References of "Tits, Monique"
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See detailEthnopharmacologie et paludisme au Burkina Faso : sélection de 13 espèces à potentialités antiplasmodiales méconnues
Jansen, Olivia ULg; Frederich, Michel ULg; Tits, Monique ULg et al

in Ethnopharmacologia (2008), 41

Dans la recherche de nouvelles substances actives contre les Plasmodium, les flores non explorées du Sud constituent une source potentielle privilégiée de nouveaux médicaments antipaludéens. Dans ce ... [more ▼]

Dans la recherche de nouvelles substances actives contre les Plasmodium, les flores non explorées du Sud constituent une source potentielle privilégiée de nouveaux médicaments antipaludéens. Dans ce travail, nous avons suivi une démarche ethnopharmacologique afin de répertorier et de sélectionner des végétaux intéressants à étudier en laboratoire pour leurs propriétés antiplasmodiales. Notre travail de recensement des espèces utilisées contre la malaria au Burkina Faso nous a permis de répertorier 72 espèces végétales utilisées seules ou en association dans le traitement traditionnel du paludisme dans ce pays d’Afrique de l’Ouest. Finalement, treize espèces ont été sélectionnées et dix-sept échantillons végétaux ont été récoltés au Burkina Faso pour évaluation de leurs propriétés antiplasmodiales en laboratoire. Les principaux critères de sélection ont été : leur utilisation traditionnelle contre la malaria et le fait que ces plantes n’aient pas (ou peu) été étudiées sur le plan antiplasmodial. Les liens de chimiotaxonomie éventuels avec des plantes déjà connues pour leurs propriétés antiplasmodiales ainsi que les possibilités de valorisation des espèces au niveau local (MTA) ont également été considérés. [less ▲]

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See detailPotential antimalarial activity of indole alkaloids
Frederich, Michel ULg; Tits, Monique ULg; Angenot, Luc ULg

in Transactions of the Royal Society of Tropical Medicine & Hygiene (2008), 102(1), 11-19

New antimalarial treatments are now urgently required, following the emergence of resistance to the most used drugs. Natural products contribute greatly to the therapeutic arsenal in this area, including ... [more ▼]

New antimalarial treatments are now urgently required, following the emergence of resistance to the most used drugs. Natural products contribute greatly to the therapeutic arsenal in this area, including artemisinin and quinine (and atovaquone, semi-synthetic). Among the natural products, indole alkaloids represent an interesting class of compounds. Screening carried out to date has revealed several substances active in vitro under the micromolar range and with a good selectivity index. This review covers the indole alkaloids with high antiplasmodial activity (in vitro and in vivo) isolated from natural sources, and is organized according to the different chemical structures of the alkaloids. [less ▲]

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See detailIn vitro antiplasmodial activity of ethnobotanically selected plants from Burkina Faso
Jansen, Olivia ULg; Angenot, Luc ULg; Tits, Monique ULg et al

in Planta Medica (2008), 74(9), 1142-1142

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See detailIn vitro cytotoxicity of some medicinal plants from Georgian amaryllidaceae
Jokhadze, Malkhaz; Eristavi, Lina; Kutchukhidze, Jumber et al

in Phytotherapy Research (2007), 21(7), 622-624

Using an ethnomedical data approach, some Georgian plants, which are used in Georgian traditional medicine for cancer or non-cancer diseases, were collected and evaluated for cytotoxic activity. The ... [more ▼]

Using an ethnomedical data approach, some Georgian plants, which are used in Georgian traditional medicine for cancer or non-cancer diseases, were collected and evaluated for cytotoxic activity. The cytotoxic effect of the methanol extracts of species from the genera Galanthus and Leucojum was evaluated in vitro on three human cell lines (Hela, ephitheloid cervix carcinoma; HCT-116, colon carcinoma; HL-60, acute myeloid leukaemia). Cell type cytotoxic specificity was observed for some extracts. Overall, the HCT-116 cells were much more sensitive to most of the extracts than were the other cell lines. Plants that showed pronounced cytotoxic activity will be further evaluated for the possible isolation of active antitumour compounds. Copyright (C) 2007 John Wiley [less ▲]

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See detailCharacterization of the neurotoxicity induced by the extract of Magnistipula butayei (Chrysobalanaceae) in rat: Effects of a new natural convulsive agent
Karangwa, Charles; Esters, Virginie ULg; Tits, Monique ULg et al

in Toxicon (2007), 49(8), 1109-1119

This study was designed to document convulsant and neurotoxic properties of extracts of a tropical tree, Magnistipula butayei subsp. Montana, and to investigate the involvement of the glutamatergic system ... [more ▼]

This study was designed to document convulsant and neurotoxic properties of extracts of a tropical tree, Magnistipula butayei subsp. Montana, and to investigate the involvement of the glutamatergic system in these effects. Continuous behavioral observations and electroencephalographic (EEG) records were obtained after per os administration of an aqueous extract of Magnistipula (MBMAE) in rats. MBMAE (800 mg/kg) induced behavioral changes resembling motor limbic seizures: staring and head tremor, automatisms, forelimb clonic movements and violent tonic-clonic seizures leading to death in all animals. Concomitantly, important seizure activity that gradually evolved to epileptiform activity was recorded on the EEG. Moreover, c-Fos immunohistochemistry has revealed an increased c-Fos expression in the dentate gyrus and in piriform, peri- and entorhinal cortices 2 and 4h after treatment. This expression pattern suggested that the mechanism of action for the MBMAE is similar to that observed in glutamate-induced models of epilepsy. The MBMAE increased cell death also in hippocampal cell cultures. Furthermore, the build-up of convulsive activity and epileptic discharges induced by MBMAE in rat were abolished by MK-801, an NMDA receptor antagonist. Our study suggests that MBMAE contains a potent toxin, with a powerful neurotoxic activity in rat, and corresponding to a new natural component(s) that act as an NMDA-mediated convulsant molecule. [less ▲]

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See detailIn vivo antimalarial activity of isosungucine, an indolomonoterpenic alkaloid from Strychnos icaja
Philippe, Geneviève ULg; De Mol, Patrick ULg; Angenot, Luc ULg et al

in Planta Medica (2007), 73(5), 478-479

Isosungucine (1) is a quasi-symmetric bisindolomonoterpenoid alkaloid isolated from the roots of Strychnos icaja. The in vivo antimalarial activity against the P. vinckei petteri murine strain was ... [more ▼]

Isosungucine (1) is a quasi-symmetric bisindolomonoterpenoid alkaloid isolated from the roots of Strychnos icaja. The in vivo antimalarial activity against the P. vinckei petteri murine strain was determined. In the Peters 4-day suppressive test, 1 suppressed the parasitemia by almost 50 percent on day 4 at the dose of 30 mg/kg by intraperitoneal route. [less ▲]

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See detailPotentialités antipaludiques des alcaloïdes indoliques
Frederich, Michel ULg; Philippe, Geneviève ULg; Tits, Monique ULg et al

in Actualités de Chimie Thérapeutique (2007), 33

This paper will be mainly illustrated with references to selected antiplasmodial compounds:- indole alkaloid analogues of emetine isolated from Strychnos usambarensis and Pogonopus tubulosus-other ... [more ▼]

This paper will be mainly illustrated with references to selected antiplasmodial compounds:- indole alkaloid analogues of emetine isolated from Strychnos usambarensis and Pogonopus tubulosus-other bisindole alkaloids isolated from Loganiacea and Apocynaceae -indoloquinolines (cryptolepine and analogues) -indolo quinazoline-6,12-diones and derivatives from Strobilanthes and other sources -aminopolycyclic beta-carbolines ( manzamines) !solated from Indo-Pacific sponges. The paper will be finally also focused on the design of chemosensitizers that are capable of reversing in vitro chloroquine resistance( case of some mono-indole alkaloids). [less ▲]

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See detailValidation of a high-performance thin-layer chromatography/densitometry method for the quantitative determination of glucosamine in a herbal dietary supplement
Esters, Virginie ULg; Angenot, Luc ULg; Brandt, V. et al

in Journal of Chromatography. A (2006), 1112(1-2), 156-164

A quantitative densitometric high-performance thin-layer chromatography (HPTLC) method was developed for the determination of glucosamine in a dietary supplement containing dried extracts of the main ... [more ▼]

A quantitative densitometric high-performance thin-layer chromatography (HPTLC) method was developed for the determination of glucosamine in a dietary supplement containing dried extracts of the main plants traditionally used for rheumatic disorders. The HPTLC method was chosen in order to circumvent the tedious and time-consuming sample preparation steps necessarily performed before using HPLC methods when analysing complex matrixes. Glucosamine was separated from the plant extracts on a silica gel 60 F(254) HPTLC plate using a saturated mixture of 2-propanol-ethyl acetate-ammonia solution (8%) (10:10:10, v/v/v). The plates were developed vertically up to a distance of 80 mm. For visualization, the plate was dipped into a modified anisaldehyde reagent and heated at 120 degrees C for 30 min in a drying oven. Glucosamine appeared as brownish-red chromatographic zones on a colourless background. Densitometric quantification was performed at lambda = 415 nm by reflectance scanning. The HPTLC method was successfully validated by applying the novel validation protocol proposed by a commission of the "Societe Francaise des Sciences et Techniques Pharmaceutiques" (SFSTP). In the pre-validation phase, the appropriate response function was determined, while in the validation phase the method showed good performance thereby fulfilling its objective of quantifying accurately. The relative standard deviations for repeatability and intermediate precision were between 4.9 and 8.6%. Moreover, the method was found to be accurate, as the two-sided 95% beta-expectation tolerance interval did not exceed the acceptance limits of 85 and 115% on the whole analytical range (800-1,200 ng of glucosamine). [less ▲]

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See detailScreening of 14 alkaloids isolated from Haplophyllum A. Juss. for their cytotoxic properties
Jansen, Olivia ULg; Akhmedjanova, Valentina; Angenot, Luc ULg et al

in Journal of Ethnopharmacology (2006), 105(1-2), 241-245

Further to a systematic chemotaxonomic study of Uzbek Haplophyllum A. Juss. plants selected on ethnopharmacological data, 14 alkaloids were screened for their cytotoxic properties. As a first selection ... [more ▼]

Further to a systematic chemotaxonomic study of Uzbek Haplophyllum A. Juss. plants selected on ethnopharmacological data, 14 alkaloids were screened for their cytotoxic properties. As a first selection for interesting compounds, each alkaloid was tested against two human cancer cell lines (HeLa and HCT-116), using WST-1 reagent. Of the 14 alkaloids, 5 were cytotoxic when tested against the HeLa line with an IC50 < 100 microM. These five compounds consisted of three furoquinolines: skimmianine; haplopine and gamma-fagarine and two pyranoquinolones: flindersine and haplamine. Only haplamine was active against the HCT-116 line. The cytotoxic properties of these five alkaloids were further investigated against five additional human cancer cell lines. Their structure-activity relationships will be discussed. Of these five pre-selected alkaloids, only haplamine showed significant cytotoxic activity against all the tested cell lines. This is the first report of the cytotoxic activity of haplamine. Finally, this pyranoquinolone alkaloid was tested here against 14 different cancer cell lines and against normal skin fibroblasts. [less ▲]

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See detailStudy of the interaction of antiplasmodial strychnine derivatives with the glycine receptor
Philippe, Geneviève ULg; Nguyen, Laurent ULg; Angenot, Luc ULg et al

in European Journal of Pharmacology (2006), 530(1-2), 15-22

Strychnos icaja Baill. (Loganiaccae) is a liana found in Central Africa known to be an arrow and ordeal poison but also used by traditional medicine to treat malaria. Recently, many dimeric or trimeric ... [more ▼]

Strychnos icaja Baill. (Loganiaccae) is a liana found in Central Africa known to be an arrow and ordeal poison but also used by traditional medicine to treat malaria. Recently, many dimeric or trimeric indolomonoterpenic alkaloids with antiplasmodial properties have been isolated from its rootbark. Since these alkaloids are derivatives of strychnine, it was important, in view of their potential use as antimalarial drugs, to assess their possible convulsant strychnine-like properties. In that regard, their interaction with the strychnine-sensitive glycine receptor was investigated by whole-cell patch-clamp recordings on glycine-gated currents in mouse spinal cord neurons in culture and by [H-3]strychnine competition assays on membranes from adult rat spinal cord. These experiments were carried out on sungucine (leading compound of the chemical class) and on the antiplasmodial strychnogucine B (dimeric) and strychnohexamine (trimeric). In comparison with strychnine, all compounds interact with a very poor efficacy and only at concentrations > I mu M with both [H-3]strychnine binding and glycine-gated currents. Furthermore, the effects of strychnine and protostrychnine, a monomeric alkaloid (without antiplasmodial activity) also isolated from S. icaja and differing from strychnine only by a cycle opening, were compared in the same way. The weak interaction of protostrychnine confirms the importance of the G cycle ring structure in strychnine for its binding to the glycine receptor and its antagonist properties. (c) 2005 Elsevier B.V. All rights reserved. [less ▲]

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See detailIn vitro screening of some Strychnos species for antiplasmodial activity
Philippe, Geneviève ULg; Angenot, Luc ULg; De Mol, Patrick ULg et al

in Journal of Ethnopharmacology (2005), 97(3), 535-539

The antiplasmodial activity of crude extracts of 19 species of Strychnos (Loganiaceae) was assessed in vitro against a chloroquine-susceptible strain of Plasmodium falciparum. For each species, ethyl ... [more ▼]

The antiplasmodial activity of crude extracts of 19 species of Strychnos (Loganiaceae) was assessed in vitro against a chloroquine-susceptible strain of Plasmodium falciparum. For each species, ethyl acetate (EtOAc) extracts were analysed and, for the most active species, methanolic (MeOH) extracts were also tested. Among them, Strychnos variabilis De Wild. seemed to be very promising (inhibitory concentration 50% (IC50) < 5 microg/ml) whereas two other species, Strychnos gossweileri Exell and Strychnos mellodora S. Moore, could be interesting (IC50 < 15 microg/ml) in further antimalarial studies. [less ▲]

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See detailInhibitory Effects of Proanthocyanidins from Ribes Nigrum Leaves on Carrageenin Acute Inflammatory Reactions Induced in Rats
Garbacki, Nancy ULg; Tits, Monique ULg; Angenot, Luc ULg et al

in BMC Pharmacology (2004), 4(1), 1-9

BACKGROUND: The anti-inflammatory effects of proanthocyanidins (PACs), isolated from blackcurrant (Ribes nigrum L.) leaves, were analysed using carrageenin-induced paw oedema and carrageenin-induced ... [more ▼]

BACKGROUND: The anti-inflammatory effects of proanthocyanidins (PACs), isolated from blackcurrant (Ribes nigrum L.) leaves, were analysed using carrageenin-induced paw oedema and carrageenin-induced pleurisy in rats. RESULTS: Pretreatment of the animals with PACs (10, 30, 60 and 100 mg/kg, i.p.) reduced paw oedema induced by carrageenin in a dose and time-dependent manner. PACs also inhibited dose-dependently carrageenin-induced pleurisy in rats. They reduced (A) lung injury, (B) pleural exudate formation, (C) polymorphonuclear cell infiltration, (D) pleural exudate levels of TNF-alpha, IL-1beta and CINC-1 but did not affect IL-6 and IL-10 levels. They reduced (E) pleural exudate levels of nitrite/nitrate (NOx). In indomethacin treated rats, the volume of pleural exudate was low, its content in leukocytes and its contents in TNF-alpha, IL-1beta, IL-6 and IL-10 but not in NOx were reduced. These data suggest that the anti-inflammatory properties of PACs are achieved through a different pattern from those of indomethacin. CONCLUSION: These results suggest that the main mechanism of the anti-inflammatory effect of PACs mainly lies in an interference with the migration of the leukocytes. Moreover, PACs inhibited in vivo nitric oxide release. [less ▲]

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See detailAbout the toxicity of some Strychnos species and their alkaloids
Philippe, Geneviève ULg; Angenot, Luc ULg; Tits, Monique ULg et al

in Toxicon (2004), 44(4), 405-416

Poisons are widespread in plants and animals and humankind has often tried to turn them to its own advantage. Owing to their poisonous properties, some species of Strychnos genus have been employed mainly ... [more ▼]

Poisons are widespread in plants and animals and humankind has often tried to turn them to its own advantage. Owing to their poisonous properties, some species of Strychnos genus have been employed mainly in hunting and fishing, as an adjunct to weapons used not only in the search of food and clothes, but also for preventing depredation by wild animals. They have been employed for martial and criminal purposes and also as a means of determining guilt or innocence. By their nature, poisons such as strychnine and curate affect the functioning of the victim's body; this also means that they have been, and are, an important source of pharmacological tools and medicines all over the world. With such potentially dangerous substances, care in medication is essential to avoid complications by overdose. All these points are approached in the present review. (C) 2004 Elsevier Ltd. All rights reserved. [less ▲]

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See detailIn vitro and in vivo antimalarial properties of isostrychnopentamine, an indolomonoterpenic alkaloid from Strychnos usambarensis
Frederich, Michel ULg; Tits, Monique ULg; Goffin, Eric ULg et al

in Planta Medica (2004), 70(6), 520-525

Isostrychnopentamine (ISP) is an asymmetric indolomonoterpenic alkaloid isolated from the leaves of Strychnos usambarensis. The in vitro antiplasmodial activities against five Plasmodium falciparum cell ... [more ▼]

Isostrychnopentamine (ISP) is an asymmetric indolomonoterpenic alkaloid isolated from the leaves of Strychnos usambarensis. The in vitro antiplasmodial activities against five Plasmodium falciparum cell lines were evaluated: ISP possessed an in vitro IC (50) near 0.1 microM against all P. falciparum cell lines tested (chloroquine-resistant and chloroquine-sensitive lines) and showed antiplasmodial selectivity compared to cytotoxicity on human cell lines. The stage-dependent susceptibility to a short exposure of ISP was then investigated. The ring stage was shown to be the most sensitive one, but all stages were affected by ISP treatment. By means of fluorescence microscopy, it was shown that ISP was not accumulated inside the food vacuole of the parasite. Finally, the in vivo antimalarial activities against the P. berghei NK173 and P. vinckei petteri murine strains were determined. The ED (50) in vivo was about 30 mg/kg/day by the intraperitoneal route (after 4 days treatment). [less ▲]

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See detailLC/MS/NMR analysis of isomeric divanilloylquinic acids from the root bark of Fagara zanthoxyloides Lam
Ouattara, Badiore; Angenot, Luc ULg; Guissou, Pierre et al

in Phytochemistry (2004), 65(8), 1145-1151

Gradient HPLC coupled to DAD/UV, MS/MS and NMR has been applied to the rapid structure determination of three new isomeric divanilloylquinic acids from Fagara zanthoxyloides collected in Burkina Faso: 3,4 ... [more ▼]

Gradient HPLC coupled to DAD/UV, MS/MS and NMR has been applied to the rapid structure determination of three new isomeric divanilloylquinic acids from Fagara zanthoxyloides collected in Burkina Faso: 3,4-O-divanilloylquinic acid, 3,5-O-divanilloylquinic acid and 4,5-O-divanilloylquinic acid. Furthermore these new compounds named burkinabins A-C could play a useful role in sickle cell disease, as the active agents of Fagara zanthoxyloides are said to be unidentified aromatic compounds with carboxylic acid grouping (Adesanya, S.A., Sofowora, A., 1983. Biological standardisation of Zanthoxylum roots for antisickling activity. Planta Med. 48, 27-33). (C) 2004 Elsevier Ltd. All rights reserved. [less ▲]

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See detailChrysopentamine, an antiplasmodial anhydronium base from Strychnos usambarensis leaves
Frederich, Michel ULg; Cristino, Assunção; Choi, Young Hae et al

in Planta Medica (2004), 70(1), 72-76

A new derivative of strychnopentamine was isolated from the leaves of Strychnos usambarensis. This compound, named chrysopentamine, was identified by detailed spectroscopic methods (UV, IR, HR-ESI-MS, 1D ... [more ▼]

A new derivative of strychnopentamine was isolated from the leaves of Strychnos usambarensis. This compound, named chrysopentamine, was identified by detailed spectroscopic methods (UV, IR, HR-ESI-MS, 1D and 2D NMR). Chrysopentamine presented an original hydroxy substitution on C-14 and an aromatization of the ring D of strychnopentamine leading to anhydronium base proper-ties and exhibited strong antiplasmodial properties (IC50 less than 1 muM). [less ▲]

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See detailA HPTLC densitometric determination of flavonoids from Passiflora alata, P-edulis, P-incarnata and P-caerulea and comparison with HPLC method
Pereira, C. A. M.; Yariwake, J. H.; Lancas, F. M. et al

in Phytochemical Analysis [=PCA] (2004), 15(4, JUL-AUG), 241-248

A high-performance thin layer chromatographic (HPTLC) method was developed in order to determine quantitatively the flavonoids in leaves of Passiflora alata, P. edulis, P. caerulea and P. incarnata. The ... [more ▼]

A high-performance thin layer chromatographic (HPTLC) method was developed in order to determine quantitatively the flavonoids in leaves of Passiflora alata, P. edulis, P. caerulea and P. incarnata. The content of orientin and isoorientin was determined, and the results were compared with those obtained using a quantitative HPLC-UV method. The latter employed rutin as standard and was developed to analyse flavonoid content from Passiflora leaves for the purpose of ensuring the quality of Passiflora phytomedicines. The results obtained using the two methods indicate that there are qualitative and quantitative differences in the flavonoids of the reference Passiflora species studied. The two methods were also employed to analyse commercial samples to illustrate their application in qualitative ('fingerprint') and quantitative determination, demonstrating their feasibility in the quality control of flavonoids from crude Passiflora drugs and phytomedicines. The HPLC conditions used are also suitable for the quantitative analysis of aqueous extracts (Passiflora infusions). Copyright (C) 2004 John Wiley Sons, Ltd. [less ▲]

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See detailQuantification of tagitinin C in Tithonia diversifolia by reversed-phase high-performance liquid chromatography.
Goffin, Eric ULg; da Cunha, Antonio Proenca; Ziemons, Eric ULg et al

in Phytochemical Analysis [=PCA] (2003), 14(6), 378-80

A simple, rapid and reliable reversed-phase high-performance liquid chromatographic method for the determination of tagitinin C, an anti-plasmodial sesquiterpene lactone isolated from the aerial parts of ... [more ▼]

A simple, rapid and reliable reversed-phase high-performance liquid chromatographic method for the determination of tagitinin C, an anti-plasmodial sesquiterpene lactone isolated from the aerial parts of Tithonia diversifolia, has been developed. The assay has been used to quantify tagitinin C in various extracts of the aerial parts of T. diversifolia. [less ▲]

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