References of "Angenot, Luc"
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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 detailSupercritical carbon dioxide extraction of tagitinin C from Tithonia diversifolia
Ziemons, Eric ULg; Goffin, Eric ULg; Lejeune, Robert ULg et al

in Journal of Supercritical Fluids (2005), 33(1), 53-59

Different parameters as temperature, pressure, solvent mass and sample granulometry governing the extraction yield of tagitinin C from the aerial parts of Tithonia diversifolia were optimised. An ... [more ▼]

Different parameters as temperature, pressure, solvent mass and sample granulometry governing the extraction yield of tagitinin C from the aerial parts of Tithonia diversifolia were optimised. An experimental design was carried out to map the effects of pressure (at 20.3, 30.4 and 40.5 MPa) and temperature (at 40, 60 and 80degreesC) on the extraction yield of the active component and to determine the optimal conditions for the extraction of tagitinin C from T diversifolia. The best conditions are met for a pressure of 35.0 MPa and a temperature of 68degreesC. The effect of the particle size was studied under low pressure (13.7 MPa) and temperature (40degreesC) conditions, which failed to extract quantitatively the tagitinin C from leaves sieved to 250 mum size. The reduction of the particle size increased the extraction yield which became comparable to that of the optimised SFE for the particle in the range of 0-63 mum. From the analysis of extraction kinetic curves of 200 mg of plant with supercritical carbon dioxide (range of 5-30 g), it appears that 15 g of this supercritical fluid is never limiting. The optimised supercritical fluid extraction (SFE) was compared favourably to Soxhlet extraction with dichloromethane (S) and to maceration followed by lixiviation with diethyl ether (ML), which gave similar extraction yields but higher extract content of tagitinin C were found using SFE (15.6 and 30.7% w/w tagitinin C in S and ML extracts, respectively, versus 52.8% in SFE extract). [less ▲]

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See detailAcute liver failure with renal impairment related to the abuse of senna anthraquinone glycosides
Vanderperren, Bénédicte; Rizzo, Michela; Angenot, Luc ULg et al

in Annals of Pharmacotherapy (2005), 39(7-8, JUL-AUG), 1353-1357

OBJECTIVE: To report a case of chronic ingestion of very large amounts of senna fruits as an herbal tea, possibly leading to severe hepatotoxicity. CASE SUMMARY: A 52-year-old woman who had ingested, for ... [more ▼]

OBJECTIVE: To report a case of chronic ingestion of very large amounts of senna fruits as an herbal tea, possibly leading to severe hepatotoxicity. CASE SUMMARY: A 52-year-old woman who had ingested, for > 3 years, one liter of an herbal tea each day made from a bag containing 70 g of dry senna fruits, developed acute hepatic failure and renal impairment requiring intensive care therapy. The severity of the hepatic failure was reflected by the increase in prothrombin time (international normalized ratio > 7) and the development of encephalopathy. Liver transplantation was discussed, but the patient ultimately recovered with supportive therapy. Renal impairment was consistent with proximal tubular acidosis, also with marked polyuria refractory to vasopressin administration. Suprisingly, large amounts of cadmium were transiently recovered in the urine. DISCUSSION: Cassia acutifolia and angustifolia plants are widely used as laxatives. Their chronic abuse may be associated with serious manifestations, including fluid and electrolyte loss, with chronic diarrhea. Severe hepatotoxicity is unusual, but could be explained by the exposure of the liver to unusual amounts of toxic metabolites of anthraquinone glycosides (sennosides). An objective causality assessment suggests that hepatotoxicity was possibly related to senna laxative abuse. Regarding nephrotoxicity, there are no available human data on sennosides, while experimental models suggest that anthraquinone derivatives may also accumulate in the kidneys. The finding of high urinary concentrations of cadmium would suggest contamination of the herbal tea by metals, but this hypothesis could not be verified. CONCLUSIONS: Ingestion of large doses of senna laxatives may expose people to the risk of hepatotoxicity. [less ▲]

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See detailFolipidine, a new type quinoline alkaloid from plants of the Haplophyllum genus
Akhmedzhanova, V. I.; Rasulova, K. A.; Bessonova, I. A. et al

in Chemistry of Natural Compounds (2005), 41(1, JAN-FEB), 60-64

The new quinoline alkaloid folipidine, the structure of which was established by chemical transformations and spectral data (UV, IR, mass, NMR) using APT 2D H-1-H-1 COSY, NOESY, and H-1-(13)CHSQC, HMBC ... [more ▼]

The new quinoline alkaloid folipidine, the structure of which was established by chemical transformations and spectral data (UV, IR, mass, NMR) using APT 2D H-1-H-1 COSY, NOESY, and H-1-(13)CHSQC, HMBC, was isolated from two plants of the Haplophyllum mints. Folipidine is the first representative of a new type of quinoline alkaloids that contain a heteroaromatic skeleton of [3,4-b]conjugated pyrrole and quinoline fragments. The total alkaloids of these plants exhibit antitumor activity. Folipidine does not possess such activity. [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 detailMetabolomic analysis of Strychnos nux-vomica, Strychnos icaja and Strychnos ignatii extracts by H-1 nuclear magnetic resonance spectrometry and multivariate analysis techniques
Frederich, Michel ULg; Choi, Young Hae; Angenot, Luc ULg et al

in Phytochemistry (2004), 65(13), 1993-2001

H-1 Nuclear magnetic resonance spectrometry and multivariate analysis techniques were applied for the metabolic profiling of three Strychnos species: Strychnos nux-vomica (seeds, stem bark, root bark ... [more ▼]

H-1 Nuclear magnetic resonance spectrometry and multivariate analysis techniques were applied for the metabolic profiling of three Strychnos species: Strychnos nux-vomica (seeds, stem bark, root bark), Strychnos ignatii (seeds), and Strychnos icaja (leaves, stem bark, root bark, collar bark). The principal component analysis (PCA) of the H-1 NMR spectra showed a clear discrimination between all samples, using the three first components. The key compounds responsible for the discrimination were brucine, loganin, fatty acids.. and Strychnos icaja alkaloids such as icajine and sungucine. The method was then applied to the classification of several "false angostura" samples. These samples were, as expected, identified as S. nux-vomica by PCA, but could not be clearly discriminated as root bark or stem bark samples after further statistical analysis. (C) 2004 Published by Elsevier Ltd. [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 detailFT-IR measurement of tagitinin C after solvent extraction from Tithonia diversifolia
Ziemons, Eric ULg; Goffin, Eric ULg; Lejeune, Robert ULg et al

in Talanta (2004), 62(2), 383-387

Tagitinin C, an antiplasmodial compound, identified as one major compound of the subtropical medicinal plant, Tithonia diversifolia, was, determined by FT-IR spectroscopy method. The crude ether extracts ... [more ▼]

Tagitinin C, an antiplasmodial compound, identified as one major compound of the subtropical medicinal plant, Tithonia diversifolia, was, determined by FT-IR spectroscopy method. The crude ether extracts from aerial parts of the plant were evaporated to dryness and re-dissolved in tetrachloroethylene (C2Cl4) before analysis. The magnitude of the absorbance of the very specific C=O stretching vibration (v(c=o)) at 1664.8 cm(-1) was exploited in order to quantify tagitinin C. The determination coefficient (r(2)) of the calibration scale was 0.9994, the detection limit was lower than 3 mug ml(-1) and the quantification limit was lower than 10 mug ml(-1). Recovery values from 100.5 to 101.7% were found for spiked concentration levels from 19.91 to 89.95 mug ml(-1). The main characteristics of the curves obtained from the calibration standards and from the standard addition technique were not statistically different (Student t-test) suggesting that matrix effects were negligible. The results obtained for the determination of tagitinin C in the crude ether extract from aerial parts of T diversifolia by LC and FT-IR spectroscopic method agreed well: 0.76 +/- 0.02 and 0.773 +/- 0.009, of tagifinin C in dried plant respectively. (C) 2003 Elsevier B.V. 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 (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 (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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See detailIsostrychnopentamine, an indolomonoterpenic alkaloid from Strychnos usambarensis, induces cell cycle arrest and apoptosis in human colon cancer cells
Frederich, Michel ULg; Bentires-Alj, M.; Tits, Monique ULg et al

in Journal of Pharmacology and Experimental Therapeutics (2003), 304(3), 1103-1110

Isostrychnopentamine (ISP) is an indolomonoterpenic alkaloid that is present in the leaves of Strychnos usambarensis, a well known African shrub or little tree. The roots contain quaternary alkaloids ... [more ▼]

Isostrychnopentamine (ISP) is an indolomonoterpenic alkaloid that is present in the leaves of Strychnos usambarensis, a well known African shrub or little tree. The roots contain quaternary alkaloids, which are used to make a curare-like arrow poison. However, tertiary alkaloids isolated from the same plant possess cytotoxic activities against mammalian cells and protozoa. The effect of ISP has been investigated on the growth and viability of HCT-116 colon cancer cells during their exponentially growing phase. ISP induced apoptotic cell death as shown by the translocation of phosphatidylserine from the inner layer to the outer layer of the plasma membrane, chromatin condensation, DNA fragmentation, and caspase-3 and -9 activation. ISP provoked also cell cycle arrest in the G(2)-M phase. We also showed that the expression of p53 was not modified in ISP-treated cells, but that p21 was induced in a p53-independent manner. Finally, we demonstrated that ISP did not affect the catalytic activity of human topoisomerases I and II. In conclusion, ISP, which promotes cell death by a p53-independent apoptotic pathway, could be an interesting lead for cancer chemotherapy. [less ▲]

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See detailApoptosis induction in human cancer cells by sungucine from Strychnos icaja root
Frederich, Michel ULg; Bentires-Ali, M.; Tits, Monique ULg et al

in Naunyn-Schmiedeberg's Archives of Pharmacology (2003), 367(3), 260-265

Sungucine (SG) and isosungucine (ISG) are bisindole alkaloids characterized by a 5'-23 link between the two parts of the compounds, which are till now specific to Strychnos icaja. In this work, SG and ISG ... [more ▼]

Sungucine (SG) and isosungucine (ISG) are bisindole alkaloids characterized by a 5'-23 link between the two parts of the compounds, which are till now specific to Strychnos icaja. In this work, SG and ISG were submitted to the NCI's in vitro 60 human tumor cell line screen, where SG showed interesting selectivity (6X) against the tested leukemia cell lines. In HL60-treated cells, apoptosis was demonstrated by observation of apoptotic bodies formation, and phosphatidylserine exposition at cell surface. In HeLa-treated cells, the analysis of cellular cycle by flow cytometry showed G1 accumulation and a small sub-G1 peak that could be related to DNA fragmentation characteristic of apoptosis. The eventual role of p53 was analyzed using wild-type HCT-116 colon cancer cells. Nevertheless, p53 and Bax expression were not modified in SG-treated cells. The cleavage of PARP by caspase-3 protease proved that apoptosis was also induced in this line. These results demonstrate that SG induces apoptosis, but also necrosis, in human cancer cell lines. [less ▲]

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See detailIndolomonoterpenic alkaloids from Strychnos icaja roots
Philippe, Geneviève ULg; De Mol, Patrick ULg; Zeches-Hanrot, M. et al

in Phytochemistry (2003), 62(4), 623-629

In the course of our search for new antiplasmodial alkaloids from Strychnos icaja, we have isolated five alkaloids: three monomers, protostrychnine and genostrychnine, previously described in Strychnos ... [more ▼]

In the course of our search for new antiplasmodial alkaloids from Strychnos icaja, we have isolated five alkaloids: three monomers, protostrychnine and genostrychnine, previously described in Strychnos nux-vomica, pseudostrychnine, already found in the leaves of the plant, a new bisindolic alkaloid, named strychnogucine C, and the first naturally occurring trimeric indolomonoterpenic alkaloid: strychnohexamine. This latter trimeric alkaloid presented an antiplasmodial activity against the FCA Plasmodium falciparum line near I muM. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailBisindole alkaloids from Strychnos guianensis are effective antagonists of nicotinic acetylcholine receptors in cultured human TE671 cells
Wins, Pierre; Margineanu, Ilca; Penelle, Jacques et al

in Naunyn-Schmiedeberg's Archives of Pharmacology (2003), 367(3), 253-259

Several mono- and bisindole quaternary alkaloids isolated from the stem bark of Strychnos guianensis have recently been shown to be effective blockers of neuromuscular transmission in mice. In this study ... [more ▼]

Several mono- and bisindole quaternary alkaloids isolated from the stem bark of Strychnos guianensis have recently been shown to be effective blockers of neuromuscular transmission in mice. In this study, we used a human clonal cell line (TE671) expressing muscle-type nicotinic acetylcholine receptors. The agonist carbamylcholine activated a receptor-mediated Rb-86(+) efflux and this activation was antagonized by the indole alkaloids, the most active being bisindole bisquaternary compounds. The most effective antagonist, guiachrysine, had an IC50 around 0.43 muM in the presence of 0.5 mM carbamylcholine, compared to 0.16 muM for d-tubocurarine, the most potent curarizing alkaloid. Guiaflavine and 5',6'-dehydroguiaflavine were slightly less effective. Monoindole compounds were 10 to 100 times less potent than bisindole alkaloids. Kinetic analysis showed that the inhibition of the carbamylcholine-dependent Rb-86(+) efflux by guiaflavine was of mixed competitive and uncompetitive type. The competitive component (K-I = 0.21 muM) is presumably due to binding at the acetylcholine site, while the uncompetitive component (K'(I) = 0.92 muM) may be due to open channel block. [less ▲]

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