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1.
Microorganisms ; 12(2)2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38399808

RESUMEN

Fusarium root and crown rot (FRCR) negatively impact several economically important plant species. Cover crops host different soil and residue microbiomes, thereby potentially influencing pathogen load and disease severity. The carryover effect of cover crops on FRCR in barley and soybean was investigated. Field trials were conducted in Prince Edward Island, Canada. Two cover crops from each plant group, including forbs, brassicas, legumes, and grasses, were grown in a randomized complete block design with barley and soybean planted in split plots the following year. Barley and soybean roots were assessed for FRCR through visual disease rating and Fusarium spp. were isolated from diseased tissue. Fungal and bacterial communities in cover crop residues were quantified using amplicon sequencing. The disease-suppressive effects of soil were tested in greenhouse studies. The results indicated that sorghum-sudangrass-associated microbiomes suppress Fusarium spp., leading to reduced FRCR in both barley and soybean. The oilseed radish microbiome had the opposite effect, consequently increasing FRCR incidence in barley and soybean. The results from this study indicate that cover crop residue and the associated soil microbiome influence the incidence and severity of FRCR in subsequent crops. This information can be used to determine cover cropping strategies in barley and soybean production systems.

2.
J Berry Res ; 6(2): 125-136, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27583064

RESUMEN

BACKGROUND: We recently reported that a cranberry proanthocyanidin rich extract (C-PAC) induces autophagic cell death in apoptotic resistant esophageal adenocarcinoma (EAC) cells and necrosis in autophagy resistant cells. EAC is characterized by high morbidity and mortality rates supporting development of improved preventive interventions. OBJECTIVE: The current investigation sought to investigate the role of reactive oxygen species (ROS) in the context of C-PAC induced cell death. METHODS: A panel of human esophageal cell lines of EAC or BE (Barrett's esophagus) origin were treated with C-PAC and assessed for ROS modulation using CellROX® Green reagent and the Amplex Red assay to specifically measure hydrogen peroxide levels. RESULTS: C-PAC significantly increased ROS levels in EAC cells, but significantly reduced ROS levels in CP-C BE cells. Increased hydrogen peroxide levels were also detected in C-PAC treated EAC cells and supernatant; however, hydrogen peroxide levels were significantly increased in medium alone, without cells, suggesting that C-PAC interferes or directly acts on the substrate. Hydrogen peroxide levels did not change in C-PAC treated CP-C BE cells. CONCLUSION: These experiments provide additional mechanistic insight regarding C-PAC induced cancer cell death through modulation of ROS. Additional research is warranted to identify specific ROS species associated with C-PAC exposure.

3.
J Agric Food Chem ; 60(23): 5693-708, 2012 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-22300613

RESUMEN

Breast cancer is the most commonly diagnosed cancer among women worldwide. Many women have become more aware of the benefits of increasing fruit consumption, as part of a healthy lifestyle, for the prevention of cancer. The mechanisms by which fruits, including berries, prevent breast cancer can be partially explained by exploring their interactions with pathways known to influence cell proliferation and evasion of cell-death. Two receptor pathways, estrogen receptor (ER) and tyrosine kinase receptors, especially the epidermal growth factor receptor (EGFR) family, are drivers of cell proliferation and play a significant role in the development of both primary and recurrent breast cancer. There is strong evidence to show that several phytochemicals present in berries such as cyanidin, delphinidin, quercetin, kaempferol, ellagic acid, resveratrol, and pterostilbene interact with and alter the effects of these pathways. Furthermore, they also induce cell death (apoptosis and autophagy) via their influence on kinase signaling. This review summarizes in vitro data regarding the interaction of berry polyphenols with the specific receptors and the mechanisms by which they induce cell death. This paper also presents in vivo data of primary breast cancer prevention by individual compounds and whole berries. Finally, a possible role for berries and berry compounds in the prevention of breast cancer and a perspective on the areas that require further research are presented.


Asunto(s)
Frutas/química , Polifenoles/farmacología , Transducción de Señal/efectos de los fármacos , Animales , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/prevención & control , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Receptores ErbB/genética , Receptores ErbB/metabolismo , Femenino , Humanos , Polifenoles/sangre , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo
4.
Food Chem Toxicol ; 50(2): 227-31, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22079310

RESUMEN

Curcuma longa is a perennial member of the Zingiberaceae family, and cultivated mainly in India, and Southeast Asia. The hypothesis for this study is that turmeric will have distinctive effects from curcumin due to the presence of other bioactive compounds. Thirty Eight-week old Sprague-Dawley rats were separated into three oral feeding groups. Group 1, standard rat chow, Control diet - AIN 93M, group 2 - Curcumin - 700ppm or 0.7g/kg diet, and group 3 - Turmeric - 14,000ppm or 14g/kg diet for a total of 3weeks. One group of rats were feed all three diets only and another group underwent esophagoduodenal anastomosis to evaluate the effects of bioavailability. Curcumin diet did not increase the transcription of mRNA of TNF-alpha, IL-6, iNOS, and COX-2. The average fold change in the mRNAs level was not significant. Whereas turmeric diet increases the levels of IL-6 (1.9-fold, p=0.05), iNOS (4.39-fold, p=0.02), IL-8 (3.11-fold, p=0.04), and COX-2 (2.02-fold, p=0.05), suggesting that turmeric either was more bioavailable or had more affect on pro-inflammatory genes compare to curcumin diet. We have demonstrated the molecular effects of curcumin and turmeric in the role as an anti-inflammatory therapy. However, significant bioavailable differences do occur and must be considered in further chemopreventative investigative trials the setting of reflux esophagitis, Barrett's esophagus, and other upper gastrointestinal cancers.


Asunto(s)
Antioxidantes/metabolismo , Curcuma , Curcumina , Inflamación/metabolismo , Raíces de Plantas , Animales , Disponibilidad Biológica , Biomarcadores , Regulación de la Expresión Génica , Ratas , Ratas Sprague-Dawley
5.
Int J Breast Cancer ; 2012: 147828, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23346406

RESUMEN

Fulvestrant (ICI 182,780; ICI) is approved for the treatment of advanced metastatic breast cancer that is unresponsive to other endocrine therapies. Berries are frequently consumed for their antioxidant, anti-inflammatory, and anticancer potential. In this study, we tested the efficacy of two berry extracts (Jamun-EJAE and red raspberry-RRE) and their bioactive compounds (Delphinidin-Del and Ellagic acid-EA) to inhibit cell proliferation with or without a sublethal dose of ICI in various breast cancer cell lines. ICI-sensitive (LCC1, ZR75-1, and BT474) and -resistant (LCC9, ZR75-1R) cells were subjected to treatment with berry extracts alone (0.1-100 µg/mL) or with a sub-lethal dose of ICI ( 1). EA, in doses tested, did not have any significant effects on any of the cell lines. Finally, we found that the extracts were more effective at lower, physiologically relevant concentrations than at higher experimental doses.

6.
Horm Mol Biol Clin Investig ; 9(2): 127-41, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25436704

RESUMEN

Abstract Breast cancer is the most common cancer diagnosed in women and its global incidence is rising rapidly. Adjuvant hormonal therapy, with antiestrogens (AE) such as tamoxifen and fulvestrant, is highly effective in the treatment of estrogen receptor-positive (ER+) breast cancers and is largely responsible for the increase in survival rates seen in the past four decades. However, nearly 50% of women with ER+ cancer display de novo or acquired resistance to AE therapies. Potential molecular mechanisms driving the resistance phenotype are beginning to be elucidated, allowing further development of more effective therapeutic and preventive strategies to reduce the overall mortality due to breast cancer. Over 70% of breast cancer survivors surveyed report increasing their comsumption of fruits, vegetables, and natural product supplements upon diagnosis. These are rich sources of dietary polyphenols (PPs) that can interact with cell-signaling pathways involved in the development of AE resistance. However, research on mechanisms by which these agents may affect AE resistance and whether PP intake can significantly change breast cancer recurrence is limited. We summarize the available data on the effects of PPs on breast cancer recurrence and the interactions of these compounds with some of the signaling pathways hypothesized to drive cell death and survival involved in the development of AE resistance in breast cancer.

7.
Nutr Cancer ; 63(8): 1256-62, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22043833

RESUMEN

The incidence of esophageal adenocarcinoma in humans is increasing more rapidly than any other malignancy in the United States. Animal studies have demonstrated the efficacy of freeze-dried berry supplementation on carcinogen-induced esophageal squamous cell carcinoma in rats; however, no such studies have been done in esophagoduodenal anastomosis (EDA), an animal model for reflux-induced esophageal adenocarcinoma (EAC) development. Eight-week-old male Sprague-Dawley rats were randomized into 3 groups: EDA + control diet (EDA-CD; n = 10); EDA + 2.5% black raspberry diet (EDA-BRB; n = 11) and EDA + 2.5% blueberry diet (EDA-BB; n = 12). After 2 wk of feeding the respective diets, the rats underwent EDA surgery to induce gastroesophageal reflux and then continued the diet. Measurement of feed intake suggested that all EDA-operated animals had lower feed intake starting at 10 wk after surgery and this was significant close to termination at 24 wk. There were no significant differences in either reflux esophagitis (RE), intestinal metaplasia (IM) (70% in CD, 64% in BRB, and 66% in BB; P = 0.1) or EAC incidence (30% for CD, 34% for BRB, and 25% for BB; P = 0.2) with supplementation. Berry diets did not alter COX-2 levels, but BB diet significantly reduced MnSOD levels (1.23 ± 0.2) compared to control diet (2.05 ± 0.14; P < 0.05). We conclude that a dietary supplementation of freeze-dried BRB and BB at 2.5% (w/w) was not effective in the prevention of reflux-induced esophageal adenocarcinoma in this EDA animal model.


Asunto(s)
Suplementos Dietéticos , Neoplasias Esofágicas/tratamiento farmacológico , Esofagitis Péptica/patología , Esófago/efectos de los fármacos , Frutas/química , Preparaciones de Plantas/farmacología , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/prevención & control , Anastomosis Quirúrgica , Animales , Antocianinas/análisis , Ácido Ascórbico/análisis , Biomarcadores/análisis , Arándanos Azules (Planta)/química , Ciclooxigenasa 2/efectos de los fármacos , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Neoplasias Esofágicas/prevención & control , Esofagitis Péptica/tratamiento farmacológico , Esofagitis Péptica/prevención & control , Esófago/patología , Manipulación de Alimentos/métodos , Liofilización/métodos , Modelos Lineales , Masculino , Ratas , Ratas Sprague-Dawley , Selenio/análisis , Superóxido Dismutasa/efectos de los fármacos , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Aumento de Peso/efectos de los fármacos
8.
Inhal Toxicol ; 23(5): 304-11, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21506880

RESUMEN

BACKGROUND: Gastroesophageal reflux of bile acids plays an important role in the development of Barrett's esophagus (BE)-associated esophageal adenocarcinoma (EAC). Cigarette smoke has been demonstrated to exacerbate the effects of reflux and thus the initial stages of EAC carcinogenesis. To date, no in vivo studies have been conducted to look at the concomitant effects of cigarette smoke and bile acids on EAC incidence. METHODS: In this pilot study, rats that underwent esophagoduodenal anastomosis (EDA) surgery to induce reflux were exposed to whole-body cigarette smoke 3 weeks after surgery. Smoke exposure (135 mg/m³/day) was done for 4 h/day for 5 consecutive days and animals were euthanized after a 48-h recovery period. RESULTS: Exposure to EDA-smoke accelerated the development of BE when compared to EDA-air. The presence of reflux caused a significant 3.5-fold increase in nuclear factor-κB-inducing kinase (NIK) staining (1.47 ± 0.6; p = 0.01). Animals with both reflux and smoking had the highest (10-fold; 4 ± 0.9) induction of cyclooxygenase-2 (COX-2) expression (p < 0.05). Similarly, there was a 10-fold increase in 4-aminobiphenyl (4-ABP) protein adducts identified in all smoke-exposed animals (p < 0.01). CONCLUSION: Cigarette smoke aggravates reflux-induced BE and potentially accelerates the progression of BE to EAC through the loss of manganese superoxide dismutase (MnSOD), and overexpression of NF-κB- and COX-2-mediated factors.


Asunto(s)
Reflujo Biliar/metabolismo , Células Epiteliales/efectos de los fármacos , Esofagitis/metabolismo , Esófago/efectos de los fármacos , Contaminación por Humo de Tabaco/efectos adversos , Anastomosis Quirúrgica , Animales , Reflujo Biliar/etiología , Reflujo Biliar/patología , Biomarcadores/metabolismo , Peso Corporal/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Modelos Animales de Enfermedad , Duodeno/cirugía , Células Epiteliales/metabolismo , Células Epiteliales/patología , Esofagitis/etiología , Esofagitis/patología , Esófago/metabolismo , Esófago/patología , Hemoglobinas/análisis , Hemoglobinas/química , Hemoglobinas/metabolismo , Masculino , FN-kappa B/metabolismo , Estrés Oxidativo/efectos de los fármacos , Proyectos Piloto , Proteínas Serina-Treonina Quinasas/metabolismo , Ratas , Ratas Sprague-Dawley , Quinasa de Factor Nuclear kappa B
9.
J Surg Res ; 171(2): 623-30, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20638682

RESUMEN

BACKGROUND: Bile acids are implicated as etiologic agents in esophageal cancer. We sought to analyze the impact of bile acid exposure on esophageal epithelial cells, Barrett's metaplastic cells (BE), esophageal adenocarcinoma cells (EAC), and esophageal squamous carcinoma cell (ESC). We sought to determine if cellular resistance is related to manganese superoxide dismutase expression. METHODS: Cells were exposed to sodium choleate (CA), sodium deoxycholate (DCA), sodium glycocholate (GCA), sodium taurocholate (TCA), or a 1:1 mixture (MIX) of reagents at concentrations in the range 0.2-0.8 mM. Cell viability was evaluated by MTT assay. Manganese superoxide dismutase (MnSOD) expression was analyzed by Western blot. Statistical analysis was performed using SPSS ver. 17.0, SPSS Inc., Chicago, IL. RESULTS: Bile salt exposure inhibited cell viability in esophageal squamous cells in time- and growth-dependent manner. There was a 50% decrease in cell viability from 4 to 24 h. BE, EAC, and ESC cell lines were more resistant to bile insult. In untreated cell lines, MnSOD expression was significantly decreased in EAC and ESC cell lines compared with esophageal squamous epithelial cells and BE cells (P=0.002). Exposure of ESC cells to bile salt increased MnSOD expression. CONCLUSION: The confirmation of the role of reactive oxygen species (ROS) and bile acids in esophageal carcinogenesis has interesting implications for chemoprevention in patients with reflux esophagitis and Barrett's esophagus. Further studies are necessary to assess the preventative role of antioxidant supplementation.


Asunto(s)
Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Ácidos y Sales Biliares/metabolismo , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Superóxido Dismutasa/metabolismo , Antioxidantes/metabolismo , Esófago de Barrett/metabolismo , Esófago de Barrett/patología , Ácidos y Sales Biliares/toxicidad , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Línea Celular Transformada , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Humanos , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Especies Reactivas de Oxígeno/metabolismo
10.
Nutrition ; 27(2): 182-7, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20538426

RESUMEN

INTRODUCTION: Esophageal cancer consists of two distinct types, esophageal adenocarcinoma (EAC) and squamous cell carcinoma, both of which differ significantly in their etiology. Freeze-dried black raspberry (BRB) has been consistent in its ability to modulate the biomarkers and reduce the incidence of carcinogen-induced squamous cell carcinoma in rats. In our previous studies in the esophagoduodenal anastomosis (EDA) model, we have shown that the early modulation of manganese superoxide dismutase (MnSOD) significantly correlates with the development of reflux-induced EAC in rats. In this study we looked at the short-term effects of a BRB-supplemented diet on the modulation of antioxidant enzymes in reflux-induced esophagitis. METHODS: Male SD rats (8 wk old; n = 3-5) were randomized into three groups--sham-operated, fed control AIN-93M diet (SH-CD), EDA operated and fed either control diet (EDA-CD) or 2.5% (w/w) BRB diet (EDA-BRB). The effect of both reflux and dietary supplementation was analyzed 2 and 4 wk after EDA surgery. RESULTS: Animals in the EDA groups had significantly lower weight gain and diet intake compared to SH-CD (P < 0.05). The sham-operated animals received an average esophagitis score of 0.1 ± 0.1; this increased significantly in EDA-CD animals to 1.8 ± 0.14 (P < 0.001 versus SH-CD) and in EDA-BRB group to 1.7 ± 0.06 (P < 0.001 versus SH-CD), with BE changes also present. However, dietary supplementation of BRB did not alter or ameliorate the grade of esophagitis or the induction of BE. BRB diet caused a 43% increase in MnSOD levels compared to EDA-CD (0.73 ± 0.16; P = 0.09); however, this effect was not statistically significant and at 4 wk, EDA-CD (0.58 ± 0.12) showed an increase in MnSOD expression compared to SH-CD (0.34 ± 0.01). CONCLUSIONS: In conclusion, our data suggest that dietary BRB does not increase the levels of cellular antioxidant enzymes or reduce the levels of lipid peroxidation compared to a control diet, in a short-term study of gastroesophageal reflux induction in the EDA animal model. However, it remains to be tested whether this is indicative of its ineffectiveness to inhibit reflux-induced EAC incidence over the long term.


Asunto(s)
Dieta , Esofagitis Péptica/tratamiento farmacológico , Esofagitis Péptica/etiología , Reflujo Gastroesofágico/complicaciones , Fitoterapia , Rosaceae/química , Animales , Antioxidantes/farmacología , Esofagitis Péptica/patología , Liofilización , Frutas/química , Peroxidación de Lípido , Masculino , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Superóxido Dismutasa/metabolismo
11.
J Surg Res ; 168(1): 42-8, 2011 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-19932903

RESUMEN

BACKGROUND: Esophageal adenocarcinoma (EAC) is the fastest growing cancer in terms of incidence and has a high mortality rate. The animal model to study EAC uses esophagoduodenal anastomosis (EDA) to induce mixed-reflux (bile/acid) causing esophagitis, Barrett's esophagus, and EAC sequence within 6 mo. However, the lack of fully functional stomach in these rats leads to the development of malnutrition. METHODS: We have assessed the ability of a chemically pure, purified ingredient diet (AIN-93M) to reduce surgery-associated malnutrition in rats that have undergone the EDA-surgery. Animals were either sham- (SH) or EDA-operated and fed either a grain-based rodent diet (RD) (SH-RD, n=3; EDA-RD, n=10) or a purified diet (PD) (SH-PD, n=4; EDA-PD, n=11). The animals were weighed periodically for assessment of weight gain and euthanized at the end of 24 wk to measure esophageal tumor incidence. RESULTS: Animals that underwent sham surgery continued to gain weight throughout the study period and no tumors were detected. The EDA-operated animals had significantly lower weight gain compared with sham animals. There was no significant difference in weight gain among EDA animals fed two different types of diets until 9 wk after the surgery. After 9 wk, EDA-RD continued to lose weight significantly, whereas the weight loss leveled in EDA-PD (P<0.001). At termination, neither tissue histopathology nor tumor incidence was significantly different between the groups. CONCLUSION: These results show that compared with a natural ingredient diet, a purified ingredient diet can reduce surgery-associated weight loss in rats with a compromised alimentary tract. This reduction in malnutrition has the potential to reduce the confounding effects of weight loss on future animal studies reported.


Asunto(s)
Anastomosis Quirúrgica/efectos adversos , Anastomosis Quirúrgica/métodos , Sistema Digestivo/fisiopatología , Alimentos Formulados , Pérdida de Peso/fisiología , Adenocarcinoma/prevención & control , Animales , Duodeno/cirugía , Neoplasias Esofágicas/prevención & control , Esófago/cirugía , Masculino , Desnutrición/etiología , Desnutrición/fisiopatología , Modelos Animales , Ratas , Ratas Sprague-Dawley
12.
World J Gastroenterol ; 16(33): 4152-8, 2010 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-20806431

RESUMEN

AIM: To investigate the ability of curcumin to counteract the impact of bile acids on gene expression of esophageal epithelial cells. METHODS: An esophageal epithelial cell line (HET-1A) was treated with curcumin in the presence of deoxycholic acid. Cell proliferation and viability assays were used to establish an appropriate dose range for curcumin. The combined and individual effects of curcumin and bile acid on cyclooxygenase-2 (COX-2) and superoxide dismutase (SOD-1 and SOD-2) gene expression were also assessed. RESULTS: Curcumin in a dose range of 10-100 micromol/L displayed minimal inhibition of HET-1A cell viability. Deoxycholic acid at a concentration of 200 micromol/L caused a 2.4-fold increase in COX-2 gene expression compared to vehicle control. The increased expression of COX-2 induced by deoxycholic acid was partially reversed by the addition of curcumin, and curcumin reduced COX-2 expression 3.3- to 1.3-fold. HET-1A cells exposed to bile acid yielded reduced expression of SOD-1 and SOD-2 genes with the exception that high dose deoxycholic acid at 200 mumol/L led to a 3-fold increase in SOD-2 expression. The addition of curcumin treatment partially reversed the bile acid-induced reduction in SOD-1 expression at all concentrations of curcumin tested. CONCLUSION: Curcumin reverses bile acid suppression of gene expression of SOD-1. Curcumin is also able to inhibit bile acid induction of COX-2 gene expression.


Asunto(s)
Ácidos y Sales Biliares/farmacología , Quimioprevención , Curcumina/farmacología , Células Epiteliales/efectos de los fármacos , Esófago/efectos de los fármacos , Antiinflamatorios no Esteroideos/farmacología , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Ácido Desoxicólico/farmacología , Relación Dosis-Respuesta a Droga , Células Epiteliales/citología , Células Epiteliales/metabolismo , Esófago/citología , Esófago/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa-1
13.
Cancer Prev Res (Phila) ; 3(6): 727-37, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20501861

RESUMEN

To determine whether dietary berries and ellagic acid prevent 17beta-estradiol (E(2))-induced mammary tumors by altering estrogen metabolism, we randomized August-Copenhagen Irish rats (n = 6 per group) into five groups: sham implant + control diet, E(2) implant + control diet (E(2)-CD), E(2) + 2.5% black raspberry (E(2)-BRB), E(2) + 2.5% blueberry (E(2)-BB), and E(2) + 400 ppm ellagic acid (E(2)-EA). Animals were euthanized at early (6 wk), intermediate (18 wk), and late (24 wk) phases of E(2) carcinogenesis, and the mammary tissue was analyzed for gene expression changes using quantitative real-time PCR. At 6 weeks, E(2) treatment caused a 48-fold increase in cytochrome P450 1A1 (CYP1A1; P < 0.0001), which was attenuated by both BRB and BB diets to 12- and 21-fold, respectively (P < 0.001). E(2) did not alter CYP1B1 levels, but both berry and EA diets significantly suppressed it by 11- and 3.5-fold, respectively, from baseline (P < 0.05). There was a 5-fold increase in 17beta-hydroxysteroid dehydrogenase 7 (17betaHSD7), and this was moderately abrogated to approximately 2-fold by all supplementation (P < 0.05). At 18 weeks, CYP1A1 was elevated by 15-fold in E(2)-CD and only E(2)-BB reduced this increase to 7-fold (P < 0.05). Catechol-O-methyltransferase expression was elevated 2-fold by E(2) treatment (P < 0.05), and all supplementation reversed this. At 24 weeks, CYP1A1 expression was less pronounced but still high (8-fold) in E(2)-treated rats. This increase was reduced to 3.2- and 4.6-fold by E(2)-BRB and E(2)-EA, respectively (P < 0.05), but not by E(2)-BB. Supplementation did not alter the effect of E(2) on steroid receptors. The diets also significantly suppressed mammary tumor incidence (10-30%), volume (41-67%), and multiplicity (38-51%; P < 0.05). Berries may prevent mammary tumors by suppressing the levels of E(2)-metabolizing enzymes during the early phase of E(2) carcinogenesis.


Asunto(s)
Arándanos Azules (Planta) , Ácido Elágico/uso terapéutico , Estrógenos/metabolismo , Neoplasias Mamarias Experimentales/prevención & control , Neoplasias Hormono-Dependientes/prevención & control , Fitoterapia , Rosaceae , 17-Hidroxiesteroide Deshidrogenasas/biosíntesis , 17-Hidroxiesteroide Deshidrogenasas/genética , Animales , Hidrocarburo de Aril Hidroxilasas/biosíntesis , Hidrocarburo de Aril Hidroxilasas/genética , Catecol O-Metiltransferasa/biosíntesis , Catecol O-Metiltransferasa/genética , Transformación Celular Neoplásica , Citocromo P-450 CYP1A1/biosíntesis , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1B1 , Ensayos de Selección de Medicamentos Antitumorales , Ácido Elágico/farmacología , Femenino , Frutas , Glutatión Transferasa/biosíntesis , Glutatión Transferasa/genética , Isoenzimas/biosíntesis , Isoenzimas/genética , Neoplasias Mamarias Experimentales/enzimología , Neoplasias Hormono-Dependientes/enzimología , Distribución Aleatoria , Ratas , Ratas Endogámicas , Receptores de Estrógenos/biosíntesis , Receptores de Estrógenos/genética , Receptores de Progesterona/biosíntesis , Receptores de Progesterona/genética
14.
Nutr Cancer ; 60 Suppl 1: 36-42, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19003579

RESUMEN

The hormone 17ss-estradiol (E(2)) causes oxidative DNA damage via redox cycling of its metabolites such as 4-hydroxy estradiol (4E(2)). In this study, ACI rats (8 wk old) were fed either AIN-93M diet or diets supplemented with 0.5% each of mixed berries (strawberry, blueberry, blackberry, and red and black raspberry), blueberry alone (BB; 2.5%), or ellagic acid (EA; 400 ppm) from 2 wk prior to and up to 12 wk of E(2) treatment. The liver DNA was analyzed for the presence of 8-oxo-7,8-dihydroguanine (8-oxodG) and other polar adducts by 32P-postlabeling. Compared to sham treatment, E(2) significantly increased the levels of both 8-oxodG and P-1 subgroup (259% and 214%, respectively; P< 0.05). EA diet significantly reduced E(2)-induced levels of 8-oxodG, P-1, P-2, and PL-1 by 79, 63, 44, and 67%, respectively (P< 0.001). BB diet also significantly reduced the levels of P-1, P-2, and PL-1 subgroups by 77, 43, and 68%, respectively (P< 0.001). Mixed berries were, however, ineffective. In addition, aqueous extracts of berries (2%) and EA (100 microM) were tested for their efficacy in diminishing oxidative DNA adducts induced by redox cycling of 4E(2) catalyzed by copper chloride in vitro. EA was the most efficacious (90%), followed by extracts of red raspberry (70%), blueberry, and strawberry (50% each; P< 0.001).


Asunto(s)
Daño del ADN , Ácido Elágico/farmacología , Frutas , Extractos Vegetales/farmacología , Animales , Antocianinas/análisis , Cobre/toxicidad , Aductos de ADN/análisis , Ácido Elágico/análisis , Estradiol/análogos & derivados , Estradiol/toxicidad , Estrógenos de Catecol , Femenino , Frutas/química , Oxidación-Reducción , Ratas , Ratas Endogámicas ACI
15.
Nutr Cancer ; 60(2): 227-34, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18444155

RESUMEN

Estrogen acts as a complete mammary carcinogen in ACI rats. Prevention studies in this model allowed us to identify agents that are effective against estrogen-induced mammary carcinogenesis. In this study, we investigated efficacy of dietary berries and ellagic acid to reduce estrogen-mediated mammary tumorigenesis. Female ACI rats (8-9 wk) were fed either AIN-93M diet (n = 25) or diet supplemented with either powdered blueberry (n = 19) and black raspberry (n = 19) at 2.5% wt/wt each or ellagic acid (n = 22) at 400 ppm. Animals received implants of 17beta-estradiol 2 wk later, were palpated periodically for mammary tumors, and were euthanized after 24 wk. No differences were found in tumor incidence at 24 wk; however, tumor volume and multiplicity were reduced significantly after intervention. Compared with the control group (average tumor volume = 685 +/- 240 mm3 and tumor multiplicity = 8.0 +/- 1.3), ellagic acid reduced the tumor volume by 75% (P < 0.005) and tumor multiplicity by 44% (P < 0.05). Black raspberry followed closely, with tumor volume diminished by > 69% (P < 0.005) and tumor multiplicity by 37% (P = 0.07). Blueberry showed a reduction (40%) only in tumor volume. This is the first report showing the significant efficacy of both ellagic acid and berries in the prevention of solely estrogen-induced mammary tumors.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Ácido Elágico/farmacología , Estradiol/toxicidad , Frutas , Neoplasias Mamarias Experimentales/prevención & control , Animales , Estradiol/sangre , Femenino , Frutas/química , Neoplasias Mamarias Experimentales/epidemiología , Neoplasias Mamarias Experimentales/patología , Distribución Aleatoria , Ratas , Ratas Endogámicas ACI , Factores de Tiempo
16.
Int J Mol Sci ; 9(3): 327-341, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19325752

RESUMEN

DNA damage is a pre-requisite for the initiation of cancer and agents that reduce this damage are useful in cancer prevention. In this study, we evaluated the ability of whole berries and berry phytochemical, ellagic acid to reduce endogenous oxidative DNA damage. Ellagic acid was selected based on >95% inhibition of 8-oxodeoxyguosine (8-oxodG) and other unidentified oxidative DNA adducts induced by 4-hydroxy-17ss-estradiol and CuCl(2) in vitro. Inhibition of the latter occurred at lower concentrations (10 microM) than that for 8-oxodG (100 microM). In the in vivo study, female CD-1 mice (n=6) were fed either a control diet or diet supplemented with ellagic acid (400 ppm) and dehydrated berries (5% w/w) with varying ellagic acid contents - blueberry (low), strawberry (medium) and red raspberry (high), for 3 weeks. Blueberry and strawberry diets showed moderate reductions in endogenous DNA adducts (25%). However, both red raspberry and ellagic acid diets showed a significant reduction of 59% (p < 0.001) and 48% (p < 0.01), respectively. Both diets also resulted in a 3-8 fold over-expression of genes involved in DNA repair such as xeroderma pigmentosum group A complementing protein (XPA), DNA excision repair protein (ERCC5) and DNA ligase III (DNL3). These results suggest that red raspberry and ellagic acid reduce endogenous oxidative DNA damage by mechanisms which may involve increase in DNA repair.

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