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1.
Philos Trans A Math Phys Eng Sci ; 382(2273): 20230199, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38736332

RESUMO

The DESTINY+(Demonstration and Experiment of Space Technology for INterplanetary voYage with Phaethon fLyby and dUst Science) Dust Analyser (DDA) is a state-of-the-art dust telescope for the in situ analysis of cosmic dust particles. As the primary scientific payload of the DESTINY+ mission, it serves the purpose of characterizing the dust environment within the Earth-Moon system, investigating interplanetary and interstellar dust populations at 1 AU from the Sun and studying the dust cloud enveloping the asteroid (3200) Phaethon. DDA features a two-axis pointing platform for increasing the accessible fraction of the sky. The instrument combines a trajectory sensor with an impact ionization time-of-flight mass spectrometer, enabling the correlation of dynamical, physical and compositional properties for individual dust grains. For each dust measurement, a set of nine signals provides the surface charge, particle size, velocity vector, as well as the atomic, molecular and isotopic composition of the dust grain. With its capabilities, DDA is a key asset in advancing our understanding of the cosmic dust populations present along the orbit of DESTINY+. In addition to providing the scientific context, we are presenting an overview of the instrument's design and functionality, showing first laboratory measurements and giving insights into the observation planning. This article is part of a theme issue 'Dust in the Solar System and beyond'.

2.
IBRO Rep ; 9: 164-182, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32803016

RESUMO

Vanadium, a transition series metal released during some industrial activities, induces oxidative stress and lipid peroxidation. Ameliorative effect of a pure compound from the methanolic extract of Moringa oleifera leaves, code-named MIMO2, in 14-day old mice administered with vanadium (as sodium metavanadate 3 mg/kg) for 2 weeks was assessed. Results from body weight monitoring, muscular strength, and open field showed slight reduction in body weight and locomotion deficit in vanadium-exposed mice, ameliorated with MIMO2 co-administration. Degeneration of the Purkinje cell layer and neuronal death in the hippocampal CA1 region were observed in vanadium-exposed mice and both appeared significantly reduced with MIMO2 co-administration. Demyelination involving the midline of the corpus callosum, somatosensory and retrosplenial cortices was also reduced with MIMO2. Microglia activation and astrogliosis observed through immunohistochemistry were also alleviated. Immunohistochemistry for myelin, axons and oligodendrocyte lineage cells were also carried out and showed that in vanadium-treated mice brains, oligodendrocyte progenitor cells increased NG2 immunolabelling with hypertrophy and bushy, ramified appearance of their processes. MIMO2 displayed ameliorative and antioxidative effects in vanadium-induced neurotoxicity in experimental murine species. This is likely the first time MIMO2 is being used in vivo in an animal model.

3.
Planta Med ; 86(8): 565-570, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32325509

RESUMO

Bacopa monnieri is an Ayurvedic plant with rising interest in the pharmacological effects of its extract and constituents, including flavonoids, saponins, and triterpenes such as cucurbitacins, betulinic acid, and bacosine. The latter two compounds are isomeric 3-hydroxy lupenoic acids, which vary only in the arrangement of the carboxylic acid group and the methyl group at C-27 and C-28 and the orientation of the hydroxy group at C-3. In this study, we have reinvestigated the contents of betulinic acid and bacosine, respectively, in extracts from various commercially available B. monnieri powders and food supplements. To our surprise, HPLC-ion trap time-of-flight analyses identified only betulinic acid, but not bacosine, in all extracts under study, which was verified by GC-MS, HPLC-ELSD, 1D NMR (1H,13C), and 2D NMR (1H,1H COSY, 1H,13C HMBC, 1H,13C HSQC, 1H,1H NOESY) experiments. Moreover, it turned out that commercially available reference samples of bacosine were structurally identical with betulinic acid.


Assuntos
Bacopa , Saponinas , Triterpenos , Cromatografia Líquida de Alta Pressão , Extratos Vegetais
4.
Drug Chem Toxicol ; 41(3): 249-258, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28925291

RESUMO

Moringa oleifera is reported to be a miracle plant, with positive effects on practically every system in the animal body. The methanolic extract of Moringa oleifera leaves was fractionated using liquid-liquid fractionation, column chromatography and preparative high-performance liquid chromatography (HPLC). Bioassay guided fractionation using Ferric Reducing Antioxidant Power (FRAP) was used to determine the fraction with the highest antioxidative power. Chemical structure was elucidated with nuclear magnetic resonance (NMR) spectroscopy. FRAP showed that the pure compound, butyl p-hydroxyphenyl-acetate (MIMO2) exhibited an antioxidant activity higher than TEMPOL (positive control). Vanadium is a metal, which as a salt has been shown to be a neurotoxicant; and was therefore used to assess the efficacy of MIMO2 in this experiment. HT22 (immortalized mouse hippocampal) cells were used for cell culture. The Comet assay showed a statistically significant reduction (p < .05) in DNA damage when 0.25 and 0.5 µM MIMO2 as well as 0.1 and 0.2 mg of the methanolic extract of Moringa oleifera leaves (MO) were used in combination with 200 µM vanadium (sodium metavanadate). Analogously, a reduced formation of superoxide was observed using dihydroethidium (2,7-Diamino-10-ethyl-9-phenyl-9,10-dihydrophenanthridine-DHE) stain after 0.5 µM MIMO2 and 0.063 mg MO were used in combination with vanadium 100 µM. MIMO2 and MO gave a statistically significant (p < .05) protective effect against vanadium toxicity on neuronal cells. Further assays may need to be performed to assess the extent of protection that MIMO2 may offer, and also to better understand its mechanisms of action.


Assuntos
Antioxidantes/isolamento & purificação , Moringa oleifera/química , Extratos Vegetais/análise , Folhas de Planta/química , Vanádio/toxicidade , Animais , Antioxidantes/farmacologia , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Citoproteção , Dano ao DNA , Camundongos , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo
5.
PLoS One ; 10(11): e0142386, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26554591

RESUMO

Human leishmaniasis covers a broad spectrum of clinical manifestations ranging from self-healing cutaneous leishmaniasis to severe and lethal visceral leishmaniasis caused among other species by Leishmania major or Leishmania donovani, respectively. Some drug candidates are in clinical trials to substitute current therapies, which are facing emerging drug-resistance accompanied with serious side effects. Here, two cinnamic acid bornyl ester derivatives (1 and 2) were assessed for their antileishmanial activity. Good selectivity and antileishmanial activity of bornyl 3-phenylpropanoate (2) in vitro prompted the antileishmanial assessment in vivo. For this purpose, BALB/c mice were infected with Leishmania major promastigotes and treated with three doses of 50 mg/kg/day of compound 2. The treatment prevented the characteristic swelling at the site of infection and correlated with reduced parasite burden. Transmitted light microscopy and transmission electron microscopy of Leishmania major promastigotes revealed that compounds 1 and 2 induce mitochondrial swelling. Subsequent studies on Leishmania major promastigotes showed the loss of mitochondrial transmembrane potential (ΔΨm) as a putative mode of action. As the cinnamic acid bornyl ester derivatives 1 and 2 had exhibited antileishmanial activity in vitro, and compound 2 in Leishmania major-infected BALB/c mice in vivo, they can be regarded as possible lead structures for the development of new antileishmanial therapeutic approaches.


Assuntos
Antiprotozoários/uso terapêutico , Cinamatos/uso terapêutico , Leishmaniose/tratamento farmacológico , Fígado/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/uso terapêutico , Valeriana , Animais , Antiprotozoários/farmacologia , Cinamatos/farmacologia , Feminino , Leishmania , Fígado/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/farmacologia
6.
Molecules ; 20(6): 10873-83, 2015 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-26076109

RESUMO

Bornyl caffeate (1) was previously isolated by us from Valeriana (V.) wallichii rhizomes and identified as an anti-leishmanial substance. Here, we screened a small compound library of synthesized derivatives 1-30 for activity against schistosomula of Schistosoma (S.) mansoni. Compound 1 did not show any anti-schistosomal activity. However, strong phenotypic changes, including the formation of vacuoles, degeneration and death were observed after in vitro treatment with compounds 23 (thymyl cinnamate) and 27 (eugenyl cinnamate). Electron microscopy analysis of the induced vacuoles in the dying parasites suggests that 23 and 27 interfere with autophagy.


Assuntos
Cinamatos/química , Cinamatos/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Esquistossomicidas/química , Esquistossomicidas/farmacologia , Animais , Vesículas Citoplasmáticas , Avaliação Pré-Clínica de Medicamentos , Ésteres , Schistosoma mansoni/citologia , Schistosoma mansoni/ultraestrutura , Bibliotecas de Moléculas Pequenas
7.
Molecules ; 20(4): 5740-53, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25834987

RESUMO

The chloroform extract of Valeriana wallichii (V. wallichii) rhizomes was investigated to elucidate the structures responsible for reported antileishmanial activity. Besides bornyl caffeate (1, already been reported by us previously), bioassay-guided fractionation resulted in two additional cinnamic acid derivatives 2-3 with moderate leishmanicidal activity. The structure of a novel nepetolactone derivative 4 having a cinnamic acid moiety was elucidated by means of spectral analysis. To the best of our knowledge villoside aglycone (5) was isolated from this plant for the first time. The bioassay-guided fractionation yielded two new (compounds 6-7) and two known valtrates (compounds 8-9) with leishmanicidal potential against Leishmania major (L. major) promastigotes. In addition, ß-bisabolol (10), α-kessyl alcohol (11), valeranone (12), bornyl isovalerate (13) and linarin-2-O-methylbutyrate (14) were identified. This is the first report on the isolation of 4'-demethylpodophyllotoxin (15), podophyllotoxin (16) and pinoresinol (17) in V. wallichii. In total thirteen known and four new compounds were identified from the extract and their cytotoxic and antileishmanial properties were evaluated.


Assuntos
Antiprotozoários/farmacologia , Leishmania major/efeitos dos fármacos , Extratos Vegetais/farmacologia , Valeriana/química , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Extratos Vegetais/química , Sesquiterpenos Policíclicos , Rizoma/química , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação
8.
Molecules ; 19(2): 1394-410, 2014 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-24473204

RESUMO

Bioassay-guided fractionation of a chloroform extract of Valeriana wallichii (V. wallichii) rhizomes lead to the isolation and identification of caffeic acid bornyl ester (1) as the active component against Leishmania major (L. major) promastigotes (IC50 = 48.8 µM). To investigate the structure-activity relationship (SAR), a library of compounds based on 1 was synthesized and tested in vitro against L. major and L. donovani promastigotes, and L. major amastigotes. Cytotoxicity was determined using a murine J774.1 cell line and bone marrow derived macrophages (BMDM). Some compounds showed antileishmanial activity in the concentration range of pentamidine and miltefosine which are the standard drugs in use. In the L. major amastigote assay compounds 15, 19 and 20 showed good activity with relatively low cytotoxicity against BMDM, resulting in acceptable selectivity indices. Molecules with adjacent phenolic hydroxyl groups exhibited elevated cytotoxicity against murine cell lines J774.1 and BMDM. The Michael system seems not to be essential for antileishmanial activity. Based on the results compound 27 can be regarded as new lead structure for further structure optimization.


Assuntos
Antiprotozoários/química , Ácidos Cafeicos/química , Leishmaniose/tratamento farmacológico , Relação Estrutura-Atividade , Animais , Antiprotozoários/síntese química , Ácidos Cafeicos/síntese química , Ácidos Cafeicos/farmacologia , Humanos , Leishmania donovani/efeitos dos fármacos , Leishmania major/efeitos dos fármacos , Leishmaniose/parasitologia , Camundongos , Valeriana/química
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