References of "Angenot, Luc"
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See detailActivités cytotoxiques et apoptotiques de gigantéosides D et E isolés de Cephalaria gigantea
Gerkens, Pascal; Frederich, Michel ULg; Mshvildadze, Vakhtang et al

Poster (2002, September)

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See detailNew trends in anti-malarial agents
Frederich, Michel ULg; Dogné, Jean-Michel ULg; Angenot, Luc ULg et al

in Current Medicinal Chemistry (2002), 9(15), 1435-1456

Malaria is the major parasitic infection in many tropical and subtropical regions, leading to more than one million deaths (principally young African children) out of 400 million cases each year (WHO ... [more ▼]

Malaria is the major parasitic infection in many tropical and subtropical regions, leading to more than one million deaths (principally young African children) out of 400 million cases each year (WHO world health report 2000). More than half of the world's population live in areas where they remain at risk of malaria infection. During last years, the situation has worsened in many ways, mainly due to malarial parasites becoming increasingly resistant to several antimalarial drugs. Furthermore, the control of malaria is becoming more complicated by the parallel spread of resistance of the mosquito vector to currently available insecticides. Discovering new drugs in this field is therefore a health priority. Several new molecules are under investigation. This review describes the classical treatments of malaria and the latest discoveries in antimalarial agents, especially artemisinin and its recent derivatives as well as the novel peroxidic compounds. [less ▲]

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See detailApoptosis of HL-60 leukemia cells induced by the bisindole alkaloids sungucine and isosungucine from Strychnos icaja
Lansiaux, A.; Bailly, Christian; Houssier, Claude ULg et al

in Planta Medica (2002), 68(7), 591-595

Sungucine and isosungucine are two bisindole alkaloids isolated from the roots of the African plant Strychnos icaja Baillon. They both exhibit antiplasmodial activities but also show cytotoxic effects ... [more ▼]

Sungucine and isosungucine are two bisindole alkaloids isolated from the roots of the African plant Strychnos icaja Baillon. They both exhibit antiplasmodial activities but also show cytotoxic effects against human cancer cell lines. In order to elucidate their mechanism of action, we have investigated the interaction of the alkaloids with DNA and their capacity to inhibit nucleic acids and protein synthesis in the human HL-60 promyelocytic leukemia cell line. Cell treatment with both sungucine and isosungucine leads to the appearance of a hypo-diploid DNA content peak. Western blotting analysis reveals that the two alkaloids induce cleavage of the poly(ADP-ribose) polymerase (PARP) and promote the cleavage of a caspase-3 DEVD peptide substrate. The activation of the caspase cascade is accompanied with a fragmentation of DNA in cells, as revealed by the TUNEL assay. Altogether, the results shed light on the mechanism of action of these two plant alkaloids and identify signaling factors involved in (iso)sungucine-induced apoptosis in HL-60 cells. [less ▲]

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See detailEffects of prodelphinidins isolated from Ribes nigrum on chondrocyte metabolism and COX activity
Garbacki, Nancy ULg; Angenot, Luc ULg; Bassleer, C. et al

in Naunyn-Schmiedeberg's Archives of Pharmacology (2002), 365(6), 434-441

Articular diseases. such as osteoarthritis, is the clinical expression of the loss of cartilage function. COX inhibitors are widely used in the treatment of such pathologies for their beneficial effects ... [more ▼]

Articular diseases. such as osteoarthritis, is the clinical expression of the loss of cartilage function. COX inhibitors are widely used in the treatment of such pathologies for their beneficial effects on inflammation but often produce a negative activity on cartilage synthesis. In this study, we determined the effect of different prodelphinidins, the major compounds isolated from Ribes nigrum leaves, on the proteoglycans (PGs), type II collagen (coll. II) and prostaglandin E-2 (PGE(2)) production by differentiated human chondrocytes cultivated in long term (12 days) and in clusters as well as their inhibition potential on COX-1 and COX-2 in vitro. Gallocatechin trimer (GC-GC-GC) showed the higher stimulation of PGs and coll. II production (1 mug ml(-1)) and the synthesis of PGE(2) was significantly reduced by gallocatechin dimer (GC-GC), gallocatechin-epigallocatechin (GC-EGC) and GC-GC-GC at 10 and 100 mug ml(-1). The inhibition of PGE(2) synthesis was confirmed by the in vitro test on purified COX enzymes, showing the selectivity of prodelphinidins on COX-2. However, the prodelphinidins had no effects on COX activity in the whole blood assay. Our studies suggest that the prodelphinidins fractions from R. nigrum may be useful as an additive agent in the prevention of osteoarthritis. [less ▲]

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See detailIn vitro antiplasmodial activity of Tithonia diversifolia and identification of its main active constituent: tagitinin C.
Goffin, Eric ULg; Ziemons, Eric ULg; De Mol, Patrick ULg et al

in Planta Medica (2002), 68(6), 543-5

The antimalarial properties of Tithonia diversifolia, an Asteraceae traditionally used to treat malaria, were investigated in vitro against three strains of Plasmodium falciparum. The ether extract from ... [more ▼]

The antimalarial properties of Tithonia diversifolia, an Asteraceae traditionally used to treat malaria, were investigated in vitro against three strains of Plasmodium falciparum. The ether extract from aerial parts of the plant collected in Sao Tome e Principe, demonstrated good antiplasmodial activity (IC 50 on FCA strain: 0.75 microg/ml). A bioassay guided fractionation of this extract led to the isolation of the known sesquiterpene lactone tagitinin C as an active component against Plasmodium (IC 50 on FCA strain: 0.33 microg/ml), but also possessing cytotoxic properties (IC 50 on HTC-116 cells: 0.706 microg/ml). [less ▲]

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See detailStrychnohexamine from Strychnos icaja, a naturally occurring trimeric indolomonoterpenic alkaloid
Philippe, Geneviève ULg; Prost, E.; Nuzillard, J. M. et al

in Tetrahedron Letters (2002), 43(18), 3387-3390

A reinvestigation of Strychnos icaja roots has resulted in the isolation, from the EtOAC extract, of one tertiary trisindole alkaloid, named strychnohexamine. Its structure has been investigated by means ... [more ▼]

A reinvestigation of Strychnos icaja roots has resulted in the isolation, from the EtOAC extract, of one tertiary trisindole alkaloid, named strychnohexamine. Its structure has been investigated by means of spectroscopic data interpretation (UV. IR. HRESIMS. 1D and 2D NMR). This is the first time that a natural trimeric indolomonoterpenic alkaloid has been isolated directly from a plant species. This compound is one of the largest alkaloids ever discovered. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailNew 3-deoxyanthocyanidins from leaves of Arrabidaea chica
Devia, B.; Llabres, Gabriel ULg; Wouters, J. et al

in Phytochemical Analysis (2002), 13(2, Mar-Apr), 114-120

Two new 3-deoxyanthocyanidins, 6,7,3',4'-tetrahydroxy-5-methoxyflavylium and 6,7,4'-trihydroxy-5-methoxyflavylium, and the pigment carajurin, which has been previously identified, were isolated from dried ... [more ▼]

Two new 3-deoxyanthocyanidins, 6,7,3',4'-tetrahydroxy-5-methoxyflavylium and 6,7,4'-trihydroxy-5-methoxyflavylium, and the pigment carajurin, which has been previously identified, were isolated from dried leaves of Arrabidaea chica, a creeper native to the American tropics. The structures of the components were elucidated by H-1- and C-13-NMR spectroscopy and HPLC-MS, including X-ray crystallographic analysis for carajurin. Copyright (C) 2002 John Wiley Sons, Ltd. [less ▲]

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See detail5',6'-Dehydroguiachrysine and 5',6'-Dehydroguiaflavine, Two Curarizing Quaternary Indole Alkaloids from the Stem Bark of Strychnos Guianensis
Penelle, J.; Christen, P.; Molgo, J. et al

in Phytochemistry (2001), 58(4), 619-26

Two new quaternary indole alkaloids 5',6'-dehydroguiachrysine (1) and 5',6'-dehydroguiaflavine (2) were isolated from Strychnos guianensis stem bark. Their structures were determined by analysis of ... [more ▼]

Two new quaternary indole alkaloids 5',6'-dehydroguiachrysine (1) and 5',6'-dehydroguiaflavine (2) were isolated from Strychnos guianensis stem bark. Their structures were determined by analysis of spectral data. Their inhibitory effects on neuromuscular transmission are also reported and compared to that of other quaternary alkaloids. [less ▲]

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See detailA propos des remèdes végétaux à visée amaigrissante
Angenot, Luc ULg

Article for general public (2001)

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See detailReversal of Chloroquine and Mefloquine Resistance in Plasmodium Falciparum by the Two Monoindole Alkaloids, Icajine and Isoretuline
Frederich, Michel ULg; Hayette, Marie-Pierre ULg; Tits, Monique ULg et al

in Planta Medica (2001), 67(6), 523-7

Eight naturally occurring monoindole alkaloids were evaluated in vitro for their ability to inhibit Plasmodium falciparum growth and, in drug combination, to reverse the resistance of a chloroquine ... [more ▼]

Eight naturally occurring monoindole alkaloids were evaluated in vitro for their ability to inhibit Plasmodium falciparum growth and, in drug combination, to reverse the resistance of a chloroquine-resistant strain of Plasmodium falciparum. None of these indole alkaloids has significant intrinsic antiplasmodial activity (IC(50) > 10 microM or 5 microg/ml). Nevertheless, three alkaloids (icajine, isoretuline and strychnobrasiline) did reverse chloroquine resistance at concentrations between 2.5 and 25 microg/ml (IF of 12.82 for isoretuline on W2 strain). The Interaction Factor (IF) equals 2, < 2, or > 2 for additive, antagonistic or synergistic effects of alkaloids on chloroquine inhibition, respectively. Icajine and isoretuline were also assessed in vitro for their mefloquine potentiating activity on a mefloquine-resistant strain of Plasmodium falciparum. Only icajine proved to be synergistic with mefloquine (IF = 15.38). [less ▲]

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See detailMain Glucosidase Conversion Products of the Gluco-Alkaloids Dolichantoside and Palicoside
Brandt, V.; Tits, Monique ULg; Penelle, J. et al

in Phytochemistry (2001), 57(5), 653-9

The enzymatic glucose cleavage of palicoside revealed the biosynthetic pathway to akagerine, whereas the conversion of dolichantoside led to a new quaternary heteroyohimbine alkaloid named N(b)-methyl-21 ... [more ▼]

The enzymatic glucose cleavage of palicoside revealed the biosynthetic pathway to akagerine, whereas the conversion of dolichantoside led to a new quaternary heteroyohimbine alkaloid named N(b)-methyl-21-beta-hydroxy-mayumbine. The hypothetical models of reactions occurring after the conversion of both substrates are proposed. Dolichantoside and palicoside, as well as Strychnos mellodora stem bark crude ethanol extract, exhibit significant antimycotic activity against human pathogens in presence of specific glucosidase. [less ▲]

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See detailStrychnogucines a and B, Two New Antiplasmodial Bisindole Alkaloids from Strychnos Icaja
Frederich, Michel ULg; Gillet, Marie-Claire ULg; Prosperi, Christelle ULg et al

in Journal of Natural Products (2001), 64(1), 12-16

A reinvestigation of Strychnos icaja roots has resulted in the isolation of two tertiary quasi-symmetric bisindole alkaloids named strychnogucines A (1) and B (2). Their structures were identified by ... [more ▼]

A reinvestigation of Strychnos icaja roots has resulted in the isolation of two tertiary quasi-symmetric bisindole alkaloids named strychnogucines A (1) and B (2). Their structures were identified by means of spectroscopic data interpretation. Compound 2 was highly active in vitro and compound 1 moderately active against four strains of Plasmodium falciparum. Strychnogucine B (2) was more active against a chloroquine-resistant strain than against a chloroquine-sensitive one (best CI(50), 80 nM against the W2 strain). In addition, this compound showed a selective antiplasmodial activity with 25-180 times greater toxicity toward P. falciparum, relative to cultured human cancer cells (KB) or human fibroblasts (WI38). [less ▲]

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See detailCriterii de differentiere a unor specii de Veronica
Crisan, Gianina; Tamas, M.; Garbacki, Nancy ULg et al

in Farmacia (2001), 49(6), 67-73

We have tried to establish some criteria to avoid the substitution of Veronica officinalis L; with anti-ulcer and anti-inflammatory activities with other species of the genus Veronica, especially Veronica ... [more ▼]

We have tried to establish some criteria to avoid the substitution of Veronica officinalis L; with anti-ulcer and anti-inflammatory activities with other species of the genus Veronica, especially Veronica chamaedrys L. widely spread and without therapeutic use. We have studied the different histological, anatomical and phytochemical characters for the two species. A rapid method for the identification of both species is the TLC for flavonoids and phenylpropanic compounds was described. Moreover HPLC is useful to detect the presence of acteoside only in Veronica chamaedrys, while Veronica officinalis contains isoacteoside. [less ▲]

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See detailAnti-inflammatory effects of Centaurea cyanus (Asteraceae) flower-heads.
Garbacki, Nancy ULg; Gloaguen, Vincent; Damas, Jacques ULg et al

Poster (2001)

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See detailStrychnogucines A and B, two new antiplasmodial bisindole alkaloids from Strychnos icaja
Frederich, Michel ULg; Tits, Monique ULg; Penelle, Jacques et al

Poster (2000, September)

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