findings suggest that the combination of Mat and Ber has potential for reversing resistance to MDREC.


Assuntos
Alcaloides , Antibacterianos , Berberina , Galinhas , Farmacorresistência Bacteriana Múltipla , Infecções por Escherichia coli , Escherichia coli , Gentamicinas , Matrinas , Testes de Sensibilidade Microbiana , Doenças das Aves Domésticas , Quinolizinas , Animais , Gentamicinas/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Berberina/farmacologia , Antibacterianos/farmacologia , Quinolizinas/farmacologia , Infecções por Escherichia coli/veterinária , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Alcaloides/farmacologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/tratamento farmacológico , Virulência/efeitos dos fármacos , Sinergismo Farmacológico
2.
J Mol Model ; 30(7): 200, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850372

RESUMO

CONTEXT: Given the diverse pathophysiological mechanisms underlying Alzheimer's disease, it is improbable that a single targeted drug will prove successful as a therapeutic strategy. Therefore, exploring various hypotheses in drug design is imperative. The sequestration of Fe(II) and Zn(II) cations stands out as a crucial mechanism based on the mitigation of reactive oxygen species. Moreover, inhibiting acetylcholinesterase represents a pivotal strategy to enhance acetylcholine levels in the synaptic cleft. This research aims to investigate the analogs of Huperzine A, documented in scientific literature, considering of these two hypotheses. Consequently, the speciation chemistry of these structures with Fe(II) and Zn(II) was scrutinized using quantum chemistry calculations, molecular docking simulations, and theoretical predictions of pharmacokinetics properties. From the pharmacokinetic properties, only two analogs, HupA-A1 and HupA-A2, exhibited a theoretical permeability across the blood-brain barrier; on the other hand, from a thermodynamic standpoint, the enantiomers of HupA-A2 showed negligible chelation values. The enantiomers with the most favorable interaction parameters were S'R'HupA-A1 (ΔGBIND = -40.0 kcal mol-1, fitness score = 35.5) and R'R'HupA-A1 (ΔGBIND = -35.5 kcal mol-1, fitness score = 22.61), being compared with HupA (ΔGBIND = -41.75 kcal mol-1, fitness score = 39.95). From this study, some prime candidates for promising drug were S'R'HupA-A1 and R'R'HupA-A1, primarily owing to their favorable thermodynamic chelating capability and potential anticholinesterase mechanism. METHODS: Quantum chemistry calculations were carried out at B3LYP/6-31G(d) level, considering the IEF-PCM(UFF) implicit solvent model for water. The coordination compounds were assessed using the Gibbs free energy variation and hard and soft acid theory. Molecular docking calculations were conducted using the GOLD program, based on the crystal structure of the acetylcholinesterase protein (PDB code = 4EY5), where the ChemScore function was employed with the active site defined as the region within a 15-Å radius around the centroid coordinates (X = -9.557583, Y = -43.910473, Z = 31.466687). Pharmacokinetic properties were predicted using SwissADME, focusing on Lipinski's rule of five.


Assuntos
Acetilcolinesterase , Alcaloides , Doença de Alzheimer , Inibidores da Colinesterase , Simulação de Acoplamento Molecular , Sesquiterpenos , Doença de Alzheimer/tratamento farmacológico , Alcaloides/química , Sesquiterpenos/química , Humanos , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Acetilcolinesterase/metabolismo , Acetilcolinesterase/química , Barreira Hematoencefálica/metabolismo , Termodinâmica , Zinco/química , Modelos Moleculares , Ferro/química , Ferro/metabolismo
3.
BMC Plant Biol ; 24(1): 499, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840069

RESUMO

BACKGROUND: Murraya tetramera Huang is a traditional Chinese woody medicine. Its leaves contain flavonoids, alkaloids, and other active compounds, which have anti-inflammatory and analgesic effects, as well as hypoglycemic and lipid-lowering effects, and anti-tumor effects. There are significant differences in the content of flavonoids and alkaloids in leaves during different growth cycles, but the synthesis mechanism is still unclear. RESULTS: In April 2021, new leaves (one month old) and old leaves (one and a half years old) of M. tetramera were used as experimental materials to systematically analyze the changes in differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) with transcriptomics and metabolomics technology. This was done to identify the signaling pathways of flavonoid and alkaloid synthesis. The results showed that the contents of total alkaloids and flavonoids in old leaves were significantly higher than those in new leaves. Thirteen flavonoid compounds, three isoflavone compounds, and nineteen alkaloid compounds were identified, and 125 and 48 DEGs related to flavonoid and alkaloid synthesis were found, respectively. By constructing the KEGG (Kyoto Encyclopedia of Genes and Genomes) network of DEGs and DAMs, it was shown that the molecular mechanism of flavonoid biosynthesis in M. tetramera mainly focuses on the "flavonoid biosynthetic pathway" and the "flavonoid and flavonol biosynthetic pathway". Among them, p-Coumaryl alcohol, Sinapyl alcohol, Phloretin, and Isoquercitrin were significantly accumulated in old leaves, the up-regulated expression of CCR (cinnamoyl-CoA reductase) might promote the accumulation of p-Coumaryl alcohol, upregulation of F5H (ferulate-5-hydroxylase) might promote Sinapyl alcohol accumulation. Alkaloids, including indole alkaloids, pyridine alkaloids, imidazole alkaloids, and quinoline alkaloids, were significantly accumulated in old leaves, and a total of 29 genes were associated with these substances. CONCLUSIONS: These data are helpful to better understand the biosynthesis of flavonoids and alkaloids in M. tetramera and provide a scientific basis for the development of medicinal components in M. tetramera.


Assuntos
Alcaloides , Flavonoides , Perfilação da Expressão Gênica , Metabolômica , Murraya , Folhas de Planta , Flavonoides/biossíntese , Flavonoides/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/genética , Alcaloides/metabolismo , Alcaloides/biossíntese , Murraya/genética , Murraya/metabolismo , Transcriptoma , Regulação da Expressão Gênica de Plantas
4.
Planta Med ; 90(7-08): 523-533, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38843792

RESUMO

Benzylisoquinoline alkaloids are the major bioactive components in Chelidonium majus, a plant that has a long usage history for the treatment of gastrointestinal ailments in European and Asian phytomedicine. This study reports on the development and application of a supercritical fluid chromatography technique for the simultaneous qualitative and quantitative determination of seven benzylisoquinoline alkaloids in under six minutes using a Viridis BEH 2-EP column and a modifier comprising methanol with 30% acetonitrile and 20 mM ammonium formate. The method was fully validated according to ICH guidelines showing, e.g., excellent linearity (≥ 0.9997) and maximum deviations for intraday and inter-day precision of 2.99 and 2.76%, respectively. The new supercritical fluid chromatography assay was not only employed for the analysis of several C. majus samples but was also used for the subsequent development of a fast centrifugal partition chromatography technique, whereby five benzylisoquinoline alkaloids could be isolated within approximately 2.5 h, with only two of them, protopine and chelidonine, requiring an additional purification step. To achieve this, a solvent system composed of chloroform/methanol/0.3 M hydrochloric acid was used in descending mode. By injecting 500 mg of crude extract, stylopine (1.93 mg), sanguinarine (0.57 mg), chelidonine (1.29 mg), protopine (1.95 mg), and coptisine (7.13 mg) could be obtained. The purity of compounds was confirmed by supercritical fluid chromatography and MS.


Assuntos
Alcaloides , Benzilisoquinolinas , Chelidonium , Chelidonium/química , Benzilisoquinolinas/isolamento & purificação , Benzilisoquinolinas/química , Benzilisoquinolinas/análise , Alcaloides/isolamento & purificação , Alcaloides/química , Alcaloides/análise , Cromatografia com Fluido Supercrítico/métodos , Extratos Vegetais/química , Benzofenantridinas/química , Benzofenantridinas/isolamento & purificação , Chelidonium majus
5.
Harmful Algae ; 135: 102635, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38830716

RESUMO

Ongoing research on cyanotoxins, driven by the socioeconomic impact of harmful algal blooms, emphasizes the critical necessity of elucidating the toxicological profiles of algal cell extracts and pure toxins. This study comprehensively compares Raphidiopsis raciborskii dissolved extract (RDE) and cylindrospermopsin (CYN) based on Daphnia magna assays. Both RDE and CYN target vital organs and disrupt reproduction, development, and digestion, thereby causing acute and chronic toxicity. Disturbances in locomotion, reduced behavioral activity, and weakened swimming capability in D. magna have also been reported for both RDE and CYN, indicating the insufficiency of conventional toxicity evaluation parameters for distinguishing between the toxic effects of algal extracts and pure cyanotoxins. Additionally, chemical profiling revealed the presence of highly active tryptophan-, humic acid-, and fulvic acid-like fluorescence compounds in the RDE, along with the active constituents of CYN, within a 15-day period, demonstrating the chemical complexity and dynamics of the RDE. Transcriptomics was used to further elucidate the distinct molecular mechanisms of RDE and CYN. They act diversely in terms of cytotoxicity, involving oxidative stress and response, protein content, and energy metabolism, and demonstrate distinct modes of action in neurofunctions. In essence, this study underscores the distinct toxicity mechanisms of RDE and CYN and emphasizes the necessity for context- and objective-specific toxicity assessments, advocating nuanced approaches to evaluate the ecological and health implications of cyanotoxins, thereby contributing to the precision of environmental risk assessments.


Assuntos
Alcaloides , Toxinas Bacterianas , Toxinas de Cianobactérias , Cianobactérias , Daphnia , Animais , Toxinas Bacterianas/toxicidade , Daphnia/efeitos dos fármacos , Alcaloides/toxicidade , Cianobactérias/química , Uracila/análogos & derivados , Uracila/toxicidade , Extratos Celulares/química , Extratos Celulares/farmacologia , Proliferação Nociva de Algas
6.
Front Public Health ; 12: 1361186, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841681

RESUMO

Background and aims: Several pharmacological interventions, such as nicotine replacement therapy (NRT), varenicline, and bupropion, have been approved for clinical use of smoking cessation. E-cigarettes (EC) are increasingly explored by many RCTs for their potentiality in smoking cessation. In addition, some RCTs are attempting to explore new drugs for smoking cessation, such as cytisine. This network meta-analysis (NMA) aims to investigate how these drugs and e-cigarettes compare regarding their efficacy and acceptability. Materials and methods: This systematic review and NMA searched all clinical studies on smoking cessation using pharmacological monotherapies or e-cigarettes published from January 2011 to May 2022 using MEDLINE, COCHRANE Library, and PsychINFO databases. NRTs were divided into transdermal (TDN) and oronasal nicotine (ONN) by administrative routes, thus 7 network nodes were set up for direct and indirect comparison. Two different indicators measured the efficacy: prevalent and continuous smoking abstinence. The drop-out rates measured the acceptability. Results: The final 40 clinical studies included in this study comprised 77 study cohorts and 25,889 participants. Varenicline is more effective intervention to assist in smoking cessation during 16-32 weeks follow-up, and is very likely to prompt dropout. Cytisine shows more effectiveness in continuous smoking cessation but may also lead to dropout. E-cigarettes and oronasal nicotine are more effective than no treatment in encouraging prevalent abstinence, but least likely to prompt dropout. Finally, transdermal nicotine delivery is more effective than no treatment in continuous abstinence, with neither significant effect on prevalent abstinence nor dropout rate. Conclusion: This review suggested and agreed that Varenicline, Cytisine and transdermal nicotine delivery, as smoking cessation intervention, have advantages and disadvantages. However, we had to have reservations about e-cigarettes as a way to quit smoking in adolescents.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Metanálise em Rede , Agentes de Cessação do Hábito de Fumar , Abandono do Hábito de Fumar , Dispositivos para o Abandono do Uso de Tabaco , Vareniclina , Humanos , Abandono do Hábito de Fumar/métodos , Sistemas Eletrônicos de Liberação de Nicotina/estatística & dados numéricos , Vareniclina/uso terapêutico , Dispositivos para o Abandono do Uso de Tabaco/estatística & dados numéricos , Agentes de Cessação do Hábito de Fumar/uso terapêutico , Alcaloides/uso terapêutico , Azocinas/uso terapêutico , Azocinas/administração & dosagem , Bupropiona/uso terapêutico , Quinolizinas/uso terapêutico , Nicotina/administração & dosagem , Alcaloides Quinolizidínicos
7.
Anal Chim Acta ; 1312: 342763, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38834278

RESUMO

Developing effective electrochemiluminescence (ECL) platforms is always an essential concern in highly sensitive bioanalysis. In this work, a low-triggering-potential ECL sensor was designed for detecting synthetic cathinone 3,4-methylenedioxypyrovalerone (MDPV) based on a dual-signal amplification strategy. Initially, a probe was created by integrating Ruthenium into the hollow porphyrin-based MOF (PCN-222) structure to decrease the excitation potential and enhance ECL performance without external co-reaction accelerators. Additionally, for the first time, photonic crystals (PCs) assembled from covalent organic frameworks (COFs) were employed to amplify the ECL signal, thereby increasing the photon flux and the loading capacity of the ECL emitter to enhance sensitivity of the sensor. In the presence of the target MDPV, the aptamer labeled with Ferrocene (Fc) experienced conformational changes, causing Fc to approach the luminophore and resulting in ECL quenching. This effect was attributed to aptamer's conformational changes induced by the target, directly correlating with the target concentration. The constructed sensor showed good linearity with the target MDPV concentration, covering a dynamic range from 1.0 × 10-14 to 1.0 × 10-6 g/L and achieved an ultra-low detection limit of 4.79 × 10-15 g/L. This work employed dual amplification strategies to enhance ECL signals effectively, providing a novel method for developing highly responsive and bioactive sensors.


Assuntos
Técnicas Eletroquímicas , Medições Luminescentes , Estruturas Metalorgânicas , Fótons , Pirrolidinas , Rutênio , Estruturas Metalorgânicas/química , Técnicas Eletroquímicas/métodos , Rutênio/química , Pirrolidinas/química , Alcaloides/química , Alcaloides/análise , Limite de Detecção
8.
Rapid Commun Mass Spectrom ; 38(16): e9833, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38837482

RESUMO

RATIONALE: This study developed a method for the rapid classification and identification of the chemical composition of Qingyan dropping pills (QDP) to provide the theoretical basis and data foundation for further in-depth research on the pharmacological substance basis of the formula and the selection of quality control indexes. METHODS: Ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) and data postprocessing technology were used to analyze the chemical composition of QDP. The fragmentation information on possible characteristic fragments and related neutral losses was summarized based on the literature and was compared with the MS data obtained from the assay, and thus a rapid classification and identification of chemical components in QDP could be achieved. RESULTS: A total of 73 compounds were identified, namely 24 flavonoids, 14 terpenoids, 30 organic acids and their esters, 3 alkaloids, and 2 phenylpropanoids. CONCLUSIONS: In this study, UHPLC-Q-TOF-MS and data postprocessing technology were used to realize the rapid classification and identification of the chemical constituents of QDP, which provided a comprehensive, efficient, and fast qualitative analysis method, a basis for further quality control and safe medication of QDP.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Espectrometria de Massas/métodos , Flavonoides/análise , Flavonoides/química , Alcaloides/análise , Alcaloides/química , Terpenos/análise , Terpenos/química
9.
Mol Biol Rep ; 51(1): 732, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38872006

RESUMO

BACKGROUND: The present study aimed to elucidate the potential anticancer activity and mechanism of P. harmala's alkaloid extract, harmine (HAR), and harmaline (HAL) in HCT-116 colorectal cancer cells. METHODS AND RESULTS: P. harmala's alkaloid was extracted from harmala seeds. HCT-116 cells were treated with P. harmala's alkaloid extract, HAR and HAL. Cytotoxicity was determined by MTT assay, apoptotic activity detected via flow cytometry and acridine orange (AO)/ethidium bromide (EB) dual staining, and cell cycle distribution analyzed with flow cytometry. The mRNA expression of Bcl-2-associated X protein (Bax) and glycogen synthase kinase-3 beta (GSK3ß) was measured by real-time PCR. Furthermore, the expression of Bax, Bcl-2, GSK3ß and p53 proteins, were determined by western blotting. The findings indicated that, P. harmala's alkaloids extract, HAR and HAL were significantly cytotoxic toward HCT116 cells after 24 and 48 h of treatment. We showed that P. harmala's alkaloid extract induce apoptosis and cell cycle arrest at G2 phase in the HCT116 cell line. Downregulation of GSK3ß and Bcl-2 and upregulation of Bax and p53 were observed. CONCLUSION: The findings of this study indicate that the P. harmala's alkaloid extract has anticancer activity and may be further investigated to develop future anticancer chemotherapeutic agents.


Assuntos
Apoptose , Neoplasias do Colo , Glicogênio Sintase Quinase 3 beta , Harmina , Peganum , Sementes , Humanos , Peganum/química , Células HCT116 , Apoptose/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Sementes/química , Harmina/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Proteína X Associada a bcl-2/metabolismo , Proteína X Associada a bcl-2/genética , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Alcaloides/farmacologia , Harmalina/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proliferação de Células/efeitos dos fármacos
10.
Respir Res ; 25(1): 242, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38877465

RESUMO

BACKGROUND: Silicosis represents a paramount occupational health hazard globally, with its incidence, morbidity, and mortality on an upward trajectory, posing substantial clinical dilemmas due to limited effective treatment options available. Trigonelline (Trig), a plant alkaloid extracted mainly from coffee and fenugreek, have diverse biological properties such as protecting dermal fibroblasts against ultraviolet radiation and has the potential to inhibit collagen synthesis. However, it's unclear whether Trig inhibits fibroblast activation to attenuate silicosis-induced pulmonary fibrosis is unclear. METHODS: To evaluate the therapeutic efficacy of Trig in the context of silicosis-related pulmonary fibrosis, a mouse model of silicosis was utilized. The investigation seeks to elucidated Trig's impact on the progression of silica-induced pulmonary fibrosis by evaluating protein expression, mRNA levels and employing Hematoxylin and Eosin (H&E), Masson's trichrome, and Sirius Red staining. Subsequently, we explored the mechanism underlying of its functions. RESULTS: In vivo experiment, Trig has been demonstrated the significant efficacy in mitigating SiO2-induced silicosis and BLM-induced pulmonary fibrosis, as evidenced by improved histochemical staining and reduced fibrotic marker expressions. Additionally, we showed that the differentiation of fibroblast to myofibroblast was imped in Trig + SiO2 group. In terms of mechanism, we obtained in vitro evidence that Trig inhibited fibroblast-to-myofibroblast differentiation by repressing TGF-ß/Smad signaling according to the in vitro evidence. Notably, our finding indicated that Trig seemed to be safe in mice and fibroblasts. CONCLUSION: In summary, Trig attenuated the severity of silicosis-related pulmonary fibrosis by alleviating the differentiation of myofibroblasts, indicating the development of novel therapeutic approaches for silicosis fibrosis.


Assuntos
Alcaloides , Diferenciação Celular , Fibroblastos , Camundongos Endogâmicos C57BL , Miofibroblastos , Fibrose Pulmonar , Dióxido de Silício , Silicose , Animais , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/prevenção & controle , Alcaloides/farmacologia , Dióxido de Silício/toxicidade , Camundongos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Diferenciação Celular/efeitos dos fármacos , Silicose/patologia , Silicose/metabolismo , Silicose/tratamento farmacológico , Masculino
11.
J Am Chem Soc ; 146(23): 16203-16212, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38829274

RESUMO

Baeyer-Villiger monooxygenases (BVMOs) play crucial roles in the core-structure modification of natural products. They catalyze lactone formation by selective oxygen insertion into a carbon-carbon bond adjacent to a carbonyl group (Baeyer-Villiger oxidation, BVO). The homologous bacterial BVMOs, BraC and PxaB, thereby process bicyclic dihydroindolizinone substrates originating from a bimodular nonribosomal peptide synthetase (BraB or PxaA). While both enzymes initially catalyze the formation of oxazepine-dione intermediates following the identical mechanism, the final natural product spectrum diverges. For the pathway involving BraC, the exclusive formation of lipocyclocarbamates, the brabantamides, was reported. The pathway utilizing PxaB solely produces pyrrolizidine alkaloids, the pyrrolizixenamides. Surprisingly, replacing pxaB within the pyrrolizixenamide biosynthetic pathway by braC does not change the product spectrum to brabantamides. Factors controlling this product selectivity have remained elusive. In this study, we set out to solve this puzzle by combining the total synthesis of crucial pathway intermediates and anticipated products with in-depth functional in vitro studies on both recombinant BVMOs. This work shows that the joint oxazepine-dione intermediate initially formed by both BVMOs leads to pyrrolizixenamides upon nonenzymatic hydrolysis, decarboxylative ring contraction, and dehydration. Brabantamide biosynthesis is enzyme-controlled, with BraC efficiently transforming all the accepted substrates into its cognate final product scaffold. PxaB, in contrast, shows only considerable activity toward brabantamide formation for the substrate analog with a natural brabantamide-type side chain structure, revealing substrate-controlled product selectivity.


Assuntos
Oxigenases de Função Mista , Oxigenases de Função Mista/metabolismo , Oxigenases de Função Mista/química , Alcaloides/química , Alcaloides/metabolismo , Biocatálise , Estrutura Molecular , Especificidade por Substrato
12.
Bioorg Chem ; 149: 107529, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38850780

RESUMO

Trace natural products (TNPs) are still the vital source of drug development. However, the mining of novel TNPs is becoming increasingly challenging due to their low abundance and complex interference. A comprehensive strategy was proposed in which the functionalized magnetic particles integrated with LC-MS for TNPs discovery. Under the guidance of the approach, fifteen trace Nuphar alkaloids including seven new ones, cyanopumiline A sulfoxide (1), cyanopumiline C sulfoxide (8) and cyanopumilines A-E (4-5, 10, 12-13) featuring an undescribed nitrile-containing 6/6/5/6/6 pentacyclic ring system were isolated from the rhizomes of Nuphar pumila. Their structures and absolute configurations were determined on the basis of detailed spectroscopic data analysis and single-crystal X-ray diffraction analysis. Notably, a concise method based on 13C NMR spectroscopy was established to determine the relative configurations of spiroatoms. Biologically, compounds 1-12 exhibited potent immunosuppressive activities with IC50 values ranging from 0.1-12.1 µM against anti-CD3/CD28 induced human peripheral T cell proliferation. Mechanistic studies revealed that 4 could dose-dependently decrease pro-inflammatory cytokines and the expression levels of CD25 and CD71.


Assuntos
Alcaloides , Proliferação de Células , Relação Dose-Resposta a Droga , Imunossupressores , Humanos , Proliferação de Células/efeitos dos fármacos , Imunossupressores/farmacologia , Imunossupressores/química , Imunossupressores/isolamento & purificação , Estrutura Molecular , Alcaloides/química , Alcaloides/farmacologia , Alcaloides/isolamento & purificação , Relação Estrutura-Atividade , Cromatografia Líquida , Descoberta de Drogas , Linfócitos T/efeitos dos fármacos , Espectrometria de Massas , Espectrometria de Massa com Cromatografia Líquida
13.
Bioorg Med Chem ; 108: 117776, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38852257

RESUMO

Myocardial ischemia/reperfusion (MI/R) is a common cardiovascular disease that seriously affects the quality of life and prognosis of patients. In recent years, matrine has attracted widespread attention in the treatment of cardiovascular diseases. This study designed, synthesized, and characterized 20 new matrine derivatives and studied their protective effects on ischemia-reperfusion injury through in vivo and in vitro experiments. Based on cellular assays, most newly synthesized derivatives have a certain protective effect on Hypoxia/Reoxygenation (H/R) induced H9C2 cell damage, with compound 22 having the best activity and effectively reducing cell apoptosis and necrosis. In vitro experimental data shows that compound 22 can significantly reduce the infarct size of rat myocardium and improve cardiac function after MI/R injury. In summary, compound 22 is a new potential cardioprotective agent that can promote angiogenesis and enhance antioxidant activity by activating ADCY5, CREB3l4, and VEGFA, thereby protecting myocardial cell apoptosis and necrosis induced by MI/R.


Assuntos
Alcaloides , Apoptose , Desenho de Fármacos , Matrinas , Traumatismo por Reperfusão Miocárdica , Quinolizinas , Ratos Sprague-Dawley , Alcaloides/farmacologia , Alcaloides/química , Alcaloides/síntese química , Animais , Quinolizinas/farmacologia , Quinolizinas/síntese química , Quinolizinas/química , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/patologia , Ratos , Apoptose/efeitos dos fármacos , Masculino , Relação Estrutura-Atividade , Estrutura Molecular , Cardiotônicos/farmacologia , Cardiotônicos/síntese química , Cardiotônicos/química , Relação Dose-Resposta a Droga , Linhagem Celular , Neovascularização Fisiológica/efeitos dos fármacos , Angiogênese
14.
Fa Yi Xue Za Zhi ; 40(2): 186-191, 2024 Apr 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38847035

RESUMO

OBJECTIVES: To explore the postmortem diffusion rule of Aconitum alkaloids and their metabolites in poisoned rabbits, and to provide a reference for identifying the antemortem poisoning or postmortem poisoning of Aconitum alkaloids. METHODS: Twenty-four rabbits were sacrificed by tracheal clamps. After 1 hour, the rabbits were administered with aconitine LD50 in decocting aconite root powder by intragastric administration. Then, they were placed supine and stored at 25 ℃. The biological samples from 3 randomly selected rabbits were collected including heart blood, peripheral blood, urine, heart, liver, spleen, lung and kidney tissues at 0 h, 4 h, 8 h, 12 h, 24 h, 48 h, 72 h and 96 h after intragastric administration, respectively. Aconitum alkaloids and their metabolites in the biological samples were analyzed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). RESULTS: At 4 h after intragastric administration, Aconitum alkaloids and their metabolites could be detected in heart blood, peripheral blood and major organs, and the contents of them changed dynamically with the preservation time. The contents of Aconitum alkaloids and their metabolites were higher in the spleen, liver and lung, especially in the spleen which was closer to the stomach. The average mass fraction of benzoylmesaconine metabolized in rabbit spleen was the highest at 48 h after intragastric administration. In contrast, the contents of Aconitum alkaloids and their metabolites in kidney were all lower. Aconitum alkaloids and their metabolites were not detected in urine. CONCLUSIONS: Aconitum alkaloids and their metabolites have postmortem diffusion in poisoned rabbits, diffusing from high-content organs (stomach) to other major organs and tissues as well as the heart blood. The main mechanism is the dispersion along the concentration gradient, while urine is not affected by postmortem diffusion, which can be used as the basis for the identification of antemortem and postmortem Aconitum alkaloids poisoning.


Assuntos
Aconitum , Alcaloides , Fígado , Espectrometria de Massas em Tandem , Animais , Coelhos , Aconitum/química , Alcaloides/metabolismo , Alcaloides/urina , Alcaloides/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Fígado/metabolismo , Rim/metabolismo , Pulmão/metabolismo , Aconitina/análogos & derivados , Aconitina/farmacocinética , Aconitina/urina , Aconitina/metabolismo , Aconitina/análise , Raízes de Plantas/química , Distribuição Tecidual , Baço/metabolismo , Mudanças Depois da Morte , Toxicologia Forense/métodos , Miocárdio/metabolismo , Fatores de Tempo , Masculino
15.
Pak J Pharm Sci ; 37(2(Special)): 463-473, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38822551

RESUMO

Solanum lyratum Thunb., a traditional Chinese herbal medicine, has a promising background. However, the anti-inflammatory effects of its component steroid alkaloid have not been explored. In this study, animal and cell experiments were performed to investigate the anti-inflammatory effects and mechanism of action of Solanum lyratum Thunb steroid alkaloid (SLTSA), in order to provide evidence for its potential utilization. SLTSA effectively inhibited ear swelling and acute abdominal inflammation of mice. We observed concentration-dependent inhibition of pro-inflammatory cytokines by SLTSA, as confirmed by the ELISA and RT-qPCR results. Flow cytometry, immunofluorescence and RT-qPCR analyses revealed that SLTSA suppressed TLR4 expression. Western blot results indicated that SLTSA inhibited the activation of the TLR4/MyD88/NF-κB signaling pathway. Our study demonstrated that SLTSA possesses anti-inflammatory properties.


Assuntos
Alcaloides , Anti-Inflamatórios , Transdução de Sinais , Solanum , Animais , Solanum/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/isolamento & purificação , Camundongos , Alcaloides/farmacologia , Alcaloides/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo , Citocinas/metabolismo , Células RAW 264.7 , Fator 88 de Diferenciação Mieloide/metabolismo , Masculino
16.
Food Res Int ; 188: 114439, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823829

RESUMO

Tropane alkaloids (TAs) are secondary metabolites from weeds that can contaminate cereals and vegetables during harvest. Due to their toxicity, the Regulation (EC) 2023/915 sets maximum levels for atropine and scopolamine in cereal-based foods for infants containing millet, sorghum, buckwheat or their derived products. The aim of this study was to evaluate the effect of pH and temperature on the stability of TAs, as possible parameters in thermal processing to mitigate this chemical hazard in cereal-based infant food. The effect of pH (4 and 7) and temperature (80 °C and 100 °C) was assessed in buffer solutions. Also, treatment at 180 °C was performed in spiked and naturally incurred millet flour to assess the effect of high temperature, simulating cooking or drying, on the stability of TAs in the cereal matrix. The fate of 24 TAs was assessed by UHPLC-MS/MS. TAs showed high thermostability, although it was variable depending on the specific compound, pH, temperature and treatment time. In buffer solutions, higher degradation was found at 100 °C and pH 7. In spiked millet flour at 180 °C for 10 min, scopolamine and atropine contents decreased by 25 % and 22 %, similarly to other TAs which also showed a slow thermal degradation. Atropine, scopolamine, anisodamine, norscopolamine, scopine and scopoline were found in naturally contaminated millet flour. Interestingly, naturally incurred atropine was more thermostable than when spiked, showing a protective effect of the cereal matrix on TAs degradation. The present results highlight the need for an accurate monitorization of TAs in raw materials, as this chemical hazard may remain in infant cereal-based food even after intense thermal processing.


Assuntos
Grão Comestível , Contaminação de Alimentos , Alimentos Infantis , Espectrometria de Massas em Tandem , Grão Comestível/química , Concentração de Íons de Hidrogênio , Alimentos Infantis/análise , Contaminação de Alimentos/prevenção & controle , Tropanos/química , Tropanos/análise , Temperatura , Alcaloides/análise , Humanos , Manipulação de Alimentos/métodos , Temperatura Alta , Atropina/análise , Atropina/química , Lactente , Cromatografia Líquida de Alta Pressão
17.
AAPS J ; 26(4): 70, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862871

RESUMO

Synthetic cathinones represent one of the largest and most abused new psychoactive substance classes, and have been involved in numerous intoxications and fatalities worldwide. Methcathinone analogues like 3-methylmethcathinone (3-MMC), 3-chloromethcathinone (3-CMC), and 4-CMC currently constitute most of synthetic cathinone seizures in Europe. Documenting their consumption in clinical/forensic casework is therefore essential to tackle this trend. Targeting metabolite markers is a go-to to document consumption in analytical toxicology, and metabolite profiling is crucial to support investigations. We sought to identify 3-CMC, 4-CMC, and 4-bromomethcathinone (4-BMC) human metabolites. The substances were incubated with human hepatocytes; incubates were screened by liquid chromatography-high-resolution tandem mass spectrometry and data were mined with Compound Discoverer (Themo Scientific). 3-CMC-positive blood, urine, and oral fluid and 4-CMC-positive urine and saliva from clinical/forensic casework were analyzed. Analyses were supported by metabolite predictions with GLORYx freeware. Twelve, ten, and ten metabolites were identified for 3-CMC, 4-CMC, and 4-BMC, respectively, with similar transformations occurring for the three cathinones. Major reactions included ketoreduction and N-demethylation. Surprisingly, predominant metabolites were produced by combination of N-demethylation and ω-carboxylation (main metabolite in 3-CMC-positive urine), and combination of ß-ketoreduction, oxidative deamination, and O-glucuronidation (main metabolite in 4-CMC-positive urine). These latter metabolites were detected in negative-ionization mode only and their non-conjugated form was not detected after glucuronide hydrolysis; this metabolic pathway was never reported for any methcathinone analogue susceptible to undergo the same transformations. These results support the need for comprehensive screening strategies in metabolite identification studies, to avoid overlooking significant metabolites and major markers of consumption.


Assuntos
Hepatócitos , Humanos , Hepatócitos/metabolismo , Hepatócitos/efeitos dos fármacos , Espectrometria de Massas em Tandem/métodos , Propiofenonas/farmacocinética , Propiofenonas/metabolismo , Cromatografia Líquida/métodos , Detecção do Abuso de Substâncias/métodos , Metanfetamina/análogos & derivados , Metanfetamina/metabolismo , Metanfetamina/administração & dosagem , Metanfetamina/farmacocinética , Psicotrópicos/farmacocinética , Psicotrópicos/metabolismo , Psicotrópicos/administração & dosagem , Metabolômica/métodos , Alcaloides/metabolismo , Drogas Ilícitas
18.
Theor Appl Genet ; 137(7): 155, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858311

RESUMO

White lupin (Lupinus albus L.) is a high-protein grain legume alternative to soybean in Central Europe, but its cultivation is risky due to the fungal disease anthracnose that can cause severe yield damage. In addition, management of seed alkaloids is critical for human nutrition and animal feed. We report on a white lupin collection of genebank accessions, advanced breeding lines and cultivars that was genotyped and phenotypically characterized for anthracnose resistance and seed alkaloids and protein levels. Using genotyping by sequencing (GBS), SeqSNP-targeted GBS, BiomarkX genotyping and Sanger sequencing, a genetic resource of genome-wide SNPs for white lupin was established. We determined anthracnose resistance in two years field trials at four locations with infection rows and measured seed alkaloids and protein levels by near-infrared spectroscopy (NIRS). Few white lupin breeding lines showed anthracnose resistance comparable or better than Celina and Frieda, currently the best commercial cultivars in Germany. NIRS estimates for seed alkaloids and protein levels revealed variation in the white lupin collection. Using genome-wide association studies (GWAS), we identified SNPs significantly associated with anthracnose resistance in the field representing known and new genomic regions. We confirmed the pauper locus and detected new SNP markers significantly associated with seed alkaloids. For the first time, we present loci associated with total grain protein content. Finally, we tested the potential of genomic prediction (GP) in predicting the phenotype of these three quantitative traits. Application of results and resources are discussed in the context of fostering breeding programs for white lupin.


Assuntos
Alcaloides , Resistência à Doença , Lupinus , Fenótipo , Doenças das Plantas , Polimorfismo de Nucleotídeo Único , Sementes , Lupinus/genética , Lupinus/microbiologia , Resistência à Doença/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Sementes/genética , Sementes/química , Genótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Melhoramento Vegetal , Estudos de Associação Genética
19.
Int J Biol Macromol ; 272(Pt 1): 132738, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38825269

RESUMO

Piperine (PIP) has been known for its pharmacological activities with low water solubility and poor dissolution, which limits its nutritional application. The purpose of this research was to enhance PIP stability, dispersibility and biological activity by preparing PIP nanoparticles using the wet-media milling approach combined with nanosuspension solidification methods of spray/freeze drying. Octenyl succinic anhydride (OSA)-modified waxy maize starch was applied as the stabilizer to suppress aggregation of PIP nanoparticles. The particle size, redispersibility, storage stability and in vitro release behavior of PIP nanoparticles were measured. The regulating effect on adipocyte differentiation was evaluated using 3T3-L1 cell model. Results showed that PIP nanoparticles had a reduced particle size of 60 ± 1 nm, increased release rate in the simulated gastric (SGF) and intestinal fluids (SIF) and enhanced inhibition effect on adipogenesis in 3T3-L1 cells compared with free PIP, indicating that PIP-loaded nanoparticles with improved stability and anti-adipogenic property were developed successfully by combining wet-media milling and drying methods.


Assuntos
Células 3T3-L1 , Adipócitos , Adipogenia , Alcaloides , Benzodioxóis , Nanopartículas , Piperidinas , Alcamidas Poli-Insaturadas , Amido , Animais , Camundongos , Nanopartículas/química , Alcamidas Poli-Insaturadas/química , Alcamidas Poli-Insaturadas/farmacologia , Benzodioxóis/farmacologia , Benzodioxóis/química , Piperidinas/farmacologia , Piperidinas/química , Adipogenia/efeitos dos fármacos , Alcaloides/química , Alcaloides/farmacologia , Adipócitos/efeitos dos fármacos , Amido/química , Amido/análogos & derivados , Tamanho da Partícula , Liberação Controlada de Fármacos , Diferenciação Celular/efeitos dos fármacos
20.
Drug Dev Res ; 85(4): e22219, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38845211

RESUMO

Sepsis is a life-threatening organ dysfunction that endangers patient lives and is caused by an imbalance in the host defense against infection. Sepsis continues to be a significant cause of morbidity and mortality in critically sick patients. Oxymatrine (OMT), a quinolizidine alkaloid derived from the traditional Chinese herb Sophora flavescens Aiton, has been shown to have anti-inflammatory effects on a number of inflammatory illnesses according to research. In this study, we aimed to evaluate the therapeutic effects of OMT on sepsis and explore the underlying mechanisms. We differentiated THP-1 cells into THP-1 macrophages and studied the anti-inflammatory mechanism of OMT in a lipopolysaccharide (LPS)-induced THP-1 macrophage sepsis model. Activation of the receptor for advanced glycation end products (RAGE), as well as NF-κB, was assessed by Western blot analysis and immunofluorescence staining. ELISA was used to measure the levels of inflammatory factors. We found that OMT significantly inhibited HMGB1-mediated RAGE/NF-κB activation and downstream inflammatory cytokine production in response to LPS stimulation. Finally, an in vivo experiment was performed on septic mice to further study the effect of OMT on injured organs. The animal experiments showed that OMT significantly inhibited HMGB1-mediated RAGE/NF-κB activation, protected against the inflammatory response and organ injury induced by CLP, and prolonged the survival rate of septic mice. Herein, we provide evidence that OMT exerts a significant therapeutic effect on sepsis by inhibiting the HMGB1/RAGE/NF-κB signaling pathway.


Assuntos
Alcaloides , Proteína HMGB1 , Inflamação , Lipopolissacarídeos , NF-kappa B , Quinolizinas , Receptor para Produtos Finais de Glicação Avançada , Sepse , Transdução de Sinais , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Quinolizinas/farmacologia , Quinolizinas/uso terapêutico , Animais , Sepse/tratamento farmacológico , Sepse/complicações , Sepse/metabolismo , NF-kappa B/metabolismo , Proteína HMGB1/metabolismo , Proteína HMGB1/antagonistas & inibidores , Humanos , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Transdução de Sinais/efeitos dos fármacos , Camundongos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Masculino , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Células THP-1 , Camundongos Endogâmicos C57BL , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Matrinas
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