Catherine Vonthron-Sénécheau

• PhD
• Professor (Assistant) at University of Strasbourg

In a preliminary antiprotozoal screening of several Clusiaceae species, the methanolic extracts of Allanblackia monticola and Symphonia globulifera showed high in vitro leishmanicidal activity. Further bioguided phytochemical investigation led to the isolation of four benzophenones: guttiferone A (1), garcinol (2), cambogin (3) and guttiferone F (4...

Two anthraquinones, zenkequinones A and B were isolated from the stem bark of Stereospermum zenkeri together with known sterequinone-F, p-coumaric acid, sitosterol-3-O-beta-D-glucopyranoside and 3beta-hydroxyolean-12-en-28-O-beta-D-glucopyranoside. Their structures were established by spectroscopic methods. The antimicrobial activity of the isolate...

Eight extracts from four Ivorian medicinal plants, traditionally used to treat malaria, were tested for their antiplasmodial activity in vitro by assessing their ability to inhibit the uptake of [3H]hypoxanthine into the Plasmodium falciparum K1 chloroquine-resistant strain. The most active extract was the methylene chloride extract of Anogeissus l...

Eight extracts from seven selected Cameroonian medicinal plants, traditionally used to treat malaria and other protozoal diseases, were tested in vitro for their antiprotozoal activities against Plasmodium falciparum K1 chloroquine-resistant strain, Leishmania donovani, Trypanosoma cruzi and Trypanosoma brucei rhodesiense, protozoa responsible for...

The antiplasmodial, leishmanicidal and antitrypanosomal activities of eight natural biflavonoids were estimated in vitro on a chloroquine-resistant strain of Plasmodium falciparum, axenically grown Leishmania donovani amastigotes and Trypanosoma cruzi trypomastigotes and Trypanosoma brucei rhodesiense bloodstream forms. Lanaroflavone showed the hig...

Malaria remains a significant public health challenge in Niger, accounting for 5.6% of global malaria‐related deaths. Local medicinal plants are frequently used as traditional treatments for malaria, although their efficacy and safety are often insufficiently investigated. This study aims to evaluate the antiplasmodial activity and chemical composi...

In plants, the plastidial mevalonate (MVA)-independent pathway is required for the modification with geranylgeranyl groups of CaaL-motif proteins, which are substrates of protein geranylgeranyltransferase type-I (PGGT-I). As a consequence, fosmidomycin, a specific inhibitor of 1-deoxy-d-xylulose (DX)-5 phosphate reductoisomerase/DXR, the second enz...

The modification of GFP-CaaL sensor proteins by geranylgeranyl groups in plants requires an active plastidial mevalonate (MVA)-independent pathway. As a consequence, fosmidomycin, a specific inhibitor of 1-deoxy-D-xylulose (DX)-5 phosphate reductoisomerase/DXR, the second enzyme in this so-called methylerythritol phosphate (MEP) pathway, impedes pr...

Ethnopharmacological relevance Leishmaniasis are widely distributed among tropical and subtropical countries, and remains a crucial health issue in Amazonia. Indigenous groups across Amazonia have developed abundant knowledge about medicinal plants related to this pathology. Aim of the study We intent to explore the weight of different pharmacolog...

Vismione H (VH) is a fluorescent prenylated anthranoid produced by plants from the Hypericaceae family, with antiprotozoal activities against malaria and leishmaniosis. Little is known about its biosynthesis and metabolism in plants or its mode of action against parasites. When VH is isolated from Psorospermum glaberrimum, it is rapidly converted i...

Vismione H (VH) is a fluorescent prenylated anthranoid produced by plants from the Hypericaceae family, with antiprotozoal activities against malaria and leishmaniosis. Little is known about its biosynthesis and metabolism in plants or its mode of action against parasites. When VH is isolated from Psorospermum glaberrimum, it is rapidly converted i...

Ethnopharmacological relevance: Leishmaniasis are widely distributed among tropical and subtropical countries, and remains a crucial health issue in Amazonia. Indigenous groups across Amazonia have developed abundant knowledge about medicinal plants related to this pathology. Aim of the study: We intent to explore the weight of different pharmacol...

We present a development of the Plasmodesma dereplication method [Margueritte et al., Magn. Reson. Chem., 2018 56, 469]. This method is based on the automatic acquisition of a standard set of NMR experiments from a medium size set of samples differing by their bioactivity. From this raw data, an analysis pipeline is run and the data is analysed by...

This chapter focuses on the ability of flavonoid aglycones and glycosides to inhibit the growth of protozoan parasites of the genera Leishmania and Trypanosoma in different in vitro and in vivo models, namely pathogenic species for humans implicated in visceral (L. donovani, L. infantum) and cutaneous leishmaniasis (L. braziliensis, L. major, L. en...

Introduction Adansonia digitata leaves are used for the traditional treatment of hypertension in Senegal. This study evaluated the relaxant effect of a hydroethanolic extract of leaves of Adansonia digitata (ADF) in artery rings, and investigated the underlying mechanism. Methods Vascular reactivity was assessed in organ chambers. Rings were eithe...

Liquid state nuclear magnetic resonance (NMR) is a powerful tool for the analysis of complex mixtures of unknown molecules. This capacity has been used in many analytical approaches: metabolomics, identification of active compounds in natural extracts, and characterization of species, and such studies require the acquisition of many diverse NMR mea...

Liquid state NMR is a powerful tool for the analysis of complex mixtures of unknown molecules. This capacity has been used in many analytical approaches: metabolomics, identification of active compounds in natural extracts, characterization of species, and such studies require the acquisition of many diverse NMR measurements on series of samples. W...

Marine biodiversity contains resources composed of a variety of biologically active compounds. Marine macrophytes produce an array of secondary compounds still underexploited for their biomedical potential although they are a particularly available biomass. Studies of tropical marine macrophytes have shown their extensive biological activity, but v...

Background Acacia ataxacantha (Fabaceae), used in traditional medicine grows in the South-West of Bénin. Ethyl acetate extract of the barks of this species was previously reported to display various bioactivities, including antibacterial, antifungal and antioxidant activities. In the present study, we investigate the antimicrobial and antioxidant a...

Background Acacia ataxacantha is a medicinal specie used extensively in traditional medicine of Benin republic to treat infectious diseases. Our previous study showed interesting antibacterial and antifungal activities against six strains of bacteria and six strains of fungi. The aim of this study was to investigate the antimicrobial and antioxidan...

Phytochemical investigation of the methanol extract of Cyphostemma adenocaule liana (bark and wood) led to the isolation of two new ceanothane-type triterpenoids, cyphostemmic acid A 1 and cyphostemmic acid B 2, together with the known triterpenoids 3-7, β-sitosterol and its glucoside. The structures of the isolated compounds were established by 1D...

P. falciparum malaria is the deadliest parasitic disease with 438.000 deaths every year [1]. The increasing resistance of Plasmodium to antimalarials, notably to the first line treatment, artemisinins [2], is a major threat and fast acting drugs with new mechanisms of action are needed. We isolated an active biflavonoid from Campnosperma panamense...

A new method combining 2D-NMR techniques and bioactivity assay was developed with the aim of accelerating the discovery process of new bioactive natural products. Based on differential analysis of 2D-NMR spectra (DANS), the method allows identifying molecular fingerprints related to biological activity (pharmacophoric fingerprint) within a complex...

Ethnopharmacological relevance: Psidium acutangulum Mart. ex DC is a small tree used by the Wayana Amerindians from the Upper-Maroni in French Guiana for the treatment of malaria. Aim of the study: In a previous study, we highlighted the in vitro antiplasmodial, antioxidant and anti-inflammatory potential of the traditional decoction of P. acuta...

Phytochemical investigation of the leaves of Phragmanthera capitata collected on Cassia spectabilis tree led to the isolation of two natural lactones, rel-(1R,5S,7S)-7-[2-(4-hydroxyphenyl)ethyl]-2,6-dioxabicyclo[3.3.1]nonan-3-one (1) and 4-{2-[rel-(1R,3R,5S)-7-oxo-2,6-dioxabicyclo[3.3.1]non-3-yl]ethyl}phenyl 3,4,5-trihydroxybenzoate (2) together wi...

Background Ever since 2008 when evidence of artemisinin resistant malaria has been highlightened in Western Cambodia [1] the need for new drugs with an original structure and novel mechanisms of action is even more pressing. By the past, the study of traditional remedies such as Cinchona bark or Artemisia aerial parts led to the discovery of the mo...

Psidium acutangulum Mart. ex DC is used exclusively by the Wayana Amerindians in French Guiana, more particularly for the treatment of malaria. To understand this specific use, we embarked upon evaluating the antimalarial and anti-inflammatory activities of this traditional remedy as prepared by the Amerindian users. The decoction exerted good anti...

Organic extracts of 20 species of French seaweed have been screened against Trypanosoma brucei rhodesiense trypomastigotes, the parasite responsible for sleeping sickness. These extracts have previously shown potent antiprotozoal activities in vitro against Plasmodium falciparum and Leishmania donovani. The selectivity of the extracts was also eval...

A total of fourteen extracts with different polarity obtained from four species Crataeva religiosa, Baillonella toxisperma, Boswellia dalzielii and Khaya senegalensis, traditionally used in Benin to treat malaria were tested for their in vitro antiprotozoal activity towards Plasmodium falciparum, Trypanosoma rhodesiense, Trypanosoma cruzi and Leish...

Schrankia leptocarpa is a medicinal species use traditionally in Benin to treat malaria. A previous study showed interesting antimalarial activity against two strains of Plasmodium falciparum. Phytochemical investigation of S. leptocarpa DC. (Mimosaceae) led to the isolation of two diarylheptanoids (1–2), three phenolic acid (3–5), one p-coumaric a...

The title octa­deca­trienoic acid derivative, C18H26O4, was isolated from Silene maritima With. (Caryophyllaceae), the first time this natural compound has been found in the Caryophyllales order. This fatty acid has an 18-carbon backbone with three double bonds on trans (E) conformation and two carbonyl. In the crystal, molecules are linked via pai...

Eleganolone has been isolated by a bioassay-guided approach from a crude ethyl acetate extract of Bifurcaria bifurcata, as a putative active principle responsible of the strong trypanocidal activity previously found in this extract. The in vitro activity of eleganolone against Trypanosoma brucei rhodesiense and Trypanosoma cruzi trypomastigotes wil...

Parinari excelsa Sabine (Chrysobalanaceae) is an indigenous tree from West and Eastern Africa. This tree is used in Ivory Coast as an antimalaria remedy. The in vitro antiplasmodial and antileishmanial activities of the stem bark, the leaf and the major compounds from the stem bark were investigated. The leaves and stem bark from P. excelsa were se...

Anogeissus leiocarpus Guill. & Perr. (Combretaceae) is an African indigenous tree. It has been of interest to researchers because it is used in Ivory Coast as antimalaria remedy. The in vitro antiplasmodial and antileishmanial activities of the leaf and it major constituents are investigated her for the first time. Chemical composition of ethyl ace...

Marine macrophytes contain a variety of biologically active compounds, some reported to have antiprotozoal activity in vitro. As a part of a screening program to search for new natural antiprotozoals, we screened hydroalcoholic and ethyl acetate extracts of 20 species of seaweeds from three phyla (Rhodophyta, Heterokontophyta and Chlorophyta), samp...

Modern drug discovery is greatly based on the identification and structural characterization of new lead compounds, stemming from the huge diversity of natural plant chemicals. The process is tedious facing the complexity of plant metabolome, and the time-consuming steps of purification. In order to reduce the number of de novo purification and elu...

Phytochemical investigation of the bark and leaves of Pancovia laurentii (Sapindaceae) resulted in the isolation of a new ceramide and a new cerebroside, named pancoviamide (1), and pancovioside (2) respectively, together with six known compounds: uracil, (R)-N-[(1S,2S,3R)-2,3-dihydroxy-1-(hydroxymethyl)heptadec-5-en-1-yl]-2-hydroxytetracosanamide,...

Marine macrophytes have been highlighted as resources containing a variety of biologically active compounds and particularly showing in vitro antiprotozoal activities1,2. As a part of a screening program to search new natural antiprotozoal products, we screened 20 seaweed species from the Normandy's coast belonging to Rhodophyta, Pheophyta and Chlo...

Phytochemical investigation of an ethyl-acetate extract of the stem bark of Markhamia tomentosa (Bignoniaceae), which had good antimalarial activity in vitro, resulted in the isolation of eight known compounds: 2-acetylnaphtho[2,3-b]furan-4,9-dione (1), 2-acetyl-6-methoxynaphtho[2,3-b]furan-4,9-dione (2), oleanolic acid (3), pomolic acid (4), 3-ace...

Two new acylated flavonol pentaglycosides were isolated from the butanolic extract of Baphia nitida leaves by Sephadex LH-20 and preparative HPLC. Structural elucidation of kaempferol 3-O-β-d-xylopyranosyl(1→3)-(4-O-E-p-coumaroyl-α-l-rhamnopyranosyl(1→2))[β-d-glucopyranosyl(1→6)]-β-d-galactopyranoside-7-O-α-l-rhamnopyranoside (1) and kaempferol 3-O...

In a preliminary evaluation of ethnobotanically selected Beninese medicinal plants for their in vitro antiplasmodial activity, the methanolic extract of the aerial parts of C. lobatus was found to have significant activity against P. falciparum, antileishmainal and antiprotoazoal assays carried out on some of the isolated compounds. Phytochemical i...

Thalia geniculata. L. (Marantaceae) is an African medicinal plant traditionally used in Benin to treat malaria and other parasitic diseases. There is little ethnobotanical and almost no chemical information available for this species. The phytochemical analysis of the aerial parts of the plant led to the isolation of five compounds, identified as s...

The natural floridoside (2-O-alpha-d-galactopyranosylglycerol) was isolated from Dilsea carnosa, and its structure has been determined by single-crystal X-ray diffraction analysis. The solved structure is in agreement with the previously solved crystal structure of floridoside [Simon-Colin, C.; Michaud, F.; Léger, J.-M.; Deslandes E. Carbohydr. Res...

Lanaroflavone (1), a biflavonoid isolated from the methanol extract of the aerial part of Campnosperma panamense by bioguided fractionation, has been assessed for in vitro antiprotozoal activity. Lanaroflavone showed both antimalarial and leishmanicidal activities, but was inactive against Chagas disease vector, Trypanosoma cruzi.

Twenty extracts from nine Benin medicinal plants, traditionally used to treat malaria, were screened for in vitro antiplasmodial activity towards Plasmodium falciparum K1 chloroquine resistant and 3D7 chloroquine sensitive strains. All plants showed antiplasmodial activity below 10 μg/ml. Nine extracts exhibited IC50 values below 5 μg/ml towards on...

I1 imidazoline receptors (I1R) were defined as receptors insensitive to catecholamines and highly sensitive to [3H]clonidine and analogs. By contrast, the I2R subtype is more sensitive to [3H]idazoxan. [3H]clonidine and [3H]idazoxan imidazoline specific binding sites (IBS) have been detected in crude human membranes. Pharmacologic characterization...

I, imidazoline receptors (I1R) were defined as receptors insensitive to catecholamines and highly sensitive to [H-3]clonidine and analogs. By contrast, the I2R subtype is more sensitive to [H-3]idazoxan. [H-3]clonidine and [H-3]idazoxan imidazoline specific binding sites (IBS) have been detected in crude human membranes. Pharmacologic characterizat...

Nonadrenergic imidazoline-specific binding sites were characterized pharmacologically in crude cerebral membrane preparations, but little is known about their subcellular localization in neurons. As in the brainstem these sites are involved in cardiovascular regulation and peripherally imidazolines modulate neurotransmitter release, we tried to det...

The site of the hypotensive action of imidazoline compounds, such as clonidine, was first identified within the rostroventrolateral part of the brainstem: the nucleus reticularis lateralis. After that, it was shown that imidazolines and related substances reduced blood pressure when applied in this area whereas catecholamines were not capable of pr...

Imidazoline receptors (I-receptors) are considered as potential therapeutic targets for a spectrum of stress-induced illnesses. Yet, I-receptors remain poorly defined at the molecular level. In this study, candidate imidazoline receptor proteins were compared using two imidazoline receptor-selective antisera of diverse origins. One antiserum was de...

Biochemical characteristics of imidazoline specific binding sites from the human brainstem were further investigated using [3H]idazoxan as radiolabeled ligand. The study of the interaction of [3H]idazoxan binding sites with heparin and lectins (soybean and lentil lectin) confirm the heterogeneity of these sites in the human brain. In fact, about 10...

Polyclonal antibodies were raised in rabbits against purified polyclonal anti-idazoxan antibodies. The anti-idiotypic antibodies thus obtained, proved able to inhibit [3H]idazoxan specific binding to anti-idazoxan antibodies. Applied to human nucleus reticularis lateralis membrane preparations, these antibodies (20 micrograms) inhibited about 50 an...