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1.
Chinese Journal of Natural Medicines (English Ed.) ; (6): 789-800, 2023.
Article Dans Anglais | WPRIM | ID: wpr-1010990

Résumé

Five new saponins, including three steroid saponins, paristenoids A-C (1-3), and two triterpenoid saponins, paristenoids D-E (4-5), along with four known ones (6-9) were isolated from the rhizomes of Paris polyphylla var. stenophylla. The structures of the isolated compounds were identified mainly by detailed spectroscopic analysis, including extensive 1D and 2D NMR, MS, as well as chemical methods. Compound 3 is a new cyclocholestanol-type steroidal saponin with a rare 6/6/6/5/5 fused-rings cholestanol skeleton, and this skeleton has been first found from the genus Paris. The cytotoxicities of the isolated compounds against three human three glioma cell lines (U87MG, U251MG and SHG44) were evaluated, and compound 7 displayed certain inhibitory effect with IC50 values of 15.22 ± 1.73, 18.87 ± 1.81 and 17.64 ± 1.69 μmol·L-1, respectively.


Sujets)
Humains , Rhizome/composition chimique , Stéroïdes/composition chimique , Liliaceae/composition chimique , Saponines/composition chimique , Triterpènes/analyse
2.
Pakistan Journal of Pharmaceutical Sciences. 2013; 26 (3): 623-628
Dans Anglais | IMEMR | ID: emr-142627

Résumé

Wild and tissue culture raised regenerants of Artemisia amygdalina, a critically endangered and endemic plant of Kashmir and North West Frontier Provinces of Pakistan were screened for the amount of bioactive principles and in particular antimalarial compound artemesinin. Phytochemical screening of extracts revealed the presence of terpenes, alkaloids, phenolics, tannins [polyphenolics], cardiac glycosides and steroids in wild [aerial, inflorescence] and tissue culture regenerants [in vitro grown plant, callus and green house acclimatized plants]. HPLC of Artemisia amygdalina revealed the presence of artemesinin in petroleum ether extracts of wild aerial part, tissue culture raised plant and green house acclimatized plants. Acetonitrile and water in 70:30 ratios at flow rate of 1ml/min was standardised as mobile phase. Retention time for standard chromatogram was 6.7. Wild inflorescences and callus does not produce artemesinin. This is the first report of phytochemical screening and artemesinin estimation of wild and tissue culture raised regenerants of Artemisia amygdalina


Sujets)
Facteurs biologiques/composition chimique , Glucosides cardiotoniques/composition chimique , Phénols/composition chimique , Extraits de plantes/composition chimique , Stéroïdes/composition chimique , Tanins/composition chimique , Terpènes/composition chimique , Techniques de culture de tissus/méthodes , Alcaloïdes/composition chimique , Antipaludiques
3.
Mem. Inst. Oswaldo Cruz ; 104(5): 683-688, Aug. 2009. ilus, graf, tab
Article Dans Anglais | LILACS | ID: lil-528073

Résumé

Steroids from Solanum nudum (SNs) have demonstrated antiplasmodial activity against erythrocytic stages of the Plasmodium falciparum strain FCB-2. It is well known that steroids can alter the membrane function of erythrocytes. Thus, we assessed alterations in the membranes of uninfected red blood cells, the parasite invasiveness and the solute-induced lysis of parasitised red blood cells (pRBCs). induced by SNs. We found that most merozoites were unable to invade SN-treated erythrocytes. However, transmission electron microscopy revealed no effect on the morphology of uninfected erythrocytes treated with either SN2 or diosgenone and neither SN induced haemolysis of uninfected erythrocytes. SN2 and SN4 inhibited isosmotic sorbitol and alanine-induced haemolysis of pRBCs. In contrast, diosgenone and SN1 did not inhibit solute-induced haemolysis. The inhibition of solute-induced lysis of parasitised erythrocytes by SN2 and SN4 suggest an action of these SNs on new permeability pathways of pRBCs.


Sujets)
Érythrocytes , Extraits de plantes/pharmacologie , Plasmodium falciparum/effets des médicaments et des substances chimiques , Solanum/composition chimique , Stéroïdes/pharmacologie , Membrane cellulaire/effets des médicaments et des substances chimiques , Membrane cellulaire/ultrastructure , Érythrocytes/effets des médicaments et des substances chimiques , Érythrocytes/parasitologie , Hémolyse/effets des médicaments et des substances chimiques , Microscopie électronique à transmission , Extraits de plantes/composition chimique , Plasmodium falciparum/ultrastructure , Stéroïdes/composition chimique , Stéroïdes/isolement et purification
4.
Indian J Exp Biol ; 2007 Jul; 45(7): 649-53
Article Dans Anglais | IMSEAR | ID: sea-61810

Résumé

Significant increase in polyamines levels in inflamed tissue was observed in the experimental animal models of inflammation. Treatment with dexamethasone positively modulated the levels of polyamines whereas non-steroidal drugs, diclofenac and valdecoxib negatively modulated their levels.


Sujets)
Animaux , Anti-inflammatoires/composition chimique , Anti-inflammatoires non stéroïdiens/pharmacologie , Carragénane/pharmacologie , Prolifération cellulaire , Inhibiteurs des cyclooxygénases/pharmacologie , Dexaméthasone/pharmacologie , Diclofenac/pharmacologie , Interactions médicamenteuses , Inflammation , Isoxazoles/composition chimique , Polyamines/composition chimique , Rats , Rat Wistar , Stéroïdes/composition chimique , Sulfonamides/composition chimique
5.
Mem. Inst. Oswaldo Cruz ; 100(7): 779-782, Nov. 2005. ilus, tab
Article Dans Anglais | LILACS | ID: lil-419706

Résumé

Complex physalin metabolites present in the capsules of the fruit of Physalis angulata L. have been isolated and submitted to a series of assays of antimicrobial activity against Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 29213, S. aureus ATCC 25923, S. aureus ATCC 6538P, Neisseria gonorrhoeae ATCC 49226, Escherichia coli ATCC 8739; E. coli ATCC 25922, Candida albicans ATCC 10231 applying different methodologies such as: bioautography, dilution broth, dilution agar, and agar diffusion techniques. A mixture of physalins (pool) containing physalins B, D, F, G inhibit S. aureus ATCC 29213, S. aureus ATCC 25923, S. aureus ATCC 6538P, and N. gonorrhoeae ATCC 49226 at a concentration of 200 mg/æl, using agar dilution assays. The mixture was inactive against P. aeruginosa ATCC27853, E. coli ATCC 8739; E. coli ATCC 25922, C. albicans ATCC 10231 when applying bioautography assays. Physalin B (200 æg/ml) by the agar diffusion assay inhibited S. aureus ATCC 6538P by n 85 percent; and may be considered responsible for the antimicrobial activity.


Sujets)
Antibactériens/pharmacologie , Candida albicans/effets des médicaments et des substances chimiques , Bactéries à Gram négatif/effets des médicaments et des substances chimiques , Bactéries à Gram positif/effets des médicaments et des substances chimiques , Lactones/composition chimique , Physalis/composition chimique , Stéroïdes/composition chimique , Agar-agar , Milieux de culture , Tests de sensibilité microbienne/méthodes , Extraits de plantes/pharmacologie
6.
Indian J Exp Biol ; 2004 Sep; 42(9): 893-9
Article Dans Anglais | IMSEAR | ID: sea-58109

Résumé

Rotula aquatica was extensively used by vaidyas (Ayurvedic practioners) in holistic treatment of cancer. In the present study, an attempt has been made to evaluate the antimitotic activity of R. aquatica. Preliminary antimitotic screening was done using Allium cepa root tip assay. The mitotic index of the root tips markedly decreased with increasing concentration of the aqueous extract. The different fractions obtained by successive extraction of R. aquatica using solvents of increasing polarity were also evaluated for their antimitotic activity. Tannins were isolated which showed a better activity than the non-tannin fraction. Experiments were also carried out with incorporation of folic acid in the aqueous extract. Folic acid inhibited the antimitotic activity of aqueous extract of R. aquatica in a dose dependent manner. The results obtained were compared with methotrexate--a known drug available in market as anti-cancer agent. The studies were extended to human cells using 3 pancreatic cancer cell lines, viz: HPAF-II, BxPC-3, and CAPAN-2. Extract of R. aquatica was found to be extremely effective in the prevention of cell proliferation of the pancreatic cancer cell lines. The phytochemical evaluation revealed presence of polyphenols (tannins) and steroids. A HPTLC fingerprinting was developed and studied. Two compounds were isolated and subjected to spectral studies like UV, IR and mass spectrums. The empirical formula was derived by considering this data with elemental analysis of the compounds.


Sujets)
Allium/composition chimique , Antimétabolites antinéoplasiques/pharmacologie , Boraginaceae/composition chimique , Division cellulaire/effets des médicaments et des substances chimiques , Chromatographie en phase liquide à haute performance , Acide folique/pharmacologie , Spectrométrie de masse , Méthotrexate/pharmacologie , Index mitotique , Tumeurs du pancréas/traitement médicamenteux , Phytothérapie , Extraits de plantes/usage thérapeutique , Racines de plante/cytologie , Stéroïdes/composition chimique , Tanins/métabolisme
7.
J Biosci ; 2001 Jun; 26(2): 253-63
Article Dans Anglais | IMSEAR | ID: sea-110671

Résumé

The study reveals that pre-ovulatory females of the fish Barilius bendelisis (Ham.) release sex steroids and their conjugates into the water and that a steroid sulphate of these compounds functions as a potent sex pheromone which stimulates milt production in conspecific males prior to spawning. Since males exposed to the purified subfraction III of the steroid sulphate fraction have increased milt volume and more spermatozoa with greater motility, the function of this priming pheromone appears to be to enhance male spawning success. High turbulence and faster water currents render the hillstream ecosystem extremely challenging for chemical communication. Therefore, ovulatory female fish secrete highly water soluble steroid sulphates for rapid pheromonal action in males. Inhibited milt volume in olfactory tract lesioned (OTL) males exposed to the steroid sulphate fraction and 17alpha,20 beta-dihydroxy-4-pregnen-3-one supports the concept that the pheromonally induced priming effect in male fish is mediated through olfactory pathways.


Sujets)
Animaux , Femelle , Poissons/physiologie , Mâle , Ovaire/composition chimique , Phéromones sexuelles/composition chimique , Comportement sexuel chez les animaux/physiologie , Odorat , Spermatozoïdes/physiologie , Stéroïdes/composition chimique , Température , Extraits tissulaires/composition chimique
8.
Rev. colomb. reumatol ; 7(3): 273-80, sept. 2000.
Article Dans Espagnol | LILACS | ID: lil-295742

Résumé

Se hace una revisión sobre los esteroides, invitando al médico general a olvidar el mito de que los esteroides son "veneno" y que solo son de uso privativo de los especialistas. La mayoría de errores que se comenten en la práctica diaria son por la ignorancia sobre el manejo de estos medicamentos que a través de la historia siguen demostrando ser armas importantísimas en el manejo de muchas patologías sobre todo en aquellas que son de origen "autoinmune".


Sujets)
Stéroïdes/composition chimique , Stéroïdes/pharmacocinétique , Stéroïdes/pharmacologie , Stéroïdes/usage thérapeutique
9.
Veterinary Medical Journal. 1996; 44 (4): 679-90
Dans Anglais | IMEMR | ID: emr-43700

Résumé

The study was done for deeper underst and ing of adverse effects concomitant with repeated administration of estrogens. It was found that, prolonged treatment, particularly with high doses, leads to deleterious effects represented by immunosuppresion, alteration of cellular structure of different organs as well as deviation of hepatorenal performance. Cautious use of estrogenic agents to avoid their drastic effect is recommended


Sujets)
Animaux de laboratoire , Femelle , Oestrogènes/administration et posologie , Stéroïdes/composition chimique , Avortement/étiologie
10.
J. bras. med ; 67(5/6): 19-41, nov.-dez. 1994. ilus, tab, graf
Article Dans Portugais | LILACS | ID: lil-164018

Résumé

A hiperplasia adrenal congênita (HAC) resulta de deficiência herdada em uma das várias enzimas necessárias para a síntese do cortisol. Deficiência na produçao de cortisol é comum a todas as formas de HAC, em decorrência da deficiência enzimática. Devido à existência de um mecanismo de feedback negativo entre a hipófise anterior e a supra-renal, ocorre aumento da secreçao de ACTH. Dependendo da severidade da deficicência enzimática, a concentraçao sérica de cortisol pode ou nao ser normalizada; porém sempre acompanhado de elevaçao dos esteróides precursores, resultando, nas formas clássicas de HAC, de alteraçoes bioquímicas e fenotípicas. O grau do bloqueio determina qual precursor estará elevado, enquanto que a severidade da deficiência enzimática determinará a extensao do comprometimento clínico. A forma nao-clássica da HAC diferencia-se da forma clássica pelo fato de os indivíduos afetados manifestarem sinais e sintomas de excesso androgênico tardiamente, ma infância ou adolescência, através de um espectro clínico variável, como pubarca precoce, acne, hirsutismo, distúrbio menstrual e infertilidade, podendo até mesmo nao manifestar sintomas, na chamada forma críptica da doença. O diagnóstico da forma nao-clássica de HAC, em geral, nao pode ser feito levando-se em consideraçao apenas a concentraçao basal dos hormônios esteróides, uma vez que estes podem se encontrar normais ou em concentraçao similar à das demais síndromes hiperandrogênicas. A dosagem dos hormônios esteróides após estímulo com ACTH sintético é o método que se impoe para o diagnóstico. Entretanto, os critérios diagnósticos ainda nao se encontram estabelecidos.


Sujets)
Humains , Mâle , Femelle , Hyperplasie congénitale des surrénales/diagnostic , Hormone corticotrope , Hormones/sang , Stéroïdes/sang , 3-Hydroxysteroid dehydrogenases/déficit , Diagnostic différentiel , Hyperandrogénie/diagnostic , Steroid 11-beta-hydroxylase/déficit , Steroid 21-hydroxylase/déficit , Stéroïdes/composition chimique
11.
Indian J Med Sci ; 1993 Apr; 47(4): 87-95
Article Dans Anglais | IMSEAR | ID: sea-66663

Résumé

Steroids produce anaesthesia besides producing the well known metabolic and hormonal effects. A number of anaesthetic steroids have been synthesized and tried clinically. Hydroxydione, althesin, minaxolone and pregnanolone are among those studied in detail. They act through GABAergic mechanism and are known to be advantageous over barbiturates.


Sujets)
Mélange alfaxalone alfadolone/composition chimique , Anesthésiques/composition chimique , Animaux , Prégnanediones/composition chimique , Prégnanolone/analogues et dérivés , Stéroïdes/composition chimique
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