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1.
Fitoterapia ; 134: 459-464, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30923008

RESUMO

In mice, poststerone is a major in vivo metabolite of the worldwide popular anabolic food supplement 20-hydroxyecdysone (20E). Here we present the first study on this ecdysteroid in view of the in vivo anabolic effect of its parent compound, 20E in mammals. We have monitored muscle fibre type cross sectional areas (CSA) of developing rats after treatment with poststerone as we did in a previous study with 20E. The muscle mass and fibre CSAs of soleus and EDL were increased by poststerone in a muscle specific manner as by 20E but there were some differences. Notably, the CSAs of type I and type IIa fibres in the soleus were less elevated by poststerone than by 20E. However poststerone increased the CSA of each four fibre types (I, IIa, IIx, IIb) in the EDL more effectively than 20E did. Poststerone, like 20E, also increased the number of myonuclei in the EDL of both hind limbs. Overall, this shows for the first time that poststerone having steroid nucleus and no side chain of 20E has a partly overlapping effect with that of 20E.


Assuntos
Ecdisterona/análogos & derivados , Ecdisterona/farmacologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Animais , Masculino , Estrutura Molecular , Ratos , Ratos Wistar
2.
J Mol Neurosci ; 67(2): 247-257, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30535775

RESUMO

Cell therapy and stem cell transplantation strategies have provided potential therapeutic approaches for the treatment of neurological disorders. Adipose-derived mesenchymal stem cells (ADMSCs) are abundant adult stem cells with low immunogenicity, which can be used for allogeneic cell replacement therapies. Differentiation of ADMSCs into acetylcholine-secreting motoneurons (MNs) is a promising treatment for MN diseases, such as spinal muscular atrophy (SMA), which is associated with the level of SMN1 gene expression. The SMN2 gene plays an important role in MN disorders, as it can somewhat compensate for the lack of SMN1 expression in SMA patients. Although the differentiation potential of ADMSCs into MNs has been previously established, overexpression of SMN2 gene in a shorter period with a longer survival has yet to be elucidated. Ponasterone A (PNA), an ecdysteroid hormone activating the PI3K/Akt pathway, was studied as a new steroid to promote SMN2 overexpression in MNs differentiated from ADMSCs. After induction with retinoic acid, sonic hedgehog, forskolin, and PNA, MN phenotypes were differentiated from ADMSCs, and immunochemical staining, specific for ß-tubulin, neuron-specific enolase, and choline acetyltransferase, was performed. Also, the results of real-time PCR assay indicated nestin, Pax6, Nkx2.2, Hb9, Olig2, and SMN2 expression in the differentiated cells. After 2 weeks of treatment, cultures supplemented with PNA showed a longer survival and a 1.2-fold increase in the expression of SMN2 (an overall 5.6-fold increase; *P ≤ 0.05), as confirmed by the Western blot analysis. The PNA treatment increased the levels of ChAT, Isl1, Hb9, and Nkx2 expression in MN-like cells. Our findings highlight the role of PNA in the upregulation of SMN2 genes from MSC-derived MN-like cells, which may serve as a potential candidate in cellular therapy for SMA patients.


Assuntos
Adipócitos/metabolismo , Ecdisterona/análogos & derivados , Células-Tronco Mesenquimais/metabolismo , Neurônios Motores/metabolismo , Neurogênese , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adolescente , Adulto , Idoso , Células Cultivadas , Ecdisterona/farmacologia , Proteína Homeobox Nkx-2.2 , Proteínas de Homeodomínio , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Pessoa de Meia-Idade , Neurônios Motores/citologia , Proteínas Nucleares , Proteína 2 de Sobrevivência do Neurônio Motor/genética , Proteína 2 de Sobrevivência do Neurônio Motor/metabolismo , Fatores de Transcrição , Regulação para Cima
3.
PLoS Negl Trop Dis ; 10(6): e0004772, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27300294

RESUMO

BACKGROUND: A homologue of the ecdysone receptor has previously been identified in human filarial parasites. As the ecdysone receptor is not found in vertebrates, it and the regulatory pathways it controls represent attractive potential chemotherapeutic targets. METHODOLOGY/ PRINCIPAL FINDINGS: Administration of 20-hydroxyecdysone to gerbils infected with B. malayi infective larvae disrupted their development to adult stage parasites. A stable mammalian cell line was created incorporating the B. malayi ecdysone receptor ligand-binding domain, its heterodimer partner and a secreted luciferase reporter in HEK293 cells. This was employed to screen a series of ecdysone agonist, identifying seven agonists active at sub-micromolar concentrations. A B. malayi ecdysone receptor ligand-binding domain was developed and used to study the ligand-receptor interactions of these agonists. An excellent correlation between the virtual screening results and the screening assay was observed. Based on both of these approaches, steroidal ecdysone agonists and the diacylhydrazine family of compounds were identified as a fruitful source of potential receptor agonists. In further confirmation of the modeling and screening results, Ponasterone A and Muristerone A, two compounds predicted to be strong ecdysone agonists stimulated expulsion of microfilaria and immature stages from adult parasites. CONCLUSIONS: The studies validate the potential of the B. malayi ecdysone receptor as a drug target and provide a means to rapidly evaluate compounds for development of a new class of drugs against the human filarial parasites.


Assuntos
Ecdisona/metabolismo , Ecdisterona/análogos & derivados , Filariose/tratamento farmacológico , Hidrazinas/farmacologia , Receptores de Esteroides/agonistas , Diamino Aminoácidos/administração & dosagem , Animais , Brugia Malayi/efeitos dos fármacos , Brugia Malayi/isolamento & purificação , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Ecdisterona/química , Ecdisterona/farmacologia , Filariose/parasitologia , Gerbillinae , Células HEK293 , Humanos , Hidrazinas/química , Hidrazinas/isolamento & purificação , Larva/efeitos dos fármacos , Ligantes , Modelos Moleculares , Simulação de Acoplamento Molecular , Receptores de Esteroides/metabolismo
4.
Phytochem Anal ; 26(5): 293-300, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25953625

RESUMO

INTRODUCTION: Ajuga turkestanica is a plant used in traditional medicine for its high ecdysteroid content, including the presence of the particularly active turkesterone, which possess efficient anabolic activity. OBJECTIVES: To isolate and identify minor ecdysteroids present in a semi-purified plant fraction containing ca. 70% turkesterone. MATERIAL AND METHODS: Multi-step preparative HPLC (combining RP- and NP-HPLC systems) was used to purify the different components present in the turkesterone fraction. Isolated compounds were identified by high-resolution mass spectrometry and 2D-NMR. RESULTS: Fourteen ecdysteroids (including turkesterone and 20-hydroxyecdysone) were isolated. Seven of these, all bearing an 11α-hydroxy group, were previously unreported. CONCLUSION: Ajuga turkestanica ecdysteroids are characterised by the abundance of 11α-hydroxylated compounds and by the simultaneous presence of 24C, 27C, 28C and 29C ecdysteroids. It is expected that even more ecdysteroids are to be found in this plant since the starting material for this study lacked the less polar ecdysteroids. The simultaneous presence of 20-hydroxyecdysone and turkesterone (its 11α-hydroxy analogue) as the two major ecdysteroids suggests that every ecdysteroid is probably present in both 11α-hydroxy and 11-deoxy forms.


Assuntos
Ajuga/química , Ecdisteroides/análise , Raízes de Plantas/química , Plantas Medicinais/química , Cromatografia Líquida de Alta Pressão/métodos , Ecdisteroides/química , Ecdisteroides/isolamento & purificação , Ecdisterona/análogos & derivados , Ecdisterona/análise , Ecdisterona/química , Ecdisterona/isolamento & purificação , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos
5.
Bioorg Med Chem Lett ; 25(8): 1665-1670, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25813159

RESUMO

The phytochemical investigation of a Tunisian plant Atriplex portulacoides (Chenopodiaceae) led to the isolation of two new compounds designated as portulasoid (2) and septanoecdysone (3) along with the known 20-hydroxyecdysone (20HE) (1). Their chemical structures were elucidated on the basis of extensive spectroscopic methods including ES-HRMS, 1D and 2D-NMR. The isolated compounds were finally tested for their antioxidant activity by using DPPH, ABTS(+), Fe(3+) and catalase assays and also for their antibacterial and anticholinesterase activities.


Assuntos
Atriplex/química , Ecdisterona/análogos & derivados , Ecdisterona/química , Antioxidantes/química , Atriplex/metabolismo , Colinesterases/química , Colinesterases/metabolismo , Ecdisterona/metabolismo , Ecdisterona/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Conformação Molecular , Extratos Vegetais/química , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Ligação Proteica
6.
Phytomedicine ; 21(6): 787-92, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24680617

RESUMO

Tetra-acetylajugasterone C (TAAC) was found to be one of the naturally occurring compounds of the Cameroonian medicinal plant Vitex cienkowskii which is responsible for a vasorelaxant activity of an extract of this plant. The evaluation of the underlying mechanisms for the relaxing effect of TAAC was determined using aortic rings of rats and mice. TAAC produced a concentration-dependent relaxation in rat artery rings pre-contracted with 1µM noradrenaline (IC50: 8.40µM) or 60mM KCl (IC50: 36.30µM). The nitric oxide synthase inhibitor l-NAME (100µM) and the soluble guanylate cyclase inhibitor ODQ (10µM) significantly attenuated the vasodilatory effect of TAAC. TAAC also exerted a relaxing effect in aorta of wild-type mice (cGKI(+/+); IC50=13.04µM) but a weaker effect in aorta of mice lacking cGMP-dependent protein kinase I (cGKI(-/-); IC50=36.12µM). The involvement of calcium channels was studied in rings pre-incubated in calcium-free buffer and primed with 1µM noradrenaline prior to addition of calcium to elicit contraction. TAAC (100µM) completely inhibited the resulting calcium-induced vasoconstriction. The same concentration of TAAC showed a stronger effect on the tonic than on the phasic component of noradrenaline-induced contraction. This study shows that TAAC, a newly detected constituent of Vitex cienkowskii contributes to the relaxing effect of an extract of the plant. The effect is partially mediated by the involvement of the NO/cGMP pathway of the smooth muscle but additionally inhibition of calcium influx into the cell may play a role.


Assuntos
Ecdisterona/análogos & derivados , Endotélio Vascular/efeitos dos fármacos , Extratos Vegetais/farmacologia , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Vitex/química , Animais , Aorta/efeitos dos fármacos , Cálcio/metabolismo , Canais de Cálcio/metabolismo , GMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Ecdisterona/isolamento & purificação , Ecdisterona/farmacologia , Endotélio Vascular/metabolismo , Inibidores Enzimáticos/farmacologia , Guanilato Ciclase/antagonistas & inibidores , Camundongos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Norepinefrina/farmacologia , Casca de Planta , Extratos Vegetais/química , Caules de Planta , Ratos , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Guanilil Ciclase Solúvel , Vasodilatadores/isolamento & purificação
7.
ScientificWorldJournal ; 2012: 651275, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22645442

RESUMO

Two new and one known ecdysteroids were identified in the methanolic extract of the roots of Serratula wolffii. The new compounds isolated were ponasterone A-22-apioside (1) and 3-epi-shidasterone (3), together with the known 3-epi-22-deoxy-20-hydroxyecdysone (2). The structures of compounds 1-3 were determined by extensive spectroscopic techniques, including one- and two-dimensional NMR methods.


Assuntos
Asteraceae/metabolismo , Ecdisteroides/química , Química Farmacêutica/métodos , Desenho de Fármacos , Ecdisterona/análogos & derivados , Ecdisterona/química , Glicosídeos/química , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Modelos Químicos , Extratos Vegetais/farmacologia , Raízes de Plantas/metabolismo , Espectrofotometria/métodos
8.
Gen Comp Endocrinol ; 173(2): 346-55, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21722641

RESUMO

In arthropods, ecdysteroids regulate molting by activating a heterodimer formed by the ecdysone receptor (EcR) and retinoid X receptor (RXR). While this mechanism is similar in insects and crustaceans, variation in receptor splicing, dimerization and ligand affinity adds specificity to molting processes. This study reports the EcR and RXR sequences from American lobster, a commercially and ecologically important crustacean. We cloned two EcR splice variants, both of which specifically bind ponasterone A, and two RXR variants, both of which enhance binding of ponasterone A to the EcR. Lobster EcR has high affinity for ponasterone A and muristerone and moderately high affinity for the insecticide tebufenozide. Bisphenol A, diethyl phthalate, and two polychlorinated biphenyls (PCB 29 and PCB 30), environmental chemicals shown to interfere with crustacean molting, showed little or no affinity for lobster EcR. These studies establish the molecular basis for investigation of lobster ecdysteroid signaling and signal disruption by environmental chemicals.


Assuntos
Nephropidae/metabolismo , Receptores de Esteroides/metabolismo , Animais , Ecdisterona/análogos & derivados , Ecdisterona/metabolismo , Hidrazinas/metabolismo , Ácidos Ftálicos/metabolismo , Bifenilos Policlorados/metabolismo , Isoformas de Proteínas/metabolismo
9.
J Chem Inf Model ; 51(2): 296-305, 2011 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21275397

RESUMO

Insect growth is regulated by the orchestrated event of ecdysteroids and their receptor proteins. Agonists/antagonists of ecdysteroid receptor are predicted to disrupt normal growth, providing good candidates of new insecticides. A database of over 2 million compounds was subjected to a shape-based virtual screening cascade to identify novel nonsteroidal hits similar to the known EcR ligand ponasterone A. Testing revealed micromolar hits against two strains of insect cells. Docking experiments against EcR were used to support the predicted binding mode of these ligands based on their overlay to ponasterone A.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Proteínas de Insetos/metabolismo , Receptores de Esteroides/metabolismo , Interface Usuário-Computador , Sequência de Aminoácidos , Animais , Linhagem Celular , Biologia Computacional , Bases de Dados Factuais , Drosophila melanogaster/genética , Desenho de Fármacos , Ecdisona/agonistas , Ecdisona/metabolismo , Ecdisterona/análogos & derivados , Ecdisterona/química , Ecdisterona/metabolismo , Ecdisterona/farmacologia , Genes Reporter/genética , Proteínas de Choque Térmico HSP27/genética , Proteínas de Insetos/química , Ligantes , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Receptores de Esteroides/química , Reprodutibilidade dos Testes , Spodoptera
10.
Phytochemistry ; 71(8-9): 975-81, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20347104

RESUMO

Phytoecdysteroid glucosides, brainesterosides A-E, were isolated from the rhizomes of Brainea insignis along with three known phytoecdysteroids, ponasteroside A, ponasterone A, and 20-hydroxyecdysone. Their structures were elucidated by spectroscopic and chemical means. A possible biogenetic pathway is postulated for these compounds. The chemosystematic significance of ponasterone A is discussed.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Ecdisterona/análogos & derivados , Glucosídeos/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Ecdisterona/química , Ecdisterona/isolamento & purificação , Glucosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Rizoma/química
11.
Zhong Yao Cai ; 33(10): 1574-6, 2010 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-21355194

RESUMO

OBJECTIVE: To study the chemical constituents from the roots of Tinospora sagittata var. yunnanensis. METHODS: Various chromatographic techniques were used to isolate and purify the constituents. The structures of these compounds were elucidated on the basis of spectral analysis. RESULTS: Seven compounds were isolated from the plant and their structures were identified as tinophylloloside (1), epitinophylloloside (2), 2-deoxycrustecdysone (3), polypodine B (4) , (+)-5'-methoxyisolariciresinol 3alpha-O-beta-D-glucopyranoside (5), geniposide (6), adenine (7). CONCLUSION: All compounds are isolated from the plant for the first time,and compounds 4, 5, 6 and 7 are isolated firstly from the genus.


Assuntos
Adenina/isolamento & purificação , Ecdisterona/análogos & derivados , Iridoides/isolamento & purificação , Raízes de Plantas/química , Tinospora/química , Adenina/química , Ecdisterona/química , Ecdisterona/isolamento & purificação , Iridoides/química , Espectroscopia de Ressonância Magnética , Plantas Medicinais/química , Plantas Medicinais/crescimento & desenvolvimento , Tinospora/crescimento & desenvolvimento
12.
Phytochem Anal ; 20(1): 58-63, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19086092

RESUMO

INTRODUCTION: The genus Asparagus is known to contain phytoecdysteroids that have been shown to exhibit many beneficial pharmacological properties such as improving lipid metabolism, modulating immunological responses, etc. Currently, knowledge about the contents of phytoecdysteroids in the roots of Asparagus species is limited and HPLC methods for their analyses are unsatisfactory. OBJECTIVE: To develop an HPLC method for the simultaneous determination of three phytoecdysteroids, 20-hydroxyecdysone, ecdysone and ajugasterone C, in the roots of four Asparagus species. METHODOLOGY: Reference standards of phytoecdysteroids were isolated from the roots of Asparagus filicinus by open column chromatography. HPLC analysis was performed on an Alltima C(18) column with gradient elution using aqueous 0.2% formic acid solution containing 0.2% isopropanol and acetonitrile. RESULTS: All calibration curves showed good linear correlation coefficients (r(2) > 0.9994) within the tested ranges. Limits of detection (S/N = 3) and quantification (S/N = 10) for the three analytes were less than 2.7 and 9.9 ng, respectively. Intra- and inter-day RSDs of retention times and peak areas were less than 2.61%. The recoveries were between 93.2 and 107.5%, and the RSDs were less than 3.83% for the root samples of A. filicinus. CONCLUSION: The HPLC method established is appropriate for the efficient quantitative and qualitative analyses of important phytoecdysteroids in Asparagus species. This study showed that A. filicinus is rich in phytoecdysteroids, especially 20-hydroxyecdysone. However the three studied phytoecdysteroids were not detected in A. cochinchinensis, A. officinalis and A. setaceus.


Assuntos
Asparagus/química , Ecdisteroides/química , Calibragem , Cromatografia Líquida de Alta Pressão , Ecdisona/química , Ecdisona/isolamento & purificação , Ecdisterona/análogos & derivados , Ecdisterona/química , Ecdisterona/isolamento & purificação , Raízes de Plantas/química , Plantas Medicinais/química , Padrões de Referência , Reprodutibilidade dos Testes , Solventes , Especificidade da Espécie , Espectrofotometria Ultravioleta
13.
Zhongguo Zhong Yao Za Zhi ; 32(14): 1421-5, 2007 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17966356

RESUMO

OBJECTIVE: To study the non-taxoids in the leaves of Taxus mairei. METHOD: The chemical constituents were isolated by chromatography and identified by spectral data. RESULT: Five compounds, taxamairin A (1), taxamairin B (2), sciadopitysin (3), ( - ) matairesinol (4), ponasterone A (5) were isolated and identified. CONCLUSION: Compounds 3-5 were isolated from this plant for the first time, compounds 1 and 2 were isolated from the leaves of T. mairei for the first time.


Assuntos
Biflavonoides/isolamento & purificação , Ecdisterona/análogos & derivados , Furanos/isolamento & purificação , Lignanas/isolamento & purificação , Plantas Medicinais/química , Taxus/química , Biflavonoides/química , Diterpenos/química , Diterpenos/isolamento & purificação , Ecdisterona/química , Ecdisterona/isolamento & purificação , Furanos/química , Lignanas/química , Folhas de Planta/química
14.
Steroids ; 72(3): 270-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17210166

RESUMO

An extract from aerial parts of Ajuga nipponensis Makino was examined by high performance liquid chromatography for minor ecdysteroids. Along with the compounds already reported, namely cyasterone, ajugasterone C, cyasterone 22-acetate and 22-dehydrocyasterone, the presence of three additional bands with the expected ecdysteroid-like UV absorption was observed. The structures of the isolates were unambiguously elucidated based on extensive NMR spectral studies (one and two-dimensional experiments) and pointed out three new phytoecdysteroids. One of the new compounds, 22-dehydrocyasterone 2-glucoside is just the second example of a C-2 glucosyl derivative. The other two compounds displayed hemiacetal functions in the side chain, one unprecedented, and were named ajugacetalsterone A and B.


Assuntos
Ajuga/química , Ecdisteroides/química , Ecdisteroides/isolamento & purificação , Plantas Medicinais/química , Cromatografia Líquida de Alta Pressão/métodos , Ecdisterona/análogos & derivados , Ecdisterona/análise , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química
15.
Zhongguo Zhong Yao Za Zhi ; 30(4): 272-4, 2005 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15724404

RESUMO

OBJECTIVE: To study the chemical constituents from Lamium maculatum var. kansuense. METHOD: The chemical constituents were isolated and repeatedly purified on silica gel column and the structures were elucidated by the NMR spectra and physico-chemical properties. RESULT: Six compounds were obtained and identified as polypodine B (I), 5-OH-8-epiloganin (II), shlanzhiside methyl ester (III), liriodendrin (IV), quercitroside (V), uridine (VI). CONCLUSION: Compound IV was found from genus Lamium for the first time and the rest of the compounds were found from Lamium maculatum var kansuense for the first time.


Assuntos
Ecdisterona/análogos & derivados , Ecdisterona/isolamento & purificação , Furanos/isolamento & purificação , Glucosídeos/isolamento & purificação , Lamiaceae/química , Plantas Medicinais/química , Ecdisterona/química , Furanos/química , Glucosídeos/química , Uridina/química , Uridina/isolamento & purificação
16.
Yao Xue Xue Bao ; 38(10): 760-2, 2003 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-14730899

RESUMO

AIM: To investigate the chemical constituents of Cyanotis arachnoidea. METHODS: By using chromatographic methods for separation and combination with spectral analysis, their chemical structures were determined. RESULTS: Six compounds were identified as ajugasterone C-20, 22-acetonide (1), 20-hydroxyecdysone-20, 22-acetonide (2), 22-oxo-ajugasterone C (3), 22-oxo-20-hydroxyecdysone (4), beta-sitosterol (5), daucosterol (6). CONCLUSION: Compound 3 is a new compound, 4 was a new natural compound.


Assuntos
Commelinaceae/química , Ecdisona/isolamento & purificação , Ecdisterona/isolamento & purificação , Plantas Medicinais/química , Ecdisona/análogos & derivados , Ecdisona/química , Ecdisterona/análogos & derivados , Ecdisterona/química , Estrutura Molecular , Sitosteroides/química , Sitosteroides/isolamento & purificação
17.
J Biol Chem ; 277(24): 21474-9, 2002 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-11937499

RESUMO

The calpains, a family of calcium-requiring intracellular proteases, are proposed regulators of cell proliferation. However, ablation of the calpain small subunit gene necessary for function of the conventional calpains did not result in decreased rate of proliferative growth of mouse stem cells under routine culture conditions. To address the reasons for this discrepancy, Chinese hamster ovary cell lines were established that overexpress the calpain inhibitor protein, calpastatin, under control of the ecdysone congener, ponasterone A. Overexpression of calpastatin in these cell lines resulted in a decreased growth of isolated colonies adhering to tissue culture plates. However, when cells were plated at higher density, calpastatin overexpression had no influence on proliferative growth rate. Growth of colonies in soft agar was not inhibited by calpastatin overexpression. Cell adhesion, cell de-adhesion, and cell motility all appeared to be normal after calpastatin overexpression. Differential display analysis was initiated to detect possible alteration of gene expression upon calpastatin overexpression. Analysis of approximately 3000 differential display PCR signals resulted in identification of one band that was underexpressed. Northern blot analysis confirmed a decreased amount of approximately 1 kb mRNA in cells overexpressing calpastatin. Sequence analysis identified a putative protein, Csr, containing a region homologous to two ubiquitin transferases and a putative cation channel protein.


Assuntos
Proteínas de Ligação ao Cálcio/biossíntese , Calpaína/antagonistas & inibidores , Divisão Celular/efeitos dos fármacos , Ecdisterona/análogos & derivados , Sequência de Aminoácidos , Animais , Northern Blotting , Western Blotting , Células CHO , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Cátions , Adesão Celular , Movimento Celular , Cricetinae , DNA Complementar/metabolismo , Relação Dose-Resposta a Droga , Regulação para Baixo , Ecdisterona/metabolismo , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Humanos , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos , Fatores de Tempo , Transfecção , Tripsina/farmacologia
18.
Insect Biochem Mol Biol ; 32(2): 161-5, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11755058

RESUMO

Seven phytoecdysteroids have been isolated from Serratula coronata L. One of them is a new phytoecdysteroid, 3-epi-20-hydroxyecdysone. Two further ecdysteroids, 20-hydroxyecdysone 22-acetate and taxisterone, are isolated from this species for the first time in addition to the typical S. coronata ecdysteroids, 20-hydroxyecdysone, ecdysone, ajugasterone C and polypodine B. The juice squeezed from aerial parts of fresh plants of S. coronata was extracted with ethyl acetate. The ecdysteroids were isolated by a combination of chromatographic techniques (mainly HPLC) and identified by 1D and 2D (1)H and (13)C NMR experiments and mass-spectrometry. The biological activities of 3-epi-20-hydroxyecdysone (EC(50)=1.6 x 10(-7) M), taxisterone (EC(50)=9.5 x 10(-8) M) and ajugasterone C (EC(50)=6.2 x 10(-8) M) have been determined in the Drosophila melanogaster B(II) bioassay for ecdysteroid agonist activity.


Assuntos
Asteraceae/química , Ecdisterona/análise , Ecdisterona/análogos & derivados , Extratos Vegetais/química , Espectrofotometria Infravermelho/métodos , Espectrofotometria Ultravioleta/métodos
19.
Eksp Klin Farmakol ; 64(4): 56-8, 2001.
Artigo em Russo | MEDLINE | ID: mdl-11589113

RESUMO

Phytoecdysteroids ecdysteron and turkesteron isolated from Ajuga turkestanica (Rgl.) Brig. decrease the manifestations of uremic intoxication in rats with experimental renal pathology induced by a nephrotoxic mixture (containing uranyl acetate and glycerol). Injected in a dose of 5 mg/kg, the drugs restore glomerular filtration level, favor the disappearance of the albuminuria and normalize urinary sediments. The nephroprotector effect of the phytoecdysteroids studied resembles the action of a steroidal anabolic drug nerobol.


Assuntos
Ecdisterona/análogos & derivados , Ecdisterona/uso terapêutico , Nefropatias/tratamento farmacológico , Metandrostenolona/uso terapêutico , Fitoterapia , Animais , Diurese , Ecdisterona/farmacologia , Glicerol , Nefropatias/induzido quimicamente , Nefropatias/fisiopatologia , Masculino , Metandrostenolona/farmacologia , Compostos Organometálicos , Proteinúria/tratamento farmacológico , Proteinúria/urina , Ratos
20.
Exp Cell Res ; 253(2): 474-82, 1999 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-10585270

RESUMO

Human 293 cells were stably transfected with a plasmid introducing a receptor for the ecdysone analog muristerone. The cells were further stably transfected with muristerone-inducible expression vectors carrying either the cDNA for the human high K(M) 5'-nucleotidase or the coding sequence of the nucleotidase linked to the 5'-end of the sequence for the green fluorescent protein. Upon induction, both types of transfectants overproduced nucleotidase activity in a time- and dose-dependent manner. Western blots gave values close to the expected subunit molecular masses of 65 and 92 kDa, respectively, excluding processing of the induced proteins. Cells induced to overexpress the nucleotidase showed a decreased growth rate and contained smaller pools of each of the four common ribonucleoside triphosphates. They showed no increased resistance to the toxicity of 2-chlorodeoxyadenosine.


Assuntos
5'-Nucleotidase/genética , Regulação Enzimológica da Expressão Gênica/fisiologia , 5'-Nucleotidase/análise , 5'-Nucleotidase/metabolismo , Trifosfato de Adenosina/análise , Trifosfato de Adenosina/metabolismo , Antineoplásicos/farmacologia , Western Blotting , Células Cultivadas , Cladribina/farmacologia , Clonagem Molecular , Citidina Trifosfato/análise , Citidina Trifosfato/metabolismo , DNA Complementar , Ecdisterona/análogos & derivados , Ecdisterona/farmacologia , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Proteínas de Fluorescência Verde , Guanosina Trifosfato/análise , Guanosina Trifosfato/metabolismo , Humanos , Indicadores e Reagentes/metabolismo , Rim/citologia , Proteínas Luminescentes/genética , Plasmídeos , Receptores de Esteroides/genética , Transfecção , Uridina Trifosfato/análise , Uridina Trifosfato/metabolismo
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