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1.
J Nat Prod ; 86(4): 1074-1080, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-36825873

RESUMO

Ecdysteroid-containing herbal extracts, commonly prepared from the roots of Cyanotis arachnoidea, are marketed worldwide as a "green" anabolic food supplement. Herein are reported the isolation and complete 1H and 13C NMR signal assignments of three new minor ecdysteroids (compounds 2-4) from this extract. Compound 4 was identified as a possible artifact that gradually forms through the autoxidation of calonysterone. The compounds tested demonstrated a significant protective effect on the blood-brain barrier endothelial cells against oxidative stress or inflammation at a concentration of 1 µM. Based on these results, minor ecdysteroids present in food supplements may offer health benefits in various neurodegenerative disease states.


Assuntos
Commelinaceae , Doenças Neurodegenerativas , Humanos , Ecdisteroides/farmacologia , Ecdisteroides/química , Barreira Hematoencefálica , Células Endoteliais , Commelinaceae/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química
2.
Artigo em Inglês | MEDLINE | ID: mdl-36048499

RESUMO

We have previously published six esterified O-acyl (EFB1) and three N-acyl fumonisin B1 derivatives extracted from rice cultures inoculated with Fusarium verticillioides, amongst these the identification of N-palmitoyl-FB1 has been clearly established in a spiking experiment. At that time, it was assumed that as in the case of O-acyl-FB1 derivatives, linoleic-, oleic- or palmitic acid esterify through the OH group on the 3C or 5C atom of the carbon chain of the fumonisins. In our most recent experiments, we have synthetically acylated the FB1 toxin and subsequently purified 3-O-palmitoyl- and 5-O-palmitoyl-FB1 toxins in addition to the N-palmitoyl-FB1 toxin. They were identified and characterised using 1H and 13C NMR as well as LC-HRMS. Our aim was the identification of the previously detected O-acyl-FB1 derivatives over the course of a spiking experiment, which were obtained through the solid-phase fermentation of Fusarium verticillioides. By spiking the three synthesized and identified components one-by-one into the fungal culture extract and analysing these cultures using LC-MS, it was clearly demonstrated that the F. verticillioides strain produced both the 5-O-palmitoyl-FB1 and N-palmitoyl-FB1 toxins, but did not produce 3-O-palmitoyl-FB1. Thus, it is highly probable that the components thought to be 3-O-acyl-(linoleoyl-, oleoyl-, palmitoyl-) FB1 derivatives in our previous communication are presumably 10-O-acyl-FB1 derivatives. Since these acylated FB1 derivatives can occur naturally in e.g. maize, the use of these synthesized components as reference materials is of great importance in order to obtain accurate qualitative and quantitative data on the occurrence of acylated fumonisins in different matrices including maize based feed samples. The production of these substances has also made it possible to test their toxicity in cell culture and small animal experiments.


Assuntos
Fumonisinas , Fusarium , Animais , Carbono , Fumonisinas/análise , Fusarium/química , Ácido Palmítico/química , Extratos Vegetais
3.
J Nat Prod ; 84(7): 1870-1881, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34143640

RESUMO

Ecdysteroids act as molting hormones in insects and as nonhormonal anabolic agents and adaptogens in mammals. A wide range of ecdysteroid-containing herbal extracts are available worldwide as food supplements. The aim of this work was to study such an extract as a possible industrial source of new bioactive ecdysteroids. A large-scale chromatographic isolation was performed from an extract of Cyanotis arachnoidea roots. Ten ecdysteroids (1-10) including eight new compounds were isolated and characterized by extensive nuclear magnetic resonance studies. Highly unusual structures were identified, including a H-14ß (1, 2, 4, and 10) moiety, among which a 14ß(H)17ß(H) phytosteroid (1) is reported for the first time. Compounds with an intact side chain (4-10) and 11 other natural or semisynthetic ecdysteroids (11-21) were tested for insect ecdysteroid receptor (EcR) binding activity. Two new compounds, i.e., 14-deoxydacryhainansterone (5) and 22-oxodacryhainansterone (6), showed strong EcR binding activity (IC50 = 41.7 and 380 nM, respectively). Six compounds were identified as EcR agonists and another two as antagonists using a transgenic ecdysteroid reporter gene assay. The present results demonstrate that commercial C. arachnoidea extracts are rich in new, unusual bioactive ecdysteroids. Because of the lack of an authentic plant material, the truly biosynthetic or artifactual nature of these compounds cannot be confirmed.


Assuntos
Commelinaceae/química , Ecdisteroides/química , Fitosteróis/química , Extratos Vegetais/química , Receptores de Esteroides/metabolismo , Animais , Estrutura Molecular , Raízes de Plantas/química , Células Sf9
4.
Int J Mol Sci ; 22(2)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466640

RESUMO

Candida auris is a potential multidrug-resistant pathogen able to persist on indwelling devices as a biofilm, which serve as a source of catheter-associated infections. Neosartorya fischeri antifungal protein 2 (NFAP2) is a cysteine-rich, cationic protein with potent anti-Candida activity. We studied the in vitro activity of NFAP2 alone and in combination with fluconazole, amphotericin B, anidulafungin, caspofungin, and micafungin against C. auris biofilms. The nature of interactions was assessed utilizing the fractional inhibitory concentration index (FICI), a Bliss independence model, and LIVE/DEAD viability assay. NFAP2 exerted synergy with all tested antifungals with FICIs ranging between 0.312-0.5, 0.155-0.5, 0.037-0.375, 0.064-0.375, and 0.064-0.375 for fluconazole, amphotericin B, anidulafungin, caspofungin, and micafungin, respectively. These results were confirmed using a Bliss model, where NFAP2 produced 17.54 µM2%, 2.16 µM2%, 33.31 µM2%, 10.72 µM2%, and 111.19 µM2% cumulative synergy log volume in combination with fluconazole, amphotericin B, anidulafungin, caspofungin, and micafungin, respectively. In addition, biofilms exposed to echinocandins (32 mg/L) showed significant cell death in the presence of NFAP2 (128 mg/L). Our study shows that NFAP2 displays strong potential as a novel antifungal compound in alternative therapies to combat C. auris biofilms.


Assuntos
Antifúngicos/metabolismo , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Proteínas Fúngicas/metabolismo , Neosartorya/metabolismo , Antifúngicos/farmacologia , Candida/fisiologia , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Sinergismo Farmacológico , Proteínas Fúngicas/farmacologia , Humanos
5.
Thromb Haemost ; 120(11): 1548-1556, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32772348

RESUMO

BACKGROUND: For patients treated with dual antiplatelet therapy, standardized drug-specific 3-to-7 day cessation is recommended prior to major surgery to reach sufficient platelet function recovery. Here we investigated the hypothesis that supplemental fibrinogen might mitigate the inhibitory effects of antiplatelet therapy. METHODS AND RESULTS: To this end blood from healthy donors was treated in vitro with platelet inhibitors, and in vitro thrombus formation and platelet activation were assessed. Ticagrelor, acetylsalicylic acid, the combination of both, and tirofiban all markedly attenuated the formation of adherent thrombi, when whole blood was perfused through collagen-coated microchannels at physiological shear rates. Addition of fibrinogen restored in vitro thrombus formation in the presence of antiplatelet drugs and heparin. However, platelet activation, as investigated in assays of P-selectin expression and calcium flux, was not altered by fibrinogen supplementation. Most importantly, fibrinogen was able to restore in vitro thrombogenesis in patients on maintenance dual antiplatelet therapy after percutaneous coronary intervention. CONCLUSION: Thus, our in vitro data support the notion that supplementation of fibrinogen influences the perioperative hemostasis in patients undergoing surgery during antiplatelet therapy by promoting thrombogenesis without significantly interfering with platelet activation.


Assuntos
Fibrinogênio/farmacologia , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Trombose/prevenção & controle , Idoso , Aspirina/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Feminino , Hemorreologia , Heparina/farmacologia , Hirudinas/farmacologia , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Selectina-P/biossíntese , Selectina-P/genética , Ticagrelor/farmacologia , Tirofibana/farmacologia
6.
J Chromatogr A ; 1611: 460574, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31591039

RESUMO

Sixteen pairs of enantiomeric dipeptides were separated on four chiral ion-exchanger-type stationary phases based on Cinchona alkaloids. Anion-exchangers (QN-AX, QD-AX) and zwitterionic phases [ZWIX(+)™ and ZWIX(-)™] were studied in a comparative manner. The effects of the nature and concentrations of the mobile phase solvent components and organic salt additives on analyte retention and enantioseparation were systematically studied in order to get a deeper insight into the enantiorecognition mechanism. Moreover, experiments were performed in the temperature range 10-50 °C to calculate thermodynamic parameters like changes in standard enthalpy, Δ(ΔH°), entropy, Δ(ΔS°), and free energy, Δ(ΔG°) on the basis of van't Hoff plots derived from the ln α vs. 1/T curves. Elution sequences of the dipeptides were determined in all cases and, with a few exceptions, they were found to be opposite on the pseudoenantiomeric stationary phases as of QN-AX/QD-AX and of ZWIX(+) and ZWIX(-). The stereoselective retention mechanism is based on electrostatically driven intermolecular interactions supported by additional interaction increments mainly determined by the absolute configuration of the chiral C8 and C9 atoms of the quinine and quinidine moieties.


Assuntos
Alcaloides de Cinchona/química , Cinchona/química , Dipeptídeos/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Estereoisomerismo , Temperatura , Termodinâmica
7.
Molecules ; 24(13)2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31288489

RESUMO

Black mulberry is a widely acknowledged ancient traditional medicine. Its extract and constituents have been reported to exert various bioactivities including antimicrobial, hypotensive, analgesic etc. effects. While black mulberry preparations are also used as antispasmodic agents in folk medicine, no related studies are available on its isolated constituents. Through an extensive chromatographic purification, seven phenolic compounds were isolated from the methanol extract of Morus nigra root bark, including morusin (1), kuwanon U (2), kuwanon E (3), moracin P (4), moracin O (5), albanol A (6), and albanol B (7). A complete NMR signal assignment of moracin P and O was achieved, and related literature errors confusing the identity of moracin derivatives are hereby clarified. Compounds 2, 5 and 7 were identified as strong antispasmodic agents on isolated rat ileum and tracheal smooth muscles, while compound 3, a methoxy derivative of 2, was inactive. Moracin O (5) inhibited the ileal and tracheal smooth muscle contractions with Emax values of 85% and 302 mg, respectively. Those actions were superior as compared with papaverine. Our findings demonstrate that prenylated arylbenzofurans, geranylated flavonoids and Diels-Alder adducts from Morus nigra are valuable antispasmodic agents. Compounds 2, 5 and 7 are suggested as marker compounds for quality control of antispasmodic mulberry preparations. Moracin O (5) is a new lead compound for related drug development initiatives.


Assuntos
Morus/química , Parassimpatolíticos/química , Fenóis/química , Casca de Planta/química , Extratos Vegetais/química , Raízes de Plantas/química , Benzofuranos/metabolismo , Avaliação Pré-Clínica de Medicamentos , Flavanonas/metabolismo , Metanol/química , Parassimpatolíticos/farmacologia , Prenilação , Resorcinóis/metabolismo , Solventes/química , Relação Estrutura-Atividade
8.
Artigo em Inglês | MEDLINE | ID: mdl-30478163

RESUMO

As a consequence of emerging numbers of vulvovaginitis cases caused by azole-resistant and biofilm-forming Candida species, fast and efficient treatment of this infection has become challenging. The problem is further exacerbated by the severe side effects of azoles as long-term-use medications in the recurrent form. There is therefore an increasing demand for novel and safely applicable effective antifungal therapeutic strategies. The small, cysteine-rich, and cationic antifungal proteins from filamentous ascomycetes are potential candidates, as they inhibit the growth of several Candida spp. in vitro; however, no information is available about their in vivo antifungal potency against yeasts. In the present study, we investigated the possible therapeutic application of one of their representatives in the treatment of vulvovaginal candidiasis, Neosartorya fischeri antifungal protein 2 (NFAP2). NFAP2 inhibited the growth of a fluconazole (FLC)-resistant Candida albicans strain isolated from a vulvovaginal infection, and it was effective against both planktonic cells and biofilm in vitro We observed that the fungal cell-killing activity of NFAP2 is connected to its pore-forming ability in the cell membrane. NFAP2 did not exert cytotoxic effects on primary human keratinocytes and dermal fibroblasts at the MIC in vitro. In vivo murine vulvovaginitis model experiments showed that NFAP2 significantly decreases the number of FLC-resistant C. albicans cells, and combined application with FLC enhances the efficacy. These results suggest that NFAP2 provides a feasible base for the development of a fundamental new, safely applicable mono- or polytherapeutic topical agent for the treatment of superficial candidiasis.


Assuntos
Antifúngicos/metabolismo , Antifúngicos/uso terapêutico , Candidíase Vulvovaginal/tratamento farmacológico , Neosartorya/metabolismo , Animais , Candidíase Vulvovaginal/microbiologia , Farmacorresistência Fúngica , Feminino , Citometria de Fluxo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana
9.
Inflammopharmacology ; 26(1): 261-271, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28451776

RESUMO

BACKGROUND: We have developed a novel compound from acetylsalicylic acid (ASA) and 2-amino-2-(hydroxymethyl)-1,3-propanediol (Tris) precursors with ASA-like anti-inflammatory efficacy and reduced the mucosa-damaging side-effects. Our aim was to examine local and remote consequences of ASA-Tris administration in 2-,4-,6-trinitrobenzene-sulfonic acid (TNBS)-induced colitis as compared to ASA or mesalamine (5-aminosalicylate) treatment. METHODS: Sprague-Dawley rats were randomized to five groups (n = 6, each), and TNBS enemas were performed. Group 1 was the negative control; group 2 was the untreated colitis group. 12 hour after colitis induction repeated doses of ASA, ASA-Tris (both 0.55 mmol/kg) and mesalamine (0.77 mmol/kg) were given 3 times daily for 3 days to groups 3-5. On day 3 of colitis, the in vivo histology of the colon and stomach was investigated. Tissue xanthine-oxidoreductase, myeloperoxidase, nitrite/nitrate changes, and circulating TNF-alpha levels were measured. In addition, liver mitochondria were examined with high-resolution respirometry to analyze alterations in the electron transport chain. RESULTS: TNBS enema significantly elevated inflammatory enzyme activities, NO production, TNF-alpha concentration, and induced morphological damage in the colon. ASA-treatment reduced the inflammatory marker levels and mucosal injury in the colon, but gastric tissue damage was present. ASA-Tris- and mesalamine-treatments significantly reduced the cytokine levels, inflammatory enzyme activities, and colonic mucosal damage without inducing gastric injury. Also, ASA significantly reduced the Complex IV-linked respiration of liver mitochondria, which was not observed after ASA-Tris-treatment. CONCLUSION: As compared to ASA, ASA-Tris conjugation provides significant protection against the colonic injury and cytokine-mediated progression of inflammatory events in experimental colitis without influencing the gastric epithelial structure.


Assuntos
Aspirina/farmacologia , Colite/tratamento farmacológico , Colo/efeitos dos fármacos , Metilaminas/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Colite/metabolismo , Colo/metabolismo , Modelos Animais de Doenças , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Masculino , Mesalamina/farmacologia , Nitratos/metabolismo , Nitritos/metabolismo , Peroxidase/metabolismo , Ratos , Ratos Sprague-Dawley , Ácido Trinitrobenzenossulfônico/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
10.
Sci Rep ; 6: 37322, 2016 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-27929032

RESUMO

Phytoecdysteroids like 20-hydroxyecdysone ("ecdysterone") can exert a mild, non-hormonal anabolic/adaptogenic activity in mammals, and as such, are frequently used in food supplements. Spinach is well-known for its relatively low ecdysteroid content. Cyanotis arachnoidea, a plant native in China, is among the richest sources of phytoecdysteroids, and extracts of this plant are marketed in tons per year amounts via the internet at highly competitive prices. Here we report the investigation of a series of food supplements produced in Germany and claimed to contain spinach extracts. Twelve ecdysteroids including two new compounds were isolated and utilized as marker compounds. A comparative analysis of the products with Cyanotis and spinach extracts provides evidence that they were manufactured from Cyanotis extracts instead of spinach as stated. Based on the chromatographic fingerprints, 20-hydroxyecdysone 2- and 3-acetate are suggested as diagnostic markers for related quality control. This case appears to represent an unusual type of dietary supplement counterfeiting: undeclared extracts from alternative plants would supposedly 'guarantee' product efficacy.


Assuntos
Commelinaceae/química , Suplementos Nutricionais/normas , Ecdisteroides/análise , Spinacia oleracea/química , Animais , China , Ecdisona/análise , Ecdisona/isolamento & purificação , Ecdisteroides/isolamento & purificação , Ecdisterona/análise , Ecdisterona/isolamento & purificação , Alemanha , Fitosteróis/análise , Fitosteróis/isolamento & purificação , Extratos Vegetais/química , Controle de Qualidade
11.
Chem Sci ; 7(4): 2666-2673, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28660039

RESUMO

Anuroctoxin (AnTx), a 35-amino-acid scorpion toxin containing four disulfide bridges, is a high affinity blocker of the voltage-gated potassium channel Kv1.3, but also blocks Kv1.2. To improve potential therapeutic use of the toxin, we have designed a double substituted analog, [N17A/F32T]-AnTx, which showed comparable Kv1.3 affinity to the wild-type peptide, but also a 2500-fold increase in the selectivity for Kv1.3 over Kv1.2. In the present study we have achieved the chemical synthesis of a Sec-analog in which all cysteine (Cys) residues have been replaced by selenocysteine (Sec) forming four diselenide bonds. To the best of our knowledge this is the first time to replace, by chemical synthesis, all disulfide bonds with isosteric diselenides in a peptide/protein. Gratifyingly, the key pharmacological properties of the Sec-[N17A/F32T]-AnTx are retained since the peptide is functionally active. We also propose here a combined experimental and theoretical approach including NOE- and 77Se-based NMR supplemented by MD simulations for conformational and dynamic characterization of the Sec-[N17A/F32T]-AnTx. Using this combined approach allowed us to attain unequivocal assignment of all four diselenide bonds and supplemental MD simulations allowed characterization of the conformational dynamics around each disulfide/diselenide bridge.

12.
J Nat Prod ; 78(10): 2339-45, 2015 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-26465254

RESUMO

Increasing the activation of protein kinase B (Akt) has been suggested as a key signaling step in the nonhormonal anabolic activity of the phytoecdysteroid 20-hydroxyecdysone (20E) in mammals. Base-catalyzed autoxidation of this compound was shown previously to yield interesting B-ring-modified analogues. Herein is reported a thorough study on this reaction, resulting in the preparation and complete NMR spectroscopic assignments of calonysterone (5) and its previously overlooked desmotropic pair (7), along with two new sensitive metabolites of 20E. The two isomers showed considerable stability in solution. Time dependency of the reaction for yield optimization is also presented; by means of analytical HPLC, the two desmotropes can reach a maximum combined yield of >90%. The activity of these compounds on Akt phosphorylation was tested in murine skeletal muscle cells. Compounds 2 and 5 showed more potent activity than 20E in increasing Akt activation, while compound 7 exerted an opposite effect. As such, the present study provides the first direct evidence for a pair of desmotropes exerting significantly different bioactivities.


Assuntos
Commelinaceae/química , Medicamentos de Ervas Chinesas/química , Ecdisterona/metabolismo , Músculo Esquelético/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Ecdisterona/isolamento & purificação , Camundongos , Estrutura Molecular , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/efeitos dos fármacos , Oxirredução , Fosforilação , Raízes de Plantas/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
13.
Nat Prod Commun ; 10(4): 595-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25973485

RESUMO

Phytochemical studies of the roots and aerial parts of endemic Arnebia purpurea S. Erik & H. Sumbul resulted in the isolation and characterization of four naphthoquinones [isovalerylalkannin (1), α-methyl-n-butanoyl alkannin (2), acetylalkannin (3), and alkannin (4)], a triterpene derivative [3-O-acetyl-oleanolic acid (5)], a steroid [ß-sitosterol (6)], three flavonoid glycosides [isorhamnetin-3-O-rutinoside (7), kaempferol-3-O-rutinoside (8), kaempferol 3-O-(5"-acetyl) apiofuranoside 7-O-rhamnopyranoside (9)] and a phenolic acid [rosmarinic acid (10)]. 3-O-Acetyl-oleanolic acid, isorhamnetin-3-O-rutinoside, kaempferol-3-O-mrutinoside, and kaempferol 3-O-(5"-acetyl) apiofuranoside 7-O-rhamnopyranoside are reported from an Arnebia species for the first time. Cytotoxic activities on L929 murine fibrosarcoma cell line of the isolated compounds were investigated using MTT assay. Naphthoquinones (1-4) showed intermediate cytotoxic activity in comparison with the standard, doxorubicin.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Boraginaceae/química , Naftoquinonas/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Fibrossarcoma/tratamento farmacológico , Camundongos , Naftoquinonas/química , Naftoquinonas/isolamento & purificação , Componentes Aéreos da Planta/química , Raízes de Plantas/química
14.
PLoS One ; 9(1): e87215, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24475253

RESUMO

Osteosarcoma is the most common primary malignant tumor of bone usually occurring in young adolescent and children. This disease has a poor prognosis, because of the metastases in the period of tumor progression, which are usually developed previous to the clinical diagnosis. In this paper, a 2000-year-old ancient bone remain with osteogenic sarcoma was analyzed searching for tumor biomarkers which are closely related to this disease. After a specific extraction SDS-PAGE gel electrophoresis followed by tryptic digestion was performed. After the digestion the samples were measured using MALDI TOF/TOF MS. Healthy bone samples from same archaeological site were used as control samples. Our results show that in the pathological skeletal remain several well known tumor biomarkers are detected such as annexin A10, BCL-2-like protein, calgizzarin, rho GTPase-activating protein 7, HSP beta-6 protein, transferrin and vimentin compared to the control samples. The identified protein biomarkers can be useful in the discovery of malignant bone lesions such as osteosarcoma in the very early stage of the disease from paleoanthropological remains.


Assuntos
Biomarcadores Tumorais/metabolismo , Osso e Ossos/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Osteossarcoma/história , Osteossarcoma/metabolismo , Arqueologia , Biomarcadores Tumorais/genética , Osso e Ossos/patologia , Eletroforese em Gel de Poliacrilamida , História Antiga , Humanos , Hungria , Espectrometria de Massas , Osteossarcoma/genética
15.
J Cardiovasc Transl Res ; 6(3): 411-4, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23463297

RESUMO

We assessed if St. John's Wort (SJW) improves platelet response in patients (pts) resistant to clopidogrel after percutaneous coronary intervention (PCI). Stable angina pts non-responders to 600 mg clopidogrel (P2Y12 reaction units (PRU) >240) were randomized (2:1) to SJW (n = 15) or placebo (n = 8). SJW (300 mg × 3/day) was administrated for 2 weeks after PCI. Platelet reactivity was assessed by VerifyNowTM before (BL), 2 (T1), and 4 weeks (T2) after PCI. PRU significantly changed during protocol in SJW (BL (316 ± 60) vs. T1 (170 ± 87) vs. T2 (220 ± 96), p < 0.0001) and placebo group (BL (288 ± 36) vs. T1 (236 ± 31) vs. T2 (236 ± 62), p = 0.046). Yet, PRU changes from BL were higher at T1 in SJW than in placebo group (Δ%, -47 ± 24 vs. -16 ± 15, p = 0.0033), with no differences at T2 between the groups (Δ%, -30 ± 29 vs. -17 ± 24, p = 0.30). Residual platelet reactivity improved with SJW during the first month post-PCI.


Assuntos
Plaquetas/efeitos dos fármacos , Resistência a Medicamentos , Hypericum , Intervenção Coronária Percutânea , Extratos Vegetais/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Ticlopidina/análogos & derivados , Idoso , Análise de Variância , Bélgica , Plaquetas/metabolismo , Distribuição de Qui-Quadrado , Clopidogrel , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Fitoterapia , Extratos Vegetais/efeitos adversos , Plantas Medicinais , Inibidores da Agregação Plaquetária/efeitos adversos , Testes de Função Plaquetária , Valor Preditivo dos Testes , Estudos Prospectivos , Ticlopidina/efeitos adversos , Ticlopidina/uso terapêutico , Fatores de Tempo , Resultado do Tratamento
16.
J Biomol Screen ; 16(8): 886-94, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21832259

RESUMO

This study provides evidence that quinidine can be used as a probe substrate for ABCB1 in multiple experimental systems both in vitro and in vivo relevant to the blood-brain barrier (BBB). The combination of quinidine and PSC-833 (valspodar) is an effective tool to assess investigational drugs for interactions on ABCB1. Effects of quinidine and substrate-inhibitor interactions were tested in a membrane assay and in monolayer assays. The authors compared quinidine and digoxin as ABCB1 probes in the in vitro assays and found that quinidine was more potent and at least as specific as digoxin in ATPase and monolayer efflux assays employing MDCKII-MDR1 and the rat brain microcapillary endothelial cell system. Brain exposure to quinidine was tested in dual-/triple-probe microdialysis experiments in rats by assessing levels of quinidine in blood and brain. Comparing quinidine levels in dialysate samples from valspodar-treated and control animals, it is evident that systemic/local administration of the inhibitor diminishes the pumping function of ABCB1 at the BBB, resulting in an increased brain penetration of quinidine. In sum, quinidine is a good probe to study ABCB1 function at the BBB. Moreover, quinidine/PSC-833 is an ABCB1-specific substrate/inhibitor combination applicable to many assay systems both in vitro and in vivo.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Animais , Produtos Biológicos/análise , Barreira Hematoencefálica/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Técnicas de Cocultura , Ciclosporinas/farmacologia , Digoxina/farmacologia , Cães , Combinação de Medicamentos , Interações Medicamentosas , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Inibidores Enzimáticos/farmacologia , Imunossupressores/farmacologia , Masculino , Microdiálise , Quinidina/farmacologia , Ratos , Ratos Wistar
17.
J Nat Prod ; 70(5): 884-6, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17417908

RESUMO

Two new natural ecdysteroids, 20,22-didehydrotaxisterone (1) and 1-hydroxy-20,22-didehydrotaxisterone (2), were isolated from the roots of Serratula wolffii. Their structures were elucidated by 1D and 2D NMR spectroscopy and mass spectrometry. The biological activities of these compounds were determined via oral aphid (Acyrthosiphon pisum (Harris)) tests. Compound 1 was inactive and compound 2 exhibited very low toxicity in the oral aphid test. The activities of these two ecdysteroids were in agreement with those of other 22-deoxyecdysteroids.


Assuntos
Asteraceae/química , Ecdisteroides/isolamento & purificação , Plantas Medicinais/química , Animais , Afídeos/efeitos dos fármacos , Ecdisteroides/química , Ecdisteroides/farmacologia , Hungria , Larva/efeitos dos fármacos , Estrutura Molecular , Raízes de Plantas/química
18.
Acta Pharm Hung ; 74(3): 131-41, 2004.
Artigo em Húngaro | MEDLINE | ID: mdl-16318222

RESUMO

Ecdysteroids are known as insect moulting hormones. They have the basic steroid structure, although their physiological effects on mammalians do not show the thymolytic and androgenic side effects of vertebrate type steroid hormones. At the same time, phytoecdysteroids can be used utilizing their anabolic and adaptogenic effects. Ecdysteroids also have a tremendous potential in the most modern therapy. Recently, the biotechnology started to employ ecdysteroids as powerful inducers for gene-switch systems with insertion of modified insect receptor into the malignant cells. Nineteen ecdysteroids were isolated with combined chromatographic methods from the herbs of Silene italica ssp. nemoralis (Waldst. and Kit.) Nyman. The chemical structure of the isolated compounds have been elucidated using spectroscopic methods (x-ray, UV, CD, IR, MS, 1D-, 2D-NMR, HMQC, HMBC, COSY, TOCSY, NOESY, ROESY). Structural determination of two of the five new ecdysteroids is detailed here.


Assuntos
Ecdisteroides/isolamento & purificação , Ecdisteroides/uso terapêutico , Fitoterapia , Silene/química , Ecdisteroides/química , Humanos , Modelos Moleculares
19.
J Nat Prod ; 66(3): 450-1, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12662114

RESUMO

A new natural compound, 9alpha,20-dihydroxyecdysone (1), and two known related compounds, 20-hydroxyecdysone and ecdysone, were isolated from the herb Silene italica ssp. nemoralis. Compound 1 is the first C-9 hydroxylated ecdysteroid with a cis-fused A/B ring junction to have been isolated from a plant source, and its structure was determined using a combination of spectroscopic techniques.


Assuntos
Ecdisona/isolamento & purificação , Plantas Medicinais/química , Silene/química , Ecdisona/análogos & derivados , Ecdisona/química , Hungria , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Estereoisomerismo
20.
Phytochemistry ; 60(4): 409-14, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12031434

RESUMO

Three 3-methylbutanoyl and 3-methylbut-2-enoyl disaccharides isolated from green coffee beans (Coffea arabica) were identified as 3-methylbutanoyl-1-O-beta-D-glucopyranosyl-beta-D-apiofuranoside, 3-methylbutanoyl-6-O-alpha-D-glucopyranosyl-beta-D-fructofuranoside, and 3-methylbut-2-enoyl-1-O-beta-D-glucopyranosyl-beta-D-apiofuranoside. The structures were established by one- and two-dimensional 1H and 13C NMR spectra as well as by ESI MS/MS spectra.


Assuntos
Coffea/química , Dissacarídeos/química , Pentanóis/química , Acilação , Cromatografia/métodos , Cromatografia Líquida de Alta Pressão/métodos , Dissacarídeos/isolamento & purificação , Etiópia , Hidrólise , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Octanóis/química , Extratos Vegetais , Espectrometria de Massas por Ionização por Electrospray , Análise Espectral
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