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1.
Food Res Int ; 186: 114333, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729693

RESUMO

Acrylamide is an amide formed in the Maillard reaction, with asparagine as the primary amino acid precursor. The intake of large amounts of acrylamide has induced genotoxic and carcinogenic effects in hormone-sensitive tissues of animals. The enzime asparaginase is one of the most effective methods for lowering the formation of acrylamide in foods such as potatoes. However, the reported sensory outcomes for coffee have been unsatisfactory so far. This study aimed to produce coffees with reduced levels of acrylamide by treating them with asparaginase while retaining their original sensory and bioactive profiles. Three raw samples of Coffea arabica, including two specialty coffees, and one of Coffea canephora were treated with 1000, 2000, and 3000 ASNU of the enzyme. Asparagine and bioactive compounds (chlorogenic acids-CGA, caffeine, and trigonelline) were quantified in raw and roasted beans by HPLC and LC-MS, while the determination of acrylamide and volatile organic compounds was performed in roasted beans by CG-MS. Soluble solids, titratable acidity, and pH were also determined. Professional cupping by Q-graders and consumer sensory tests were also conducted. Results were analyzed by ANOVA-Fisher, MFA, PCA and Cluster analyses, with significance levels set at p ≤ 0.05. Steam treatment alone decreased acrylamide content by 18.4%, on average, and 6.1% in medium roasted arabica and canefora coffees. Average reductions of 32.5-56.0% in acrylamide formation were observed in medium roasted arabica beans when 1000-3000 ASNU were applied. In the canefora sample, 59.4-60.7% reductions were observed. However, steam treatment primarily caused 17.1-26.7% reduction of total CGA and lactones in medium roasted arabica samples and 13.9-22.0% in canefora sample, while changes in trigonelline, caffeine, and other evaluated chemical parameters, including the volatile profiles were minimal. Increasing enzyme loads slightly elevated acidity. The only sensory changes observed by Q-graders and or consumers in treated samples were a modest increase in acidity when 3000 ASNU was used in the sample with lower acidity, loss of mild off-notes in control samples, and increased perception of sensory descriptors. The former was selected given the similarity in chemical outcomes among beans treated with 2000 and 3000 ASNU loads.


Assuntos
Acrilamida , Asparaginase , Asparagina , Coffea , Café , Paladar , Acrilamida/análise , Asparagina/análise , Coffea/química , Café/química , Humanos , Compostos Orgânicos Voláteis/análise , Culinária/métodos , Alcaloides/análise , Ácido Clorogênico/análise , Cafeína/análise , Masculino , Manipulação de Alimentos/métodos , Reação de Maillard , Temperatura Alta , Cromatografia Líquida de Alta Pressão , Sementes/química , Feminino
2.
J Agric Food Chem ; 72(19): 10897-10908, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38691522

RESUMO

Gramine (GRM), which occurs in Gramineae plants, has been developed to be a biological insecticide. Exposure to GRM was reported to induce elevations of serum ALT and AST in rats, but the mechanisms of the observed hepatotoxicity have not been elucidated. The present study aimed to identify reactive metabolites that potentially participate in the toxicity. In rat liver microsomal incubations fortified with glutathione or N-acetylcysteine, one oxidative metabolite (M1), one glutathione conjugate (M2), and one N-acetylcysteine conjugate (M3) were detected after exposure to GRM. The corresponding conjugates were detected in the bile and urine of rats after GRM administration. CYP3A was the main enzyme mediating the metabolic activation of GRM. The detected GSH and NAC conjugates suggest that GRM was metabolized to a quinone imine intermediate. Both GRM and M1 showed significant toxicity to rat primary hepatocytes.


Assuntos
Ativação Metabólica , Citocromo P-450 CYP3A , Hepatócitos , Ratos Sprague-Dawley , Animais , Ratos , Masculino , Hepatócitos/metabolismo , Hepatócitos/efeitos dos fármacos , Citocromo P-450 CYP3A/metabolismo , Citocromo P-450 CYP3A/genética , Microssomos Hepáticos/metabolismo , Glutationa/metabolismo , Inseticidas/toxicidade , Inseticidas/metabolismo , Alcaloides/metabolismo
3.
Nat Prod Res ; 38(11): 1864-1873, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38739563

RESUMO

Phytochemical studies of the stems and leaves of Stephania dielsiana Y.C.Wu yielded two new aporphine alkaloids (1 and 5), along with six known alkaloids (2-4 and 6-8). Their structures were characterised based on analyses of spectroscopic data, including one- and two-dimensional nuclear magnetic resonance (NMR) spectroscopy and high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS). The cytotoxic activities of the isolated compounds against a small panel of tumour cell lines were assessed by MTS assay. Interestingly, compound 2 exhibited particularly strong cytotoxic activities against HepG2, MCF7 and OVCAR8 cancer cell lines, with IC50 values of 3.20 ± 0.18, 3.10 ± 0.06 and 3.40 ± 0.007 µM, respectively. Furthermore, molecular docking simulations were carried out to explore the interactions and binding mechanisms of the most active compound (compound 2) with proteins. Our results contribute to understanding the secondary metabolites produced by S. dielsiana and provide a scientific rationale for further investigations of cytotoxicity of this valuable medicinal plant.


Assuntos
Alcaloides , Antineoplásicos Fitogênicos , Aporfinas , Simulação de Acoplamento Molecular , Folhas de Planta , Caules de Planta , Stephania , Aporfinas/química , Aporfinas/farmacologia , Humanos , Folhas de Planta/química , Caules de Planta/química , Alcaloides/química , Alcaloides/farmacologia , Stephania/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Estrutura Molecular , Linhagem Celular Tumoral , Células Hep G2 , Células MCF-7 , Ensaios de Seleção de Medicamentos Antitumorais , Espectroscopia de Ressonância Magnética , Plantas Medicinais/química
4.
Molecules ; 29(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731459

RESUMO

Terpenoid alkaloids are recognized as a class of compounds with limited numbers but potent biological activities, primarily derived from plants, with a minor proportion originating from animals and microorganisms. These alkaloids are synthesized from the same prenyl unit that forms the terpene skeleton, with the nitrogen atom introduced through ß-aminoethanol, ethylamine, or methylamine, leading to a range of complex and diverse structures. Based on their skeleton type, they can be categorized into monoterpenes, sesquiterpenes, diterpenes, and triterpene alkaloids. To date, 289 natural terpenoid alkaloids, excluding triterpene alkaloids, have been identified in studies published between 2019 and 2024. These compounds demonstrate a spectrum of biological activities, including anti-inflammatory, antitumor, antibacterial, analgesic, and cardioprotective effects, making them promising candidates for further development. This review provides an overview of the sources, chemical structures, and biological activities of natural terpenoid alkaloids, serving as a reference for future research and applications in this area.


Assuntos
Alcaloides , Terpenos , Alcaloides/química , Alcaloides/farmacologia , Terpenos/química , Terpenos/farmacologia , Humanos , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Estrutura Molecular
5.
Drug Alcohol Depend ; 258: 111280, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38614019

RESUMO

The most prevalent psychoactive chemical in tobacco smoke is nicotine, which has been shown to maintain tobacco consumption as well as cause acute adverse effects at high doses, like nausea and emesis. Recent studies in laboratory animals have suggested that many non-nicotine constituents of tobacco smoke (e.g., minor tobacco alkaloids) may also contribute to tobacco's overall reinforcing and adverse effects. Here, we used intravenous (IV) self-administration (n = 3) and observation (n = 4) procedures in squirrel monkeys to, respectively, compare the reinforcing and adverse observable effects of nicotine and three prominent minor tobacco alkaloids, nornicotine, anatabine, and myosmine. In self-administration studies, male squirrel monkeys were trained to respond under a second-order fixed-interval schedule of reinforcement and dose-effects functions for nicotine and each of the minor tobacco alkaloids nornicotine, anatabine, and mysomine were determined. Observation studies were conducted in a different group of male squirrel monkeys to quantify the ability of nicotine, nornicotine, anatabine, and mysomine to produce adverse overt effects, including hypersalivation, emesis, and tremors. Results show that nicotine and to a lesser extent nornicotine were readily self-administered, whereas anatabine and myosmine were not. In observation studies, all minor tobacco alkaloids produced adverse observable effects that were either comparable or more pronounced than nicotine. Collectively, the present results showing that nicotine and the minor tobacco alkaloids nornicotine, anatabine, and myosmine produce differential reinforcing and acute adverse observable effects in monkeys provides further evidence that these constituents may differently contribute to the psychopharmacological and adverse effects of tobacco consumption.


Assuntos
Alcaloides , Nicotiana , Nicotina , Reforço Psicológico , Saimiri , Autoadministração , Animais , Masculino , Relação Dose-Resposta a Droga , Condicionamento Operante/efeitos dos fármacos
6.
Zhongguo Zhong Yao Za Zhi ; 49(4): 868-883, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621894

RESUMO

Scorpio is a valuable Chinese animal medicine commonly used in clinical practice in China. It is the main drug in the treatment of liver wind internal movement caused by various reasons throughout the history of traditional Chinese medicine(TCM), with the effects of relieving wind and spasm, dredging collaterals, relieving pain, and eliminating toxin and mass. Scorpio is poisonous and often used as medicine after processing. There are records of its processing as early as the Song Dynasty. Afterward, there were more than 15 processing methods, including frying with vinegar, neat processing, and stir-frying. After processing, the fishy smell could be removed to correct the taste, and the toxicity could be reduced, which was beneficial to clinical application. At present, the main reported components in Scorpio are protein polypeptides, alkaloids, and lipids, with many pharmacological effects, such as anti-cancer, anti-coagulation, anti-thrombosis, anti-atherosclerosis, and anti-bacteria. In this study, the historical evolution of processing, chemical constituents, and pharmacological action of Scorpio were discussed in order to provide references for the related research on Scorpio.


Assuntos
Alcaloides , Medicamentos de Ervas Chinesas , Animais , Evolução Química , Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Chinesa , Alcaloides/farmacologia
7.
Mar Drugs ; 22(4)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38667758

RESUMO

Nemertean worms contain toxins that are used to paralyze their prey and to deter potential predators. Hoplonemerteans often contain pyridyl alkaloids like anabaseine that act through nicotinic acetylcholine receptors and crustacean chemoreceptors. The chemical reactivity of anabaseine, the first nemertean alkaloid to be identified, has been exploited to make drug candidates selective for alpha7 subtype nAChRs. GTS-21, a drug candidate based on the anabaseine scaffold, has pro-cognitive and anti-inflammatory actions in animal models. The circumpolar chevron hoplonemertean Amphiporus angulatus contains a multitude of pyridyl compounds with neurotoxic, anti-feeding, and anti-fouling activities. Here, we report the isolation and structural identification of five new compounds, doubling the number of pyridyl alkaloids known to occur in this species. One compound is an isomer of the tobacco alkaloid anatabine, another is a unique dihydroisoquinoline, and three are analogs of the tetrapyridyl nemertelline. The structural characteristics of these ten compounds suggest several possible pathways for their biosynthesis.


Assuntos
Alcaloides , Isoquinolinas , Animais , Alcaloides/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Isoquinolinas/farmacologia , Isoquinolinas/química , Isoquinolinas/isolamento & purificação , Invertebrados/química , Piridinas/farmacologia , Piridinas/química , Piridinas/isolamento & purificação , Receptores Nicotínicos/metabolismo , Receptores Nicotínicos/efeitos dos fármacos , Estrutura Molecular
8.
Eur J Med Chem ; 271: 116406, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38688064

RESUMO

NRAS mutation is the second most common oncogenic factor in cutaneous melanoma. Inhibiting NRAS translation by stabilizing the G-quadruplex (G4) structure with small molecules seems to be a potential strategy for cancer therapy due to the NRAS protein's lack of a druggable pocket. To enhance the effects of previously reported G4 stabilizers quindoline derivatives, we designed and synthesized a novel series of quindoline derivatives with fork-shaped side chains by introducing (alkylamino)alkoxy side chains. Panels of experimental results showed that introducing a fork-shaped (alkylamino)alkoxy side chain could enhance the stabilizing abilities of the ligands against NRAS RNA G-quadruplexes and their anti-melanoma activities. One of them, 10b, exhibited good antitumor activity in the NRAS-mutant melanoma xenograft mouse model, showing the therapeutic potential of this kind of compounds.


Assuntos
Antineoplásicos , Desenho de Fármacos , Quadruplex G , GTP Fosfo-Hidrolases , Proteínas de Membrana , Quadruplex G/efeitos dos fármacos , Humanos , Animais , GTP Fosfo-Hidrolases/metabolismo , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Relação Estrutura-Atividade , Estrutura Molecular , Melanoma/tratamento farmacológico , Melanoma/patologia , Relação Dose-Resposta a Droga , Proliferação de Células/efeitos dos fármacos , Indóis/farmacologia , Indóis/química , Indóis/síntese química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , RNA/metabolismo , RNA/química , Biossíntese de Proteínas/efeitos dos fármacos , Alcaloides , Quinolinas
9.
Molecules ; 29(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38611869

RESUMO

The fascaplysin and homofascaplysin class of marine natural products has a characteristic 12H-pyrido[1,2-a:3,4-b']diindole pentacyclic structure. Fascaplysin was isolated in 1988 from the marine sponge Fascaplysinopsis bergquist sp. The analogs of fascaplysin, such as homofascaplysins A, B, and C, were discovered late in the Fijian sponge F. reticulate, and also have potent antimicrobial activity and strong cytotoxicity against L-1210 mouse leukemia. In this review, the total synthesis of fascaplysin and its analogs, such as homofascaplysins A, B, and C, will be reviewed, which will offer useful information for medicinal chemistry researchers who are interested in the exploration of marine alkaloids.


Assuntos
Alcaloides , Antineoplásicos , Produtos Biológicos , Carbolinas , Indóis , Indolizinas , Poríferos , Compostos de Amônio Quaternário , Animais , Camundongos , Alcaloides/farmacologia , Bandagens
10.
Molecules ; 29(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38611934

RESUMO

Spirotryprostatin alkaloids, a class of alkaloids with a unique spirocyclic indoledionepiperazine structure, were first extracted from the fermentation broth of Aspergillus fumigatus and have garnered significant attention in the fields of biology and pharmacology. The investigation into the pharmacological potential of this class of alkaloids has unveiled promising applications in drug discovery and development. Notably, certain spirotryprostatin alkaloids have demonstrated remarkable anti-cancer activity, positioning them as potential candidates for anti-tumor drug development. In recent years, organic synthetic chemists have dedicated efforts to devise efficient and viable strategies for the total synthesis of spirotryprostatin alkaloids, aiming to meet the demands within the pharmaceutical domain. The construction of the spiro-C atom within the spirotryprostatin scaffold and the chirality control at the spiro atomic center emerge as pivotal aspects in the synthesis of these compounds. This review categorically delineates the synthesis of spirotryprostatin alkaloids based on the formation mechanism of the spiro-C atom.


Assuntos
Alcaloides , Fermentação , Aspergillus fumigatus , Descoberta de Drogas
12.
Sci Rep ; 14(1): 9483, 2024 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664520

RESUMO

The present study predicts the molecular targets and druglike properties of the phyto-compound piperine (PIP) by in silico studies including molecular docking simulation, druglikeness prediction and ADME analysis for prospective therapeutic benefits against diabetic complications. PIP was encapsulated in biodegradable polymer poly-lactide-co-glycolide (PLGA) to form nanopiperine (NPIP) and their physico-chemical properties were characterized by AFM and DLS. ∼ 30 nm sized NPIP showed 86.68% encapsulation efficiency and - 6 mV zeta potential, demonstrated great interactive stability and binding with CT-DNA displaying upsurge in molar ellipticity during CD spectroscopy. NPIP lowered glucose levels in peripheral circulation by > 65 mg/dL compared to disease model and improved glucose influx in alloxan-induced in vivo and in vitro diabetes models concerted with 3-folds decrease in ROS production, ROS-induced DNA damage and 27.24% decrease in nuclear condensation. The 25% increase in % cell viability and inhibition in chromosome aberration justified the initiation of p53 and PARP DNA repairing protein expression and maintenance of Hsp90. Thus, the experimental study corroborated well with in silico predictions of modulating the p53/PARP-1/Hsp90 axis, with predicted dock score value of - 8.72, - 8.57, - 8.76 kcal/mol respectively, validated docking-based preventive approaches for unravelling the intricacies of molecular signalling and nano-drug efficacy as therapeutics for diabetics.


Assuntos
Alcaloides , Benzodioxóis , Proteínas de Choque Térmico HSP90 , Hiperglicemia , Simulação de Acoplamento Molecular , Piperidinas , Poli(ADP-Ribose) Polimerase-1 , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Alcamidas Poli-Insaturadas , Proteína Supressora de Tumor p53 , Proteína Supressora de Tumor p53/metabolismo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Animais , Piperidinas/farmacologia , Piperidinas/química , Benzodioxóis/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Hiperglicemia/tratamento farmacológico , Hiperglicemia/metabolismo , Alcaloides/farmacologia , Alcaloides/química , Alcaloides/administração & dosagem , Alcamidas Poli-Insaturadas/farmacologia , Alcamidas Poli-Insaturadas/química , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Aloxano , Ratos , Humanos , Masculino , Espécies Reativas de Oxigênio/metabolismo , Camundongos , Nanopartículas/química , Dano ao DNA/efeitos dos fármacos
13.
Molecules ; 29(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38675582

RESUMO

Piper betle leaf powder is increasingly utilised as a health supplement. In this study, P. betle leaves were subjected to four different drying methods: convective air-drying, oven-drying, sun-drying, and no drying, with fresh leaves as control. Their antioxidant properties were then evaluated using colourimetric assays and GC-MS. Results showed that the sun-dried leaves had the highest (p < 0.05) total antioxidant capacity (66.23 ± 0.10 mg AAE/g), total polyphenol content (133.93 ± 3.76 mg GAE/g), total flavonoid content (81.25 ± 3.26 mg CE/g) and DPPH radical scavenging activity (56.48 ± 0.11%), and the lowest alkaloid content (45.684 ± 0.265 mg/gm). GC-MS analysis revealed that major constituents of aqueous extracts of fresh and sun-dried P. betle leaves were hydrazine 1,2-dimethyl-; ethyl aminomethylformimidate; glycerin; propanoic acid, 2-hydroxy-, methyl ester, (+/-)-; and 1,2-Cyclopentanedione. In conclusion, sun-dried leaves exhibited overall better antioxidant properties, and their aqueous extracts contained biologically active phytoconstituents that have uses in various fields.


Assuntos
Antioxidantes , Dessecação , Piper betle , Extratos Vegetais , Folhas de Planta , Folhas de Planta/química , Antioxidantes/química , Antioxidantes/farmacologia , Piper betle/química , Extratos Vegetais/química , Dessecação/métodos , Flavonoides/química , Flavonoides/análise , Polifenóis/química , Polifenóis/análise , Cromatografia Gasosa-Espectrometria de Massas , Alcaloides/química , Alcaloides/análise
14.
Molecules ; 29(8)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38675664

RESUMO

The integration of a multidimensional treatment dominated by active ingredients of traditional Chinese medicine (TCM), including enhanced chemotherapy and synergistically amplification of oxidative damage, into a nanoplatform would be of great significance for furthering accurate and effective cancer treatment with the active ingredients of TCM. Herein, in this study, we designed and synthesized four matrine-proteolysis-targeting chimeras (PROTACs) (depending on different lengths of the chains named LST-1, LST-2, LST-3, and LST-4) based on PROTAC technology to overcome the limitations of matrine. LST-4, with better anti-tumor activity than matrine, still degrades p-Erk and p-Akt proteins. Moreover, LST-4 NPs formed via LST-4 self-assembly with stronger anti-tumor activity and glutathione (GSH) depletion ability could be enriched in lysosomes through their outstanding enhanced permeability and retention (EPR) effect. Then, we synthesized LST-4@ZnPc NPs with a low-pH-triggered drug release property that could release zinc(II) phthalocyanine (ZnPc) in tumor sites. LST-4@ZnPc NPs combine the application of chemotherapy and phototherapy, including both enhanced chemotherapy from LST-4 NPs and the synergistic amplification of oxidative damage, through increasing the reactive oxygen species (ROS) by photodynamic therapy (PDT), causing an GSH decrease via LST-4 mediation to effectively kill tumor cells. Therefore, multifunctional LST-4@ZnPc NPs are a promising method for killing cancer cells, which also provides a new paradigm for using natural products to kill tumors.


Assuntos
Alcaloides , Glutationa , Indóis , Isoindóis , Matrinas , Quinolizinas , Espécies Reativas de Oxigênio , Alcaloides/química , Alcaloides/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Quinolizinas/química , Quinolizinas/farmacologia , Glutationa/metabolismo , Humanos , Animais , Indóis/química , Indóis/farmacologia , Camundongos , Linhagem Celular Tumoral , Compostos de Zinco/química , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Fotoquimioterapia/métodos , Proteólise , Nanopartículas/química
15.
Ecotoxicol Environ Saf ; 276: 116288, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38581909

RESUMO

Cylindrospermopsin (CYN), a cyanobacterial toxin, has been detected in the global water environment. However, information concerning the potential environmental risk of CYN is limited, since the majority of previous studies have mainly focused on the adverse health effects of CYN through contaminated drinking water. The present study reported that CYN at environmentally relevant levels (0.1-100 µg/L) can significantly enhance the conjugative transfer of RP4 plasmid in Escherichia coli genera, wherein application of 10 µg/L of CYN led to maximum fold change of ∼6.5- fold at 16 h of exposure. Meanwhile, evaluation of underlying mechanisms revealed that environmental concentration of CYN exposure could increase oxidative stress in the bacterial cells, resulting in ROS overproduction. In turn, this led to an upregulation of antioxidant enzyme-related genes to avoid ROS attack. Further, inhibition of the synthesis of glutathione (GSH) was also detected, which led to the rapid depletion of GSH in cells and thus triggered the SOS response and promoted the conjugative transfer process. Increase in cell membrane permeability, upregulation of expression of genes related to pilus generation, ATP synthesis, and RP4 gene expression were also observed. These results highlight the potential impact on the spread of antimicrobial resistance in water environments.


Assuntos
Alcaloides , Toxinas Bacterianas , Toxinas de Cianobactérias , Escherichia coli , Glutationa , Plasmídeos , Uracila , Plasmídeos/genética , Glutationa/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Toxinas Bacterianas/toxicidade , Uracila/análogos & derivados , Uracila/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Conjugação Genética , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética
16.
J Agric Food Chem ; 72(14): 8225-8236, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38557068

RESUMO

As a continuous flow investigation of novel pesticides from natural quinolizidine alkaloids, the chemical compositions of the seeds of Sophora alopecuroides were thoroughly researched. Fifteen new aloperine-type alkaloids (1-15) as well as six known aloperine-type alkaloids (16-21) were obtained from the extract of S. alopecuroides. The structures of 1-21 were confirmed via HRESIMS, NMR, UV, IR, ECD calculations, and X-ray diffraction. The antiviral activities of 1-21 against tobacco mosaic virus (TMV) were detected following the improved method of half-leaf. Compared with ningnanmycin (protective: 69.7% and curative: 64.3%), 15 exhibited excellent protective (71.7%) and curative (64.6%) activities against TMV. Further biological studies illustrated that 15 significantly inhibited the transcription of the TMV-CP gene and increased the activities of polyphenol oxidase (PPO), peroxidase (POD), superoxide dismutase (SOD), and phenylalanine ammonia-lyase (PAL). The antifungal activities of 1-21 against Phytophythora capsica, Botrytis cinerea, Alternaria alternata, and Gibberella zeae were screened according to a mycelial inhibition test. Compound 13 displayed excellent antifungal activity against B. cinerea (EC50: 7.38 µg/mL). Moreover, in vitro antifungal mechanism studies displayed that 13 causes accumulation of reactive oxygen species and finally leads to mycelia cell membrane damage and cell death in vitro.


Assuntos
Alcaloides , Quinolizidinas , Sophora , Vírus do Mosaico do Tabaco , Antifúngicos , Sophora/química , Alcaloides/química , Antivirais/farmacologia , Antivirais/química , Sementes/química
17.
Pestic Biochem Physiol ; 200: 105814, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582586

RESUMO

To explore active natural products against tobacco powdery mildew caused by Golovinomyces cichoracearum, an extract from the fermentation of endophytic Aspergillus fumigatus 0338 was investigated. The mechanisms of action for active compounds were also studied in detail. As a result, 14 indole alkaloid derivatives were isolated, with seven being newly discovered (1-7) and the remaining seven previously described (8-14). Notably, compounds 1-3 are rare linearly fused 6/6/5 tricyclic prenylated indole alkaloids, with asperversiamide J being the only known natural product of this kind. The isopentenyl substitutions at the 5-position in compounds 4 and 5 are also rare, with only compounds 1-(5-prenyl-1H-indol-3-yl)-propan-2-one (8) and 1-(6-methoxy-5-prenyl-1H-indol3-yl)-propan-2-one currently available. In addition, compounds 6 and 7 are new framework indole alkaloid derivatives bearing a 6-methyl-1,7-dihydro-2H-azepin-2-one ring. The purified compounds were evaluated for their activity against G. cichoracearum, and the results revealed that compounds 7 and 9 demonstrated obvious anti-G. cichoracearum activities with an inhibition rate of 82.6% and 85.2%, respectively, at a concentration of 250 µg/mL, these rates were better than that of the positive control agent, carbendazim (78.6%). The protective and curative effects of compounds 7 and 9 were also better than that of positive control, at the same concentration. Moreover, the mechanistic study showed that treatment with compound 9 significantly increased the structural tightness of tobacco leaves and directly affect the conidiospores of G. cichoracearum, thereby enhancing resistance. Compounds 7 and 9 could also induce systemic acquired resistance (SAR), directly regulating the expression of defense enzymes, defense genes, and plant semaphorins, which may further contribute to increased plant resistance. Based on the activity experiments and molecular dockings, the indole core structure may be the foundation of these compounds' anti-G. cichoracearum activity. Among them, the indole derivative parent structures of compounds 6, 7, and 9 exhibit strong effects. Moreover, the methoxy substitution in compound 7 can enhance their activity. By isolating and structurally identifying the above indole alkaloids, new candidates for anti-powdery mildew chemical screening were discovered, which could enhance the utilization of N. tabacum-derived fungi in pesticide development.


Assuntos
Alcaloides , Aspergillus fumigatus , Neopreno , Nicotiana , Alcaloides Indólicos/farmacologia , Alcaloides Indólicos/química , Alcaloides/farmacologia
18.
Pathol Res Pract ; 257: 155285, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38653089

RESUMO

Glioblastoma, a highly lethal form of brain cancer, is characterized by its aggressive growth and resistance to conventional treatments, often resulting in limited survival. The response to therapy is notably influenced by various patient-specific genetic factors, underscoring the disease's complexity. Despite the utilization of diverse treatment modalities such as surgery, radiation, and chemotherapy, many patients experience local relapse, emphasizing the critical need for improved therapeutic strategies to effectively target these formidable tumors. Recent years have witnessed a surge in interest in natural products derived from plants, particularly alkaloids, for their potential anticancer effects. Alkaloids have shown promise in cancer chemotherapy by selectively targeting crucial signaling pathways implicated in tumor progression and survival. Specifically, they modulate the NF-κB and MAPK pathways, resulting in reduced tumor growth and altered gene expression across various cancer types. Additionally, alkaloids exhibit the capacity to induce cell cycle arrest, further impeding tumor proliferation in several malignancies. This review aims to delineate recent advances in understanding the pathology of glioblastoma multiforme (GBM) and to explore the potential therapeutic implications of alkaloids in managing this deadly disease. By segregating discussions on GBM pathology from those on alkaloid-based therapies, we provide a structured overview of the current challenges in GBM treatment and the promising opportunities presented by alkaloid-based interventions. Furthermore, we briefly discuss potential future directions in GBM research and therapy beyond alkaloids, including emerging treatment modalities or areas of investigation that hold promise for improving patient outcomes. In conclusion, our efforts offer hope for enhanced outcomes and improved quality of life for GBM patients through alkaloid-based therapies. By integrating insights from pathology and therapeutic perspectives, we underscore the significance of a comprehensive approach in addressing this devastating disease.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/patologia , Glioblastoma/terapia , Glioblastoma/genética , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Alcaloides/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Animais
19.
Antimicrob Agents Chemother ; 68(5): e0161223, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38602413

RESUMO

Mycetoma is a devastating neglected tropical infection of the subcutaneous tissues. It is caused by fungal and bacterial pathogens recognized as eumycetoma and actinomycetoma, respectively. Mycetoma treatment involves diagnosing the causative microorganism as a prerequisite to prescribing a proper medication. Current therapy of fungal eumycetoma causative agents, such as Madurella mycetomatis, consists of long-term antifungal medication with itraconazole followed by surgery, yet with usually unsatisfactory clinical outcomes. Actinomycetoma, on the contrary, usually responds to treatment with co-trimoxazole and amikacin. Therefore, there is a pressing need to discover novel broad-spectrum antimicrobial agents to circumvent the time-consuming and costly diagnosis. Using the resazurin assay, a series of 23 naphthylisoquinoline (NIQ) alkaloids and related naphthoquinones were subjected to in vitro screening against two fungal strains of M. mycetomatis and three bacterial strains of Actinomadura madurae and A. syzygii. Seven NIQs, mostly dimers, showed promising in vitro activities against at least one strain of the mycetoma-causative pathogens, while the naphthoquinones did not show any activity. A synthetic NIQ dimer, 8,8'''-O,O-dimethylmichellamine A (18), inhibited all tested fungal and bacterial strains (IC50 = 2.81-12.07 µg/mL). One of the dimeric NIQs, michellamine B (14), inhibited a strain of M. mycetomatis and significantly enhanced the survival rate of Galleria mellonella larvae infected with M. mycetomatis at concentrations of 1 and 4 µg/mL, without being toxic to the uninfected larvae. As a result, broad-spectrum dimeric NIQs like 14 and 18 with antimicrobial activity are considered hit compounds that could be worth further optimization to develop novel lead antimycetomal agents.


Assuntos
Alcaloides , Antifúngicos , Madurella , Testes de Sensibilidade Microbiana , Micetoma , Micetoma/tratamento farmacológico , Micetoma/microbiologia , Antifúngicos/farmacologia , Animais , Alcaloides/farmacologia , Alcaloides/química , Madurella/efeitos dos fármacos , Isoquinolinas/farmacologia , Actinomadura/efeitos dos fármacos , Naftoquinonas/farmacologia , Larva/microbiologia , Larva/efeitos dos fármacos , Mariposas/microbiologia
20.
Phytochemistry ; 222: 114093, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615927

RESUMO

Nine 3-arylisoquinoline alkaloids including five undescribed ones, hypectumines A-E (1-5), were isolated from the whole herb of Hypecoum erectum L. with the guidance of 1H-NMR. Their structures were established by a combination of 1D, 2D NMR, and HRESIMS spectrometry. Among them, hypectumines A and B possessed rare urea moieties while hypectumines C and D were characterized by 3-(methylamino)propanoic acid scaffolds. Biological assay demonstrated that alkaloids hypectumine B and 2,3-dimethoxy-N-formylcorydamine had anti-inflammatory effects by inhibiting NO production on LPS-induced RAW264.7 cells with IC50 values of 24.4 and 44.2 µM, respectively. Furthermore, hypectumine B could reduce the expression of pro-inflammatory cytokines TNF-α and IL-6, suggesting it might be a potential candidate for treating inflammatory disease.


Assuntos
Alcaloides , Lipopolissacarídeos , Animais , Camundongos , Alcaloides/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Células RAW 264.7 , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Estrutura Molecular , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Isoquinolinas/farmacologia , Isoquinolinas/química , Isoquinolinas/isolamento & purificação , Óxido Nítrico/biossíntese , Óxido Nítrico/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo , Relação Estrutura-Atividade , Interleucina-6/metabolismo , Relação Dose-Resposta a Droga , Espectroscopia de Prótons por Ressonância Magnética
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