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International audience; Ten tocotrienol derivatives, i.e., amplexichromanols (1–10), were isolated from stem bark of Garcinia amplexicaulis Vieill. ex Pierre collected in Caledonia. The structures of the compounds 1–5 were determined to be chromanol derivatives substituted by a polyprenyl chain oxidized in terminal position. The remaining compounds 6–10 are the corresponding dimeric derivatives. Eleven known compounds, including xanthones, tocotrienol derivatives, triterpenes and phenolic compounds, were also isolated. Their structures were mainly determined using one and two-dimensional NMR and mass spectroscopy analysis. The compounds and some amplexichromanol molecules formerly isolated from G. amplexicaulis exhibited significant antioxidant activity against lipid peroxidation and in the ORAC assay.

International audience

Polyphenols have favorable antioxidant potential on human health suggesting that their high content is responsible for the beneficial effects of apple consumption. They control the quality of ciders as they predominantly account for astringency, bitterness, color and aroma. In this study, we identified QTLs controlling phenolic compound concentrations and the average polymerization degree of flavanols in a cider apple progeny. Thirty-two compounds belonging to five groups of phenolic compounds were identified and quantified by reversed phase liquid chromatography on both fruit extract and juice, over three years. The average polymerization degree of flavanols was estimated in fruit by phloroglucinolysis coupled to HPLC. Parental maps were built using SSR and SNP markers and used for the QTL analysis. Sixty-nine and 72 QTLs were detected on 14 and 11 linkage groups of the female and male maps, respectively. A majority of the QTLs identified in this study are specific to this population, while others are consistent with previous studies. This study presents for the first time in apple, QTLs for the mean polymerization degree of procyanidins, for which the mechanisms involved remains unknown to this day. Identification of candidate genes underlying major QTLs was then performed in silico and permitted the identification of 18 enzymes of the polyphenol pathway and six transcription factors involved in the apple anthocyanin regulation. New markers were designed from sequences of the most interesting candidate genes in order to confirm their co-localization with underlying QTLs by genetic mapping. Finally, the potential use of these QTLs in breeding programs is discussed.

International audience; Accumulation in tissues and serum of advanced glycation end-products (AGEs) plays an important role in pathologies such as Alzheimer’s disease or, in the event of complications of diabetes, atherosclerosis or renal failure. Therefore, there is a potential therapeutic interest in compounds able to lower intra and extracellular levels of AGEs. Among them, natural antioxidants (AO) with true anti-AGEs capabilities would represent good candidates for development. The purpose of this study was to evaluate the AO and anti-AGEs potential of a propolis batch and then to identify the main compounds responsible for these effects. In vivo, protein glycation and oxidative stress are closely related. Thus, AO and antiglycation activities were evaluated using both DPPH and ORAC assays, respectively, as well as a newly developed automated anti-AGEs test. Several propolis extracts exhibited very good AO and anti-AGEs activities, and a bioguided fractionation allowed us to identify pinobanksin-3-acetate as the most active component.

Voltage-gated sodium channels (Nav) constitute the molecular targets of clinically used drugs for treatments of various diseases (epilepsies, chronic pain, cardiac arrythmies…) and also of numerous toxins from animals and plants. The development of useful screening assay for the discovery of new ligands in/ from chemicals libraries or animal venoms and either plant extract still represents a challenge of great interest. Here, we used a mammalian GH3 cells that constitutively express at least three different brain Nav channels isoforms (Nav1.1, Nav1.2, Nav1.3 and Nav1.6) in order to identify in a library of in-house natural alkaloids, novel compounds of therapeutical interest. For this screening, we developed a method based on the use of Voltage Sensor Probes (VSPs) that we adapted to detect both activators and blockers of Nav channels. Among 62 compounds tested, 5 isoquinolines appeared as potent Nav channels inhibitors. Other compounds were characterized as specific gating modifier of Nav channels. While most of these alkaloids have been already described in the literature, their abilities to act on Nav channels were unknown. In conclusion, we demonstrated the potency of this novel screening method using VSPs to identify novel ligands of Nav channels of therapeutical interests.References:1. Salat, K. et al. (2014) EOID 23:1093-11042. Yu, F.H. et al (2003) Genome Biol. 4

Oxidative stress and advanced glycation end products (AGEs) are known as key factors for the development of diabetic complications such as retinopathy, cataract as well as atherosclerosis and neurodegenerative diseases, including Alzheimer’s diseases. In this context, natural products have been previously identified as promising sources for antioxidant and anti-glycation compounds. The current study focuses on the evaluation of antioxidant and glycation inhibitory activities of different solvent extracts of Solanum elaeagnifolium Cav (Solanaceae) fruits at different ripening stages. The results showed that antioxidant and anti-AGEs activities were significantly influenced by solvents polarities and ripening stages of S. elaeagnifolium Cav. With one exception, methanolic extract of overripe S. elaeagnifolium Cav fruit showed important protective effects against cellular oxidative stress. The aqueous extract showed the highest ABTS+ scavenging ability. Principal component analysis showed that total phenolic and flavonoid contents correlated well with observed antioxidants and anti-glycation activities. These results bring attention to the possible use of S. elaeagnifolium Cav as a valuable source of bioactive compounds exhibiting antioxidant effects and potentially alleviating diabetic complications., EXCLI Journal ; Vol. 13, 2014

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International audience; Therapeutic education provides a significant benefit in terms of quality of life and compliance in patients suffering from atopic dermatitis. The setting up of care networks could also play a major role in lowering the cost of treatments, as shown by the experience of Nantes University Hospital's atopy school.; L’éducation thérapeutique apporte un bénéfice significatif en termes de qualité de vie et d’observance chez les patients souffrant de dermatite atopique. La mise en place de réseaux de soins pourrait également jouer un rôle majeur sur la diminution des coûts de traitements, comme le montre l’expérience de l’école de l’atopie du Centre hospitalier universitaire de Nantes (44).

International audience; As widely used by patients as they are criticised by doctors, complementary therapies do not feature in any recommendations or consensus conferences due to the lack of strong evidence of their efficacy. However, some of these therapies can represent a credible alternative depending on the individuals. They can form part of patients’ personalised care, notably those suffering from atopic dermatitis.; Aussi largement utilisées par les patients que décriées par les médecins, les thérapeutiques complémentaires sont absentes des recommandations et des conférences de consensus en raison de l’extrême faiblesse de leur niveau de preuve. Pour autant, certaines représentent une alternative crédible en fonction des individus. Elles peuvent participer à la personnalisation du soin des patients, notamment ceux atteints de dermatite atopique.

The structural identification of natural products is one of the major focus areas of analytical chemistry research. Mass spectrometry (MS) has long been used to obtain molecular weights and further molecular formulae. In the past, former ionization sources such as electronic impact unfortunately limited MS analysis to predominately volatile, polar, and thermostable compounds. However, recent developments in soft ionization techniques such as electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI), or laser desorption/ionization (LDI) have gradually extended MS analysis to a much wide range of chemical structures. As far as small natural compounds are concerned, LDI sources are still seldom used because of specific technical limitations. Indeed, the photoionization process of LDI is generally assisted by a matrix, which is a small molecule carrying strong UV chromophore. The process is then called matrix-assisted laser desorption/ionization (MALDI) process. MALDI ionization therefore induces the formation of numerous matrix ions that commonly appear in the range 0–600 Da, and consequently interfere with molecular ions originating from many natural products. For this reason, the correct signal assignment is highly impaired in the critical region of interest. As LDI and MALDI are not only soft ionization processes but also quite sensitive techniques yielding high resolution spectra when coupled to a time-of-flight (TOF) analyzer, different attempts have been made to adapt these techniques for the analysis of natural products. Three of them will be more specifically discussed in this chapter: (i) LDI on neat gold surfaces obtained by physical vapor diffusion (PVD), (ii) desorption/ionization on self-assembled monolayer surfaces (DIAMS), and (iii) the use of specific matrices for the selective detection of alkaloids. Keywords: laser desorption ionization; mass spectrometry; secondary metabolites; MALDI; self-assembled monolayers

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International audience; Lichens are resilient organisms, known for their unique profiles of secondary metabolites and for exhibiting antioxidative, antibacterial, and cytotoxic effects. Analyzing the cytotoxic potential ofLobaria scrobiculata, a bioassay-guided fractionation strategy yielded seven known metabolites, with two of these compounds,2and3, exhibiting cytotoxicity against HL-60 cells. In order to verify the potential impact of degradation on observed bioactivity, a purity and stability evaluation was conducted. The consistency of results obtained by the water-soluble tetrazolium salt-1 assay and trypan blue cytotoxicity assay was evaluated for selected compounds.

National audience

International audience; Propolis, or bee glue, is a natural resinous hive product collected by honeybees from buds and exudates of various trees and plants. Mixed with beewax and salivary enzymes, it is used to fill in cracks and holes in the hive as well as a chemical weapon against intruders. It is well known that the chemical composition of propolis depends on the flora at the site of collection. The aim of this study was to compare two different propolis batches. The first one collected in France (south-west) and the second one in Quintana Roo, Mexico. The ethanolic extract of the French propolis (EEP) contained mainly polyphenols such as phenolic acids and their esters and flavonoids (poplar type), while the same kind of extract from the Mexican propolis showed only triterpenoids such as α and β-amyrin derivatives. Although the latter composition is quite unusual for a Mexican propolis, α and β-amyrins -and their derivatives- have been reported to occur in the resin of Bursera simaruba,1 a tree that grows in Quintana Roo. Both propolis were evaluated in terms of their biological activity, including antioxidant (DPPH), anti-AGEs, antifungal (Candida albicans and Aspergillus fumigatus), and antibacterial (21 Gram-positive and Gram-negative strains including Staphyloccocus aureus). Whereas French EEP exhibited high antioxidant and anti-AGEs activities,2 as well as very good antifungal (towards C. albicans) and antibacterial (towards S. aureus) activities, Mexican EEP proved to be inactive. These results suggest that the chemical composition of the propolis collected in Quintana Roo is qualitatively and quantitatively of particular importance in the ecological interaction between the bees and the parasites and microorganisms that occur specifically in that region.

International audience; Notopterygiumroots (Qiang Huo) have been used in traditional Chinese medicine for treating colds, inflammatory diseases like rheumatoid arthritis, and as an analgesic. The anti-inflammatory activity of the roots ofNotopterygium incisumhas been evaluated by testing the inhibitory activity on nitric oxide production by inducible nitric oxide synthase. The apparent authenticity of the sample was checked by DNA sequence comparison. Using activity-guided isolation, different compounds were isolated and structurally characterized by means of NMR and mass spectroscopy. Eight polyacetylenes could be identified and were tested on their inhibitory activity on nitric oxide production in RAW 264.7 mouse macrophages using the Griess assay. Different 3-hydroxy allyl polyacetylenes exhibited significant activity (IC50: 8-acetoxyfalcarinol, 20.1 µM; falcarindiol, 9.2 µM; 9-epoxyfalcarindiol, 8.8 µM; and crithmumdiol, 23.6 µM).

International audience; Aim: This study focused on finding molecules with inhibitory effects on Advanced Glycation End-products (AGEs) formation from Tanzanian some Clusiaceae plant speciesStudy Design: Field study and Laboratory experimental tests.Place and Duration of Study: Institute of Traditional Medicine, Muhimbili University of Health and Allied Sciences, P.O. Box 65001, Dar es Salaam, Tanzania and PRES LUNAM, Université d’Angers, EA 921 SONAS, 16 Bd Daviers, 49045 Angers, France, between June 2011 and July 2013.Methodology: Three Clusiaceae plant species (Garcinia semseii, G. volkensii and Allanblackia ulugurensis) were collected and dried in the field with the assistance of a botanist. Extraction and concentration of plant samples to obtain crude extracts were done in the laboratory following standard procedures. The isolation of the phenolic compounds was carried out by using normal phase column chromatography as well as High-performance liquid chromatography (HPLC). The isolated compounds were tested for anti-AGE activity using the in vitro automated assay.Results: Two polyphenolic compounds exhibiting phloroglucinol moieties [e.g. polyprenylated benzophenones, such as guttiferone F, 2 (18 mg)] or biflavonoids [such as morelloflavone, 1 (22mg)] were isolated and identified from A. ulugurensis and G. volkensis respectively. The results further indicated that compound 1 is an excellent inhibitor of AGE formation exhibiting an IC50 values of 78 and 64 µM at wavelength of 370/440 (vesperlysines-like AGEs) and 335/385 (pentosidine-like AGEs) respectively.Conclusion: Plants belonging to the Clusiaceae family commonly used in Tanzanian traditional medicine need to be considered as a potential source of molecules exhibiting pharmacological activities such as anti-AGE activity. Morelloflavone (1) and other biflavonoids prove to be very good anti-AGE compounds using our automated screening assay. Hence, our automated in vitro assay allows a fast, effective and quite inexpensive screening of natural compounds and can therefore be applied to high throughput screening projects.

International audience; Adapted phytotherapy solutions to fight sleep disorders. Many French people suffer from insomnia, a disorder which can lead to other conditions (related to mood, memory) as well as excessive use of medication and which can also increase morbidity and mortality. To fight against sleep disorders, numerous plant-based therapies are available, including in pharmacies where pharmacists must have in-depth knowledge of their composition and know how to assess their effectiveness to list the best.; De nombreux Français souffrent d’insomnie, trouble en entraînant d’autres (humeur, mémoire) ainsi qu’une consommation médicamenteuse excessive, et augmentant morbidité et mortalité. Pour lutter contre les troubles du sommeil, de nombreux produits de phytothérapie sont proposés, y compris dans les officines où les pharmaciens doivent maîtriser leur composition et savoir évaluer leur efficacité pour référencer les meilleurs.

International audience; Atopic dermatitis: some general remarks. Atopic dermatitis, also called atopic eczema, is a chronic inflammatory skin disease, usually observed in infants but which can also occur in adults and elderly people. Increasingly prevalent, atopic dermatitis today constitutes a public health issue, notably as a result of the influence of the environment on the genotype.; La dermatite atopique, également appelée eczéma atopique, est une dermatose inflammatoire chronique, s’observant le plus souvent chez le nourrisson, mais pouvant aussi apparaître à l’âge adulte ou chez la personne âgée. Avec une prévalence en hausse, elle constitue aujourd’hui un problème de santé publique, notamment du fait de l’influence de l’environnement sur le génotype.

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In the search for peroxisome proliferator-activated receptor gamma (PPARγ) active constituents from the roots and rhizomes of Notopterygium incisum, 11 new polyacetylene derivatives (1-11) were isolated. Their structures were elucidated by NMR and HRESIMS as new polyyne hybrid molecules of falcarindiol with sesquiterpenoid or phenylpropanoid moieties, named notoethers A-H (1-8) and notoincisols A-C (9-11), respectively. Notoincisol B (10) and notoincisol C (11) represent two new carbon skeletons. When tested for PPARγ activation in a luciferase reporter assay with HEK-293 cells, notoethers A-C (1-3), notoincisol A (9), and notoincisol B (10) showed promising agonistic activity (EC50 values of 1.7 to 2.3 μM). In addition, notoincisol A (9) exhibited inhibitory activity on NO production of stimulated RAW 264.7 macrophages.

This invention relates to an anti-glycation agent comprising aGarcinia kolaextract or fraction. The compositions comprising the extract or the fraction are used to inhibit the glycation of proteins, in particular the glycation of skin proteins involved in cutaneous aging. This invention also relates to a method for determining the activity of compounds for inhibiting the glycation of cutaneous proteins, in particular for inhibiting the glycation of collagen.

International audience

International audience; Advanced glycation end-products (AGEs) are formed during non-enzymatic reactions involving proteins and sugars, i.e. the Maillard or browning reaction. The early glycation is reversible and involves the production of a Schiff base from the carbonyl group of a reducing sugar and the primary amino groups of a protein (lysine, arginine). The imine adduct undergoes a rearrangement yielding Amadori products. During the late stage, complex irreversible oxidation, condensation and cyclisation reactions lead to AGEs via intra- and intermolecular protein crosslinkage.1In diabetes, when the organism can no longer synthesise or properly metabolize insulin, chronic hyperglycaemia induces increased AGE formation and consequently vascular complications. Therefore insulin or oral antidiabetics are used to lower blood sugar levels and to limit the formation of AGEs.1 However, antioxidants acting by radical scavenging or metal chelation as well as compounds capable of trapping dicarbonyl species or breaking AGEs may also reduce the amount of AGEs and diabetic complications.2 As AGEs are also responsible for the aging of many tissues and accumulate in organisms over time, such substances could also be useful for limiting age-related diseases. With this in mind our research focused on the investigation of new AGE inhibitors.In the process we have developed a simple, cheap and high-throughput screening (HTS) assay based on AGE fluorescence, which is highly suitable for the analysis of NPs and extracts. The development of this assay will be presented, and in particular its applicability for the systematic quantification of both vesperlysines and pentosidine-like AGEs will be discussed.1,3By now the main focus of our ongoing project is to identify promising products and plants for future applications as cosmetics and therapeutic agents. Therefore this assay was adapted and patented for the identification of active anti-AGE compounds designated for cosmetic purposes. On the other hand, as anti-AGE compounds are often able to prevent endothelial dysfunction in blood vessels, this HTS assay is also used to select promising NPs and vegetal extracts for further biological applications focusing on the prevention of cardiovascular events4 and graft rejections.References1. L. Séro et al. Tuning a 96-well microtiter plate fluorescence-based assay to identify AGE inhibitors in crude plant extracts. Molecules 2013, 18, 14320-14339 and references therein.2. S. Boisard et al. Chemical composition, antioxidant and anti-AGEs activities of a French poplar type propolis. J. Agric. Food Chem. 2014, 62, 1344-1351 and references therein.3. S. Derbré et al. Automating a 96-well microtiter plate assay for identification of AGEs inhibitors or inducers: application to the screening of a small natural compounds library. Anal. Bioanal. Chem. 2010, 398, 1747-1758.4. B. T. Dang et al. Advanced glycation inhibition and protection against endothelial dysfunction induced by coumarins and procyanidins from Mammea neurophylla. Fitoterapia 2014, 96, 65-75.

International audience; Here, we describe the synthesis of two new fluorescent derivatives of thiamethoxam and compared their toxicity on aphid Acyrthosiphon pisum and their mode of action on insect nicotinic acetylcholine receptors expressed on the sixth abdominal ganglion. The compound 3 with two 2-chlorothiazole moieties was found to be more toxic using toxicological bioassays 24 h and 48 h after exposure while compound 4 appeared more active using cockroach ganglionic depolarization. Interestingly, thiamethoxam appeared more effective than component 3 and 4, respectively. Our results demonstrated that component 3 and 4 act as agonists of insect nicotinic acetylcholine receptors

Article de revue (Article scientifique dans une revue à comité de lecture); International audience; Although different mechanisms have been proposed in the recent years, plant pathogen partial resistance is still poorly understood. Components of the chemical warfare, including the production of plant defense compounds and plant resistance to pathogen-produced toxins, are likely to play a role. Toxins are indeed recognized as important determinants of pathogenicity in necrotrophic fungi. Partial resistance based on quantitative resistance loci and linked to a pathogen-produced toxin has never been fully described. We tested this hypothesis using the Alternaria dauci – carrot pathosystem. Alternaria dauci, causing carrot leaf blight, is a necrotrophic fungus known to produce zinniol, a compound described as a non-host selective toxin. Embryogenic cellular cultures from carrot genotypes varying in resistance against A. dauci were confronted with zinniol at different concentrations or to fungal exudates (raw, organic or aqueous extracts). The plant response was analyzed through the measurement of cytoplasmic esterase activity, as a marker of cell viability, and the differentiation of somatic embryos in cellular cultures. A differential response to toxicity was demonstrated between susceptible and partially resistant genotypes, with a good correlation noted between the resistance to the fungus at the whole plant level and resistance at the cellular level to fungal exudates from raw and organic extracts. No toxic reaction of embryogenic cultures was observed after treatment with the aqueous extract or zinniol used at physiological concentration. Moreover, we did not detect zinniol in toxic fungal extracts by UHPLC analysis. These results suggest that strong phytotoxic compounds are present in the organic extract and remain to be characterized. Our results clearly show that carrot tolerance to A. dauci toxins is one component of its partial resistance.

National audience

National audience; L’endothélium vasculaire joue un rôle central dans le développement des réponses inflammatoires et immunitaires conduisant notamment au phénomène de rejet de greffe1. Les Clusiaceae et Calophyllaceae, plantes des régions pantropicales, biosynthétisent des dérivés polyphénoliques originaux présentant des activités anti-inflammatoires intéressantes2-3. Divers polyphénols isolés de ces plantes ont été sélectionnés, afin d’évaluer in vitro leur potentiel anti-inflammatoire et immunomodulateur sur des cellules endothéliales humaines. Plusieurs coumarines et une benzophénone se sont alors révélées inhibitrices de l’expression de marqueurs de l’inflammation et de l’immunité. Parallèlement à cette étude, les extraits dichlorométhaniques (DCM) et méthanoliques d’un panel de plantes issues des genres Garcinia (Clusiaceae), Calophyllum et Mesua (Calophyllaceae), originaires de Malaisie, ont été analysés par déréplication (HPLC-PDA-MSn). Deux extraits contenant des pharmacophores d’intérêt ont ainsi été sélectionnés pour une étude phytochimique approfondie: l’extrait DCM de fruits de Mesua lepidota, duquel ont été identifiés sept phénylcoumarines originales, que nous avons baptisées lépidotols et lépidotines, et l’extrait DCM de feuille de Calophyllum tetrapterum, ce dernier riche en benzophénones polyprénylées.Références:1. Brick C, Atouf O, Benseffaj N, et al. Rejet de la greffe rénale: mécanisme et prévention. Nephrol Ther 2011;7:18-26.2. Ali M, Arfan M, Ahmad M, et al. Anti-inflammatory xanthones from the twigs of Hypericum oblongifolium Wall. Planta Med 2011;77:2013-2018.3. Santa-Cecilia FV, Freitas LAS, Vilela FC, et al. Antinociceptive and anti-inflammatory properties of 7-epiclusianone, a prenylated benzophenone from Garcinia brasiliensis. Eur J Pharmacol 2011;670:280-285.

Propolis is a resinous substance collected by honeybees from various plant sources. Its secondary metabolites composition depends on the local flora around the collection site. During this study, the chemical characterization of a representative sample of a French propolis produced by ‘‘Ballot-Flurin Apiculteurs’’ led, through structural identifications involving HPLC/DAD/MS as well as 1D & 2D NMR, to the identification of 51 compounds, two of them being new. Phenolic acids and esters and flavonoids identified in this propolis indicate that it belongs to the so-called "poplar" type. The evaluation of the biological activities of different extracts or isolated compounds showed that this propolis, which exhibits a significant antioxidant activity (DPPH and ORAC) associated with a very interesting anti-glycation (anti-AGEs) potential, would represent a good candidate for the prevention of diseases involving AGEs such as diabetes. These extracts or compounds also exhibit antifungal and antibacterial activities towards two Candida yeasts on the one hand, and Staphylococcus aureus and its methicillin-resistant and susceptible strains on the other hand, the latter being nowadays responsible for many nosocomial infections. A study dealing with the inter-batch variability accompanied by an optimization of the industrial extraction process using experimental design were also carried out (Confidential part). Finally, the analysis of three propolis originating from Latin America (Mexico) and Africa (Ivory Coast and Uganda), revealed a great diversity of results in relation to chemical compositions and biological activities., La propolis est une substance résineuse collectée par les abeilles sur certaines parties des végétaux. Sa composition en métabolites secondaires est alors variable puisqu’elle dépend notamment de la flore locale près du site de collecte. Dans cette étude, la caractérisation chimique d’un échantillon représentatif de la propolis française de l’entreprise ‘‘Ballot-Flurin Apiculteurs’’ a conduit, au moyen d’analyses HPLC/DAD/MS et RMN 1D & 2D, à l’identification de 51 composés dont deux sont originaux. Les acides et esters phénoliques ainsi que les flavonoïdes identifiés dans cette propolis indiquent qu’elle appartient au type "peuplier". L’évaluation des activités biologiques de différents extraits et composés isolés a montré que cette propolis, qui possède une bonne activité antioxydante (DPPH et ORAC) associée à un potentiel antiglycant (anti-AGEs) très intéressant, représente un bon candidat pour la prévention des maladies, telles que le diabète, impliquant les AGEs. Elle montre également de bonnes activités antifongiques, sur deux levures du genre Candida, et antibactériennes sur Staphylococcus aureus et ses souches résistantes et sensibles à la méticilline, ces dernières étant responsables, à l’heure actuelle, de nombreuses infections nosocomiales. Une étude de variabilité inter-lots ainsi qu’un travail d’optimisation du procédé d’extraction industriel par plan d’expériences ont également été réalisés (partie confidentielle). Enfin, l’analyse de trois autres propolis, provenant d’Amérique Latine (Mexique) et d’Afrique (Côte d’Ivoire et Ouganda), a montré de grandes diversités de résultats en termes de compositions chimiques et d’activités biologiques.

International audience; Vascular endothelium plays a central role in the development of inflammatory and immune processes, which are involved in graft rejection [1]. Many Clusiaceae/Calophyllaceae species (pantropical plants) biosynthesize original polyphenolic compounds exhibiting antioxidant and anti-inflammatory properties [2 – 3]. Therefore, different Clusiaceae/Calophyllaceae polyphenols were selected in order to evaluate in vitro their anti-inflammatory and immunomodulatory potential towards Human Umbilical Vein Endothelial Cells (HUVECs). The VCAM-1, ICAM-1, E-selectin, HLA-I, HLA-II, HLA-E and MICA surface-expressions of HUVECs were evaluated by flow cytometry. It appeared that a few coumarins and one benzophenone at 10µM significantly inhibited the expression of several markers previously induced by TNF-α or IFN-γ cytokines, being more active that the immunosuppressive reference compound – zoledronic acid – at the same concentration. Among these active compounds, one phenylcoumarin isolated from the Malaysian Mesua lepidota T. Anderson (Calophyllaceae) was identified as a new one. By comparing biological effects with substitution patterns, preliminary structure-activity relationship was also established.

International audience; As summer approaches, a wide selection of plant-based weight-loss supplements arrives on the shelves, including in pharmacies. It is essential, in order to be able to offer informed advice, to know what these products contain and to judge their effectiveness.; À l’approche de l’été, un vaste panel de compléments alimentaires à visée minceur à base de plantes est proposé, y compris dans les officines. Il est capital, dans le cadre d’un conseil avisé, de connaître ce que ces produits contiennent et d’estimer leur efficacité.

Voltage-gated sodium channels (Nav) represent a therapeutically validated group of targets for the development of antiepileptic drugs, analgesics and antiarrhythmics [1]. However most of the existing drugs acting as Nav blockers suffer from multiple side effects, but the existence of a multigene family of Nav [2] suggests that the identification of new compounds that selectively block Nav isoforms might have better therapeutic efficiency and reduced side effects. Due to their molecular interference with numerous ion channels, alkaloids represent a group of natural products of particular interest. This is the reason why we have evaluated the efficiency of an in-house method to screen a library of isoquinoline alkaloids formerly isolated in our laboratory. Mammalian GH3 cells constitutively expressing Nav where used in conjunction with Voltage Sensor Probes (VSPs), the signals being read on a fluorescence plate reader. Thanks to this technique, we were able to precisely detect Nav channels activators or blockers. Among 62 compounds tested, 5 isoquinolines appeared as potent Nav channels inhibitors.References:1. Salat, K. et al. (2014) EOID 23:1093-11042. Yu, F.H. et al (2003) Genome Biol. 4

International audience

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International audience; Vascular endothelium plays a central role in the development of inflammatory and immune processes, which are involved in graft rejection1. Many Clusiaceae/Calophyllaceae species (pantropical plants) biosynthesize original polyphenolic compounds exhibiting antioxidant and anti-inflammatory properties2-3. Bark, leaves and occasionally fruits from thirteen Malaysian plants belonging to the genus Calophyllum, Mesua (Calophyllaceae), Garcinia (Clusiaceae) were extracted using DCM and MeOH as the solvents. Each extract was then submitted to a HPLC-PDA-MSn dereplication analysis and its anti-inflammatory potential was evaluated on Human Umbilical Vein Endothelial Cells (HUVECs). This allowed to select the bioactive fruits DCM extract of Mesua lepidota T. Anderson for an advanced phytochemical study, which led to the identification of several new coumarin derivatives. A flow cytometry study revealed that the major component of this extract, namely lepidotol A (1), significantly inhibited the VCAM-1, HLA-II and HLA-E expression of HUVECs previously activated by TNF-α or IFN-γ cytokines.References1. P. T. Clesca, Int. Congr. Ser., 2002, 1237, 181-191.2. F. V. Cechinel, C. Meyre-Silva, and R. Niero, Chem. Biodivers., 2009, 6, 313-327.3. J. González-Gallego, M. V. García-Mediavilla, S. Sánchez-Campos and M. J. Tuñón, Br. J. Nutr., 2010, 104, S15-S27

International audience; Endothelial cells (ECs) are key players in inflammation and immune responses involved in numerous pathologies. Although attempts were experimentally undertaken to prevent and control EC activation, drug leads and probes still remain necessary. Natural products (NPs) from Clusiaceous and Calophyllaceous plants were previously reported as potential candidates to prevent endothelial dysfunction. The present study aimed to identify more precisely the molecular scaffolds that could limit EC activation. Here, 13 polyphenols belonging to 5 different chemical types of secondary metabolites (i.e., mammea coumarins, a biflavonoid, a pyranochromanone acid, a polyprenylated polycyclic acylphloroglucinol (PPAP) and two xanthones) were tested on resting and cytokine-activated EC cultures. Quantitative and qualitative changes in the expression of both adhesion molecules (VCAM-1, ICAM-1, E-selectin) and major histocompatibility complex (MHC) molecules have been used to measure their pharmaceutical potential. As a result, we identified 3 mammea coumarins that efficiently reduce (up to >90% at 10 μM) both basal and cytokine-regulated levels of MHC class I, class II, MICA and HLA-E on EC surface. They also prevented VCAM-1 induction upon inflammation. From a structural point of view, our results associate the loss of the free prenyl group substituting mammea coumarins with a reduced cellular cytotoxicity but also an abrogation of their anti-inflammatory potential and a reduction of their immunosuppressive effects. A PPAP, guttiferone J, also triggers a strong immunomodulation but restricted to HLA-E and MHC class II molecules. In conclusion, mammea coumarins with a free prenyl group and the PPAP guttiferone J emerge as NPs able to drastically decrease both VCAM-1 and a set of MHC molecules and to potentially reduce the immunogenicity of the endothelium.

International audience; Glioblastoma (GB) displays diffusely infiltrative growth patterns. Dispersive cells escape surgical resection and contribute to tumour recurrence within a few centimeters of the resection cavity in 90% of cases. We know that the non-neoplastic stromal compartment, in addition to infiltrative tumour cells, plays an active role in tumour recurrence. We isolated a new stromal cell population from the histologically normal surgical margins of GB by computer-guided stereotaxic biopsies and primary culture. These GB-associated stromal cells (GASCs) share phenotypic and functional properties with the cancer-associated fibroblasts (CAFs) described in the stroma of carcinomas. In particular, GASCs have tumour-promoting effects on glioma cells in vitro and in vivo. Here, we describe a quantitative proteomic analysis, using iTRAQ labelling and mass spectrometry, to compare GASCs with control stromal cells derived from non-GB peripheral brain tissues. A total of 1077 proteins were quantified and 67 proteins were found to differ between GASCs and control stromal cells. Several proteins changed in GASCs are related to a highly motile myofibroblast phenotype, and to wound healing and angiogenesis. The results for several selected proteins were validated by western blotting or flow cytometry. Furthermore, the effect of GASCs on angiogenesis was confirmed using the orthotopic U87MG glioma model. In conclusion, GASCs, isolated from GB histologically normal surgical margins and found mostly near blood vessels, could be a vascular niche constituent establishing a permissive environment, facilitating angiogenesis and possibly colonization of recurrence-initiating cells. We identify various proteins as being expressed in GASCs: some of these proteins may serve as prognostic factors for GB and/or targets for anti-glioma treatment.

Self-assembled monolayers (SAMs) that contain fluorophore units are nowadays widely used to tune surface properties and design new chemical sensor chips. It is well-known that the nature of the substrate may strongly interfere with the emission properties of the grafted molecules, but the organization of the monolayer may also have an important role. To study the influence of the SAM organization on the luminescence properties, we prepared different coumarin-based derivatives endowed with tethered chains of different lengths and elaborated the corresponding SAMs on glass slides. Besides SAM structural characterizations by atomic force microscopy and X-ray reflectivity, we carried out contact angle measurements and applied the Van Oss-Chaudhury-Good theory, which was rarely used previously for self-assembled monolayers. As expected, by increasing the tethered chain length, a higher surface coverage, a higher degree of organization, and a stronger molecular packing were observed. However, it appears to facilitate the self-quenching process, and thus, this strongly affects the fluorescent properties of the SAMs.

In relation to their antioxidant potential, phenolic compounds are usually associated with a protective effect on the human health of a diet rich in fruits and vegetables. They are also widely associated to the organoleptic quality of ciders since they affect bitterness, astringency, color and aroma. Two studies have recently been published on QTL detection for the phenolic content of dessert apple. No study has yet been published for cider apple, even though they are usually more concentrated in phenolic compounds The objective of this work was to identify genomic regions involved in the phenolic content for a cider apple progeny. In a first time, two quantification methods were developed and compared in UHPLC-UV and UHPLC-MS/MS for major phenolic compounds in juices. Even overestimation of some compounds with one detector were observed, these two methods were highly correlated. Phenolic compounds of whole fruits were also quantified at the INRA station of Rennes. A high variability was observed in both fruits and juices of this progeny, representative of major cider apple varieties grown in Europe. 48 QTL were detected on nine linkage groups (LG). Nine clusters seem particularly stable according to the year or material study. Enzymes of the polyphenol pathway and transcription factors were targeted as candidate gene and identified in silico under major QTL. This work offers new targets for the marker-assisted selection like the QTL for chlorogenic acid on LG17 to improve cider apple varieties.; En lien avec leur potentiel antioxydant, les composés phénoliques sont généralement associés à l'effet protecteur sur la santé d'une alimentation riche en fruits et légumes. Ils sont également fortement associés à la qualité organoleptique des cidres puisqu'ils affectent directement leur astringence, leur amertume, leur couleur et leurs arômes. Deux études ont récemment été publiées sur la détection de QTL des composés phénoliques des pommes de table. Aucune étude n'a encore été publiée pour les pommes à cidre, réputées pour leur forte teneur en composés phénoliques. L'objectif de cette thèse est d'identifier les régions génétiques impliquées dans la teneur en composés phénoliques d'une descendance de pommiers à cidre. Dans un premier temps, deux méthodes de quantification ont été développées et comparées en UHPLC-UV et UHPLC-MS/MS pour les principaux composés phénoliques du jus de pomme. Bien qu'il y ait des surestimations avec l'un des détecteurs pour certains composés, ces deux méthodes corrèlent très fortement. Des dosages ont également été réalisés sur fruit entier à l'INRA de Rennes. Une grande variabilité a été observée pour les fruits et les jus de cette descendance, représentative des principales variétés de pommes à cidre cultivées en Europe. 48 QTL ont été détectés sur neuf groupes de liaison (LG). Neuf clusters semblent particulièrement stables, indépendamment de l'année ou du matériel (fruit ou jus) étudié. Les enzymes de la biosynthèse des composés phénoliques et facteurs de transcription ont été ciblés pour l'identification des gènes candidats, réalisée au niveau des principaux QTL. Ces travaux proposent de nouvelles cibles pour la sélection assistée par marqueurs comme le QTL pour l'acide chlorogénique du LG17 pour l'amélioration des variétés de pommes à cidre

International audience; Ternary assemblies of β-cyclodextrin with cholecalciferol (or vitamin D3) or phenothiazine and Al3+ ions were studied. The stability constants of aluminium binary complexes with cholecalciferol or phenothiazine and of ternary assemblies (β-cyclodextrin, cholecalciferol or phenothiazine and Al3+) were determined using potentiometric titrations at 25 °C (I = 0.100 M). The 13C NMR spectra of the supramolecular structures in the solid state showed that ternary supramolecular structures associating β-cyclodextrin, cholecalciferol or phenothiazine and aluminium(III) ions were obtained. Finally, X-ray powder diffraction patterns showed that the ternary assemblies with phenothiazine are channel type inclusion complexes.

In this study, the physiological functions of fungal mannitol metabolism in the pathogenicity and protection against environmental stresses were investigated in the necrotrophic fungus Alternada brassicicola. Mannitol metabolism was examined during infection of Brass/ca oleracea leaves by sequential HPLC quantification of the major soluble carbohydrates and expression analysis of genes encoding two proteins of mannitol metabolism, i.e., a mannitol dehydrogenase (AbMdh), and a mannito1-1-phosphate dehydrogenase (AbMpd). Knockout mutants deficient for AbMdf7 or AbMpd and a double mutant lacking both enzyme activities were constructed. Their capacity to cope with various oxidative and drought stresses and their pathogenic behavior were evaluated. Metabolic and gene expression profiling indicated an increase in mannitol production during plant infection. Depending on the mutants, distinct pathogenic processes, such as leaf and silique colonization, sporulation, survival on seeds, were impaired by comparison to the wild-type. This pathogenic alteration could be partly explained by the differential susceptibilities of mutants to oxidative and drought stresses. These results highlight the importance of mannitol metabolism with respect to the ability of A. brassicrcola to efficiently accomplish key steps of its pathogenic life cycle.

International audience; Naturally occurring hydroxamic acid derivatives are biosynthesized by microorganisms (siderophores) and plants (benzoxazinoids). Recent developments in drug discovery have highlighted the numerous biological and pharmacological properties that the hydroxamic acid function may possess, leading to therapeutic applications. These properties may be explained by its ability to chelate metals via the presence of two oxygen atoms. Their pharmacological activities can be divided into three groups. The first concerns the ability of these hydroxamic acid derivatives to scavenge metals (particularly iron), which leads to antioxidant, antimicrobial and metal detoxification activities. The latter is largely used to treat iron overload in patients. The second group of activities is related to their ability to inhibit metallo-enzymes, which gives them a wide range of pharmacological effects: antimicrobial, anti-inflammatory and antitumor. The third group is linked to the capacity of these compounds to generate nitric oxide, which confers hypotensive activity. However, hydroxamates exhibit relatively low stability in vivo, which can be overcome by the synthesis of appropriately designed analogs. For this purpose, many different strategies have been proposed. In this review, we compare and discuss the various synthetic pathways used to obtain the most complex of them, the N-substituted hydroxamic acids. We conclude that among numerous protocols reported so far, the direct N-substitution of hydroxamic acids, the acylation of the appropriate N-O derivative and the direct oxidation of the corresponding amide allow for the synthesis of a wide range of new biologically active compounds.

Streptococcus pyogenesplays an important role in the pathogenesis of tonsillitis. The present study was conducted to evaluate thein vitroantibacterial activities of 18 essential oils chemotypes from aromatic medicinal plants againstS. pyogenes. Antibacterial activity of essential oils was investigated using disc diffusion method. Minimum Inhibitory Concentration of essential oils showing an important antibacterial activity was measured using broth dilution method. Out of 18 essential oils tested, 14 showed antibacterial activity againstS. pyogenes. Among themCinnamomum verum, Cymbopogon citratus, Thymus vulgaris CT thymol, Origanum compactum, andSatureja montanaessential oils exhibited significant antibacterial activity. Thein vitroresults reported here suggest that, for patients suffering from bacterial throat infections, if aromatherapy is used, these essential oils, considered as potential antimicrobial agents, should be preferred.

The present invention relates to (i) a method of analysing small molecules that may have a mass of < 800 Da, in particular alkaloids, said method being generally referred to as MALDI-TOF-MS (or MALDI Time-of-Flight MAss Spectrometry) which is an acronym for a method of analysis by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry, to (ii) a molecule according to formula (I) and to the use thereof as a matrix in such an analysis method.; La présente invention se rapporte à (i) une méthode d'analyse de petites molécules pouvant avoir une masse < 800 Da, en particulier des alcaloïdes, ladite méthode étant généralement désignée sous le nom de MALDI-TOF-MS (ou spectrométrie de masse à temps de vol MALDI) qui est un acronyme pour méthode d'analyse par spectrométrie de masse à temps de vol à désorption/ionisation sous laser assistée par matrice, à (ii) une molécule de formule (I) et à son utilisation comme matrice dans une telle méthode d'analyse.

International audience; Introduction: Propolis, or bee glue, is a natural resinous hive product collected by honeybees from buds and exudates of various trees and plants. Mixed with beewax and salivary enzymes, it is employed to fill cracks and embalm dead invaders in the hive. Several studies about mexican propolis have revealed chemical profiles where cinnamic and phenylpropanoic acid derivatives as well as flavonoids dominated, whereas these extracts exhibited cytotoxic and/or antifungal activities. Research methods: An ethanolic extract of a batch of mexican propolis, collected in the state of Quintana Roo, Mexico, was first analysed by High Performance Liquid Chromatography coupled with Diode Array Detector (HPLC/DAD) but no major components could be detected. Its antioxidant activity was evaluated by 1,1-diPhenyl-2-PicrylHydrazyl (DPPH) assay as well, and its antibacterial (against 21 Gram-positive and Gram-negative strains including Staphyloccocus aureus) and antifungal (against Candida albicans and Aspergillus fumigatus) properties were evaluated through microdilution assays. Then, this extract was fractionated by Flash chromatography. Three of the fractions, containing the major constituents, were analysed by Gas Chromatography coupled with Mass Spectrometry (GC/MS). Results and discussion: This Mexican propolis did not show any antioxidant neither antibacterial nor antifungal activity. The main constituents of this Mexican propolis were identified as triterpenes (amyrenone, amyrin and amyrin-3-acetate) and sterols (fucosterol and sistosterol). This unusual composition associated with a Mexican propolis would thus explain the lack of biological activities. Further investigations will be conducted in order to link this chemical composition with the propolis plant sources.

International audience