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Rene Lafont - One of the best experts on this subject based on the ideXlab platform.
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small scale analysis of Phytoecdysteroids in seeds by hplc dad ms for the identification and quantification of specific analogues dereplication and chemotaxonomy
Phytochemical Analysis, 2020Co-Authors: Laurence Dinan, Christine Balducci, Louis Guibout, Rene LafontAbstract:INTRODUCTION: Phytoecdysteroids are analogues of arthropod steroids occurring in plants. They contribute to invertebrate deterrence. A wide diversity of ecdysteroids occurs in phytoecdysteroid‐containing plant species, sometimes in high amounts. Ecdysteroids demonstrate potentially useful pharmaceutical actions in mammals. OBJECTIVES: Establish reversed‐phase high‐performance liquid chromatography with tandem mass spectrometry (RP‐HPLC‐MS/MS) and RP‐HPLC‐DAD‐MS (diode array detector mass spectrometry) methods for the separation, identification and quantification of ecdysteroids to screen for species containing significant amounts of 20‐hydroxyecdysone (20E) and other useful ecdysteroids. MATERIALS AND METHODS: Micro‐extracts of seed samples (ca. 30 mg) in 50% ethanol were subjected to RP‐SPE (solid‐phase extraction) purification prior to analysis by RP‐HPLC‐MS/MS and RP‐HPLC‐DAD‐MS. The method was initially applied to genera (Amaranthus, Centaurea, Lychnis, Ourisia, Serratula, Silene and Trollius) where high‐accumulating species had been previously encountered. Seeds of 160 randomly selected species, many of which have not previously been assessed, were then analysed. HPLC‐MS/MS with a short analysis time initially identifies ecdysteroid‐positive extracts and quantifies 20E. The positive extracts (20 ng 20E) are then analysed by HPLC‐MS/MS with a longer analysis time to identify and quantify 17 common Phytoecdysteroids and, finally, HPLC‐DAD‐MS (0.1–0.25 μg 20E) is used to obtain UV‐ and MS‐spectra to confirm identifications or as a basis for characterisation of partially identified or novel analogues. RESULTS: Lychnis coronaria, Silene fimbriata and Silene hookeri ecdysteroids are characterised for the first time and those of Cucubalus baccifer and Ipheion uniflorum are more extensively characterised. CONCLUSIONS: The procedure provides a rapid/sensitive method for screening small plant samples for the presence, quantification and identification of ecdysteroids. It permits ready dereplication of samples, identifying extracts containing large amounts or novel analogues.
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E- and Z-Isomers of New Phytoecdysteroid Conjugates from French Polynesian Microsorum membranifolium (Polypodiaceae) Fronds
Molecules, 2012Co-Authors: Jean-pierre Girault, Phila Raharivelomanana, Rene LafontAbstract:Phytochemical investigation of the fronds of Microsorum membranifolium resulted in the isolation of a new phytoecdysteroid, E-2-deoxy-20-hydroxyecdysone 3-[4-(1-β-D-glucopyranosyl)]-caffeate (1), together with two known Phytoecdysteroids, E-2-deoxy-20-hydroxyecdysone 3-[4-(1-β-D-glucopyranosyl)]-ferulate (2), E-2-deoxyecdysone 3-[4-(1-β-D-glucopyranosyl)]-ferulate (3). Their respective Z-isomers 4-6 were also observed and identified for the first time. The new structures were elucidated on the basis of extensive spectroscopic data analysis (1D, 2D-NMR and HR-MS techniques).
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dietary effects of four Phytoecdysteroids on growth and development of the indian meal moth plodia interpunctella
Journal of Insect Science, 2010Co-Authors: Kacem Rharrabe, Fouad Sayah, Rene LafontAbstract:Using pure Phytoecdysteroids isolated from Ajuga iva (L.) Schreber (Lamiales: Lamiaceae) and Silene nutans L. (Caryophyllales: Caryophyllaceae), plants known for their high ecdysteroid content, a study was carried out on the effects of ingestion of four different Phytoecdysteroids (20-hydroxyecdysone, polypodine B, ponasterone A and makisterone A) on the growth and development of the Indian meal moth, Plodia interpunctella Hubner (Lepidoptera: Pyralidae) larvae when added at a concentration of 200 ppm in their diet. The experiments clearly showed the susceptibility of P. interpunctella to phytoecdysteroid ingestion. The toxicity of Phytoecdysteroids manifested itself by a decrease in larval weight, induction of cannibalism and an increase of mortality, together with disruption of development. The severity of the phytoecdysteroid effect on P. interpunctella depended on the structure of the molecule. The results demonstrate that the minimal structural differences existing between these four Phytoecdysteroids significantly affected their toxicity toward P. interpunctella. Makisterone A was the most toxic of the four compounds towards P. interpunctella larvae. In conclusion, Phytoecdysteroids ingestion evokes disruptive growth effects on P. interpunctella. This work supports a role for Phytoecdysteroids in plant defence against phytophagous insects.
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Phytoecdysteroids in the Genus Microsorum (Polypodiaceae) of French Polynesia
Natural Product Communications, 2007Co-Authors: Taivini Teai, Rene Lafont, Jean-pierre Girault, Denis Loquet, Jean-pierre Bianchini, Phila RaharivelomananaAbstract:A chemical survey of the six species of Microsorum in French Polynesia has been performed to determine and quantify the Phytoecdysteroids. The content and composition of these compounds in the fron...
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Distribution of Phytoecdysteroids in the Caryophyllaceae.
Phytochemistry, 2003Co-Authors: L. N. Zibareva, Rene Lafont, Tamara Savchenko, Pensri Whiting, Vladimir A. Volodin, Zyadilla Saatov, Laurence DinanAbstract:Abstract Certain genera within the Caryophyllaceae (especially Silene and Lychnis) have received a significant amount of attention with regard to the isolation and identification of ecdysteroids. However, the taxonomy of this family is difficult. Hence, the occurrence of Phytoecdysteroids in members of the Caryophyllaceae is presented, and combined with new data on ecdysteroid agonist (phytoecdysteroid) and antagonist activities, in order to survey the distribution of phytoecdysteroid-containing species within this large family, and to assess the utility of Phytoecdysteroids as chemotaxonomic markers. The new data presented (representing ca. 110 species) have been obtained by the application of sensitive biological/biochemical methods for the detection of ecdysteroid agonists and antagonists, using Drosophila melanogaster BII bioassay and ecdysteroid-specific immunoassays. In the antagonist version of the BII bioassay, only weak ecdysteroid antagonist activities were detected in a few of the extracts. From both new and previously available data, it was found that Phytoecdysteroids were present predominantly in the Genera Lychnis, Petrocoptis, Sagina and Silene. Comparison of ecdysteroid occurrence with a molecular phylogeny for the tribe Sileneae [Taxon 44 (1995) 525] revealed close association of ecdysteroid occurrence with certain groups of this tribe. In 14 species of Silene examined, there is a reasonable, but not absolute, relationship between the presence of ecdysteroids in the seeds and in other plant parts. Where ecdysteroids are present in the plant, highest concentrations are generally present in the roots.
Ilya Raskin - One of the best experts on this subject based on the ideXlab platform.
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Quinoa seeds leach Phytoecdysteroids and other compounds with anti-diabetic properties.
Food chemistry, 2014Co-Authors: Brittany L. Graf, Mary Ann Lila, Mary H. Grace, Alexander Poulev, Peter Kuhn, Ilya RaskinAbstract:Quinoa (Chenopodium quinoa Willd.) contains high levels of biologically active Phytoecdysteroids, which have been implicated in plant defense from insects, and have shown a range of beneficial pharmacological effects in mammals. We demonstrated that the most prevalent phytoecdysteroid, 20-hydroxyecdysone (20HE), was secreted (leached) from intact quinoa seeds into water during the initial stages of seed germination. Leaching efficiency was optimized by ethanol concentration (70% ethanol), temperature (80°C), time (4h), and solvent ratio (5 ml/g seed). When compared to extraction of macerated seeds, the leaching procedure released essentially all the 20HE available in the seeds (491 μg/g seed). The optimized quinoa leachate (QL), containing 0.86% 20HE, 1.00% total Phytoecdysteroids, 2.59% flavonoid glycosides, 11.9% oil, and 20.4% protein, significantly lowered fasting blood glucose in obese, hyperglycemic mice. Leaching effectively releases and concentrates bioactive phytochemicals from quinoa seeds, providing an efficient means to produce a food-grade mixture that may be useful for anti-diabetic applications.
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ecdysteroids elicit a rapid ca2 flux leading to akt activation and increased protein synthesis in skeletal muscle cells
Steroids, 2010Co-Authors: Jonathan Gorelickfeldman, Wendie S Cohick, Ilya RaskinAbstract:Phytoecdysteroids, structurally similar to insect molting hormones, produce a range of effects in mammals, including increasing growth and physical performance. In skeletal muscle cells, Phytoecdysteroids increase protein synthesis. In this study we show that in a mouse skeletal muscle cell line, C(2)C(12), 20-hydroxyecdysone (20HE), a common phytoecdysteroid in both insects and plants, elicited a rapid elevation in intracellular calcium, followed by sustained Akt activation and increased protein synthesis. The effect was inhibited by a G-protein coupled receptor (GPCR) inhibitor, a phospholipase C (PLC) inhibitor, and a phosphoinositide kinase-3 (PI3K) inhibitor.
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Phytoecdysteroids increase protein synthesis in skeletal muscle cells.
Journal of agricultural and food chemistry, 2008Co-Authors: Jonathan Gorelick-feldman, Diana M. Cheng, Mary Ann Lila, Alexander Poulev, David B. Maclean, Nebojša Ilić, Ilya RaskinAbstract:Phytoecdysteroids, which are structurally similar or identical to insect molting hormones, produce a range of effects in mammals, including increasing growth and physical performance. To study the mechanism of action of Phytoecdysteroids in mammalian tissue, an in vitro cellular assay of protein synthesis was developed. In C2C12 murine myotubes and human primary myotubes, Phytoecdysteroids increased protein synthesis by up to 20%. In vivo, ecdysteroids increased rat grip strength. Ecdysteroid-containing plant extracts produced similar results. The effect was inhibited by a phosphoinositide kinase-3 inhibitor, which suggests a PI3K-mediated mechanism.
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In vitro production of metabolism-enhancing Phytoecdysteroids from Ajuga turkestanica
Plant Cell Tissue and Organ Culture, 2008Co-Authors: Diana M. Cheng, Gad G. Yousef, Mary H. Grace, Randy B. Rogers, Jonathan Gorelick-feldman, Ilya Raskin, Mary Ann LilaAbstract:In order to develop a sustainable source of metabolism-enhancing Phytoecdysteroids, cell suspension and hairy root cultures were established from shoot cultures of wild-harvested Ajuga turkestanica, a medicinal plant indigenous to Uzbekistan. Precursors of Phytoecdysteroids (acetate, mevalonic acid cholesterol) or methyl jasmonate (an elicitor) were added to subculture media to increase phytoecdysteroid accumulation. In cell suspension cultures, 20-hydroxyecdysone (20E) content increased 3- or 2-fold with the addition of 125 or 250 μM methyl jasmonate, respectively, compared to unelicited cultures. Precursor addition, however, did not provoke phytoecdysteroid accumulation. In hairy root cultures, addition of sodium acetate, mevalonic acid, and methyl jasmonate, but not cholesterol, increased phytoecdysteroid content compared to unelicited cultures. Hairy root cultures treated with 150 mg l−1 sodium acetate, or 15 or 150 mg l−1 mevalonic acid, increased 20E content approximately 2-fold to 19.9, 20.4 or 21.7 μg mg−1, respectively, compared to control (10.5 μg mg−1). Older hairy root cultures, extracted after the seventh subculture cycle, also showed increases in 20E content (24.8 μg mg−1), turkesterone (0.9 μg mg−1) and cyasterone (8.1 μg mg−1) compared to control cultures maintained for a shorter duration of four subculture cycles. Doses of 10 or 20 μg ml−1 hairy root extract increased protein synthesis by 25.7% or 31.1%, respectively, in a C2C12 mouse skeletal cell line. These results suggest that sustainable production of metabolically active phytoecdysteroid can be achieved through hairy root culture systems.
Jean-pierre Girault - One of the best experts on this subject based on the ideXlab platform.
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E- and Z-Isomers of New Phytoecdysteroid Conjugates from French Polynesian Microsorum membranifolium (Polypodiaceae) Fronds
Molecules, 2012Co-Authors: Jean-pierre Girault, Phila Raharivelomanana, Rene LafontAbstract:Phytochemical investigation of the fronds of Microsorum membranifolium resulted in the isolation of a new phytoecdysteroid, E-2-deoxy-20-hydroxyecdysone 3-[4-(1-β-D-glucopyranosyl)]-caffeate (1), together with two known Phytoecdysteroids, E-2-deoxy-20-hydroxyecdysone 3-[4-(1-β-D-glucopyranosyl)]-ferulate (2), E-2-deoxyecdysone 3-[4-(1-β-D-glucopyranosyl)]-ferulate (3). Their respective Z-isomers 4-6 were also observed and identified for the first time. The new structures were elucidated on the basis of extensive spectroscopic data analysis (1D, 2D-NMR and HR-MS techniques).
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Phytoecdysteroids in the Genus Microsorum (Polypodiaceae) of French Polynesia
Natural Product Communications, 2007Co-Authors: Taivini Teai, Rene Lafont, Jean-pierre Girault, Denis Loquet, Jean-pierre Bianchini, Phila RaharivelomananaAbstract:A chemical survey of the six species of Microsorum in French Polynesia has been performed to determine and quantify the Phytoecdysteroids. The content and composition of these compounds in the fron...
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ecdysteroids from ajuga iva
Phytochemistry, 1992Co-Authors: Marc Wessner, Jean-pierre Girault, Brigitte Champion, Naguib Kaouadji, Bassima Saidi, Rene LafontAbstract:Abstract Ajuga iva contains large amounts of three major ecdysteroids (makisterone A, 20-hydroxyecdysone and cyasterone) together with several minor compounds including 24,28-dehydromakisterone A and two new Phytoecdysteroids (22-oxocyasterone and 24,25-dehydroprecyasterone) which have been identified by spectrometric procedures.
Katarzyna Dzitko - One of the best experts on this subject based on the ideXlab platform.
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and
2016Co-Authors: Katarzyna Dzitko, Bozena Dziadek, Justyna Gatkowska, Paweł Stączek, Marcin Mikołaj Grzybowski, Jakub Pawełczyk, Henryka DługońskaAbstract:Phytoecdysteroids as modulators of the Toxoplasma gondii growth rate in huma
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Phytoecdysteroids as modulators of the Toxoplasma gondii growth rate in human and mouse cells
Parasites & vectors, 2015Co-Authors: Katarzyna Dzitko, Marcin M. Grzybowski, Jakub Pawelczyk, Bozena Dziadek, Justyna Gatkowska, Paweł Stączek, Henryka DługońskaAbstract:Background Searching for new effective drugs against human and animal toxoplasmosis we decided to test the anti-Toxoplasma potential of Phytoecdysteroids (α-ecdysone and 20-hydroxyecdysone) characterized by the pleiotropic activity on mammalian organisms including the enhancement of host’s anti-parasitic defence. This objective was accomplished by the in vitro evaluation of T. gondii growth in phytoecdysteroid-treated immunocompetent cells of selected hosts: humans and two strains of inbred mice with genetically determined different susceptibility to toxoplasmosis.
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Phytoecdysteroids as modulators of the toxoplasma gondii growth rate in human and mouse cells
Parasites & Vectors, 2015Co-Authors: Katarzyna Dzitko, Marcin M. Grzybowski, Jakub Pawelczyk, Bozena Dziadek, Justyna Gatkowska, Paweł Stączek, Henryka DlugonskaAbstract:Searching for new effective drugs against human and animal toxoplasmosis we decided to test the anti-Toxoplasma potential of Phytoecdysteroids (α-ecdysone and 20-hydroxyecdysone) characterized by the pleiotropic activity on mammalian organisms including the enhancement of host’s anti-parasitic defence. This objective was accomplished by the in vitro evaluation of T. gondii growth in phytoecdysteroid-treated immunocompetent cells of selected hosts: humans and two strains of inbred mice with genetically determined different susceptibility to toxoplasmosis. Peripheral mononuclear blood cells were isolated from Toxoplasma-positive and Toxoplasma-negative women (N = 43) and men (N = 21). Non-infected mice (C57BL/6, N = 10 and BALB/c, N = 14) and mice (BALB/c, N = 10) challenged intraperitoneally with 5 tissue cysts of the T. gondii DX strain were also used in this study as a source of splenocytes. The effects of Phytoecdysteroids on the viability of human PBMC and mouse splenocytes were evaluated using the MTT assay. The influence of Phytoecdysteroids on PBMCs, splenocytes and T. gondii proliferation was measured using radioactivity tests (the level of 3[H] uracil incorporation by toxoplasms or 3[H] thymidine by PBMCs and splenocytes), which was confirmed by quantitative Real-Time PCR. Statistical analysis was performed using SigmaStat 3.5 (Systat Software GmbH). The best-fit IC50 curves were plotted using GraphPad Prism 6.0 (GraphPad Software, Inc.). Our results showed that Phytoecdysteroids promote the multiplication of Toxoplasma in cultures of human or murine immune cells, in contrast to another apicomplexan parasite, Babesia gibsoni. Additionally, the tested Phytoecdysteroids did not stimulate the in vitro secretion of the essential protective cytokines (IFN-γ, IL-2 and IL-10), neither by human nor by murine immune cells involved in an effective intracellular killing of the parasite. Judging by the effect of Phytoecdysteroids on the T. gondii proliferation, demonstrated for the first time in this study, it seems that these compounds should not be taken into consideration as potential medications to treat toxoplasmosis. Phytoecdysteroids included in the food are most likely not harmful for human or animal health but certain nutrients containing ecdysteroids at high concentrations could promote T. gondii proliferation in chronically infected and immunocompromised individuals. In order to assess the real impact of ecdysteroids on the course of natural T. gondii invasion, in vivo research should be undertaken because it cannot be ruled out that the in vivo effect will be different than the in vitro one. However, taking into account the possible stimulating effect of ecdysteroids on some opportunistic parasites (such as Toxoplasma or Strongyloides) further studies are necessary and should focus on the mechanisms of their action, which directly or indirectly enhance the parasite growth. Since ecdysteroids are considered as potential drugs, it is essential to determine their effect on various parasitic pathogens, which may infect the host at the same time, especially in immunocompromised individuals.
K. Srivastava - One of the best experts on this subject based on the ideXlab platform.
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PHYTOECDYSTEROID CHANGES AMINO ACID CONTENT IN THE LARVAE OF BOMBYX MORI
2014Co-Authors: K. Srivastava, V. B. UpadhyayAbstract:Phytoecdysteroids affect the total amino acid content in the silkgland of fifth instar larvae of Bombyx mori at the initial stage (P2 < 0.05) and final stage of spinning. The amino acid content increased with increase in phytoecdysteroid concentration and number of larval treatment but with triple treatment of 70% concentration the amino acid content was decreased.The Phytoecdysteroids may prove to be a boon for increased silk production.
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Effect of Phytoecdysteroid on Incubation Period and Per Cent Fertilized Egg of Multivoltine Mulberry Silkworm Bombyx mori Linn.
2013Co-Authors: K. SrivastavaAbstract:Effect of phytoecdysteroid on incubation period and per cent fertilized egg of multivoltine mulberry silkworm Bombyx mori was studied. Variation in the phytoecdysteroid concentration and number of larval treatment(treated the larvae) influenced the incubation period and per cent fertilized egg of Bombyx mori eggs. In 40, 50 and 60% phytoecdysteroid concentration, the incubation period decreased slowly and slowly, in single(treated the V instar larvae onlyone times just before two days of larval spinning) and double th phytoecdysteroid concentration in all the treatment caused considerable increase in the incubation period of eggs. The minimum incubation period was noticed (7.95 ± 0.180) days in case of double treatment by 60% phytoecdysteroid concentration. Maximum per cent fertilized egg was noticed (94.75 ± 2.03) in case of double treatment by 60% phytoecdysteroid concentration. Experiments were performed by different concentration of phytoecdysteroid obtained from Achyranthes leaf extract. A control set was always maintained with each set of experiment. Number of larval treatment and variation in the phytoecdysteroid concentration did not cause significant effect on the incubation period of egg as the economy of Bombyx mori. Two-way ANOVA indicates that number of larval treatment significantly (P < 0.01) influenced the percentage of fertilized egg. 2 Phytoecdysteroid treatment, if applied tactfully, may be useful for boosting up the sericulture industry as well as the economy of silkworm rearing.
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effect of phytoecdysteroid on silk producing poten tial of multivoltine mulberry silkworm bombyx mori linn
2013Co-Authors: K. Srivastava, V. B. UpadhyayAbstract:Effect of phytoecdysteroid on silk producing potential of multivoltine mulberry silkworm Bombyx mori was studied. Experiments were performed by 40, 50, 60 and 70% concentration of phytoecdysteroid obtained from Achyranthes leaf extract. A control set was always maintained with each set of experiment. Maximum shell ratio (15.45 ± 1.07) was noticed to be in case of the double treatment (IV and V instar larvae were treated) by 60% phytoecdysteroid and minimum (12.25 ± 0.831) was recorded in triple treatment (III, IV and V instar larvae were treated) by 70% phytoecdysteroid concentration. Phytoecdysteroid treatment,if applied tactfully,may be useful for boosting up the sericulture industry as well as the economy of silkworm rearing.
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effect of phytoecdysteroid on fecundity of multivoltine mulberry silkworm bombyx mori linn
2013Co-Authors: K. SrivastavaAbstract:Effect of phytoecdysteroid on fecundity and hatchability of multivoltine mulberry silkworm Bombyx mori was studied. Experiments were performed by 40, 50, 60 and 70% concentration of phytoecdysteroid obtained from Achyranthes leaf extract. A control set was always maintained with each set of experiment.The parameter selected for observation was fecundity of Bombyx mori. Maximum fecundity (423.33 ± 4.67) was noticed to be in case of the double treatment (IV and V instar larvae were treated) by 60% phytoecdysteroid concentration. Phytoecdysteroid treatment,if applied tactfully,may be useful for boosting up the sericulture industry as well as the economy of silkworm rearing.
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Influence of Phytoecdysteroid on Weight of Ovary and Weight of Egg of Multivoltine Mulberry Silkworm Bombyx mori Linn
2012Co-Authors: K. SrivastavaAbstract:Effect of phytoecdysteroid on weight of ovary and weight of egg of multivoltine mulberry silkworm Bombyx mori was studied. Variation in the phytoecdysteroid concentration and number of larval treatment (treated the larvae) influenced the weight of ovary and weight of B. mori eggs. Experiments were performed by 40, 50, 60 and 70% concentration of phytoecdysteroid obtained from Achyranthes leaf extract. A control set was always maintained with each set of experiment. Number of larval treatment significantly (P < 0.05) 2 influenced the weight of ovary and weight of egg. Maximum weight of ovary (0.330±0.067 gm) and weight of egg (0.398±0.092 mg) was noticed to be in case of double treatment (IV and V instar larvae were treated) by th th 60% phytoecdysteroid and minimum was recorded in triple treatment (III , IV and V instar larvae were treated) rd th th by 70% phytoecdysteroid concentration. Phytoecdysteroid treatment, if applied tactfully, may be useful for boosting up the sericulture industry as well as the economy of silkworm rearing.