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1.
J Clin Med ; 12(8)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37109245

RESUMO

BACKGROUND AND OBJECTIVES: Long-term proton pump inhibitor (PPI) use is frequently encountered in primary care. Its effect on micronutrient absorption is known, as vitamin B12, calcium or vitamin D insufficiency may occur in such patients. MATERIALS AND METHODS: We recruited patients using a PPI (pantoprazole) for >12 months. The control group was represented by subjects attending the general practitioner not taking any PPI in the last 12 months. We excluded subjects using nutritional supplements or with diseases interfering with micronutrient blood levels. All subjects underwent blood sampling with full blood count, iron, ferritin, vitamin D, calcium, sodium, potassium, phosphate, zinc and folate. RESULTS: We recruited 66 subjects: 30 in the PPI group and 36 in the control group. Long-term pantoprazole users had lower red blood cell count but similar hemoglobin. We did not find any significant difference in blood iron, ferritin, vitamin B12 and folate. Vitamin D deficit was observed more frequently in the PPI group (100%) than in controls (30%, p < 0.001), with blood levels lower in pantoprazole consumers. No differences in calcium, sodium and magnesium were observed. Pantoprazole users had lower phosphate levels than controls. Finally, a non-significant trend for zinc deficiency was found in PPI users. CONCLUSIONS: Our study confirms that chronic PPI users may encounter alterations in some micronutrients involved in bone mineral homeostasis. The effect on zinc levels deserves further investigation.

2.
Int J Mol Sci ; 21(7)2020 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-32235371

RESUMO

Curcumin diffuses through cell membranes into the endoplasmic reticulum, mitochondria, and nucleus, where it exerts actions, as an antioxidant property. Therefore, its use has been advocated for chemopreventive, antimetastatic, and anti-angiogenic purposes. We conducted a literature review to summarize studies investigating the relationship between curcumin and colorectal cancer (CRC). In vitro studies, performed on human colon cancer cell lines, showed that curcumin inhibited cellular growth through cycle arrest at the G2/M and G1 phases, as well as stimulated apoptosis by interacting with multiple molecular targets. In vivo studies have been performed in inflammatory and genetic CRC animal models with a chemopreventive effect. To improve curcumin bioavailability, it has been associated with small particles that increase its absorption when orally administered with excellent results on both inflammation and carcinogenesis. Curcumin has been used, moreover, as a component of dietetic formulations for CRC chemoprevention. These combinations showed in vitro and in vivo anticarcinogenetic properties in inflammation-related and genetic CRC. A synergic effect was suggested using an individual constituent dosage, which was lower than that experimentally used "in vivo" for single components. In conclusion, curcumin falls within the category of plant origin substances able to prevent CRC in animals. This property offers promising expectations in humans.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Curcumina/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Estudos Clínicos como Assunto , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Curcumina/química , Curcumina/uso terapêutico , Suplementos Nutricionais , Modelos Animais de Doenças , Composição de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Humanos , Pesquisa Translacional Biomédica
3.
Nutrients ; 11(8)2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31344966

RESUMO

Phytoestrogens are natural substances that have been extensively studied for their beneficial effect on human health. Herein, we analyzed the data of the literature on the role of phytoestrogens in the prevention of colorectal neoproliferative lesions (CNL). Both in vitro and in vivo studies suggest that the beneficial effects of phytoestrogens on CNL mainly depend on their ability to bind estrogen receptor beta (ERß) in the intestinal mucosa and counter ER-alpha (ERα) activity. Epidemiological data demonstrate a correlation between the low prevalence of CNL in Eastern populations and the consumption of soy products (phytoestrogen-enriched diet). However, both observational and interventional studies have produced inconclusive results. In our opinion, these discrepancies depend on an inadequate evaluation of phytoestrogen intake (dietary questionnaires were not aimed at establishing phytoestrogen intake) and absorption (depending mainly on the intestinal microbiota of the analyzed subjects). For this reason, in the present review, we performed an overview of phytoestrogen dietary intake and metabolism to offer the reader the opportunity for a better interpretation of the literature. Future prospective trials focusing on the protective effect of phytoestrogens against CNL should take into account both their dietary intake and absorption, considering the effective role of the intestinal microbiota.


Assuntos
Proliferação de Células , Colo/metabolismo , Neoplasias Colorretais/prevenção & controle , Dieta Saudável , Fitoestrógenos/administração & dosagem , Comportamento de Redução do Risco , Animais , Disponibilidade Biológica , Colo/microbiologia , Colo/patologia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Microbioma Gastrointestinal , Humanos , Valor Nutritivo , Fitoestrógenos/farmacocinética , Prevalência , Fatores de Proteção , Recomendações Nutricionais , Medição de Risco , Fatores de Risco
4.
World J Gastroenterol ; 23(14): 2453-2458, 2017 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-28465629

RESUMO

The main problem of Helicobacter pylori (H. pylori) infection management is linked to antibiotic resistances. This phenomenon has grown in the last decade, inducing a dramatic decline in conventional regimen effectiveness. The causes of resistance are point mutations in bacterial DNA, which interfere with antibiotic mechanism of action, especially clarithromycin and levofloxacin. Therefore, international guidelines have recently discouraged their use in areas with a relevant resistance percentage, suggesting first-line schedules with expected high eradication rates, i.e., bismuth containing or non-bismuth quadruple therapies. These regimens require the daily assumption of a large number of tablets. Consequently, a complete adherence is expected only in subjects who may be motivated by the presence of major disorders. However, an incomplete adherence to antibiotic therapies may lead to resistance onset, since sub-inhibitory concentrations could stimulate the selection of resistant mutants. Of note, a recent meta-analysis suggests that susceptibility tests may be more useful for the choice of first than second-line or rescue treatment. Additionally, susceptibility guided therapy has been demonstrated to be highly effective and superior to empiric treatments by both meta-analyses and recent clinical studies. Conventional susceptibility test is represented by culture and antibiogram. However, the method is not available everywhere mainly for methodology-related factors and fails to detect hetero-resistances. Polymerase chain reaction (PCR)-based, culture-free techniques on gastric biopsy samples are accurate in finding even minimal traces of genotypic resistant strains and hetero-resistant status by the identification of specific point mutations. The need for an invasive endoscopic procedure has been the most important limit to their spread. A further step has, moreover, been the detection of point mutations in bacterial DNA fecal samples. Few studies on clarithromycin susceptibility have shown an overall high sensitivity and specificity when compared with culture or PCR on gastric biopsies. On these bases, two commercial tests are now available although they have shown some controversial findings. A novel PCR method showed a full concordance between tissue and stool results in a preliminary experience. In conclusion, despite poor validation, there is increasing evidence of a potential availability of noninvasive investigations able to detect H. pylori resistances to antibiotics. These kinds of analysis are currently at a very early phase of development and caution should be paid about their clinical application. Only further studies aimed to evaluate their sensitivity and specificity will afford novel data for solid considerations. Nevertheless, noninvasive molecular tests may improve patient compliance, time/cost of infection management and therapeutic outcome. Moreover, the potential risk of a future increase of resistance to quadruple regimens as a consequence of their use on large scale and incomplete patient adherence could be avoided.


Assuntos
Antibacterianos/uso terapêutico , Técnicas Bacteriológicas , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Técnicas de Diagnóstico Molecular , Medicina de Precisão , DNA Bacteriano/genética , Farmacorresistência Bacteriana , Fezes/microbiologia , Genótipo , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Humanos , Testes de Sensibilidade Microbiana , Mutação , Valor Preditivo dos Testes
5.
Scand J Gastroenterol ; 51(12): 1429-1432, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27687850

RESUMO

PURPOSE: Real-time polymerase chain reaction (RT-PCR) is a widely used technique for bacterial and viral infection diagnosis. Herein, we report our preliminary experience in retrieving H. pylori genetic sequences in stools and analyzing genotypic clarithromycin resistance by RT-PCR (noninvasive), with the aim of comparing this procedure with that performed on biopsy samples (invasive). MATERIALS AND METHODS: After 'in vitro' demonstration of H. pylori DNA detection from pure and stool-mixed bacteria, 52 consecutive patients at the first diagnosis of infection were investigated. DNA was extracted from biopsy tissue and stool samples (THD® Fecal Test, Italy). RT-PCR was performed to detect 23S rRNA encoding bacterial subunit gene and search A2143G, A2142C, A2142G point mutations for clarithromycin resistance assessment. RESULTS: RT-PCR showed H. pylori positive DNA in all infected patients with full concordance between tissue and stool detection (100%). We found A2143G mutation in 10 (19.2%), A2142G in 4 (7.7%) and A2142C in 5 (9.6%) patients; there was a full agreement between biopsy and fecal samples. A2143G was found in all the four A2142G positive cases and in three out of the five A2142C positive strains. Overall clarithromycin resistance rate in our series was 23%. CONCLUSIONS: Despite the need of confirmation on large sample, stool RT-PCR analysis could represent a feasible tool to detect H. pylori DNA sequences and antibiotic resistance point mutations. As compared to tissue molecular analysis, this technique is noninvasive, with potential advantages such as improvement of patient compliance, reduction of diagnostic procedure time/cost and improvement of therapeutic outcome.


Assuntos
Antibacterianos/uso terapêutico , Claritromicina/uso terapêutico , DNA Bacteriano/isolamento & purificação , Farmacorresistência Bacteriana/genética , Infecções por Helicobacter/diagnóstico , Helicobacter pylori , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Fezes/microbiologia , Feminino , Infecções por Helicobacter/tratamento farmacológico , Humanos , Itália , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação Puntual , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
6.
Expert Rev Gastroenterol Hepatol ; 9(7): 993-1003, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25915713

RESUMO

Sorafenib is the only approved systemic treatment for advanced hepatocellular carcinoma patients and all the recently published randomized controlled trials on new systemic drugs have been unsuccessful. This is likely due to a lack of understanding of tumor progression, molecular drivers, and liver toxicity, as well as flaws in trial design. An important signaling pathway in hepatocarcinogenesis is the MEK cascade involved in various cellular responses, including adaptation and survival. A key role in this cascade is played by MEK, of which MEK 1/2 represent the prototypes and an interesting target for new oncological drugs. This review analyzes recent developments and future perspectives on the role of MEK inhibitors in hepatocellular carcinoma treatment.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 2/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Benzimidazóis/uso terapêutico , Difenilamina/análogos & derivados , Difenilamina/uso terapêutico , Humanos , Niacinamida/análogos & derivados , Niacinamida/uso terapêutico , Compostos de Fenilureia/uso terapêutico , Sorafenibe , Sulfonamidas/uso terapêutico
7.
Hepatology ; 62(1): 40-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25613809

RESUMO

UNLABELLED: European and Asian studies report conflicting data on the risk of hepatitis B virus (HBV) reactivation in rheumatologic patients with a previously resolved HBV (prHBV) infection undergoing long-term biologic therapies. In this patient category, the safety of different immunosuppressive biologic therapies, including rituximab, was assessed. A total of 1218 Caucasian rheumatologic patients, admitted consecutively as outpatients between 2001 and 2012 and taking biologic therapies, underwent evaluation of anti-HCV and HBV markers as well as liver amino transferases every 3 months. Starting from January 2009, HBV DNA monitoring was performed in patients with a prHBV infection who had started immunosuppressive biologic therapy both before and after 2009. Patients were considered to have elevated aminotransferase levels if values were >1× upper normal limit at least once during follow-up. We found 179 patients with a prHBV infection (14 treated with rituximab, 146 with anti-tumor necrosis factor-alpha, and 19 with other biologic therapies) and 959 patients without a prHBV infection or other liver disease (controls). The mean age in the former group was significantly higher than the controls. Patients with a prHBV infection never showed detectable HBV DNA serum levels or antibody to hepatitis B surface antigen/hepatitis B surface antigen seroreversion. However, when the prevalence of elevated amino transferases in patients with prHBV infection was compared to controls, it was significantly higher in the former group only for aminotransferase levels >1× upper normal limit but not when aminotransferase levels >2× upper normal limit were considered. CONCLUSION: Among patients with a prHBV infection and rheumatologic indications for long-term biologic therapies, HBV reactivation was not seen; this suggests that universal prophylaxis is not justified and is not cost-effective in this clinical setting.


Assuntos
Artrite/tratamento farmacológico , Terapia Biológica/efeitos adversos , Hepatite B/induzido quimicamente , Fatores Imunológicos/efeitos adversos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto , Idoso , Anticorpos Monoclonais Murinos/administração & dosagem , Anticorpos Monoclonais Murinos/efeitos adversos , Artrite/sangue , Feminino , Humanos , Fatores Imunológicos/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Rituximab , Transaminases/sangue
8.
World J Gastroenterol ; 20(33): 11496-504, 2014 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-25206257

RESUMO

Ulcerative colitis (UC) is a condition at increased risk for colorectal carcinoma (CRC) development. Nowadays, screening and follow-up programs are routinely performed worldwide to promote the early detection of CRCs in subjects with well known risk factors (extent, duration and severity of the disorder). The diffusion of these procedures is presumably the main reason for the marked reduction of cancer incidence and mortality in the course of UC. In addition, chemoprevention has been widely investigated and developed in many medical fields, and aspirin has shown a preventive effect against CRC, while mesalazine has been strongly invoked as a potential chemopreventive agent in UC. However, available studies show some limitations due to the obvious ethical implications of drug withdrawal in UC in order to design a control group. The estrogen receptors (ER) alpha/beta balance seems to have a relevant influence on colorectal carcinogenesis and ER beta appears to parallel apoptosis, and hence an anti-carcinogenic effect. Phytoestrogens are compounds acting as ER beta agonists and have shown a promising chemopreventive effect on sporadic as well as genetically inherited CRC. There is evidence suggesting a role for ERs in UC-related carcinogenesis. In this perspective, since these substances can be considered as dietary supplements and are completely free from side effects, phytoestrogens could be an interesting option for CRC prevention, even when the disease is a consequence of long-term chronic inflammation, as in the course of UC. Further studies of their effects are warranted in both the basic research and clinical fields.


Assuntos
Transformação Celular Neoplásica/metabolismo , Colite Ulcerativa/complicações , Neoplasias Colorretais/etiologia , Receptores de Estrogênio/metabolismo , Transdução de Sinais , Animais , Anti-Inflamatórios/uso terapêutico , Anticarcinógenos/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/prevenção & controle , Receptor beta de Estrogênio/agonistas , Receptor beta de Estrogênio/metabolismo , Humanos , Fitoestrógenos/uso terapêutico , Fatores de Proteção , Receptores de Estrogênio/efeitos dos fármacos , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos
9.
Transpl Int ; 27(7): 696-704, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24673819

RESUMO

Response to interferon-based therapies in HCV recurrence after liver transplantation (LT) is unsatisfactory, and major safety issues aroused in preliminary experience with boceprevir and telaprevir. As transplant community identified HCV viral clearance as a critical matter, efficacious and safe anti-HCV therapies are awaited. The aim of this study was to assess efficacy and safety of intravenous silibinin monotherapy in patients with established HCV recurrence after LT, nonresponders to pegylated interferon and ribavirin. This is a single center, prospective, randomized, parallel-group, double-blind, placebo-controlled, phase 2 trial including 20 patients randomly assigned (3:1) to receive daily 20 mg/kg of intravenous silibinin or saline as placebo, for 14 consecutive days. On day 14 of treatment, viral load decreased by 2.30 ± 1.32 in silibinin group versus no change in the placebo group (P = 0.0002). Sixteen days after the end of the treatment, viral load mean values were similar to baseline. Treatment resulted well tolerated apart from a transient and reversible increase in bilirubin. Neither changes in immunosuppressant through levels nor dosage adjustments were necessary. Silibinin monotherapy has a significant antiviral activity in patients with established HCV recurrence on the graft not responding to standard therapy and confirms safety and tolerability without interaction with immunosuppressive drugs (ClinicalTrials.gov number: NCT01518933).


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Transplante de Fígado , Silimarina/uso terapêutico , Método Duplo-Cego , Humanos , Interferon-alfa/uso terapêutico , Polietilenoglicóis/administração & dosagem , Estudos Prospectivos , Ribavirina/uso terapêutico , Silibina
10.
Carcinogenesis ; 35(7): 1613-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24632492

RESUMO

The promotion and progression of carcinogenesis are susceptible to nutritional interventions aimed at counteracting cancer development. Lipid metabolism is essential in the onset and progression of tumors and for cancer cell survival. In this study, we tested the effects of diets enriched with natural compounds, such as olive oil and salmon oil, in mice that spontaneously develop intestinal polyps (Apc(Min/+) mice). For this purpose, we evaluated polyp number and volume, intestinal mucosa proliferation/apoptosis, estrogen receptors (ERs) expression, fatty acid synthase and 3-hydroxy-3-methylglutaryl coenzyme A (HMGCoA) reductase gene expression and enzymatic activity. Compared with the standard diet, the salmon oil-enriched diet, containing a high percentage of omega-3 polyunsaturated fatty acids, and, to a lesser extent, olive oil-enriched diet reduced polyp number and volume through a reduction of proliferation and a marked proapoptotic effect. These biological effects were mediated by an inhibition of fatty acid synthase and HMGCoA reductase gene expression and activity and an increase of ERß/ERα ratio. Our findings suggest that a proper dietary lifestyle could contribute to primary cancer prevention.


Assuntos
Proteína da Polipose Adenomatosa do Colo/fisiologia , Apoptose , Neoplasias do Colo/prevenção & controle , Ácidos Graxos Ômega-3/uso terapêutico , Pólipos Intestinais/prevenção & controle , Óleos de Plantas/administração & dosagem , Animais , Western Blotting , Proliferação de Células , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Hidroximetilglutaril-CoA Redutases/genética , Hidroximetilglutaril-CoA Redutases/metabolismo , Mucosa Intestinal/metabolismo , Pólipos Intestinais/metabolismo , Pólipos Intestinais/patologia , Metabolismo dos Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microssomos/enzimologia , Azeite de Oliva , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor fas/genética , Receptor fas/metabolismo
11.
World J Gastroenterol ; 19(27): 4325-33, 2013 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-23885143

RESUMO

AIM: To assess the safety and effect of the supplementation of a patented blend of dietary phytoestrogens and insoluble fibers on estrogen receptor (ER)-ß and biological parameters in sporadic colonic adenomas. METHODS: A randomized, double-blind placebo-controlled trial was performed. Patients scheduled to undergo surveillance colonoscopy for previous sporadic colonic adenomas were identified, and 60 eligible patients were randomized to placebo or active dietary intervention (ADI) twice a day, for 60 d before surveillance colonoscopy. ADI was a mixture of 175 mg milk thistle extract, 20 mg secoisolariciresinol and 750 mg oat fiber extract. ER-ß and ER-α expression, apoptosis and proliferation (Ki-67 LI) were assessed in colon samples. RESULTS: No adverse event related to ADI was recorded. ADI administration showed a significant increases in ER-ß protein (0.822 ± 0.08 vs 0.768 ± 0.10, P = 0.04) and a general trend to an increase in ER-ß LI (39.222 ± 2.69 vs 37.708 ± 5.31, P = 0.06), ER-ß/ER-α LI ratio (6.564 ± 10.04 vs 2.437 ± 1.53, P = 0.06), terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (35.592 ± 14.97 vs 31.541 ± 11.54, P = 0.07) and Ki-67 (53.923 ± 20.91 vs 44.833 ± 10.38, P = 0.07) approximating statistical significance. A significant increase of ER-ß protein (0.805 ± 0.13 vs 0.773 ± 0.13, P = 0.04), mRNA (2.278 ± 1.19 vs 1.105 ± 1.07, P < 0.02) and LI (47.533 ± 15.47 vs 34.875 ± 16.67, P < 0.05) and a decrease of ER-α protein (0.423 ± 0.06 vs 0.532 ± 0.11, P < 0.02) as well as a trend to increase of ER-ß/ER-α protein in ADI vs placebo group were observed in patients without polyps (1.734 ± 0.20 vs 1.571 ± 0.42, P = 0.07). CONCLUSION: The role of ER-ß on the control of apoptosis, and its amenability to dietary intervention, are supported in our study.


Assuntos
Adenoma/metabolismo , Neoplasias do Colo/metabolismo , Pólipos do Colo/metabolismo , Suplementos Nutricionais , Receptor beta de Estrogênio/metabolismo , Fitoestrógenos/química , Adenoma/diagnóstico , Idoso , Apoptose , Biomarcadores/metabolismo , Biópsia , Proliferação de Células , Neoplasias do Colo/diagnóstico , Pólipos do Colo/diagnóstico , Colonoscopia , Dieta , Método Duplo-Cego , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Microscopia de Fluorescência , Pessoa de Meia-Idade
12.
J Gastrointest Cancer ; 43(1): 13-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22045273

RESUMO

INTRODUCTION: Colorectal cancer is the third cause of death in industrialized countries. Genetic susceptibility and diet are determinant of cancer risk and tumor behavior. Variation in cancer incidence among and within populations with similar dietary patterns suggests that an individual response may reflect interactions with genetic factors, which may modify gene, protein, and metabolite expression patterns. Nutrigenomics, defined as the interaction between nutrition and an individual genome, will likely provide important clues about responders and non-responders to nutritional intervention. DISCUSSION: Epidemiological and experimental studies suggest a protective role of some normal components of daily diet (fish oil, milk, and vegetables), estrogens, and phytoestrogens in colorectal cancer. The effect of estrogen seems to be mediated by their binding to estrogen receptor beta (ER-ß), one of the two estrogen receptors with high affinity for these hormones. Very recently, the demonstration of an involvement of ER-ß in the development of adenomatous polyps of the colon has also been documented, suggesting the use of selective ER-ß agonists in primary colorectal cancer prevention. Phytoestrogens are plant-derived compounds that structurally and functionally act as estrogen agonists in mammals. They are characterized by a higher binding affinity to ER-ß as compared to estrogen receptor alpha (ER-α), the other estrogen receptor subtype. These biological characteristics explain why the administration of phytoestrogens does not produce the classical side effects associated to estrogen administration (cerebro- and cardiovascular accidents, higher incidence of endometrial and breast cancer) and makes these substances potential candidates for colorectal cancer prevention.


Assuntos
Neoplasias Colorretais/etiologia , Dieta , Receptor beta de Estrogênio/fisiologia , Animais , Cálcio da Dieta/administração & dosagem , Neoplasias Colorretais/prevenção & controle , Receptor beta de Estrogênio/agonistas , Peixes , Humanos , Carne , Leite , Obesidade/complicações , Fitoestrógenos/farmacologia , Fitoestrógenos/uso terapêutico , Verduras
13.
Carcinogenesis ; 31(2): 269-74, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19945967

RESUMO

Most sporadic colorectal cancers (CRCs) develop through the adenoma-carcinoma sequence pathway and are initiated by adenomatous polyposis coli (APC) gene mutations. Estrogen receptor beta (ERbeta) is recognized to progressively reduce its expression in adenomatous and carcinomatous tissues in humans. Moreover, ERbeta deficiency enhances small intestinal tumorigenesis in rodents. In the Apc(Min/+) mouse model, we evaluated intestinal polyp development and ERbeta expression plus other biological parameters influencing tumor growth (epithelial cell proliferation, apoptosis and migration) following the addition of a combination of the ERbeta-selective agonist silymarin (SIL) and/or lignin (LIG) to a high-fat/low-fiber diet. Forty-five Apc(Min/+) mice were divided in four groups: animals fed on the tumorigenic high-fat/low-fiber diet, the tumorigenic diet supplemented with SIL (0.02%) or purified LIG (6.24%) or SIL (0.005%) + LIG (6.24%). In these animals, we assessed polyp number and volume and their degree of dysplasia together with ERbeta messenger RNA (mRNA) and protein levels and epithelial cell proliferation, migration and apoptosis. The latter group of parameters was evaluated in normal and adenomatous mucosa and the results compared with those found in wild-type (WT) mice fed on the control diet. The addition of SIL or LIG to the diet and even more the specific combination of the two significantly counteracted intestinal tumorigenesis and increased ERbeta mRNA and protein levels. Cell proliferation and apoptosis were rebalanced and cell migration accelerated, restoring values similar to those observed in WT animals. Our results further support a protective effect of ERbeta in CRC suggesting the use of the combination of SIL-LIG as a potential approach against CRC development.


Assuntos
Proteína da Polipose Adenomatosa do Colo/fisiologia , Dieta , Receptor beta de Estrogênio/metabolismo , Neoplasias Intestinais/metabolismo , Neoplasias Intestinais/patologia , Adenoma/etiologia , Adenoma/metabolismo , Adenoma/patologia , Animais , Apoptose , Western Blotting , Proliferação de Células , Modelos Animais de Doenças , Receptor beta de Estrogênio/genética , Técnicas Imunoenzimáticas , Marcação In Situ das Extremidades Cortadas , Neoplasias Intestinais/etiologia , Pólipos Intestinais/etiologia , Pólipos Intestinais/metabolismo , Pólipos Intestinais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
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