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1.
J Cell Physiol ; 233(2): 1266-1277, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28488765

RESUMO

Gastric cancer represents a diffuse and aggressive neoplasm, whose mortality index is among the highest in the world. Predisposing factors are E-cadherin mutations, Helicobacter pylori infection, and a diet rich in salted and smoked food, with a low intake of fresh fruits and vegetables. Here, we analyzed the effect of total lipophilic extracts of two Southern Italy tomato varieties, San Marzano and Corbarino, on an in vitro model of gastric cancer, YCC-1, YCC-2 and YCC-3 cell lines, characterized by different aggressiveness. Our results showed a possible role of these two varieties of tomatoes against typical neoplastic features. The treatment with tomato extracts affected cancer cell ability to grow both in adherence and in semisolid medium, reducing also cell migration ability. No toxic effects were observed on non-tumoral cells. We found, on gastric cancer cell lines, effects on both cell cycle progression and apoptosis modulation. The extent of antineoplastic effects, however, did not seem to correlate with the carotenoid content and antioxidant activity of the two tomato varieties. Our data indicate that San Marzano and Corbarino intake might be further considered as nutritional support not only in cancer prevention, but also for cancer patient diet.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Carotenoides/farmacologia , Solanum lycopersicum/química , Neoplasias Gástricas/tratamento farmacológico , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Apoptose/efeitos dos fármacos , Carotenoides/isolamento & purificação , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Frutas/química , Humanos , Itália , Invasividade Neoplásica , Fitoterapia , Plantas Medicinais , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Fatores de Tempo
2.
J Nat Prod ; 72(1): 156-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19067593

RESUMO

The present study describes the effects of sauroine (1), the main alkaloid obtained from Huperzia saururus, on memory retention and learning. To evaluate this, electrophysiological experiments and behavioral tests (step down) were performed on male Wistar rats. The results showed that 1 improved memory retention in the step-down test, significantly increasing hippocampal plasticity. Thus, 1 seems to be a constituent responsible for the activity claimed in folk medicine for H. saururus in Argentina.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Comportamento/efeitos dos fármacos , Huperzia/química , Memória/efeitos dos fármacos , Plantas Medicinais/química , Alcaloides/química , Animais , Argentina , Hipocampo/efeitos dos fármacos , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Wistar
3.
Mol Cancer Ther ; 6(10): 2664-74, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17938260

RESUMO

Human epidermal growth factor receptor-2 (HER2) and epidermal growth factor receptor (EGFR) heterodimerize to activate mitogenic signaling pathways. We have shown previously, using MCF7 subcloned cell lines with graded levels of HER2 expression, that responsiveness to trastuzumab and AG1478 (an anti-EGFR agent), varied directly with levels of HER2 expression. HER2 and EGFR up-regulate vascular endothelial growth factor (VEGF), a growth factor that promotes angiogenesis and participates in autocrine growth-stimulatory pathways that might be active in vitro. Here, we show that trastuzumab, erlotinib, and bevacizumab, individually and in combination, inhibit cell proliferation in a panel of unrelated human breast cancer cell lines, in proportion to their levels of HER2 expression. The combination of all three drugs provided a greater suppression of growth than any single drug or two-drug combination in the high HER2-expressing cell lines (P < 0.001). Combination index analysis suggested that the effects of these drugs in combination were additive. The pretreatment net level of VEGF production in each cell line was correlated with the level of HER2 expression (r = 0.883, P = 0.016). Trastuzumab and erlotinib each reduced total net VEGF production in all cell lines. Multiparameter flow cytometry studies indicated that erlotinib alone and the triple drug combination produced a prolonged but reversible blockade of cells in G1, but did not increase apoptosis substantially. These studies suggest that the effects of two and three-drug combinations of trastuzumab, erlotinib, and bevacizumab might offer potential therapeutic advantages in HER2-overexpressing breast cancers, although these effects are of low magnitude, and are likely to be transient.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Receptores ErbB/metabolismo , Receptor ErbB-2/metabolismo , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Apoptose/efeitos dos fármacos , Bevacizumab , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Cloridrato de Erlotinib , Citometria de Fluxo , Fase G1/efeitos dos fármacos , Humanos , Immunoblotting , Quinazolinas/administração & dosagem , Trastuzumab , Células Tumorais Cultivadas/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo
5.
J Ethnopharmacol ; 111(3): 685-7, 2007 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-17303358

RESUMO

Huperzia saururus is reported in Argentinean popular medicine as a memory improver. Chemical studies have shown that the main constituents of the species are Lycopodium alkaloids. On the basis of this information, a purified alkaloid extract was obtained by alkaline extraction of the aerial parts. The aim of this work was to investigate the effects of intra-hippocampal administration of the purified alkaloid extract (AE) on memory retention in vivo, using a step down test, in order to correlate with previous results obtained in vitro in an electrophysiological model. The AE administration significantly increased the latency time in comparison to control animals. For treated animals the latency time was 37.61 +/- 2.84, 80.94 +/- 2.37, and 180.00 +/- 5.74 s for 1, 5, and 10 ng/rat, respectively versus 14.89 +/- 2.38 s for controls. According to these results there is a good relationship between the ethnopharmacological use and the effects hereby showed.


Assuntos
Alcaloides/farmacologia , Huperzia/química , Memória/efeitos dos fármacos , Extratos Vegetais/farmacologia , Alcaloides/administração & dosagem , Alcaloides/isolamento & purificação , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Comportamento Animal , Relação Dose-Resposta a Droga , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Medicina Tradicional , Componentes Aéreos da Planta , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Ratos , Ratos Wistar
6.
Phytomedicine ; 24: 104-110, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28160849

RESUMO

BACKGROUND: Phlegmariurus saururus is popularly known in Argentina as aphrodisiac. For this reason, it was previously investigated and determined that the decoction of this plant elicits pro-ejaculatory activity and increases the ejaculatory potency in the Fictive Ejaculation Model. HYPOTHESIS/PURPOSE: the decoction of P. saururus facilitates sexual behavior in sexually experienced male rat and induces copulatory behavior in non-copulating male rats. METHODS: The extraction method (decoction) was validated through Selectivity, Accuracy and Precision, by identification of the majority alkaloids, expressed as sauroxine. Male (sexually experienced and noncopulating) and female (receptive) Wistar rats were used to determine sexual behavior. Sildenafil was used as positive control. The following variables were evaluated: Mount Latency, Intromission Latency, Ejaculation Latency, Post Ejaculatory Interval, as well as the Mounts and Intromissions Number. RESULTS: In sexually experienced male rats, P. saururus decoction stimulates sexual arousal and facilitates sexual execution. In noncopulating male rats, this decoction induces copulation with behavioral characteristics similar to sexually experienced animals. CONCLUSION: P. saururus possesses aphrodisiac activity in copulating and noncopulating male rats.


Assuntos
Afrodisíacos/farmacologia , Huperzia/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Comportamento Sexual Animal/efeitos dos fármacos , Animais , Argentina , Feminino , Masculino , Fitoterapia , Ratos , Ratos Wistar
7.
J Ethnopharmacol ; 104(3): 374-8, 2006 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-16325360

RESUMO

Huperzia saururus (Lam.) Trevis. (Lycopodiaceae) known as cola de quirquincho is used in folk medicine to improve memory. The cholinergic neurons of the basal forebrain, including those in the medial septum, and in the vertical limbs of the diagonal band of Broca and the nucleus basalis of Meynert, provide a major source of cholinergic enervation of the cortex and hippocampus. These neurons have also been shown to play an important role in learning and memory processes. Thus, the effects of this traditional Argentinean species were studied in relation to its activity on synaptic transmission in the hippocampus. The alkaloid extract obtained first by decoction of the aerial parts and by subsequent alkaline extraction, was purified by using a Sephadex LH 20 packed column. Electrophysiological experiments were developed with the purified extract (E(2)) on rat hippocampus slices, thus eliciting long-term potentiation (LTP). Results show a marked increase in the hippocampal synaptic plasticity. The threshold value for generation of LTP was 22 +/- 1.01 Hz on average for E(2), while for controls it was 86 +/- 0.92 Hz. All of these factors could explain the use of Huperzia saururus as a memory improver as is reported in the ethnomedicine.


Assuntos
Hipocampo/efeitos dos fármacos , Huperzia , Transmissão Sináptica/efeitos dos fármacos , Animais , Eletrofisiologia , Hipocampo/fisiologia , Técnicas In Vitro , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar
8.
J Neurosurg Sci ; 59(1): 1-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25413777

RESUMO

AIM: Tinnitus is the perception of sound in the absence of an apparent acoustic stimulus. A widespread and highly debilitating disease difficult to cure. Several treatments have been advocated for tinnitus in the last years, including surgery, pharmacotherapy, counseling, cognitive behavioral therapy, sound therapy, but unfortunately without definitive conclusions. The surgery treatments could represent an important therapeutic choice on specific subgroups of tinnitus with defined causes but obviously this approach represent an invasive treatment and it should be considered with extreme caution and then, alternative pharmacological options should be investigated. METHODS: In this retrospective study 30 patients with tinnitus were treated with sulodexide (250 LSU BID, in the morning and in the evening) and melatonin (3 mg in the evening before going to sleep) for 80 days. The evaluations were performed comparing different parameters at basal (T0) and after 40 days (T1) and 80 days (T2) of treatment. RESULTS: The results of Tinnitus Handicap Inventory (THI) and acufenometry showed a significative improvement of tinnitus after treatment with sulodexide and melatonin. In particular, THI total score was reduced from 37±20 to 27±18 (P<0.001) and 21±19 (P<0.001) at T1 and T2, respectively. The percentage of patients with improved symptoms (i.e. reduced score at THI) was 76.7% at T1 and 90.0% at T2. Finally a significant improvement was also detected in the tone audiometry test. No side effects were observed during the treatment period. CONCLUSION: In conclusion, the combined use of sulodexide, a natural glycosaminoglycan with antithrombotic, profibrinolytic and vascular anti-inflammatory properties used in the treatment of many vascular diseases, included the vertigo of vascular origin and melatonin, a neurohormone produced by the pineal gland and related to multiple physiological functions, confirms to an important and promising therapeutically option in the tinnitus management.


Assuntos
Anticoagulantes/administração & dosagem , Antioxidantes/administração & dosagem , Glicosaminoglicanos/administração & dosagem , Melatonina/administração & dosagem , Zumbido/tratamento farmacológico , Idoso , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
9.
Urology ; 39(6): 552-5, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1377434

RESUMO

Prostate-specific antigen (PSA) is a glycoprotein derived from prostatic ductal and acinar epithelial cells. The main clinical use of PSA is as a marker of prostate tumor progression/recurrence. We present a case of a sixty-nine-year-old patient with recurrent endometrioid carcinoma of the prostate (status post-radical prostatectomy, hormonal therapy, and external beam radiation therapy) with normal serum PSA.


Assuntos
Adenocarcinoma/sangue , Antígenos de Neoplasias/sangue , Biomarcadores Tumorais/sangue , Neoplasias da Próstata/sangue , Adenocarcinoma/patologia , Idoso , Humanos , Masculino , Antígeno Prostático Específico , Neoplasias da Próstata/patologia
10.
Urology ; 43(4): 427-34, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7512295

RESUMO

OBJECTIVE: To investigate the distribution and production of alpha 1-antichymotrypsin (ACT) and prostate-specific antigen (PSA) in benign hyperplastic and malignant prostatic tissue, respectively. METHODS: Using monoclonal anti-ACT and anti-PSA IgGs for immunocytochemistry and alkaline phosphatase conjugated 30-mer oligodeoxynucleotide probes for nonradioactive in situ hybridization, tissue specimens were studied from 15 patients with benign prostatic hyperplasia after transurethral resection of the prostate (TURP) and from 9 patients with bladder cancer who underwent cystoprostatectomy. Cancer specimens were from 23 TURP patients and from ultrasound guided core biopsies in 14 patients. Prostate tumors were graded according to the Gleason system. RESULTS: We found no or only occasional small foci of immunostaining for ACT, and no ACT transcripts in the PSA-producing epithelium in areas with benign nodular hyperplasia. By contrast, a high proportion of cells expressed both ACT and PSA in prostate cancers with low Gleason score, as detected by immunocytochemistry and in situ hybridization. Poorly differentiated tumor cells manifested greater variation in immunostaining for both ACT and PSA. As compared to tumors of low Gleason score, high-score tumors less frequently manifested immunostaining for ACT than for PSA, and less frequently generated hybridization signals for both PSA and ACT transcripts. CONCLUSIONS: A significantly higher proportion of serum PSA has been reported to be complexed to ACT in patients with prostate cancer than in patients with benign prostatic hyperplasia. The presently reported lack of ACT production in PSA-containing BPH nodules may contribute to this by making conditions less optimal for complex formation between PSA and ACT. As opposed to this, production of both ACT and PSA in prostate cancers may enhance the complex formation between PSA and ACT.


Assuntos
Antígeno Prostático Específico/biossíntese , Hiperplasia Prostática/metabolismo , Neoplasias da Próstata/metabolismo , alfa 1-Antiquimotripsina/biossíntese , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/análise , Neoplasias da Próstata/química , alfa 1-Antiquimotripsina/análise
11.
Urology ; 42(5): 502-10, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7694414

RESUMO

Prostate-specific antigen (PSA) is a chymotrypsin-like serine protease exclusively produced by the prostate epithelium, and abundant in seminal fluid. In serum, PSA is predominantly complexed to a liver-derived serine protease inhibitor, alpha-1-antichymotrypsin (ACT). A higher proportion of serum PSA is complexed to ACT in prostate cancer than in benign prostate hyperplasia. Since the molecular basis for this is unclear, we have investigated whether or not ACT may be produced in the prostate gland. Immunocytochemistry, using either monoclonal or polyclonal IgGs, demonstrated specific immunostaining for ACT in normal PSA-containing prostate epithelium. Production of ACT in the normal PSA-producing prostate epithelium was demonstrated by means of nonradioactive in situ hybridization using 30-mer anti-sense DNA probes for ACT and for PSA. The ACT and PSA coding transcripts, as detected by in situ hybridization, were distributed perinuclearly, in contrast to the specific immunostaining for ACT and PSA which was most intense in the apical portion of the secretory cells. The results strongly suggest local production and release of ACT by the normal prostate epithelium that may be important for interaction between PSA and ACT in extracellular compartments.


Assuntos
Antígeno Prostático Específico/análise , Próstata/metabolismo , alfa 1-Antiquimotripsina/biossíntese , Técnicas de Cultura , Epitélio/imunologia , Epitélio/metabolismo , Humanos , Imuno-Histoquímica , Hibridização In Situ , Masculino , Próstata/imunologia , Hiperplasia Prostática/metabolismo , Neoplasias da Próstata/metabolismo
12.
Cytometry B Clin Cytom ; 59(1): 10-23, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15108166

RESUMO

BACKGROUND: The presence of cell aggregates in cell suspensions obtained from human solid tumors can interfere with the measurement of cell DNA content of cell singlets, and can confound multiparameter analysis of other measurements on the same cells. Flow cytometric corrections for cell aggregates based on signal pulse shape have not proven to be reliable. Mathematical models have been developed to correct for cell aggregates in binned DNA histogram data, but they are not suitable for the correction of correlated non-DNA measurements obtained on the same cells. METHODS: A total of 21 samples representing a variety of normal and malignant human cell types, including normal lymphocytes, normal sputum, human breast cancer cell lines, and mechanically disaggregated cell suspensions from primary breast cancers and nonsmall cell lung cancers, were studied by laser scanning cytometry (LSC) using the CompuCyte laser scanning cytometer (Cambridge, MA). Nuclear area, nuclear perimeter, and an LSC-based cell texture parameter were measured on approximately 400 cells in each sample, using an air-cooled, violet laser emitting at a wavelength of 405 nm for DAPI excitation, and each cell was classified as a singlet or aggregate by its appearance under direct observation. A "saddle function" provided by CompuCyte was used, together with an algorithm based on the measurements of nuclear area, perimeter, and cell texture (the APT algorithm), to identify cell aggregates and exclude them from the listmode data file. RESULTS: Proportions of cell aggregates in the uncorrected samples ranging from 6 to 56% (mean, 20%) were reduced to proportions ranging from 0 to 7% (mean, 2.4%) after correction. The discriminant function was "tuned" to maintain both average cell singlet purity and average cell singlet yield at >70% over a broad range of cell DNA contents. CONCLUSIONS: A combined approach to cell aggregate detection, which utilizes both the saddle function and the APT algorithm, produces list mode data files that exclude >80% of cell aggregates from samples of disaggregated cell suspensions of human tumors and other sources of clinical material. Such data files are suitable for multiparameter analysis.


Assuntos
Algoritmos , DNA de Neoplasias/análise , Citometria por Imagem/métodos , Neoplasias/patologia , Agregação Celular , Linhagem Celular Tumoral , Análise Fatorial , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Microscopia Confocal , Neoplasias/diagnóstico , Valor Preditivo dos Testes
13.
J Ethnopharmacol ; 66(1): 91-6, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10432213

RESUMO

The chemical composition of the essential oil obtained from Senecio graveolens (Compositae) was analyzed by GLC-MS and the components identified were: isovaleraldehyde, alpha-pinene, alpha-phellandrene, alpha-terpinene, p-cymene, sabinene, gamma-terpinene, 1-methyl-4-isopropenylbenzene, terpinolene, terpinen-4-ol, piperitenone, alpha- and beta-eudesmol. The investigation by the agar-well diffusion method of the antimicrobial activity of the essential oil proved that it has antibacterial effects on Micrococcus luteus ATCC 9341, oxacillin-sensitive and oxacillin-resistant Staphylococcus aureus, as well as antifungal effects on clinically isolated Candida albicans. The minimal inhibitory concentration (MIC) values for M. luteus, oxacillin-sensitive S. aureus and C. albicans were 8.73, 10.91 and 2.13 x 10(-2) mg/ml, respectively. The antimicrobial activity related to known antibiotics was calculated. These results would be compatible with a potential concentration-dependent selectivity of antifungal effect of S. graveolens essential oil. Minimal bactericidal concentration (MBC) is above 87.3 mg/ml. Thus the MBC:MIC ratio would be clearly higher than 1 (above 8), indicating a bacteriostatic effect of the essential oil.


Assuntos
Anti-Infecciosos/farmacologia , Asteraceae/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Antibacterianos , Candida albicans/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Micrococcus luteus/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
14.
J Ethnopharmacol ; 157: 38-44, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25245770

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Huperzia saururus (Lam.) Trevis. has an extensive ethnopharmacological use, mainly because of its aphrodisiac properties. The species is consumed as decoctions or infusions in traditional medicine. The purpose of the present research was to determine if Huperzia saururus is able to increase sexual potency by evaluating the ejaculatory response, in the presence of a decoction in spinal cord transected male rats. MATERIALS AND METHODS: The fictive ejaculation model to record the rhythmic contractions of the bulbospongiosus muscles that accompany ejaculation as an indicator of ejaculation occurrence was used. Sexually experienced male Wistar rats were used. The activation of the fictive ejaculation by the i.v. administration of a decoction was tested, as well as the effects of the oxytocinergic, cholinergic, adrenergic and nitrergic antagonism upon the pro-ejaculatory activity of Huperzia saururus. RESULTS: Decoction (3µg/animal) was able to activate the fictive ejaculation in spinal male rats, producing a statistically significant diminution on the latency of discharge parameter and a statistically significant augment for the number of discharges. Moreover, when sequential treatments using antagonists plus decoction were administered, the effects produced showed that prazosin prevent the pro-ejaculatory effect of the decoction and that the four antagonists assayed blocked the facilitatory effect of Huperzia saururus since the facilitation in the latency of response was prevented, and the number of discharges was reduced. Together these findings support the notion that the decoction exerts an aphrodisiac effect influencing the ejaculatory potency which is partially mediated by oxytocinergic, cholinergic, adrenergic and nitrergic spinal mechanisms. CONCLUSION: In agreement to the ethnopharmacological uses, Huperzia saururus decoction has aphrodisiac properties by influence on the ejaculatory potency.


Assuntos
Afrodisíacos/farmacologia , Ejaculação/efeitos dos fármacos , Huperzia/química , Extratos Vegetais/farmacologia , Animais , Masculino , Medicina Tradicional , Ratos , Ratos Wistar , Traumatismos da Medula Espinal/patologia
15.
Oncogene ; 33(32): 4173-84, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-24213577

RESUMO

The Polycomb group (PcG) proteins regulate stem cell differentiation via the repression of gene transcription, and their deregulation has been widely implicated in cancer development. The PcG protein Enhancer of Zeste Homolog 2 (EZH2) works as a catalytic subunit of the Polycomb Repressive Complex 2 (PRC2) by methylating lysine 27 on histone H3 (H3K27me3), a hallmark of PRC2-mediated gene repression. In skeletal muscle progenitors, EZH2 prevents an unscheduled differentiation by repressing muscle-specific gene expression and is downregulated during the course of differentiation. In rhabdomyosarcoma (RMS), a pediatric soft-tissue sarcoma thought to arise from myogenic precursors, EZH2 is abnormally expressed and its downregulation in vitro leads to muscle-like differentiation of RMS cells of the embryonal variant. However, the role of EZH2 in the clinically aggressive subgroup of alveolar RMS, characterized by the expression of PAX3-FOXO1 oncoprotein, remains unknown. We show here that EZH2 depletion in these cells leads to programmed cell death. Transcriptional derepression of F-box protein 32 (FBXO32) (Atrogin1/MAFbx), a gene associated with muscle homeostasis, was evidenced in PAX3-FOXO1 RMS cells silenced for EZH2. This phenomenon was associated with reduced EZH2 occupancy and H3K27me3 levels at the FBXO32 promoter. Simultaneous knockdown of FBXO32 and EZH2 in PAX3-FOXO1 RMS cells impaired the pro-apoptotic response, whereas the overexpression of FBXO32 facilitated programmed cell death in EZH2-depleted cells. Pharmacological inhibition of EZH2 by either 3-Deazaneplanocin A or a catalytic EZH2 inhibitor mirrored the phenotypic and molecular effects of EZH2 knockdown in vitro and prevented tumor growth in vivo. Collectively, these results indicate that EZH2 is a key factor in the proliferation and survival of PAX3-FOXO1 alveolar RMS cells working, at least in part, by repressing FBXO32. They also suggest that the reducing activity of EZH2 could represent a novel adjuvant strategy to eradicate high-risk PAX3-FOXO1 alveolar RMS.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Proteínas Musculares/antagonistas & inibidores , Fatores de Transcrição Box Pareados/metabolismo , Complexo Repressor Polycomb 2/fisiologia , Rabdomiossarcoma Alveolar/metabolismo , Proteínas Ligases SKP Culina F-Box/antagonistas & inibidores , Adolescente , Apoptose , Diferenciação Celular , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Sobrevivência Celular , Criança , Proteína Potenciadora do Homólogo 2 de Zeste , Feminino , Proteína Forkhead Box O1 , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/metabolismo , Homeostase , Humanos , Masculino , Proteínas Musculares/fisiologia , Fator de Transcrição PAX3 , Proteínas Ligases SKP Culina F-Box/fisiologia
16.
Phytomedicine ; 19(12): 1068-71, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22819449

RESUMO

Sulphated esters of the flavonoids sulphated quercetin 3,7,3',4'-tetrasulphated (QTS) and quercetin 3-acetyl-7,3,4'-trisulphate (ATS), isolated from Flaveria bidentis, have demonstrated anticoagulant and antiplatelet properties. In this study, we examined if both compounds affected the expression of the procoagulant tissue factor (TF) induced by lipopolysaccharide (LPS) on human monocyte. Monocytes were pretreated with different concentrations of each flavonoid (0.1-500 µM), followed by a 4h incubation with LPS in order to induce TF expression. Results of the TF expression showed different behaviors for the two flavonoids studied. A slight inhibitory effect on the TF expression was detected at a QTS concentration of 0.1 µM, but from 1 µM onwards a significant inhibitory effect that remained up to 500 µM could be observed. In contrast, ATS induced a poor inhibitory effect on TF expression at all concentrations tested. These results suggest that QTS has another antithrombotic property, to be added to its already renowned ability as an anticoagulant and antiplatelet compound.


Assuntos
Fibrinolíticos/farmacologia , Flaveria/química , Monócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Quercetina/análogos & derivados , Tromboplastina/metabolismo , Fibrinolíticos/isolamento & purificação , Humanos , Lipopolissacarídeos , Monócitos/metabolismo , Quercetina/isolamento & purificação , Quercetina/farmacologia
18.
Phytomedicine ; 11(6): 539-43, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15500266

RESUMO

Huperzia saururus (Lam.) Trevis. (Lycopodiaceae) is used widely in Argentinian traditional medicine as an aphrodisiac and for memory improvement. An aqueous extract from the aerial parts was obtained by decoction, revealing the presence of alkaloids, among other constituents. By partition with organic solvent in alkaline media, alkaloids were extracted and then purified by gel permeation. We studied the anticholinesterase activity in vitro of the alkaloid extract using erythrocyte membranes and human serum as sources of acetylcholinesterase and pseudocholinesterase, respectively. The results show a marked inhibition of true acetylcholinesterase with an IC50 value of 0.58 microg/ml. Low inhibition of pseudocholinesterase was observed (IC50 value = 191 microg/ml). This shows a selectivity of the extract for the true acetylcholinesterase. Furthermore, chemical study of the bioactive extract was performed by GC-MS, revealing the presence of seven Lycopodium alkaloids, including some not identified previously: sauroxine, 6-hydroxylycopodine, N-acetyllycodine, lycopodine, lycodine, N-methyllycodine, and clavolonine. Further investigations will be undertaken in order to discover which compound/s are responsible for the aqueous extract's acetylcholinesterase activity.


Assuntos
Inibidores da Colinesterase/farmacologia , Huperzia , Fitoterapia , Extratos Vegetais/farmacologia , Acetilcolinesterase/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/administração & dosagem , Inibidores da Colinesterase/uso terapêutico , Relação Dose-Resposta a Droga , Membrana Eritrocítica/enzimologia , Humanos , Concentração Inibidora 50 , Componentes Aéreos da Planta , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico
19.
Phytomedicine ; 8(5): 389-94, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11695883

RESUMO

The antimicrobial activity of the ethanolic extract of Adesmia aegiceras was studied by the agar-well diffusion method. Antibacterial activity against Micrococcus luteus and eight pathogenic bacterial strains as well as antifungal activity against Candida albicans, was detected. Bacterial and fungal strains exhibited similar concentration-response curves (EC50 and Rmax values) and similar MIC. The MBC/MIC was about 8. These data would indicate the potential usefulness of the A. aegiceras extract as a microbiostatic, antiseptic or disinfectant agent. Furthermore, chemical study of the bioactive alcoholic extract was performed, which revealed quercetin, isorhamnetin-3-rutinoside, isovitexin, pinitol and chlorogenic acid as its main components.


Assuntos
Anti-Infecciosos/farmacologia , Fabaceae , Extratos Vegetais/farmacologia , Antibacterianos , Candida albicans/efeitos dos fármacos , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Micrococcus luteus/efeitos dos fármacos , Extratos Vegetais/química , Estruturas Vegetais/química
20.
Nat Toxins ; 3(2): 75-7, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7613738

RESUMO

M. aeruginosa is a cyanophyte frequently found in the water at the San Roque Dam (raw water supply conditioned for human use in Córdoba city) that causes a bad smell and taste, as well as potential toxic hazards of a still unknown extent. A heavy bloom tested by mouse bioassay (i.p.) for the first time on January 27, 1989, revealed toxicity. The dominant cyanobacterial species in the water sample was M. aeruginosa. The lyophilized bloom material (LD50: 14.5 mg/kg body weight) and the toxin isolated (LD50 estimated: 500 micrograms/kg), when administered to mice i.p., induced clinical signs similar to those induced by peptide toxins produced by M. aeruginosa. HPLC detected toxin traces from a sample of drinking water collected on the same day as the bloom. A seasonal follow-up was carried out for the next 4 years in order to compare bloom toxicity values during the most significant water blooms; these never yielded LD50 values lower than 200 mg liophilized bloom material/kg mice.


Assuntos
Microcystis/metabolismo , Peptídeos Cíclicos/análise , Fosfoproteínas Fosfatases/antagonistas & inibidores , Microbiologia da Água , Animais , Argentina , Bioensaio , Cromatografia Líquida de Alta Pressão , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microcistinas , Peptídeos Cíclicos/metabolismo , Peptídeos Cíclicos/toxicidade , Controle de Qualidade , Estações do Ano , Poluentes da Água , Abastecimento de Água/normas
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