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1.
Biomed Res Int ; 2022: 7856305, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35757466

RESUMO

The use of natural products for medicinal purposes is becoming more and more common nowadays, as evidenced by the presence in plants of secondary metabolites with different potentials such as antioxidant and antibacterial properties. We evaluated in this work the antimicrobial activities of the extracts and some isolated compounds from the seeds of Psychotria succulenta Hiern. (Rubiaceae), a Cameroonian medicinal plant traditionally used to cure microbial infections. The ethanol extract was prepared by maceration and extracted with ethyl acetate and n-butanol. The EtOAc (m = 168 g) and n-BuOH (m = 20 g) extracts were further fractionated by silica gel column chromatography to isolation of compounds. Their structures were elucidated by spectroscopic analysis and by comparison with published data. The antibacterial activity of extracts and compounds was assessed by evaluating the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against pathogenic bacteria. Thirteen compounds including four alkaloids (veprisine (1), naucleofficine III (2), vepridimerine B (3), and vepridimerine C (4)), three triterpenes (barbinervic acid (5), 3-O-α-L-rhamnopyranosyl quinovic acid (6), and oleanolic acid (7)), one steroid (ß-sitosterol-3-O-ß-D-glucopyranoside (8)), four phenolic compounds (scopoletin (9), gallic acid (10), quercetin-3-O-ß-D-glucopyranoside (11), and kaempferol 3-O-α-L-rhamnopyranoside-7-O-α-L-rhamnopyranoside (12)), and one iridoid (borreriagenin (13)) were isolated from the EtOAc and n-BuOH extracts. These compounds were identified by 1D and 2D NMR combined analysis as well as by melting point comparison. The EtOH, EtOAc, and n-BuOH extracts exhibited significant antibacterial activities (MIC = 32-128 µg/mL; MBC = 64-256 µg/mL) against Staphylococcus aureus (Gram-positive bacterium), Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumonia (Gram-negative bacteria). Among the isolated compounds, scopoletin (9) showed a moderate activity against Klebsiella pneumoniae with MIC and MBC values of 16 µg/mL and 32 µg/mL, respectively. It appears that, chemotaxonomically, some of the isolated compounds have already been obtained from the genus Psychotria but to the best of our knowledge, this is the first report on the phytochemical investigation of P. succulenta. Although many other studies need to be achieved, our results support the use of P. succulenta in traditional medicine to cure infectious diseases particularly those caused by the tested bacteria.


Assuntos
Psychotria , Rubiaceae , Antibacterianos/química , Bactérias , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Escopoletina
2.
Methods Mol Biol ; 2469: 165-181, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35508838

RESUMO

Cyclotides are small circular peptides carrying an array of interesting biological activities and also showing interesting features for storage and bioavailability. Here, an optimized method to isolate cyclotides from two species of Psychotria, P. brachyceras and P. leiocarpa, that can be integrally performed (to isolate cyclotides) or used in part (to obtain cyclotide-rich extracts), is described. In general this protocol can be applied for cyclotide isolation from any species, taking into account potential minor adaptations for the particularities of specific cases.


Assuntos
Ciclotídeos , Psychotria , Sequência de Aminoácidos , Peptídeos Cíclicos , Proteínas de Plantas/metabolismo , Psychotria/metabolismo
3.
J Ethnopharmacol ; 296: 115220, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-35358624

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Leaves from Psychotria poeppigiana Müll. Arg. (accepted as Palicourea tomentosa (Aubl.) Borhidi), Rubiaceae, has traditionally been used in medicine for treatments of inflammation and pain; Synonymously, Cephaelis elata for the treatment of dementia; However, few scientific studies have been evidence demonstrating this activity. AIM OF THE STUDY: The aim of this study was to investigate the chemical composition of P. poeppigiana essential oil obtained from leaves (EOPP) and its antioxidant, anti-inflammatory and acetylcholinesterase (AChE) activities. Molecular docking simulations were carried out with the main constituents. MATERIALS AND METHODS: EOPP (hydrodistillation) was analysed by gas chromatography-mass spectrometry (GC-MS). The fractionation of EOPP afforded germacrene D and bicyclogermacrene. The antioxidant activity of EOPP was determined by MDA assay. The inflammatory parameters were evaluated using CFA model (with paw edema, mechanical, thermal hyperalgesia, MPO and NAG) in EOPP (30, 100 and 300 mg/kg), germacrene D and bicyclogermacrene (30 mg/kg). The AChE inhibition was evaluated in rat brain structures and molecular docking simulations were carried out using Autodock v.4.3.2. RESULTS: GC-MS analysis identified 19 compounds, and the major compounds were germacrene D (29.38%) and bicyclogermacrene (25.21%). EOPP exhibited high antioxidant capacity (IC50 = 12.78 ± 1.36 µg/mL). All the tested doses of EOPP and both major constituents significantly inhibited cold and mechanical hyperalgesia and significantly blocked the increase in MPO activity 24 h after the CFA injection. There was significant AChE inhibition by EOPP and germacrene D in the cerebral cortex and hippocampus (>50%). Enzyme-ligand molecular modelling showed that the major constituents of EOPP interacted differently with AChE. CONCLUSIONS: The chemical compounds of the essential oil from the leaves of P. poeppigiana is based mainly on terpenes, the sesquiterpenes germacrene D (29.38%) and bicyclogermacrene (25.21%) being the major compounds. EOPP presented antioxidant, anti-inflammatory and anti-acetylcholinesterase (AChE) activities. Besides, enzyme-ligand molecular modelling showed the EOPP may act as an anti-hyperalgesic and AChE inhibitory agent. Taken together, these results might be in accordance with if folk use for pain- and inflammation-related symptoms.


Assuntos
Óleos Voláteis , Psychotria , Acetilcolinesterase , Animais , Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Hiperalgesia/tratamento farmacológico , Inflamação/tratamento farmacológico , Ligantes , Simulação de Acoplamento Molecular , Óleos Voláteis/química , Dor/tratamento farmacológico , Folhas de Planta/química , Ratos
4.
Sci Rep ; 11(1): 22465, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789815

RESUMO

After a century of investigations, the function of the obligate betaproteobacterial endosymbionts accommodated in leaf nodules of tropical Rubiaceae remained enigmatic. We report that the α-D-glucose analogue (+)-streptol, systemically supplied by mature Ca. Burkholderia kirkii nodules to their Psychotria hosts, exhibits potent and selective root growth inhibiting activity. We provide compelling evidence that (+)-streptol specifically affects meristematic root cells transitioning to anisotropic elongation by disrupting cell wall organization in a mechanism of action that is distinct from canonical cellulose biosynthesis inhibitors. We observed no inhibitory or cytotoxic effects on organisms other than seed plants, further suggesting (+)-streptol as a bona fide allelochemical. We propose that the suppression of growth of plant competitors is a major driver of the formation and maintenance of the Psychotria-Burkholderia association. In addition to potential agricultural applications as a herbicidal agent, (+)-streptol might also prove useful to dissect plant cell and organ growth processes.


Assuntos
Alelopatia/fisiologia , Burkholderia/metabolismo , Cicloexanóis/farmacologia , Feromônios/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Folhas de Planta/microbiologia , Psychotria/química , Psychotria/microbiologia , Simbiose/fisiologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Germinação/efeitos dos fármacos , Alface/efeitos dos fármacos , Alface/crescimento & desenvolvimento , Meristema/efeitos dos fármacos , Meristema/crescimento & desenvolvimento , Mostardeira/efeitos dos fármacos , Mostardeira/crescimento & desenvolvimento , Filogenia , Folhas de Planta/metabolismo , Psychotria/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento
5.
Proc Natl Acad Sci U S A ; 118(45)2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34725148

RESUMO

The leaf homogenate of Psychotria insularum is widely used in Samoan traditional medicine to treat inflammation associated with fever, body aches, swellings, wounds, elephantiasis, incontinence, skin infections, vomiting, respiratory infections, and abdominal distress. However, the bioactive components and underlying mechanisms of action are unknown. We used chemical genomic analyses in the model organism Saccharomyces cerevisiae (baker's yeast) to identify and characterize an iron homeostasis mechanism of action in the traditional medicine as an unfractionated entity to emulate its traditional use. Bioactivity-guided fractionation of the homogenate identified two flavonol glycosides, rutin and nicotiflorin, each binding iron in an ion-dependent molecular networking metabolomics analysis. Translating results to mammalian immune cells and traditional application, the iron chelator activity of the P. insularum homogenate or rutin decreased proinflammatory and enhanced anti-inflammatory cytokine responses in immune cells. Together, the synergistic power of combining traditional knowledge with chemical genomics, metabolomics, and bioassay-guided fractionation provided molecular insight into a relatively understudied Samoan traditional medicine and developed methodology to advance ethnobotany.


Assuntos
Anti-Inflamatórios/análise , Flavonoides/isolamento & purificação , Quelantes de Ferro/análise , Fenóis/isolamento & purificação , Psychotria/química , Rutina/isolamento & purificação , Animais , Avaliação Pré-Clínica de Medicamentos , Etnobotânica , Feminino , Genômica , Masculino , Medicina Tradicional , Metabolômica , Camundongos Endogâmicos C57BL , Plantas Medicinais/química , Saccharomyces cerevisiae , Samoa
6.
Arch Virol ; 166(12): 3275-3287, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34536126

RESUMO

Zika virus (ZIKV) is a public health problem due to its association with serious fetal and neurological complications and the lack of antiviral agents and licensed vaccines against this virus. Surveillance studies have alerted about the potential occurrence of a new South American epidemic episode due to the recent circulation of an African ZIKV strain detected in Brazil. Therefore, it is essential to discover antiviral agents, including natural substances, that are capable of neutralizing the action of ZIKV. Several Psychotria species have antimicrobial and anti-inflammatory properties. Thus, a methanol extract and dimethyltryptamine from Psychotria viridis were evaluated for their ability to inhibit ZIKV infection in vitro by measuring the effective concentration that protects 50% of cells and investigating their possible mechanisms of action. The tested samples showed antiviral activity against ZIKV. The extract showed virucidal activity, affecting viral and non-cellular elements, inactivating the virus before infection or when it becomes extracellular after the second cycle of infection. It was also observed that both extract and dimethyltryptamine could inhibit the virus at intracellular stages of the viral cycle. In addition to dimethyltryptamine, it is believed that other compounds also contribute to the promising virucidal effect observed for the methanol extract. To our knowledge, this is the first report of the activity of a methanolic extract and dimethyltryptamine from Psychotria viridis against cellular ZIKV infection. These two samples, extracted from natural sources, are potential candidates for use as antiviral drugs to inhibit ZIKV infections.


Assuntos
Psychotria , Infecção por Zika virus , Zika virus , Antivirais/farmacologia , Antivirais/uso terapêutico , Humanos , Metanol , N,N-Dimetiltriptamina/uso terapêutico , Extratos Vegetais/farmacologia , Infecção por Zika virus/tratamento farmacológico
7.
Metabolomics ; 17(9): 81, 2021 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-34480651

RESUMO

INTRODUCTION: A great variety of bioactive natural products has been reported for different Palicourea and Psychotria species (Rubiaceae). However, few of them as well as few of species of these botanical genera have been evaluated for antiplasmodial activity. OBJECTIVE: To assess the antiplasmodial activity of 24 extracts from Palicourea and Psychotria genera, along with the targeted LC-MS metabolite profiling, as well as identification of the main metabolites in the bioactive extracts. METHODS: Twenty four ethanol and acid-base extracts from Palicourea and Psychotria genera collected in the Amazonia and Atlantic Forest, Brazil, were evaluated against chloroquine-resistant Plasmodium falciparum W2 strain by PfLDH. The metabolite profiling and putative identification of metabolites from bioactive extracts were determined by LC-DAD-ESI-MS and LC-HRMS, respectively. RESULTS: The ethanol extracts disclosed low antiplasmodial activity (% GI < 50%). High antiplasmodial effect was observed for the acid-base extracts from Psychotria apoda and Psychotria colorata with 100% inhibition of parasite growth inhibition. Fragment ions related to pyrrolidinoindoline alkaloids were observed by LC-DAD-ESI-MS mainly in the most bioactive extracts. The results of the in vitro screening associated with the LC-DAD-ESI-MS and LC-HRMSn data allowed to predict, for the first time, the pyrrolidinoindoline alkaloids as possible antiplasmodial representing, then, new potential natural antimalarial hits. In addition, other metabolite classes such as flavanones, lignans and chalcones were also putatively identified in the bioactive extracts of Psychotria apoda, Psychotria capitata, and Psychotria poeppigiana. CONCLUSION: The present results point to Palicourea and Psychotria species as sources of new antimalarial hits.


Assuntos
Alcaloides , Antimaláricos , Produtos Biológicos , Psychotria , Rubiaceae , Alcaloides/farmacologia , Antimaláricos/farmacologia , Brasil , Cromatografia Líquida , Ecossistema , Etanol , Florestas , Extratos Vegetais/farmacologia , Folhas de Planta , Espectrometria de Massas em Tandem
8.
Metab Brain Dis ; 36(7): 2015-2027, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34460047

RESUMO

A substantial number of epileptic patients are resistant to the current medication thus necessitating the search for alternative therapies for intractable forms of the disease. Previous studies demonstrated the acute anticonvulsant properties of the methanol extract of the stem bark of Psychotria camptopus (MEPC) in rats. This study investigated the effects of MEPC on pentylenetetrazole-kindled Wistar rats. Kindling was induced by intraperitoneal injection of pentylenetetrazole (37.5 mg/kg) on every alternate day, 1 h after each daily oral pretreatment of rats (8 ≤ n ≤ 10) with MEPC (40, 80 and 120 mg/kg), vehicle or diazepam (3 mg/kg) for 43 days. The kindling development was monitored based on seizure episodes and severity. Rats' brains were collected on day 43 for the determination of oxidative stress parameters. The histomorphological features and neuronal cell viability of the prefrontal cortex (PFC) and hippocampus were also assessed using H&E and Cresyl violet stains. Chronic administration of pentylenetetrazole time-dependently decreased the latency to myoclonic and generalized seizures, and increased seizure scores and the number of kindled rats. MEPC and diazepam significantly increased the latencies to myoclonic jerks and generalized tonic-clonic seizures. These substances also reduced seizure score and the number of rats with PTZ-kindling. MEPC improved glutathione status and decreased lipid peroxidation in the brains of kindled rats. MEPC also exhibited neuroprotection against pentylenetetrazole-induced hippocampal and PFC neuronal damages. These results suggest that P. camptopus has antiepileptogenic activity, which might be related to the augmentation of antioxidant and neuroprotective defense mechanisms, and further confirm its usefulness in the management of epilepsy.


Assuntos
Excitação Neurológica , Fármacos Neuroprotetores , Psychotria , Rubiaceae , Animais , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Humanos , Masculino , Metanol/farmacologia , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Pentilenotetrazol/farmacologia , Casca de Planta , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar
9.
J Ethnopharmacol ; 272: 113955, 2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-33610704

RESUMO

ETHNOPHARMACOLOGY RELEVANCE: The decoction from the stem bark of Psychotria camptopus (Rubiaceae) is used in the Cameroonian pharmacopoeia to treat neurological pathologies including epilepsy. AIM: The present work was undertaken to study the anticonvulsant properties of the aqueous (AE) and methanol (ME) extracts from the stem bark of P. camptopus in acute models of epileptic seizures in Wistar rats. METHOD: AE and ME were obtained by decoction and maceration of the stem bark powder in water and methanol, respectively. They were tested orally at the doses of 40, 80 and 120 mg/kg, on the latency of onset and duration of epileptic seizures induced by pentylene tetrazole (PTZ, 70 mg/kg, i.p.). The kinetic effect of both extracts at 120 mg/kg was evaluated. Their effects on diazepam (50 mg/kg) induced sleep and strychnine (STR, 2.5 mg/kg, i.p.) induced seizures were determined. ME was further tested on picrotoxin (PIC, 7.5 mg/kg, i.p.) and thiosemicarbazide (TSC, 50 mg/kg, i.p.) induced seizure models. The phytochemical composition of ME was assessed using LC-MS method, as well as its acute toxicity. RESULTS: AE and ME significantly (p < 0.001) reduced the duration of seizures in both PTZ and STR models. Their maximal effect was observed at 1 h after administration, though their effect at 120 mg/kg was maintained (p < 0.05) up to 24 h post-treatment. Both extracts significantly (p < 0.01) reduced sleep duration. ME significantly (p < 0.001) increased the latency of rat death on PIC-induced convulsions. In TSC rats, ME significantly (p < 0.001) delayed the latency to the first convulsion, and decreased the duration and frequency of convulsions. ME showed no acute toxicity while its phytochemical screening revealed the presence of two flavonoids (Rutin and Butin), two triterpenoid saponins (Psycotrianoside B and Bauerenone) and four alkaloids (10-Hydroxy-antirhine, 10-hydroxy-iso-deppeaninol, Emetine and Hodkinsine). In conclusion, AE and ME from the stem bark of P. camptopus have comparable anticonvulsant properties. The effect of ME is likely due to the presence of flavonoids and alkaloid and the activation of GABA pathway. These results further justify and support the use of P. camptopus in traditional medicine for the treatment of epilepsy.


Assuntos
Anticonvulsivantes/farmacologia , Epilepsia/tratamento farmacológico , Extratos Vegetais/farmacologia , Psychotria/química , Convulsões/tratamento farmacológico , Animais , Anticonvulsivantes/uso terapêutico , Anticonvulsivantes/toxicidade , Comportamento Animal/efeitos dos fármacos , Diazepam/farmacologia , Diazepam/uso terapêutico , Modelos Animais de Doenças , Epilepsia/induzido quimicamente , Metanol/química , Camundongos , Pentilenotetrazol/toxicidade , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Picrotoxina/toxicidade , Casca de Planta/química , Extratos Vegetais/uso terapêutico , Extratos Vegetais/toxicidade , Caules de Planta/química , Ratos Wistar , Convulsões/induzido quimicamente , Semicarbazidas/toxicidade , Sono/efeitos dos fármacos , Latência do Sono/efeitos dos fármacos , Estricnina/toxicidade , Água/química
10.
Nat Prod Res ; 35(23): 5036-5041, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32400194

RESUMO

A new hexenoic acid glycoside (1) together with known compounds, flavonol glycosides (2-4), iridoid glycoside (5), megastigmane glycoside (6), and amino acid (7) were isolated from the leaves of P. luzoniensis by resin column chromatography and preparative HPLC. Their structures were determined based on spectroscopic analysis, including HRFABMS and NMR (1H and 13C, 1H-1H COSY, HMQC, and HMBC) data. All compounds tested for cytotoxicity were active (IC50 < 50 µM) with IC50 values ranging from 1.97 to 32.85 µM against human colon adenocarcinoma cell line, compared to etoposide (IC50 1.19 µM).


Assuntos
Antineoplásicos , Psychotria , Flavonóis , Glicosídeos/farmacologia , Humanos , Estrutura Molecular , Folhas de Planta
11.
Molecules ; 25(24)2020 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-33322801

RESUMO

Psychotria malayana Jack has traditionally been used to treat diabetes. Despite its potential, the scientific proof in relation to this plant is still lacking. Thus, the present study aimed to investigate the α-glucosidase inhibitors in P.malayana leaf extracts using a metabolomics approach and to elucidate the ligand-protein interactions through in silico techniques. The plant leaves were extracted with methanol and water at five various ratios (100, 75, 50, 25 and 0% v/v; water-methanol). Each extract was tested for α-glucosidase inhibition, followed by analysis using liquid chromatography tandem to mass spectrometry. The data were further subjected to multivariate data analysis by means of an orthogonal partial least square in order to correlate the chemical profile and the bioactivity. The loading plots revealed that the m/z signals correspond to the activity of α-glucosidase inhibitors, which led to the identification of three putative bioactive compounds, namely 5'-hydroxymethyl-1'-(1, 2, 3, 9-tetrahydro-pyrrolo (2, 1-b) quinazolin-1-yl)-heptan-1'-one (1), α-terpinyl-ß-glucoside (2), and machaeridiol-A (3). Molecular docking of the identified inhibitors was performed using Auto Dock Vina software against the crystal structure of Saccharomyces cerevisiae isomaltase (Protein Data Bank code: 3A4A). Four hydrogen bonds were detected in the docked complex, involving several residues, namely ASP352, ARG213, ARG442, GLU277, GLN279, HIE280, and GLU411. Compound 1, 2, and 3 showed binding affinity values of -8.3, -7.6, and -10.0 kcal/mol, respectively, which indicate the good binding ability of the compounds towards the enzyme when compared to that of quercetin, a known α-glucosidase inhibitor. The three identified compounds that showed potential binding affinity towards the enzymatic protein in molecular docking interactions could be the bioactive compounds associated with the traditional use of this plant.


Assuntos
Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Extratos Vegetais/farmacologia , Psychotria/química , alfa-Glucosidases/metabolismo , Simulação por Computador , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Metabolômica , Simulação de Acoplamento Molecular , Estrutura Molecular , Análise Multivariada , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química
12.
Molecules ; 25(18)2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32932994

RESUMO

The plant Psychotria malayana Jack belongs to the Rubiaceae family and is known in Malaysia as "meroyan sakat/salung". A rapid analytical technique to facilitate the evaluation of the P. malayana leaves' quality has not been well-established yet. This work aimed therefore to develop a validated analytical technique in order to predict the alpha-glucosidase inhibitory action (AGI) of P. malayana leaves, applying a Fourier Transform Infrared Spectroscopy (FTIR) fingerprint and utilizing an orthogonal partial least square (OPLS). The dried leaf extracts were prepared by sonication of different ratios of methanol-water solvent (0, 25, 50, 75, and 100% v/v) prior to the assessment of alpha-glucosidase inhibition (AGI) and the following infrared spectroscopy. The correlation between the biological activity and the spectral data was evaluated using multivariate data analysis (MVDA). The 100% methanol extract possessed the highest inhibitory activity against the alpha-glucosidase (IC50 2.83 ± 0.32 µg/mL). Different bioactive functional groups, including hydroxyl (O-H), alkenyl (C=C), methylene (C-H), carbonyl (C=O), and secondary amine (N-H) groups, were detected by the multivariate analysis. These functional groups actively induced the alpha-glucosidase inhibition effect. This finding demonstrated the spectrum profile of the FTIR for the natural herb P. malayana Jack, further confirming its medicinal value. The developed validated model can be used to predict the AGI of P. malayana, which will be useful as a tool in the plant's quality control.


Assuntos
Inibidores Enzimáticos/química , Inibidores de Glicosídeo Hidrolases/química , Extratos Vegetais/química , Psychotria/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Inibidores Enzimáticos/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Concentração Inibidora 50 , Análise dos Mínimos Quadrados , Análise Multivariada , Folhas de Planta/química , Solventes , alfa-Glucosidases
13.
J Am Chem Soc ; 142(27): 11685-11690, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32520547

RESUMO

Bis(cyclotryptamine) alkaloids have been popular topics of study for many decades. Five possible scaffolds for bis(cyclotryptamine) alkaloids were originally postulated in the 1950s, but only four of these scaffolds have been observed in natural products to date. We describe synthetic access to the elusive fifth scaffold, the piperidinoindoline, through syntheses of compounds now termed "dihydropsychotriadine" and "psychotriadine". The latter of these compounds was subsequently identified in extracts of the flower Psychotria colorata. Our synthetic route features a stereospecific solid-state photodecarbonylation reaction to introduce the key vicinal quaternary stereocenters.


Assuntos
Alcaloides/síntese química , Produtos Biológicos/síntese química , Indóis/química , Piperidinas/química , Triptaminas/síntese química , Alcaloides/química , Produtos Biológicos/química , Flores/química , Estrutura Molecular , Psychotria/química , Estereoisomerismo , Triptaminas/química
14.
Sci Total Environ ; 724: 138183, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32408446

RESUMO

To assess the effects of nitrogen deposition on forest plants, researchers have conducted many nitrogen-addition experiments. Most of these experiments, however, failed to fully simulate atmospheric nitrogen deposition because they failed to assess interception of nitrogen deposition by the forest canopy. Here, we used transcriptomics, proteomics, and metabolomics to compare the effects of understory nitrogen addition (UAN), canopy nitrogen addition (CAN), and a control (no nitrogen addition) on carbon and nitrogen metabolism in leaves of Psychotria rubra, a dominant subtropical understory plant species in evergreen broad-leaved forests in South China. We first established a reference P. rubra transcriptome via RNA-seq and obtained a total of 93,986 unigenes from de novo assembly. Next, we quantitatively investigated the proteome and metabolome in leaves, and identified 4021 proteins and 562 metabolites. Under the CAN treatment and relative to the control, 36 genes were up-regulated and 23 were down-regulated, and we identified 46 up-regulated proteins and 49 down-regulated proteins. Under the UAN treatment and relative to the control, 1525 genes were up-regulated and 224 genes down-regulated, and we identified 35 up-regulated proteins and 71 down-regulated proteins. These differentially expressed genes and proteins were related to photosynthesis, amino acid metabolism, and flavonoid biosynthesis. Accordingly, 15 differentially accumulated metabolites in response to CAN and 20 in response to UAN were found; these differentially accumulated metabolites included 4 amino acids and 3 flavonoids. Taken together, our results show that the UAN treatment had a greater effect on photosynthesis, amino acid metabolism, and flavonoid biosynthesis than the CAN treatment. Most importantly, the results indicate that understory application of nitrogen in experiments may incorrectly estimate the effects of nitrogen deposition on nitrogen and carbon utilization by P. rubra and perhaps by other understory woody plants in the evergreen broad-leaved forests in South China as well.


Assuntos
Nitrogênio , Psychotria , Carbono , China , Florestas , Árvores
15.
J Ethnopharmacol ; 255: 112743, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32171895

RESUMO

ETHNOPHARMACOLOGY RELEVANCE: Ayahuasca is a tea produced through decoction of Amazonian plants. It has been used for centuries by indigenous people of South America. The beverage is considered to be an ethnomedicine, and it is traditionally used for the treatment of a wide range of diseases, including neurological illness. Besides, some scientific evidence suggests it may be applicable to Parkinson's disease (PD) treatment. Thus, Ayahuasca deserves in depth studies to clarify its potential role in this disease. AIM OF THE STUDY: This study aimed to use an untargeted metabolomics approach to evaluate the neuroprotective potential of the Ayahuasca beverage, the extracts from its matrix plants (Banisteriopsis caapi and Psychotria viridis), its fractions and its main alkaloids on the viability of SH-SY5Y neuroblastoma cells in an in vitro PD model. MATERIAL AND METHODS: The cytotoxicity of Ayahuasca, crude extracts, and fractions of B. caapi and P. viridis, as well as neuroprotection promoted by these samples in a 6-hydroxydopamine (6-OHDA)-induced neurodegeneration model, were evaluated by the MTT assay at two time-points: 48 h (T1) and 72 h (T2). The main alkaloids from Ayahuasca matrix plants, harmine (HRE) and N,N-dimethyltryptamine (DMT), were also isolated and evaluated. An untargeted metabolomics approach was developed to explore the chemical composition of samples with neuroprotective activity. Ultra-Performance Liquid Chromatography coupled to Electrospray Ionisation and Time-of-Flight (UPLC-ESI-TOF) metabolome data was treated and further analysed using multivariate statistical analyses (MSA): principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). The metabolites were dereplicated using the Dictionary of Natural Products and an in house database. The main alkaloids were also quantified by UPLC-MS/MS. RESULTS: The samples did not cause cytotoxicity in vitro and three of samples intensely increased cell viability at T1. The crude extracts, alkaloid fractions and HRE demonstrated remarkable neuroprotective effect at T2 while the hydroalcoholic fractions demonstrated this neuroprotective effect at T1 and T2. Several compounds from different classes, such as ß-carbolines and monoterpene indole alkaloids (MIAs) were revealed correlated with this property by MSA. Additionally, a total of 2419 compounds were detected in both ionisation modes. HRE showed potent neuroprotective action at 72 h, but it was not among the metabolites positively correlated with the most efficacious neuroprotective profile at either time (T1 and T2). Furthermore, DMT was statistically important to differentiate the dataset (VIP value > 1), although it did not exhibit sufficient neuroprotective activity by in vitro assay, neither a positive correlation with T1 and T2 neuroprotective profile, which corroborated the MSA results. CONCLUSION: The lower doses of the active samples stimulated neuronal cell proliferation and/or displayed the most efficacious neuroprotection profile, namely by preventing neuronal damage and improving cell viability against 6-OHDA-induced toxicity. Intriguingly, the hydroalcoholic fractions exhibited enhanced neuroprotective effects when compared to other samples and isolated alkaloids. This finding corroborates the significance of a holistic approach. The results demonstrate that Ayahuasca and its base plants have potential applicability for PD treatment and to prevent its progression differently from current drugs to treat PD.


Assuntos
Antiparkinsonianos/farmacologia , Banisteriopsis/química , Metabolômica , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Psychotria/química , Antiparkinsonianos/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Etnofarmacologia , Humanos , Análise dos Mínimos Quadrados , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/isolamento & purificação , Oxidopamina/toxicidade , Extratos Vegetais/isolamento & purificação , Polissacarídeos , Análise de Componente Principal , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
16.
J Nat Prod ; 83(4): 852-863, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32150413

RESUMO

Phytochemical investigation of the alkaloid extract of the aerial parts of Psychotria nemorosa led to the isolation and characterization of 10 azepine-indole alkaloids, i.e., cimitrypazepine (1), fargesine (2), nemorosines A (3), and B (12), nemorosinosides A-F (4-9), as well as two ß-carboline derivatives, 10-hydroxyisodolichantoside (10) and 10-hydroxydolichantoside (11), an isoxazole alkaloid, nemorosinoside G (13), serotonin (14), bufotenine (15), and (S)-gentianol (16). Compounds 3-13 have not yet been described. These compounds were isolated by semipreparative HPLC, and their structures were determined by means of HRMS, NMR, and ECD measurements. In addition, the monoamine oxidase-A (MAO-A), MAO-B, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) inhibitory activities were evaluated. Alkaloids 1-3 inhibited the MAO-A activity with IC50 values of 1.4, 1.4, and 0.9 µM, respectively.


Assuntos
Azepinas/química , Azepinas/farmacologia , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacologia , Psychotria/química , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/farmacologia , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Espectrometria de Massas por Ionização por Electrospray
17.
Nat Prod Res ; 34(14): 2095-2100, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30777444

RESUMO

In clinical, Psychotria serpens L. was often substitute for Caulis trachelospermi to treat cancer in China. Meanwhile, EtOAc and n-BuOH fractions of MeOH extract of P. serpens L. show power activity against H460, HepG2, Hela, and PC9/GR cell lines, and no toxic effects against normal 16HBE cell lines. In our ongoing search for bioactive novel compounds from Chinese material medica, one new type of glycosylsphingolipids Psychotramide (1a-1c) were isolated from P. serpens L., and their structures were identified through spectroscopic techniques including NMR (1D and 2D) and MS (LC-MS, and GC-MS).


Assuntos
Glicoesfingolipídeos/isolamento & purificação , Psychotria/química , Linhagem Celular , China , Cromatografia Gasosa-Espectrometria de Massas , Glicoesfingolipídeos/química , Glicoesfingolipídeos/farmacologia , Humanos , Medicina Tradicional Chinesa , Estrutura Molecular , Análise Espectral
18.
Eat Weight Disord ; 25(2): 437-444, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30474794

RESUMO

PURPOSE: Ayahuasca is a traditional Amazonian medicine that is currently being researched for its potential in treating a variety of mental disorders. This article reports on exploratory qualitative research relating to participant experiences with ceremonial ayahuasca drinking and conventional treatment for eating disorders (EDs). It also explores the potential for ayahuasca as an adjunctive ED treatment. METHODS: Thirteen individuals previously diagnosed with an ED participated in a semi-structured interview contrasting their experiences with conventional ED treatment with experiences from ceremonial ayahuasca. The interviews were analyzed using thematic analysis. RESULTS: Participant reports were organized with key themes including that ayahuasca: led to rapid reductions in ED thoughts and symptoms; allowed for the healing of the perceived root of the ED; helped to process painful feelings and memories; supported the internalization of greater self-love and self-acceptance; and catalyzed spiritual elements of healing. CONCLUSIONS: The results suggest that ayahuasca may have potential as a valuable therapeutic tool, and further research-including carefully controlled clinical trials-is warranted. LEVEL OF EVIDENCE: Level V, qualitative descriptive study.


Assuntos
Banisteriopsis , Comportamento Ritualístico , Transtornos da Alimentação e da Ingestão de Alimentos/terapia , Psychotria , Adulto , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Adulto Jovem
19.
Braz. J. Pharm. Sci. (Online) ; 56: e18158, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132035

RESUMO

Psychotria fractistipula L.B.Sm, R.M. Klein & Delprete (Rubiaceae) is found in the existing Atlantic Forest in the South of Brazil, in the Paraná and Santa Catarina States. The members of Rubiaceae are characterized chemically by the presence of alkaloids, some pharmacological properties of which include antifungal, antibacterial, analgesic, antioxidant, antimutagenic, and antiviral activities. In this study, we report the results of anatomical, morphological, and histochemical analyses of the leaves and stems of the Rubiaceae family member, P. fractistipula. The anatomical analysis involved of light microscopy and scanning electron microscopy. Morpho-anatomical and histochemical characterization were made using standard methodology. The isolated compounds were identified by Nuclear Magnetic Resonance spectroscopic analysis. The following structures are highlighted as the distinctive features of the species: presence of petiolate leaves and a petiole base, leaf blade with smooth cuticle on both surfaces, paracytic stomata, and, dorsiventral mesophyll and presence of trichomes on the leaves and stems. Phytosteroids, identified as β-sitosterol and campesterol, were observed in the hexane fraction of the stem. Future studies should focus on the isolation of other fractions of interest and their characterization through specific biological and cytotoxicity assays.


Assuntos
Rubiaceae/classificação , Psychotria/classificação , Compostos Fitoquímicos/efeitos adversos , Microscopia Eletrônica de Varredura/instrumentação , Espectroscopia de Ressonância Magnética/métodos , Microscopia Eletrônica de Transmissão e Varredura/métodos , Relatório de Pesquisa , Tricomas/anatomia & histologia , Analgésicos/farmacologia , Antioxidantes/farmacologia
20.
Am J Bot ; 106(10): 1377-1385, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31553490

RESUMO

PREMISE: Hyperaccumulation of heavy metals in plants has never been documented from Central America or Mexico. Psychotria grandis, P. costivenia, and P. glomerata (Rubiaceae) have been reported to hyperaccumulate nickel in the Greater Antilles, but they also occur widely across the neotropics. The goals of this research were to investigate the geographic distribution of hyperaccumulation in these species and explore the phylogenetic distribution of hyperaccumulation in this clade by testing related species. METHODS: Portable x-ray fluorescence (XRF) spectroscopy was used to analyze 565 specimens representing eight species of Psychotria from the Missouri Botanical Garden herbarium. RESULTS: Nickel hyperaccumulation was found in specimens of Psychotria costivenia ranging from Mexico to Costa Rica and in specimens of P. grandis from Guatemala to Ecuador and Venezuela. Among related species, nickel hyperaccumulation is reported for the first time in P. lorenciana and P. papantlensis, but no evidence of hyperaccumulation was found in P. clivorum, P. flava, or P. pleuropoda. Previous reports of hyperaccumulation in P. glomerata appear to be erroneous, resulting from taxonomic synonymy and specimen misidentification. CONCLUSIONS: Hyperaccumulation of nickel by Psychotria is now known to occur widely from southern Mexico through Central America to northwestern South America, including some areas not known to have ultramafic soils. Novel aspects of this research include the successful prediction of new hyperaccumulator species based on molecular phylogeny, use of XRF technology to nondestructively obtain elemental data from herbarium specimens, and documentation of previously unknown areas of ultramafic or nickel-rich soil based on such data.


Assuntos
Psychotria , América Central , Costa Rica , México , Níquel , Filogenia , América do Sul
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