Antinociceptive effect of Nephelium lappaceum L. fruit peel and the participation of nitric oxide, opioid receptors, and ATP-sensitive potassium channels

Introduction:Nephelium lappaceum L. (Sapindaceae) is a plant known as rambutan. It is used for various purposes in traditional medicine.Objective: We aimed to evaluate the antinociceptive effects of the ethanol extract of the fruit peel of N. lappaceum (EENL), the mechanisms involved in these effects, and the acute toxicity in zebrafish.Methods: We performed chromatography coupled to mass spectrometry, acute toxicity assay in zebrafish, and evaluation in mice submitted to models of nociception and locomotor activity.Results: We identified (epi)-catechin, procyanidin B, and ellagic acid and its derivatives in EENL. We did not find any toxicity in zebrafish embryos incubated with EENL. The locomotor activity of mice submitted to oral pretreatment with EENL was not changed, but it reduced the abdominal constrictions induced by acetic acid, the licking/biting time in both the first and second phase of formalin testing and capsaicin testing, and carrageenan-induced paw mechanical allodynia. Oral pretreatment with EENL increased latency time in the hot plate test. This antinociceptive effect was significantly reversed by naloxone, L-arginine, and glibenclamide respectively showing the participation of opioid receptors, nitric oxide, and KATP channels as mediators of EENL-induced antinociception.Conclusion: EENL causes antinociception with the participation of opioid receptors, nitric oxide, and KATP channels, and is not toxic to zebrafish

Die Chitosan-induzierte Abwehrreaktion des Weizens

Eine Inokulation anfälliger Weizensorten mit dem phytopathogenen Rostpilz Puccinia graminis f.sp. tritici (Pgt) führt zur Erkrankung der Pflanze an Schwarzrost. In hochresistenten Weizensorten kann die Pflanze eine Infektion durch den obligat biotrophen Pilz abwehren, indem infizierte Zellen lignifizieren und absterben. Substanzen, die bei Applikation ähnliche Abwehrreaktionen induzieren können, werden Elicitoren genannt. In Blätter infiltriertes polymeres Chitosan wirkt in Weizen als Elicitor einer heterogenen Reaktion, welche mit einer gradiellen Verteilung des Elicitors im Gewebe und einer zeitlich differenziellen Induktion zweier Gene der Ligninbiosynthese korrelliert, der Zimtsäure-4-hydroxylase (C4H) bzw. Zimtalkohol-dehydrogenase (CAD). Die Induktion der C4H wird von einer Nekrotisierung des Gewebes begleitet. Eine Lignifizierung, korrellierend mit einer CAD-Induktion, findet jedoch nur an der Grenze der Nekrose zum intakten Gewebe statt. Die kinetischen Untersuchungen wurden auch auf einen aus Keimschläuchen des Pilzes isolierbaren Elicitor bzw. das natürliche Interaktionssystem erweitert

Synthesis and Antiplasmodial Activity of 2-Methyl-3- Carboxyl-Naphtho [2, 3-B] Furan Quinone Derivatives

Submitted by Nuzia Santos ([email protected]) on 2018-08-24T13:06:50Z No. of bitstreams: 1 Synthesis and Antiplasmodial Activity of 2-Methyl-3-Carboxyl-Naphtho.pdf: 663651 bytes, checksum: ddbc1dc5fc22a7c49a78c618805d8e6f (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2018-08-24T13:11:10Z (GMT) No. of bitstreams: 1 Synthesis and Antiplasmodial Activity of 2-Methyl-3-Carboxyl-Naphtho.pdf: 663651 bytes, checksum: ddbc1dc5fc22a7c49a78c618805d8e6f (MD5)Made available in DSpace on 2018-08-24T13:11:10Z (GMT). No. of bitstreams: 1 Synthesis and Antiplasmodial Activity of 2-Methyl-3-Carboxyl-Naphtho.pdf: 663651 bytes, checksum: ddbc1dc5fc22a7c49a78c618805d8e6f (MD5) Previous issue date: 2018Fundação Oswaldo Cruz. Instituto René Rachou. Laboratório de Química de Produtos Naturais Bioativos. Belo Horizonte MG, Brasil.Fundação Oswaldo Cruz. Instituto René Rachou. Laboratório de Malária Experimental e Humana. Belo Horizonte MG, Brasil.Fundação Oswaldo Cruz. Instituto René Rachou. Laboratório de Química de Produtos Naturais Bioativos. Belo Horizonte MG, Brasil.Fundação Oswaldo Cruz. Instituto René Rachou. Laboratório de Malária Experimental e Humana. Belo Horizonte MG, Brasil.Fundação Oswaldo Cruz. Instituto René Rachou. Laboratório de Química de Produtos Naturais Bioativos. Belo Horizonte MG, Brasil.Malaria, a disease caused by the Plasmodium parasite, has spread globally, mainly in the African subcontinent. Species of parasites resistant to usual drugs like chloroquine, used to treat malaria, have led research groups to search for new drugs to expand the current therapeutic arsenal. Fourteen 2-methyl-3-carboxylnaphtho[2,3-b]furan quinone derivatives (FNQ) were synthesized and evaluated using cultures of Plasmodium falciparum in vitro. From all FNQ derivatives tested, six of them (4,7-10,14) showed IC50 values ranging from 0.05 μM to 11.3 μM. The glutamine-FNQ (9) and spermidine-FNQ derivatives (14) were the best antiplasmodial molecules tested, with selectivity indexes of 56 and 75, respectively. Our data suggests these two compounds are appropriate candidates for investigation as potential antimalarial drugs against drug-resistant Plasmodium species

Aspidosperma pyrifolium, a medicinal plant from the Brazilian caatinga, displays a high antiplasmodial activity and low cytotoxicity

Abstract Background Several species of Aspidosperma plants are referred to as remedies for the treatment of malaria, especially Aspidosperma nitidum. Aspidosperma pyrifolium, also a medicinal plant, is used as a natural anti-inflammatory. Its fractionated extracts were assayed in vitro for activity against malaria parasites and for cytotoxicity. Methods Aspidosperma pyrifolium activity was evaluated against Plasmodium falciparum using extracts in vitro. Toxicity towards human hepatoma cells, monkey kidney cells or human monocytes freshly isolated from peripheral blood was also assessed. Anti-malarial activity of selected extracts and fractions that presented in vitro activity were tested in mice with a Plasmodium berghei blood-induced infection. Results The crude stem bark extract and the alkaloid-rich and ethyl acetate fractions from stem extract showed in vitro activity. None of the crude extracts or fractions was cytotoxic to normal monkey kidney and to a human hepatoma cell lines, or human peripheral blood mononuclear cells; the MDL50 values of all the crude bark extracts and fractions were similar or better when tested on normal cells, with the exception of organic and alkaloidic-rich fractions from stem extract. Two extracts and two fractions tested in vivo caused a significant reduction of P. berghei parasitaemia in experimentally infected mice. Conclusion Considering the high therapeutic index of the alkaloidic-rich fraction from stem extract of A. pyrifolium, it makes the species a candidate for further investigation aiming to produce a new anti-malarial, especially considering that the active extract has no toxicity, i.e., no mutagenic effects in the genototoxicity assays, and that it has an in vivo anti-malarial effect. In its UPLC-HRMS analysis this fraction was shown to have two major components compatible with the bisindole alkaloid Leucoridine B, and a novel compound, which is likely to be responsible for the activity against malaria parasites demonstrated in in vitro tests

Unprecedented one-pot sequence for the synthesis of tetrahydroquinoline alkaloids and preliminary evaluation of their antibacterial activity

O link não abre! Favor corrigir.A novel one-pot sequence (in 2 or 3 steps) was developed for the synthesis of the tetrahydroquinoline alkaloids (±)-galipinine, (±)-cuspareine, (±)-galipeine and (±)-angustureine, and the derivative (±)-11-methoxy-5,6,6a,7,8,13-hexahydro-13a-aza-benzo[5,6]cyclohepta [1,2-a]naphthalene-12-ol from their respective Wittig adducts in moderate and high yields. The solvolytic N-methylation reaction was shown to be catalyzed by Pt0, generated in situ by reduction of PtO2. The evaluation of biofilm inhibition and antibacterial activity of the compounds against Staphylococcus aureus strains isolated from cows with mastitis revealed that the alkaloid derivative is a promising candidate for an antibiotic drug

Antifungal activity of extracts from Atacama Desert fungi against Paracoccidioides brasiliensis and identification of Aspergillus felis as a promising source of natural bioactive compounds

Submitted by Nuzia Santos ([email protected]) on 2016-08-22T13:59:12Z No. of bitstreams: 1 ve_Mendes_Graziele_ Antifungal_CPqRR_2016.pdf: 614207 bytes, checksum: 63480c12960be7ef23f94df4e4a6d7da (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2016-08-22T14:05:49Z (GMT) No. of bitstreams: 1 ve_Mendes_Graziele_ Antifungal_CPqRR_2016.pdf: 614207 bytes, checksum: 63480c12960be7ef23f94df4e4a6d7da (MD5)Made available in DSpace on 2016-08-22T14:05:49Z (GMT). No. of bitstreams: 1 ve_Mendes_Graziele_ Antifungal_CPqRR_2016.pdf: 614207 bytes, checksum: 63480c12960be7ef23f94df4e4a6d7da (MD5) Previous issue date: 2016Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Belo Horizonte, MG, Brasil/Fundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Laboratório de Química de Produtos Naturais. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Departamento de Fisiologia e Biofísica. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Laboratório de Química de Produtos Naturais. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Laboratório de Química de Produtos Naturais. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Laboratório de Química de Produtos Naturais. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Belo Horizonte, MG, BrasilFungi of the genus Paracoccidioides are responsible for paracoccidioidomycosis. The occurrence of drug toxicity and relapse in this disease justify the development of new antifungal agents. Compounds extracted from fungal extract have showing antifungal activity. Extracts of 78 fungi isolated from rocks of the Atacama Desert were tested in a microdilution assay against Paracoccidioides brasiliensis Pb18. Approximately 18% (5) of the extracts showed minimum inhibitory concentration (MIC) values≤ 125.0 µg/mL. Among these, extract from the fungus UFMGCB 8030 demonstrated the best results, with an MIC of 15.6 µg/mL. This isolate was identified as Aspergillus felis (by macro and micromorphologies, and internal transcribed spacer, β-tubulin, and ribosomal polymerase II gene analyses) and was grown in five different culture media and extracted with various solvents to optimise its antifungal activity. Potato dextrose agar culture and dichloromethane extraction resulted in an MIC of 1.9 µg/mL against P. brasiliensis and did not show cytotoxicity at the concentrations tested in normal mammalian cell (Vero). This extract was subjected to bioassay-guided fractionation using analytical C18RP-high-performance liquid chromatography (HPLC) and an antifungal assay using P. brasiliensis. Analysis of the active fractions by HPLC-high resolution mass spectrometry allowed us to identify the antifungal agents present in the A. felis extracts cytochalasins. These results reveal the potential of A. felis as a producer of bioactive compounds with antifungal activity

Identification, characterization and quantification of xanthones from Fridericia formosa leaves extract with antiviral activity

Abstract Fridericia formosa (Bureau) L.G. Lohmann (Bignonaceae) is a neotropical liana species found in the Cerrado biome in Brazil. It has been of great interest to the scientific community due to its potential as a source of new antivirals, including xanthones derived from mangiferin. In this context, the present study aimed to characterize and quantify the xanthones present in the ethanol extract of this species using high performance liquid chromatography. Additionally, the antiviral activity against Chikungunya, Zika, and Mayaro viruses was evaluated. The chromatographic analyses partially identified twenty-six xanthones, among which only fourteen had already been described in the literature. The xanthones mangiferin, 2′-O-trans-caffeoylmangiferin, and 2′-O-trans-coumaroylmangiferin, are present in higher quantities in the extract, at concentrations of 9.65%, 10.68%, and 3.41% w/w, respectively. In antiviral assays, the extract inhibited the multiplication cycle only for the Mayaro virus with a CE50 of 36.1 μg/mL. Among the isolated xanthones, 2′-O-trans-coumaroylmangiferin and 2′-O-trans-cinnamoylmangiferin inhibited the viral cytopathic effect with CE50 values of 180.6 and 149.4 μg/mL, respectively. Therefore, the extract from F. formosa leaves, which has a high content of xanthones, has antiviral potential and can be a source of new mangiferin derivatives