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1.
An Acad Bras Cienc ; 96(1): e20230456, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511745

RESUMO

Vismia japurensis Reichardt is a plant of ecological and chemical importance from which a variety of bioactive substances have been isolated. The current study aimed to establish in vitro cultures of this species as a source of secondary metabolites. Appropriate decontamination treatments and germination tests were performed and, after in vitro culture establishment, the propagated plants were multiplied in a sterile environment to increase the biomass of available experimental material. Seeds showed low contamination and a high germination percentage on Woody Plant Medium (WPM) supplemented with gibberellic acid (both at concentrations of 5 and 10 mg/L). V. japurensis nodal segments rapidly regenerated when first grown in WPM and then transplanted to Murashige and Skoog medium (MS). After 60 days in MS medium, the propagated plants were removed, lyophilized, and extracted with hexane and methanol. The hexane extract was fractionated via open column chromatography, and the substance isolated was purified by high performance liquid chromatography. Structural determination of the isolated substance was carried out using one and two-dimensional nuclear magnetic resonance and mass spectrometry. The isolated substance was identified as 1,8,10-trihydroxy-3,10-dimethyl-9(10H)-anthracenone, which, based on the conducted literature search, is reported for the first time.


Assuntos
Antronas , Hexanos , Plantas , Sementes
2.
J Fungi (Basel) ; 9(8)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37623634

RESUMO

The endophytic fungal community of the Amazonian medicinal plant Arrabidaea chica (Bignoniaceae) was evaluated based on the hypothesis that microbial communities associated with plant species in the Amazon region may produce metabolites with interesting bioactive properties. Therefore, the antimicrobial and antioxidant activities of the fungal extracts were investigated. A total of 107 endophytic fungi were grown in liquid medium and the metabolites were extracted with ethyl acetate. In the screening of fungal extracts for antimicrobial activity, the fungus identified as Botryosphaeria mamane CF2-13 was the most promising, with activity against E. coli, S. epidermidis, P. mirabilis, B. subtilis, S. marcescens, K. pneumoniae, S. enterica, A. brasiliensis, C. albicans, C. tropicalis and, especially, against S. aureus and C. parapsilosis (MIC = 0.312 mg/mL). Screening for antioxidant potential using the DPPH elimination assay showed that the Colletotrichum sp. CG1-7 endophyte extract exhibited potential activity with an EC50 of 11 µg/mL, which is equivalent to quercetin (8 µg/mL). The FRAP method confirmed the antioxidant potential of the fungal extracts. The presence of phenolic compounds and flavonoids in the active extracts was confirmed using TLC. These results indicate that two of the fungi isolated from A. chica exhibit significant antimicrobial and antioxidant potential.

3.
Drug Alcohol Depend ; 249: 109950, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37301068

RESUMO

BACKGROUND AND AIMS: Identifying modifiable neuropsychological factors associated with more severe CUD could improve CUD treatment. Impairments in processing of non-drug rewards may be one such factor. This study assessed the relationship between reward functioning and cocaine use severity using multi-modal measures of three distinct reward functions: consummatory reward (pleasure or "liking"); motivational reward ("wanting") and reward learning. METHODS: Fifty-three adults with at least moderate CUD completed self-report and behavioral measures of consummatory reward, motivational reward and reward learning, and a composite cocaine use severity measure including quantity, frequency and life impacts of cocaine use. We conducted parallel Frequentist and Bayesian multiple regressions with measures of reward functioning as predictors of cocaine use severity. RESULTS: Less self-reported ability to experience pleasure, a hypothesized measure of consummatory reward, significantly predicted greater severity after adjustment for covariates and multiple hypothesis testing, ß = 0.39, t(38) = 2.86, p = 0.007. Bayesian analyses confirmed a highly likely association between severity and ability to experience pleasure, and provided moderate evidence for associations with willingness to exert effort and reward learning. CONCLUSIONS: Our results suggest that less experience of subjective pleasure is related to greater cocaine use severity. This cross-sectional study cannot establish whether differences in consummatory reward are pre-existing, a result of CUD, or both. However, these results suggest interventions focused on increasing subjective pleasure, such as mindful "savoring", should be investigated for CUD.


Assuntos
Transtornos Relacionados ao Uso de Cocaína , Cocaína , Adulto , Humanos , Estudos Transversais , Teorema de Bayes , Motivação , Prazer , Recompensa , Cocaína/efeitos adversos , Anedonia
5.
PLoS One ; 17(10): e0275027, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36197897

RESUMO

Many mental health disorders are characterized by an impaired ability, or willingness, to exert effort to obtain rewards. This impairment is modeled in effort-based decision tasks, and neuropharmacological studies implicate dopamine in this process. However, other transmitter systems such as opioidergic and cholinergic systems have received less attention. Here, in two separate studies we tested the acute effects of naltrexone and nicotine on effort-based decision-making in healthy adults. In Study 1, we compared naltrexone (50mg and 25mg) to placebo, and in Study 2, a pilot study, we compared nicotine (7mg) to placebo. In both studies, participants completed the Effort Expenditure for Rewards Task (EEfRT), which measured effort-based decision-making related to monetary rewards. Although subjects expended greater effort for larger reward magnitude and when there was a higher probability of receiving the reward, neither naltrexone nor nicotine affected willingness to exert effort for monetary rewards. Although the drugs produced significant and typical drug effects on measures of mood and behavior, they did not alter effort-based decision-making. This has implications both for the clinical use of these drugs, as well as for understanding the neuropharmacology of effort-related behavior.


Assuntos
Naltrexona , Nicotina , Adulto , Colinérgicos/farmacologia , Tomada de Decisões , Dopamina/farmacologia , Humanos , Motivação , Naltrexona/farmacologia , Nicotina/farmacologia , Projetos Piloto , Recompensa
6.
Int J Microbiol ; 2022: 4010018, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35620355

RESUMO

The antimicrobial potential of Aspergillus sp., isolated from the Amazon biome, which is stored at the Amazon Fungi Collection-CFAM at ILMD/FIOCRUZ, was evaluated. The fungal culture was cultivated in yeast extract agar and sucrose (YES) for cold extraction of the biocompounds in ethyl acetate at 28 °C for 7 days in a BOD type incubator. The obtained extract was evaluated for its antimicrobial activity against Candida albicans and Gram-positive and negative bacteria by the "cup plate" method and the determination of the minimum inhibitory concentration (MIC) by the broth microdilution method. The extract was subjected to thin layer chromatography (TLC) and fractionated by open and semipreparative column chromatography. The fractions of interest had their chemical constituents elucidated by nuclear magnetic resonance and mass spectrometry. The elucidated molecule was evaluated for cytotoxicity against the human fibroblast strain (MRC5). The extract presented inhibitory activity against both Gram-positive and negative bacteria, with the range of inhibition halos from 5.3 to 14 mm in diameter and an MIC ranging from 500 to 15.6 µg/mL. Seventy-one fractions were collected and TLC analysis suggested the presence of substances with double bond groups: coumarins, flavonoids, phenolic, alkaloids, and terpenes. NMR and MS analyses demonstrated that the isolated molecule was kojic acid. The results of the cytotoxicity test showed that MRC5 cells presented viability at concentrations from 500 to 7.81 µg/mL. The kojic acid molecule of Aspergillus sp., with antibacterial activity and moderate toxicity at the concentrations tested, is a promising prototype of an alternative active principle of an antimicrobial drug.

7.
Psychopharmacology (Berl) ; 238(10): 2815-2826, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34137904

RESUMO

RATIONALE: Misuse of dextroamphetamine occurs in work and recreational contexts. While acute drug effects broadly predict abuse liability, few studies have considered the relationship between acute effects and context. OBJECTIVES: This study examined how individual differences in acute effects of dextroamphetamine relate to desire to take dextroamphetamine again in different contexts. METHODS: This secondary analysis used data from healthy adults with no history of moderate-to-severe substance use disorder, who received oral doses of placebo and dextroamphetamine (10 and 20 mg) over 3 sessions under double-blind, randomized conditions. Subjects rated subjective effects and completed reward-related behavioral tasks. Subjects rated their desire to take dextroamphetamine again in hypothetical work and recreational contexts. Multilevel models examined within-subjects change scores (10 mg-placebo; 20 mg-placebo) to determine how subjective effects and behavioral outcomes predicted desire to take dextroamphetamine again for work versus recreation. RESULTS: Subjects reported more desire to take 20 mg dextroamphetamine again for work than for recreation. At 20 mg, there was an interaction between context and liking/wanting, such that liking/wanting predicted desire to use dextroamphetamine for work only. There was also an interaction at 20 mg between context and psychomotor speed, such that psychomotor speed predicted interest in using dextroamphetamine for recreation only. CONCLUSIONS: We found that positive subjective effects predicted desire to use dextroamphetamine again for work, while increased motor effects predicted desire to use dextroamphetamine recreationally. Hedonic effects may be perceived as advantageous when working, while increased physical energy may be preferred during recreation, suggesting that context of intended use is important when examining abuse liability.


Assuntos
Estimulantes do Sistema Nervoso Central , Preparações Farmacêuticas , Transtornos Relacionados ao Uso de Substâncias , Adulto , Estimulantes do Sistema Nervoso Central/farmacologia , Dextroanfetamina/farmacologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Humanos , Recreação , Recompensa
8.
Neuropsychopharmacology ; 46(6): 1078-1085, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32722661

RESUMO

Effort-related decision-making and reward learning are both dopamine-dependent, but preclinical research suggests they depend on different dopamine signaling dynamics. Therefore, the same dose of a dopaminergic medication could have differential effects on effort for reward vs. reward learning. However, no study has tested how effort and reward learning respond to the same dopaminergic medication within subjects. The current study aimed to test the effect of therapeutic doses of d-amphetamine on effort for reward and reward learning in the same healthy volunteers. Participants (n = 30) completed the Effort Expenditure for Reward Task (EEfRT) measure of effort-related decision-making, and the Probabilistic Reward Task (PRT) measure of reward learning, under placebo and two doses of d-amphetamine (10 mg, and 20 mg). Secondarily, we examined whether the individual characteristics of baseline working memory and willingness to exert effort for reward moderated the effects of d-amphetamine. d-Amphetamine increased willingness to exert effort, particularly at low to intermediate expected values of reward. Computational modeling analyses suggested this was due to decreased effort discounting rather than probability discounting or decision consistency. Both baseline effort and working memory emerged as moderators of this effect, such that d-amphetamine increased effort more in individuals with lower working memory and lower baseline effort, also primarily at low to intermediate expected values of reward. In contrast, d-amphetamine had no significant effect on reward learning. These results have implications for treatment of neuropsychiatric disorders, which may be characterized by multiple underlying reward dysfunctions.


Assuntos
Dextroanfetamina , Motivação , Tomada de Decisões , Dextroanfetamina/farmacologia , Humanos , Reforço Psicológico , Recompensa
9.
PLoS One ; 15(12): e0243654, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33290419

RESUMO

Extracts made from the skin of dead Lithodytes lineatus frog individuals with the application of the benzocaine-based anesthetic gel, introduced into the oral cavity, were analyzed by 1H Nuclear Magnetic Resonance to investigate whether the application of this product (oral) can make studies that use extracts from the skins of these animals unfeasible. For comparison, we used skins of another species of anuran following the same death protocol. No trace of the benzocaine substance was found in the 1H-NMR spectra of the skin extracts from any of the tested anuran species. Still, using the hierarchical clustering model, it was possible to observe the formation of well-defined groups between the skin extracts of anurans and the anesthetic used to kill these animals. Our results suggest that the lethal dose of benzocaine in gel used inside the mouth of frogs may have no influence on potential results regarding the chemical composition or even bioassays using extracts made from the skin of these animals killed under this protocol since there was no detection of this substance for the analyzed samples.


Assuntos
Anestésicos/análise , Anuros , Benzocaína/análise , Pele/química , Extratos de Tecidos/análise , Anestésicos/administração & dosagem , Animais , Benzocaína/administração & dosagem , Colágeno , Espectroscopia de Prótons por Ressonância Magnética , Manejo de Espécimes/métodos , Extratos de Tecidos/química
10.
Toxicon ; 186: 126-140, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32805296

RESUMO

Freshwater stingrays are cartilaginous fish with stingers at the base of their tail. The stinger is covered with an epithelium containing mucous and venom glands. Human envenomation usually occurs when a person steps on a stingray hiding in the sand and the fish sinks its stinger into the victim, causing an extremely painful wound which generally leads to tissue necrosis. Medical treatment is based on the use of painkillers, anti-inflammatory drugs and antibiotics, as there is to date no specific antidote for envenomation by freshwater stingrays. The aim of this study was therefore to investigate whether sera containing anti-P. motoro antibodies can neutralize the edema-forming and myotoxic activities of Potamotrygon motoro venom. To this end, two protocols were used: seroneutralization and vaccination of mice. The seroneutralization protocol involved intramuscular injection of the P. motoro venom in the mice gastrocnemius followed by administration of hyperimmune mouse serum anti P. motoro dorsal extract and stinger extract via the ophthalmic venous plexus. The vaccination protocol involved immunizing the mice with dorsal or stinger extract adsorbed to aluminum hydroxide followed by intramuscular challenge with the P. motoro venom. The gastrocnemii of all the animals were removed for histopathological and stereological analyses, and blood was collected via the ophthalmic venous plexus to measure IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-γ, TNF, C-reactive protein and total creatine kinase. Protocols did not neutralize the edema-forming or local myotoxic induced by P. motoro venom under the experimental conditions tested. But systemic rhabdomyolysis was only completely neutralized in animals vaccinated with the stinger extract. Cytokine analysis revealed that under the experimental conditions used here, seroneutralization induced release of Th1, Th2, Th17 and Treg cytokines whereas vaccination induced a Th1 response.


Assuntos
Elasmobrânquios , Venenos de Peixe/toxicidade , Miotoxicidade , Animais , Antivenenos , Edema/induzido quimicamente , Imunoglobulinas
11.
Toxicon ; 184: 99-108, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32522619

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: In the region of Western Pará, Amazonia, Brazil, Philodendron megalophyllum is widely used for the treatment of envenomations caused by bites from venomous snakes. The traditional use of plants is usually done through oral administration of an infusion (decoction) soon after the bite occurs. The efficiency of aqueous extracts of P. megalophyllum was demonstrated for blocking the activity of the venom of Bothrops sp., but only for a pre-incubation protocol (venom:extract), which fails to simulate the real form of use of this species. In this context, the objective of this research was to evaluate the anti-snakebite potential of the aqueous extract of P. megalophyllum to inhibit for the biological activity induced by Bothrops atrox venom (BaV) using traditional treatment methods. MATERIAL AND METHODS: Initially, an aqueous extract using the stem of P. megalophyllum (AEPm) was prepared following the standard procedure used by the residents of the rural area along the Tapajós River (Eixo Forte region) in Santarém, PA, Brazil. The phytochemical profile of AEPm was conducted using thin layer chromatography (TLC) and phenolic compounds were quantified through colorimetric trials. The cytotoxicity of AEPm was evaluated using the MRC-5 human fibroblast line, and the antioxidant potential was measured using DPPH methods and cell culture. AEPm antimicrobial action was evaluated by the 96-well plate microdilution and the minimum inhibitory concentration (MIC) methods using 18 types of microorganisms including bacteria that are present in the oral cavity of snakes. AEPm blocking potential was tested against BaV activity in vitro (fibrinolytic) and in vivo (defibrinating and hemorrhagic). In order to test for an interaction between BaV and AEPm SDS-PAGE electrophoresis was conducted. RESULTS: The presence of coumarins, fatty acids, and hydrolysable tannins were detected in the AEPm. The colorimetric trials showed that AEPm had a high concentration of condensed tannins (20.1 ± 1.2%). The potential of AEPm for blocking of hemorrhagic and fibrinolytic activity of BaV showed a maximum reduction of 86.1% and 96.5%, respectively, for the pre-incubation protocol (1:10, venom:extract). However, when the extract was administered orally there was no significant blocking of these activities. The interaction of BaV and AEPm showed a modification of the profile of proteic bands when compared to the pattern of bands obtained from the BaV alone. The AEPm was not considered toxic, demonstrated antioxidant activity, and was capable of reducing the growth of 10 of the 18 studied microorganisms. CONCLUSION: Although the stem of P. megalophyllum is indicated by traditional medicine techniques as effective against snakebites, the extract, when tested orally was not able to significantly inhibit (p ˃ 0.05) hemorrhage and defibrinating activity induced by the B. atrox venom. On the other hand, the extract yielded a promising result with respect to antioxidant and antimicrobial potential, and after further studies it could be used as a complementary treatment for localized action and secondary infections that frequently occur with snakebites from the genus of Bothrops sp.


Assuntos
Antibacterianos/uso terapêutico , Extratos Vegetais/uso terapêutico , Mordeduras de Serpentes/tratamento farmacológico , Animais , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Antivenenos/uso terapêutico , Venenos de Crotalídeos , Hemorragia/tratamento farmacológico , Humanos , Medicina Tradicional , Philodendron , Extratos Vegetais/farmacologia
12.
Toxicon ; 184: 99-108, 2020.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib17720

RESUMO

Ethnopharmacological relevance In the region of Western Pará, Amazonia, Brazil, Philodendron megalophyllum is widely used for the treatment of envenomations caused by bites from venomous snakes. The traditional use of plants is usually done through oral administration of an infusion (decoction) soon after the bite occurs. The efficiency of aqueous extracts of P. megalophyllum was demonstrated for blocking the activity of the venom of Bothrops sp., but only for a pre-incubation protocol (venom:extract), which fails to simulate the real form of use of this species. In this context, the objective of this research was to evaluate the anti-snakebite potential of the aqueous extract of P. megalophyllum to inhibit for the biological activity induced by Bothrops atrox venom (BaV) using traditional treatment methods. Material and methods Initially, an aqueous extract using the stem of P. megalophyllum (AEPm) was prepared following the standard procedure used by the residents of the rural area along the Tapajós River (Eixo Forte region) in Santarém, PA, Brazil. The phytochemical profile of AEPm was conducted using thin layer chromatography (TLC) and phenolic compounds were quantified through colorimetric trials. The cytotoxicity of AEPm was evaluated using the MRC-5 human fibroblast line, and the antioxidant potential was measured using DPPH methods and cell culture. AEPm antimicrobial action was evaluated by the 96-well plate microdilution and the minimum inhibitory concentration (MIC) methods using 18 types of microorganisms including bacteria that are present in the oral cavity of snakes. AEPm blocking potential was tested against BaV activity in vitro (fibrinolytic) and in vivo (defibrinating and hemorrhagic). In order to test for an interaction between BaV and AEPm SDS-PAGE electrophoresis was conducted. Results The presence of coumarins, fatty acids, and hydrolysable tannins were detected in the AEPm. The colorimetric trials showed that AEPm had a high concentration of condensed tannins (20.1 ± 1.2%). The potential of AEPm for blocking of hemorrhagic and fibrinolytic activity of BaV showed a maximum reduction of 86.1% and 96.5%, respectively, for the pre-incubation protocol (1:10, venom:extract). However, when the extract was administered orally there was no significant blocking of these activities. The interaction of BaV and AEPm showed a modification of the profile of proteic bands when compared to the pattern of bands obtained from the BaV alone. The AEPm was not considered toxic, demonstrated antioxidant activity, and was capable of reducing the growth of 10 of the 18 studied microorganisms. Conclusion Although the stem of P. megalophyllum is indicated by traditional medicine techniques as effective against snakebites, the extract, when tested orally was not able to significantly inhibit (p > 0.05) hemorrhage and defibrinating activity induced by the B. atrox venom. On the other hand, the extract yielded a promising result with respect to antioxidant and antimicrobial potential, and after further studies it could be used as a complementary treatment for localized action and secondary infections that frequently occur with snakebites from the genus of Bothrops sp

13.
Toxicon, v. 184, p. 99-108, set. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3062

RESUMO

Ethnopharmacological relevance In the region of Western Pará, Amazonia, Brazil, Philodendron megalophyllum is widely used for the treatment of envenomations caused by bites from venomous snakes. The traditional use of plants is usually done through oral administration of an infusion (decoction) soon after the bite occurs. The efficiency of aqueous extracts of P. megalophyllum was demonstrated for blocking the activity of the venom of Bothrops sp., but only for a pre-incubation protocol (venom:extract), which fails to simulate the real form of use of this species. In this context, the objective of this research was to evaluate the anti-snakebite potential of the aqueous extract of P. megalophyllum to inhibit for the biological activity induced by Bothrops atrox venom (BaV) using traditional treatment methods. Material and methods Initially, an aqueous extract using the stem of P. megalophyllum (AEPm) was prepared following the standard procedure used by the residents of the rural area along the Tapajós River (Eixo Forte region) in Santarém, PA, Brazil. The phytochemical profile of AEPm was conducted using thin layer chromatography (TLC) and phenolic compounds were quantified through colorimetric trials. The cytotoxicity of AEPm was evaluated using the MRC-5 human fibroblast line, and the antioxidant potential was measured using DPPH methods and cell culture. AEPm antimicrobial action was evaluated by the 96-well plate microdilution and the minimum inhibitory concentration (MIC) methods using 18 types of microorganisms including bacteria that are present in the oral cavity of snakes. AEPm blocking potential was tested against BaV activity in vitro (fibrinolytic) and in vivo (defibrinating and hemorrhagic). In order to test for an interaction between BaV and AEPm SDS-PAGE electrophoresis was conducted. Results The presence of coumarins, fatty acids, and hydrolysable tannins were detected in the AEPm. The colorimetric trials showed that AEPm had a high concentration of condensed tannins (20.1 ± 1.2%). The potential of AEPm for blocking of hemorrhagic and fibrinolytic activity of BaV showed a maximum reduction of 86.1% and 96.5%, respectively, for the pre-incubation protocol (1:10, venom:extract). However, when the extract was administered orally there was no significant blocking of these activities. The interaction of BaV and AEPm showed a modification of the profile of proteic bands when compared to the pattern of bands obtained from the BaV alone. The AEPm was not considered toxic, demonstrated antioxidant activity, and was capable of reducing the growth of 10 of the 18 studied microorganisms. Conclusion Although the stem of P. megalophyllum is indicated by traditional medicine techniques as effective against snakebites, the extract, when tested orally was not able to significantly inhibit (p > 0.05) hemorrhage and defibrinating activity induced by the B. atrox venom. On the other hand, the extract yielded a promising result with respect to antioxidant and antimicrobial potential, and after further studies it could be used as a complementary treatment for localized action and secondary infections that frequently occur with snakebites from the genus of Bothrops sp

14.
Rev. bras. farmacogn ; 28(6): 697-702, Nov.-Dec. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-977742

RESUMO

ABSTRACT Candida spp. is associated with almost 80% of all nosocomial fungal infections and is considered a major cause of blood stream infections. In humans, Cryptococcosis is a disease of the lungs caused by the fungi Cryptococcus gattii and Cryptococcus neoformans. It can be potentially fatal, especially in immune-compromised patients. In a search for antifungal drugs, Deguelia duckeana extracts were assayed against these two fungi and also against Candida albicans, which causes candidiasis. Hexane branches and CH2Cl2 root extracts as well as the substances 4-hydroxylonchocarpine, 3,5,4′-trimethoxy-4-prenylstilbene and 3′,4′-methylenedioxy-7-methoxyflavone were assayed to determine the minimal inhibitory concentration. Phytochemical study of CH2Cl2 root and hexane branch extracts from D. duckeana A.M.G. Azevedo, Fabaceae, resulted in the isolation and characterization of nine phenolic compounds: 4-hydroxyderricine, 4-hydroxylonchocarpine, 3′,4′,7-trimethoxy-flavonol, 5,4′-dihydroxy-isolonchocarpine, 4-hydroxyderricidine, derricidine, 3,5,4′-trimethoxy-stilbene, 3′,4′,7-trimethoxyflavone and yangambin. The only active extract was a CH2Cl2 root showing minimal inhibitory concentration 800 µg/ml against C. gattii, and the investigation of compounds obtained from this extract showed that 4-hydroxylonchocarpine was active against all three fungi (C. neoformans, C. gattii and C. albicans). These results suggest that D. duckeana extracts have potential therapeutic value for the treatment of pathogenic fungi.

15.
Oxid Med Cell Longev ; 2018: 9241308, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30116496

RESUMO

Guarana (Paullinia cupana) is largely consumed in Brazil in high energy drinks and dietary supplements because of its stimulant activity on the central nervous system. Although previous studies have indicated that guarana has some protective effects in Parkinson's (PD), Alzheimer's (AD), and Huntington's (HD) disease models, the underlying mechanisms are unknown. Here, we investigated the protective effects of guarana hydroalcoholic extract (GHE) in Caenorhabditis elegans models of HD and AD. GHE reduced polyglutamine (polyQ) protein aggregation in the muscle and also reduced polyQ-mediated neuronal death in ASH sensory neurons and delayed ß-amyloid-induced paralysis in a caffeine-independent manner. Moreover, GHE's protective effects were not mediated by caloric restriction, antimicrobial effects, or development and reproduction impairment. Inactivation of the transcription factors SKN-1 and DAF-16 by RNAi partially blocked the protective effects of GHE treatment in the AD model. We show that the protective effect of GHE is associated with antioxidant activity and modulation of proteostasis, since it increased the lifespan and proteasome activity, reduced intracellular ROS and the accumulation of autophagosomes, and increased the expression of SOD-3 and HSP-16.2. Our findings suggest that GHE has therapeutic potential in combating age-related diseases associated with protein misfolding and accumulation.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Antioxidantes/metabolismo , Doença de Huntington/tratamento farmacológico , Paullinia/metabolismo , Extratos Vegetais/uso terapêutico , Animais , Caenorhabditis elegans/efeitos dos fármacos , Extratos Vegetais/farmacologia
16.
Acta amaz ; 46(2): 189-194, abr.-jun. 2016. ilus, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1455295

RESUMO

The Amazon forest is rich in plant species diversity, among them,Piranhea trifoliata stands out, which is popularly known as piranheira, because their fruits are eaten by fish. Their barks are used as bath composition on uterus inflammation and as tea in malaria treatment. This study aimed to fractionate the dichloromethane and dichloromethane phase from methanolic extract of leaves of Piranhea trifoliata. The leaves were dried, grounded and extracted with dichloromethane, methanol and water. The methanol extract was partitioned with dichloromethane and ethyl acetate. The chromatographic fractionation yielded six pentacyclic triterpenoids: friedelan-3-one, 28-hydroxy-friedelan-3-one, 30-hydroxy-friedelan-3-one, lupeol, alfa- and beta-amyrin mixture, besides the mixture of the steroids: beta-sitosterol and stigmasterol. The substances structures were identified by 1H- and13C-Nuclear Magnetic Resonance (NMR) analysis and literature data comparison. This is the first report describing the chemical study of P. trifoliata leaves.


A floresta Amazônica é rica em diversas espécies vegetais, dentre elas, destaca-se Piranhea trifoliata, a qual é conhecida popularmente como piranheira, por seus frutos servirem de alimentos para peixes. Suas cascas são utilizadas como curativo para inflamação no útero em banhos de assento e para chás no tratamento de malária. O objetivo deste trabalho foi o fracionamento cromatográfico do extrato diclorometânico e da fase diclorometânica do extrato metanólico das folhas de Piranhea trifoliata. As folhas foram secas, moídas e extraídas com diclorometano, metanol e água. O extrato metanólico foi submetido à partição com diclorometano e acetato de etila. O fracionamento cromatográfico conduziu ao isolamento de seis triterpenoides pentacíclicos: friedelan-3-ona, 28-hidroxi-friedelan-3-ona, 30-hidroxi-friedelan-3-ona, lupeol, mistura de alfa- e beta-amirina, além da mistura dos esteroides beta-sitosterol e estigmasterol. As estruturas das substâncias foram identificadas pela análise dos espectros de Ressonância Magnética Nuclear (RMN) de 1H e de 13C e comparações com dados da literatura. Este é o primeiro relato descrevendo o estudo químico das folhas de P. trifoliata.


Assuntos
Extratos Vegetais/análise , Folhas de Planta/química , Árvores/química , Cromatografia , Esteroides
18.
J Ethnopharmacol ; 183: 166-175, 2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-26940897

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The plant species Connarus favosus is used in folk medicine in the west of Pará state, Brazil, to treat snakebites. AIM OF THE STUDY: To investigate the potential of the aqueous extract of Connarus favosus (AECf) to inhibit hemorrhagic and phospholipase A2 activities induced by Bothrops atrox venom (BaV) and to determine the antioxidant and antimicrobial potentials of the extract. MATERIALS AND METHODS: AECf was analyzed phytochemically for phenolics (condensed tannins and hydrolyzable tannins) by colorimetry. Antioxidant activity was evaluated by quantitative assays using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Fe(3+)/phenanthroline. Antimicrobial activity was evaluated by the minimal inhibitory concentration test, and cytotoxicity was evaluated using human fibroblast cells (MRC-5). Inhibition of BaV-induced hemorrhagic activity was assessed after oral administration of the extract using pre-treatment, post-treatment and combined (BA plus AECf) treatment protocols. Inhibition of indirect hemolysis caused by phospholipase A2 (PLA2) was investigated in vitro. Interaction between AECf and BaV was investigated by SDS-PAGE electrophoresis, Western blot (Wb) and zymography. RESULTS: The phytochemical profile of AECf revealed ten secondary metabolite classes, and colorimetry showed high total phenolic and total (condensed and hydrolyzable) tannin content. AECf exhibited high antioxidant and antimicrobial potentials. The IC50 for the cytotoxic effect was 51.91 (46.86-57.50)µg/mL. Inhibition of BaV-induced hemorrhagic activity was significant in all the protocols, and inhibition of PLA2 activity was significant with the two highest concentrations. The BaV/AECf mixture produced the same bands as BaV by itself in SDS-PAGE and Wb although the bands were much fainter. Zymography confirmed the proteolytic activity of BaV, but when the venom was pre-incubated with AECf this activity was blocked. CONCLUSION: AECf was effective in reducing BaV-induced hemorrhagic activity when administered by the same route as that used in folk medicine and exhibited antioxidant and antimicrobial potentials.


Assuntos
Antibacterianos/farmacologia , Antivenenos/farmacologia , Connaraceae/química , Venenos de Crotalídeos/administração & dosagem , Hemorragia/tratamento farmacológico , Extratos Vegetais/farmacologia , Animais , Antibacterianos/química , Antioxidantes/farmacologia , Antivenenos/química , Bothrops , Brasil , Feminino , Hemorragia/metabolismo , Masculino , Medicina Tradicional/métodos , Camundongos , Fosfolipases A2/metabolismo , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Mordeduras de Serpentes/tratamento farmacológico , Taninos/metabolismo
19.
BMC Complement Altern Med ; 16: 83, 2016 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-26921197

RESUMO

BACKGROUND: The Amazon is the largest rainforest in the world and is home to a rich biodiversity of medicinal plants. Several of these plants are used by the local population for the treatment of diseases, many of those with probable anti-inflammatory effect. The aim of the present investigation was to evaluate the in vitro antioxidant and anti-peroxidases potential of the ethanol extracts of five plants from the Brazilian Amazon (Byrsonima japurensis, Calycophyllum spruceanum, Maytenus guyanensis, Passiflora nitida and Ptychopetalum olacoides). METHODS: DPPH, ABTS, superoxide anion radical, singlet oxygen and the ß-carotene bleaching methods were employed for characterization of free radical scavenging activity. Also, total polyphenols were determined. Antioxidant activities were evaluated using murine fibroblast NIH3T3 cell. Inhibition of HRP and MPO were evaluated using amplex red® as susbtract. RESULTS: The stem bark extracts of C. spruceanum and M. guyanensis provided the highest free radical scavenging activities. C. spruceanum exhibited IC50 = 7.5 ± 0.9, 5.0 ± 0.1, 18.2 ± 3.0 and 92.4 ± 24.8 µg/mL for DPPH(•), ABTS(+•), O2 (-•) and (1)O2 assays, respectively. P. olacoides and C. spruceanum extracts also inhibited free radicals formation in the cell-based assay. At a concentration of 100 µg/mL, the extracts of C. spruceanum, B. japurensis inhibited horseradish peroxidase by 62 and 50 %, respectively. C. spruceanum, M. guyanensis, B. japurensis also inhibited myeloperoxidase in 72, 67 and 56 %, respectively. CONCLUSIONS: This work supports the folk use these species that inhibited peroxidases and exhibited significant free radical scavenging and antioxidant activities what can be related to treatment of inflammation.


Assuntos
Antioxidantes/farmacologia , Malpighiaceae/química , Maytenus/química , Olacaceae/química , Passiflora/química , Peroxidases/antagonistas & inibidores , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Brasil , Humanos , Medicina Tradicional , Camundongos , Células NIH 3T3 , Peroxidase , Fitoterapia , Plantas Medicinais/química , Polifenóis/análise , Polifenóis/farmacologia
20.
Molecules ; 21(2)2016 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-26861281

RESUMO

Preparations of Deguelia duckeana, known in Brazil as timbó, are used by indigenous people to kill fish. Reinvestigation of its extracts resulted in the isolation and identification of 11 known flavonoids identified as 3,5,4'-trimethoxy-4-prenylstilbene (1), 4-methoxyderricidine (2), lonchocarpine (3), 4-hydroxylonchocarpine (4), 4-methoxylonchocarpine (5), 5-hydroxy-4',7-dimethoxy-6-prenylflavanone (6), 4'-hydroxyisolonchocarpine (7), 4'-methoxyisolonchocarpine (8), 3',4',7-trimethoxyflavone (9), 3',4'-methylenedioxy-7-methoxyflavone (10), and 2,2-dimethyl-chromone-5,4'-hydroxy-5'-methoxyflavone (11). Except for 1, 3, and 4 all of these flavonoids have been described for the first time in D. duckeana and the flavanone 6 for the first time in nature. Compounds 2, 3, 4, 7, 9, and 10 were studied for their potential to induce cell death in neuronal SK-N-SH cells. Only the chalcone 4 and the flavanone 7 significantly induced lactate dehydrogenase (LDH) release, which was accompanied by activation of caspase-3 and impairment of energy homeostasis in the MTT assay and may explain the killing effect on fish. Interestingly, the flavone 10 reduced cell metabolism in the MTT assay without inducing cytotoxicity in the LDH assay. Furthermore, the flavonoids 2, 3, 4, 7, and 10 induced phosphorylation of the AMP-activated protein kinase (AMPK) and the eukaryotic elongation factor 2 (eEF2). The initiation factor eIF4E was dephosphorylated in the presence of these compounds. The initiation factor eIF2alpha was not affected. Further studies are needed to elucidate the importance of the observed effects on protein synthesis and potential therapeutic perspectives.


Assuntos
Fabaceae/química , Flavonoides/toxicidade , Extratos Vegetais/toxicidade , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Adenilato Quinase/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fator de Iniciação 2 em Eucariotos/metabolismo , Fator de Iniciação 4E em Eucariotos/metabolismo , Flavonoides/isolamento & purificação , Humanos , Fator 2 de Elongação de Peptídeos/metabolismo , Fosforilação , Extratos Vegetais/isolamento & purificação
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