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1.
Pharm Biol ; 56(1): 235-244, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29564971

RESUMO

CONTEXT: Pimenta dioica (L.) Merr. (Myrtaceae) is used in Costa Rican traditional medicine for women's health. Our previous work showed that P. dioica extracts were oestrogenic. OBJECTIVES: This work identifies phytochemicals from P. dioica that are responsible for the plant's oestrogen-like activities. MATERIALS AND METHODS: P. dioica leaves were collected in Costa Rica in 2005. Fractions resulting from chromatographic separation of a methanol extract were tested at 50 µg/mL in a competitive oestrogen receptor-binding assay. Active compounds were isolated by HPLC and identified by NMR and MS. Pure compounds were tested at 1 µM in the oestrogen-responsive SEAP reporter gene assay. The effects on cell viability, cytotoxicity and apoptosis were investigated in breast cancer (MCF-7 and SK-BR3) and gastric cancer (AGS and NCI-N87) cell lines using the ApoTox-Glo and Caspase-Glo assays and qPCR. RESULTS: Quercitrin and three new chromones, including a 2-phenoxychromone, 6,8-di-C-methylcapillarisin (1) were isolated and identified. Compound 1 caused a 6.2-fold increase in SEAP expression at 1 µM (p < 0.05). This activity was blocked by the ER antagonist ICI 182,780. Compound 2 caused a 6.0-fold increase in SEAP, inhibited the growth of MCF-7, AGS and NCI-N87 cells (IC50 54.27, 38.13 and 51.22 µg/mL, respectively), and induced apoptosis via caspase 8 and increased the Bax/Bcl-2 mRNA ratio in MCF-7 cells. Compound 3 was anti-oestrogenic in MCF-7 cells. DISCUSSION AND CONCLUSIONS: Compounds from P. dioica have oestrogenic, anti-oestrogenic and cytotoxic effects that may explain the ethnomedical use of this plant.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Cromonas/farmacologia , Moduladores de Receptor Estrogênico/farmacologia , Neoplasias/tratamento farmacológico , Fitoestrógenos/farmacologia , Pimenta , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/metabolismo , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Ligação Competitiva , Proliferação de Células/efeitos dos fármacos , Cromonas/isolamento & purificação , Cromonas/metabolismo , Relação Dose-Resposta a Droga , Moduladores de Receptor Estrogênico/isolamento & purificação , Moduladores de Receptor Estrogênico/metabolismo , Feminino , Humanos , Concentração Inibidora 50 , Células MCF-7 , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Fitoestrógenos/isolamento & purificação , Fitoestrógenos/metabolismo , Fitoterapia , Pimenta/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Folhas de Planta , Plantas Medicinais , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Estrogênio/metabolismo
2.
Carcinogenesis ; 37(8): 751-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27234654

RESUMO

The purpose of this study was to identify novel colorectal cancer (CRC)-causing alleles in unexplained familial CRC cases. In order to do so, coding regions in five candidate genes (MGMT, AXIN2, CTNNB1, TGFBR1 and TGFBR2) were sequenced in 11 unrelated microsatellite-stable hereditary non-polyposis CRC (MSS HNPCC) cases. Selected genetic variants were genotyped in a discovery set of 27 MSS HNPCC cases and 85 controls. One genetic variant, rs67687202, in TGFBR1 emerged as significant (P = 0.002), and it was genotyped in a replication set of 87 additional MSS HNPCC-like cases and 338 controls where it was also significantly associated with MSS HNPCC cases (P = 0.041). In the combined genotype data, rs67687202 was associated with a moderate increase in CRC risk (OR = 1.68; 95% CI = 1.13-2.50; P = 0.010). We tested a highly correlated SNP rs868 in 723 non-familial CRC cases compared with 629 controls, and it was not significantly associated with CRC risk (P = 0.370). rs868 is contained in a let-7 miRNA binding site in the 3'UTR of TGFBR1, which might provide a functional basis for the association in MSS HNPCC. In luciferase assays, the risk-associated allele for rs868 was associated with half the luciferase expression in the presence of miRNA let-7b-5p compared with protective allele, suggesting more binding of let-7b-5p and less TGFBR1 expression. Thus, rs868 potentially is a CRC risk-causing allele. Our results support the concept that rs868 is associated with lower TGFBR1 expression thereby increasing CRC risk.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA/genética , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Adulto , Idoso , Alelos , Proteína Axina/genética , Sítios de Ligação , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Genótipo , Humanos , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Proteínas Serina-Treonina Quinases/biossíntese , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Proteínas Supressoras de Tumor/genética , beta Catenina/genética
3.
Gastroenterology ; 138(5): 1854-62, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20102720

RESUMO

BACKGROUND & AIMS: Approximately half of the families that fulfill Amsterdam criteria for Lynch syndrome or hereditary nonpolyposis colorectal cancer (HNPCC) do not have evidence of the germline mismatch repair gene mutations that define this syndrome and result in microsatellite instability (MSI). The carcinogenic pathways and the best diagnostic approaches to detect microsatellite stable (MSS) HNPCC tumors are unclear. We investigated the contribution of epigenetic alterations to the development of MSS HNPCC tumors. METHODS: Colorectal cancers were divided into 4 groups: (1) microsatellite stable, Amsterdam-positive (MSS HNPCC) (N = 22); (2) Lynch syndrome cancers (identified mismatch repair mutations) (N = 21); (3) sporadic MSS (N = 92); and (4) sporadic MSI (N = 46). Methylation status was evaluated for CACNAG1, SOCS1, RUNX3, NEUROG1, MLH1, and long interspersed nucleotide element-1 (LINE-1). KRAS and BRAF mutation status was analyzed. RESULTS: MSS HNPCC tumors displayed a significantly lower degree of LINE-1 methylation, a marker for global methylation, than any other group. Although most MSS HNPCC tumors had some degree of CpG island methylation, none presented a high index of methylation. MSS HNPCC tumors had KRAS mutations exclusively in codon 12, but none harbored V600E BRAF mutations. CONCLUSIONS: Tumors from Amsterdam-positive patients without mismatch repair deficiency (MSS HNPCC) have certain molecular features, including global hypomethylation, that distinguish them from all other colorectal cancers. These characteristics could have an important impact on tumor behavior or treatment response. Studies are underway to further assess the cause and effects of these features.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Metilação de DNA , Reparo de Erro de Pareamento de DNA , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Repetições de Microssatélites , Mutação , Proteínas Adaptadoras de Transdução de Sinal/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Feminino , Predisposição Genética para Doença , Instabilidade Genômica , Humanos , Elementos Nucleotídeos Longos e Dispersos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteína 1 Homóloga a MutL , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Linhagem , Fenótipo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras) , Espanha , Proteína 1 Supressora da Sinalização de Citocina , Proteínas Supressoras da Sinalização de Citocina/genética , Estados Unidos , Proteínas ras/genética
4.
Gastroenterology ; 139(3): 788-96, 796.e1-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20638935

RESUMO

BACKGROUND & AIMS: Ten common low-penetrant genetic variants have been consistently associated with colorectal cancer (CRC) risk; little is known about the correlation between these variants and CRC phenotype. Characterization of such a correlation would improve CRC management and prevention programs. We assessed the association between these genetic variants and CRC phenotype in patients and modeled pairwise combinations to detect epistasis. METHODS: The validation population corresponded to a prospective, multicenter, population-based cohort (EPICOLON I) of 1096 patients with newly diagnosed CRC. The replication set was an independent, prospective, multicenter Spanish cohort (EPICOLON II) of 895 patients with newly diagnosed CRC. For individual single nucleotide polymorphism (SNP) association analyses, a multivariate method using logistic regression was applied in EPICOLON I and subsequently prospectively validated in EPICOLON II. Interactions between SNPs were assessed using the likelihood ratio test. RESULTS: Validated results confirmed that the C allele on 8q23.3 (rs16892766) was significantly associated with advanced-stage tumors (odds ratio [OR], 1.48; 95% confidence interval [CI], 1.15-1.90; P value = 4.9 x 10(-3)). The G allele on 8q24.21 (rs6983267) was more common in patients with a familial history of CRC (OR, 2.02; 95% CI, 1.35-3.03; P value = 3.9 x 10(-4)). The combination of rs6983267 on 8q24.21 and rs9929218 on 16q22.2 was associated with a history of colorectal adenoma (carriers of GG and AA, respectively; OR, 2.28; 95% CI, 1.32-3.93; P = 5.0 x 10(-4)). CONCLUSIONS: CRC susceptibility variants at 8q23.3, 8q24.21, and 16q22.2 appear to be associated with cancer phenotype. These findings might be used to develop screening and surveillance strategies.


Assuntos
Cromossomos Humanos Par 16 , Cromossomos Humanos Par 8 , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Polimorfismo de Nucleotídeo Único , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular , Neoplasias Colorretais/patologia , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Razão de Chances , Linhagem , Fenótipo , Estudos Prospectivos , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Espanha
5.
Pharm Biol ; 47(1): 18-25, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20376297

RESUMO

Cranberry, the fresh or dried ripe fruit of Vaccinium macrocarpon Ait. (Ericaceae), is currently used as adjunct therapy for the prevention and symptomatic treatment of urinary tract infections. Data from clinical trials suggest that extracts of cranberry or cranberry juice reduce the bacterial load of E. coli and also suppress the inflammatory symptoms induced by E. coli infections. A methanol extract prepared from 10 kg of dehydrated cranberries did not directly inhibit the growth of E coli strains ATCC 700336 or ATCC 25922 in concentrations up to 256 mug/mL in vitro. However, the methanol extract (CR-ME) inhibited the activity of cyclooxygenase-2, with an IC(50) of 12.8 mug/mL. Moreover, CR-ME also inhibited the NF-kappabeta transcriptional activation in human T lymphocytes with an IC(50) of 19.4 mug/mL, and significantly (p < 0.01) inhibited the release of interleukin (IL)-1beta, IL-6, IL-8 and tumor necrosis factor-alpha from E. coli lipopolysaccharide (LPS)-stimulated human peripheral blood mononuclear cells in vitro, at a concentration of 50 mug/mL. The extract had no effect on inducible nitric oxide synthase activity in the murine macrophage cell line RAW 264.7. The compounds responsible for this activity were identified using a novel LC-MS based assay as ursolic acid and ursolic acid derivatives. Taken together, these data suggest CR-ME and its constituent chemical compounds target specific pathways involved in E. coli-induced inflammation.

6.
Biochem Res Int ; 2019: 6154170, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827928

RESUMO

Label-free detection methods such as the quartz crystal microbalance (QCM) are well suited to the analysis of molecular interactions in complex mixtures such as crude botanical extracts. In the present study, the binding characteristics of epigallocatechin gallate (EGCG) and crude green tea extract solutions to bovine serum albumin (BSA) have been investigated. The adsorbed mass levels onto BSA-functionalized surfaces were measured at various solution concentrations. Langmuir and Freundlich isotherms were used to model the adsorption data. The Langmuir isotherm better described the adsorption behavior with correlations of 0.68 and 0.70 for the EGCG and the crude extract solutions, respectively. The better fit of the Langmuir model indicates that adsorption occurs homogeneously and that aggregation is negligible. The mass saturation is estimated to be 58% higher for the crude green tea solution as compared to the pure EGCG solution (7.9 ng/cm2 for green tea and 5 ng/cm2 for EGCG). The increased adsorption for the crude extract indicates that the additional tea chemical constituents are binding to alternate sites on the protein molecule and that competitive binding is a nondominant effect. However, a reduced adsorption rate for the crude extract was also observed, indicating some presence of competitive mechanisms. The results demonstrate the utility of the QCM for the analysis of protein binding in crude mixtures as well as pure compounds.

7.
Diabetes Care ; 41(5): 985-993, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29678865

RESUMO

OBJECTIVE: Quality improvement (QI) interventions can improve glycemic control, but little is known about their value. We systematically reviewed economic evaluations of QI interventions for glycemic control among adults with type 1 or type 2 diabetes. RESEARCH DESIGN AND METHODS: We used English-language studies from high-income countries that evaluated organizational changes and reported program and utilization-related costs, chosen from PubMed, EconLit, Centre for Reviews and Dissemination, New York Academy of Medicine's Grey Literature Report, and WorldCat (January 2004 to August 2016). We extracted data regarding intervention, study design, change in HbA1c, time horizon, perspective, incremental net cost (studies lasting ≤3 years), incremental cost-effectiveness ratio (ICER) (studies lasting ≥20 years), and study quality. Weighted least-squares regression analysis was used to estimate mean changes in HbA1c and incremental net cost. RESULTS: Of 3,646 records, 46 unique studies were eligible. Across 19 randomized controlled trials (RCTs), HbA1c declined by 0.26% (95% CI 0.17-0.35) or 3 mmol/mol (2 to 4) relative to usual care. In 8 RCTs lasting ≤3 years, incremental net costs were $116 (95% CI -$612 to $843) per patient annually. Long-term ICERs were $100,000-$115,000/quality-adjusted life year (QALY) in 3 RCTs, $50,000-$99,999/QALY in 1 RCT, $0-$49,999/QALY in 4 RCTs, and dominant in 1 RCT. Results were more favorable in non-RCTs. Our limitations include the fact that the studies had diverse designs and involved moderate risk of bias. CONCLUSIONS: Diverse multifaceted QI interventions that lower HbA1c appear to be a fair-to-good value relative to usual care, depending on society's willingness to pay for improvements in health.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 1/economia , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 2/terapia , Melhoria de Qualidade/economia , Adulto , Análise Custo-Benefício , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Masculino , Melhoria de Qualidade/organização & administração , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Análise de Regressão
8.
JAMA Intern Med ; 177(7): 975-985, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28558095

RESUMO

Importance: Quality improvement (QI) interventions can reduce hospital readmission, but little is known about their economic value. Objective: To systematically review economic evaluations of QI interventions designed to reduce readmissions. Data Sources: Databases searched included PubMed, Econlit, the Centre for Reviews & Dissemination Economic Evaluations, New York Academy of Medicine's Grey Literature Report, and Worldcat (January 2004 to July 2016). Study Selection: Dual reviewers selected English-language studies from high-income countries that evaluated organizational or structural changes to reduce hospital readmission, and that reported program and readmission-related costs. Data Extraction and Synthesis: Dual reviewers extracted intervention characteristics, study design, clinical effectiveness, study quality, economic perspective, and costs. We calculated the risk difference and net costs to the health system in 2015 US dollars. Weighted least-squares regression analyses tested predictors of the risk difference and net costs. Main Outcomes and Measures: Main outcomes measures included the risk difference in readmission rates and incremental net cost. This systematic review and data analysis is reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Results: Of 5205 articles, 50 unique studies were eligible, including 25 studies in populations limited to heart failure (HF) that included 5768 patients, 21 in general populations that included 10 445 patients, and 4 in unique populations. Fifteen studies lasted up to 30 days while most others lasted 6 to 24 months. Based on regression analyses, readmissions declined by an average of 12.1% among patients with HF (95% CI, 8.3%-15.9%; P < .001; based on 22 studies with complete data) and by 6.3% among general populations (95% CI, 4.0%-8.7%; P < .001; 18 studies). The mean net savings to the health system per patient was $972 among patients with HF (95% CI, -$642 to $2586; P = .23; 24 studies), and the mean net loss was $169 among general populations (95% CI, -$2610 to $2949; P = .90; 21 studies), reflecting nonsignificant differences. Among general populations, interventions that engaged patients and caregivers were associated with greater net savings ($1714 vs -$6568; P = .006). Conclusions and Relevance: Multicomponent QI interventions can be effective at reducing readmissions relative to the status quo, but net costs vary. Interventions that engage general populations of patients and their caregivers may offer greater value to the health system, but the implications for patients and caregivers are unknown.


Assuntos
Uso Excessivo dos Serviços de Saúde , Readmissão do Paciente/normas , Melhoria de Qualidade/organização & administração , Análise Custo-Benefício , Humanos , Uso Excessivo dos Serviços de Saúde/economia , Uso Excessivo dos Serviços de Saúde/prevenção & controle , Inovação Organizacional
9.
Colloids Surf B Biointerfaces ; 111: 707-12, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23911628

RESUMO

Adsorption characteristics of the model protein bovine serum albumin (BSA) onto gold surfaces were examined using a 5 MHz quartz crystal microbalance. Protein immobilization was executed in the presence and absence of a homogenous self-assembled monolayer (SAM) of NHS-terminated alkanethiols. BSA concentrations in the range of 3.2 × 10(-6) to 1.0 × 10(-3)mol/L were found to saturate both SAM-functionalized and non-functionalized surfaces with similar densities of 450 ± 26 ng/cm(2). The lack of functionalization dependence is attributed to the large protein size relative to the density of available binding sites in either surface condition. The BSA ligand 8-anilino-1-naphthalenesulfonic acid (ANS) was subsequently introduced to the immobilized BSA to determine any effects of the protein immobilization conditions on ligand binding. The rate of ANS binding to BSA was found to increase with increasing BSA concentration used in the immobilization step. This suggests that protein concentration affects morphology and ligand binding affinity without significantly altering adsorption quantity.


Assuntos
Ouro/metabolismo , Técnicas de Microbalança de Cristal de Quartzo/métodos , Soroalbumina Bovina/metabolismo , Adsorção , Naftalenossulfonato de Anilina/metabolismo , Animais , Bovinos , Ligantes , Ligação Proteica
12.
Clin Cancer Res ; 17(7): 1701-12, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21355073

RESUMO

PURPOSE: Several studies have described molecular differences between microsatellite stable hereditary nonpolyposis colorectal cancer (MSS-HNPCC) and microsatellite unstable Lynch syndrome tumors (MSI-HNPCC). These differences highlight the possibility that other instability forms could explain cancer susceptibility in this group of families. The base excision repair (BER) pathway is the major DNA repair pathway for oxidative DNA damage. A defect in this pathway can result in DNA transversion mutations and a subsequent increased cancer risk. Mutations in MUTYH have been associated with increased colorectal cancer (CRC) risk while no association has been described for OGG1 or NUDT1. EXPERIMENTAL DESIGN: We performed mutational screening of the three genes involved in defense against oxidative DNA damage in a set of 42 MSS-HNPCC families. RESULTS: Eight rare variants and 5 frequent variants were found in MSS-HNPCC patients. All variants were previously described by other authors except variant c.285C>T in OGG1. Segregation studies were done and in silico programs were used to estimate the level of amino acid conservation, protein damage prediction, and possible splicing alterations. Variants OGG1 c.137G>A; MUTYH c.1187G>A were detected in Amsterdam I families and cosegregate with cancer. Analysis of OGG1 c.137G>A transcripts showed an inactivation of the splicing donor of exon 1. CONCLUSIONS: Two rare variants (OGG1 c.137G>A; MUTYH c.1187G>A) and one common polymorphism (NUDT1 c.426C>T) were associated with CRC risk. We show that the BER pathway can play a significant role in a number of MSS-HNPCC colorectal cancers. More studies could be of interest in order to gain further understanding of yet unexplained CRC susceptibility cases.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Dano ao DNA , DNA Glicosilases/genética , Enzimas Reparadoras do DNA/genética , Monoéster Fosfórico Hidrolases/genética , Estudos de Casos e Controles , Neoplasias Colorretais Hereditárias sem Polipose/enzimologia , Neoplasias Colorretais Hereditárias sem Polipose/mortalidade , Reparo de Erro de Pareamento de DNA , Intervalo Livre de Doença , Feminino , Dosagem de Genes , Frequência do Gene , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Oxirredução , Mutação Puntual , Mapeamento por Restrição , Análise de Sequência de DNA
13.
Maturitas ; 66(3): 315-22, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20452152

RESUMO

OBJECTIVES: To investigate the biological activities of Justicia pectoralis Jacq. (Acanthaceae), an herbal medicine used in Costa Rica (CR) for the management of menopausal symptoms and dysmenorrhea. STUDY DESIGN: The aerial parts of J. pectoralis were collected, dried and extracted in methanol. To establish possible mechanisms of action of JP for the treatment of menopausal symptoms, the estrogenic and progesterone agonists, and antiinflammatory activities were investigated. MAIN OUTCOME MEASURES: The methanol extract (JP-M) was tested in ER and PR binding assays, a COX-2 enzyme inhibition assay, the ERbeta-CALUX assay in U2-OS cells, as well as reporter and endogenous gene assays in MCF-7 K1 cells. RESULTS: The JP-M extract inhibited COX-2 catalytic activity (IC(50) 4.8 microg/mL); bound to both ERalpha and ERbeta (IC(50) 50 microg/mL and 23.1 microg/mL, respectively); induced estrogen-dependent transcription in the ERbeta-CALUX; and bound to the progesterone receptor (IC(50) 22.8 microg/mL). The extract also modulated the expression of endogenous estrogen responsive genes pS2, PR, and PTGES in MCF-7 cells at a concentration of 20 microg/mL. Activation of a 2 ERE-construct in transiently transfected MCF-7 cells by the extract was inhibited by the estrogen receptor antagonist ICI 182,780, indicating that the effects were mediated through the estrogen receptor. Finally, the extract weakly enhanced the proliferation of MCF-7 cells, however this was not statistically significant as compared with DMSO controls. CONCLUSIONS: Extracts of J. pectoralis have estrogenic, progestagenic and anti-inflammatory effects, and thus have a plausible mechanism of action, explaining its traditional use for menopause and PMS.


Assuntos
Acanthaceae , Anti-Inflamatórios/farmacologia , Menopausa/efeitos dos fármacos , Fitoestrógenos/farmacologia , Extratos Vegetais/farmacologia , Síndrome Pré-Menstrual/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/metabolismo , Dismenorreia/tratamento farmacológico , Estradiol/genética , Estradiol/metabolismo , Feminino , Expressão Gênica/efeitos dos fármacos , Genes , Genes Reporter , Medicina Herbária , Humanos , Fitoestrógenos/uso terapêutico , Fitoterapia , Componentes Aéreos da Planta , Extratos Vegetais/uso terapêutico , Progestinas/farmacologia , Progestinas/uso terapêutico , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
14.
Menopause ; 16(4): 748-55, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19424091

RESUMO

OBJECTIVE: Outcomes from the Women's Health Initiative have demonstrated adverse effects associated with hormone therapy and have prioritized the need to develop new alternative treatments for the management of menopause and osteoporosis. To this end, we have been investigating natural herbal medicines used by Costa Rican women to manage menopausal symptoms. METHODS: Seventeen plant species were collected and extracted in Costa Rica. To establish possible mechanisms of action and to determine their potential future use for menopause or osteoporosis, we investigated the estrogenic activities of the herbal extracts in an estrogen-reporter gene estrogen receptor (ER) beta-Chemically Activated Luciferase Expression assay in U2-OS cells and in reporter and endogenous gene assays in MCF-7 cells. RESULTS: Six of the plant extracts bound to the ERs. Four of the six extracts stimulated reporter gene expression in the ER-beta-Chemically Activated Luciferase Expression assay. All six extracts modulated expression of endogenous genes in MCF-7 cells, with four extracts acting as estrogen agonists and two extracts, Pimenta dioica and Smilax domingensis, acting as partial agonist/antagonists by enhancing estradiol-stimulated pS2 mRNA expression but reducing estradiol-stimulated PR and PTGES mRNA expression. Both P. dioica and S. domingensis induced a 2ERE-luciferase reporter gene in transient transfected MCF-7 cells, which was inhibited by the ER antagonist ICI 182,780. CONCLUSIONS: This work presents a plausible mechanism of action for many of the herbal medicines used by Costa Rican women to treat menopausal symptoms. However, it further suggests that studies of safety and efficacy are needed before these herbs should be used as alternative therapies to hormone therapy.


Assuntos
Menopausa/efeitos dos fármacos , Fitoestrógenos/administração & dosagem , Fitoterapia , Extratos Vegetais/administração & dosagem , Ligação Competitiva , Neoplasias da Mama , Linhagem Celular Tumoral , Costa Rica , Estradiol/análogos & derivados , Estradiol/farmacologia , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/antagonistas & inibidores , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Feminino , Fulvestranto , Expressão Gênica/efeitos dos fármacos , Genes Reporter/genética , Humanos , Oxirredutases Intramoleculares/genética , Luciferases/genética , Fitoestrógenos/efeitos adversos , Extratos Vegetais/efeitos adversos , Extratos Vegetais/metabolismo , Prostaglandina-E Sintases , RNA Mensageiro/análise , Receptores de Progesterona/genética , Transfecção , Fator Trefoil-1 , Proteínas Supressoras de Tumor/genética
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