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1.
PLoS Med ; 21(2): e1004338, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38349899

RESUMEN

BACKGROUND: Emulsifiers are widely used food additives in industrially processed foods to improve texture and enhance shelf-life. Experimental research suggests deleterious effects of emulsifiers on the intestinal microbiota and the metabolome, leading to chronic inflammation and increasing susceptibility to carcinogenesis. However, human epidemiological evidence investigating their association with cancer is nonexistent. This study aimed to assess associations between food additive emulsifiers and cancer risk in a large population-based prospective cohort. METHODS AND FINDINGS: This study included 92,000 adults of the French NutriNet-Santé cohort without prevalent cancer at enrolment (44.5 y [SD: 14.5], 78.8% female, 2009 to 2021). They were followed for an average of 6.7 years [SD: 2.2]. Food additive emulsifier intakes were estimated for participants who provided at least 3 repeated 24-h dietary records linked to comprehensive, brand-specific food composition databases on food additives. Multivariable Cox regressions were conducted to estimate associations between emulsifiers and cancer incidence. Overall, 2,604 incident cancer cases were diagnosed during follow-up (including 750 breast, 322 prostate, and 207 colorectal cancers). Higher intakes of mono- and diglycerides of fatty acids (FAs) (E471) were associated with higher risks of overall cancer (HR high vs. low category = 1.15; 95% CI [1.04, 1.27], p-trend = 0.01), breast cancer (HR = 1.24; 95% CI [1.03, 1.51], p-trend = 0.04), and prostate cancer (HR = 1.46; 95% CI [1.09, 1.97], p-trend = 0.02). In addition, associations with breast cancer risk were observed for higher intakes of total carrageenans (E407 and E407a) (HR = 1.32; 95% CI [1.09, 1.60], p-trend = 0.009) and carrageenan (E407) (HR = 1.28; 95% CI [1.06, 1.56], p-trend = 0.01). No association was detected between any of the emulsifiers and colorectal cancer risk. Several associations with other emulsifiers were observed but were not robust throughout sensitivity analyses. Main limitations include possible exposure measurement errors in emulsifiers intake and potential residual confounding linked to the observational design. CONCLUSIONS: In this large prospective cohort, we observed associations between higher intakes of carrageenans and mono- and diglycerides of fatty acids with overall, breast and prostate cancer risk. These results need replication in other populations. They provide new epidemiological evidence on the role of emulsifiers in cancer risk. TRIAL REGISTRATION: ClinicalTrials.gov NCT03335644.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Próstata , Adulto , Masculino , Humanos , Dieta , Factores de Riesgo , Estudios Prospectivos , Aditivos Alimentarios/efectos adversos , Diglicéridos , Ácidos Grasos
2.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33807577

RESUMEN

Inflammation is a well-characterized critical driver of gastrointestinal cancers. Previous findings have shown that intestinal low-grade inflammation can be promoted by the consumption of select dietary emulsifiers, ubiquitous component of processed foods which alter the composition and function of the gut microbiota. Using a model of colitis-associated cancer, we previously reported that consumption of the dietary emulsifiers carboxymethylcellulose or polysorbate-80 exacerbated colonic tumor development. Here, we investigate the impact of dietary emulsifiers consumption on cancer initiation and progression in a genetical model of intestinal adenomas. In APCmin mice, we observed that dietary emulsifiers consumption enhanced small-intestine tumor development in a way that appeared to be independent of chronic intestinal inflammation but rather associated with emulsifiers' impact on the proliferative status of the intestinal epithelium as well as on intestinal microbiota composition in both male and female mice. Overall, our findings further support the hypothesis that emulsifier consumption may be a new modifiable risk factor for colorectal cancer (CRC) and that alterations in host-microbiota interactions can favor gastrointestinal carcinogenesis in individuals with a genetical predisposition to such disorders.


Asunto(s)
Adenoma/inducido químicamente , Neoplasias Colorrectales/inducido químicamente , Dieta/efectos adversos , Emulsionantes/efectos adversos , Tracto Gastrointestinal/efectos de los fármacos , Intestinos/efectos de los fármacos , Animales , Carboximetilcelulosa de Sodio/química , Carcinogénesis/inducido químicamente , Proliferación Celular/efectos de los fármacos , Femenino , Aditivos Alimentarios/efectos adversos , Microbioma Gastrointestinal/efectos de los fármacos , Inflamación/inducido químicamente , Mucosa Intestinal/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Polisorbatos/química
4.
Mol Ther ; 25(7): 1628-1640, 2017 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-28143741

RESUMEN

Overcoming adverse effects and selectively delivering drug to target cells are two major challenges in the treatment of ulcerative colitis (UC). Lysine-proline-valine (KPV), a naturally occurring tripeptide, has been shown to attenuate the inflammatory responses of colonic cells. Here, we loaded KPV into hyaluronic acid (HA)-functionalized polymeric nanoparticles (NPs). The resultant HA-KPV-NPs had a desirable particle size (∼272.3 nm) and a slightly negative zeta potential (∼-5.3 mV). These NPs successfully mediated the targeted delivery of KPV to key UC therapy-related cells (colonic epithelial cells and macrophages). In addition, these KPV-loaded NPs appear to be nontoxic and biocompatible with intestinal cells. Intriguingly, we found that HA-KPV-NPs exert combined effects against UC by both accelerating mucosal healing and alleviating inflammation. Oral administration of HA-KPV-NPs encapsulated in a hydrogel (chitosan/alginate) exhibited a much stronger capacity to prevent mucosa damage and downregulate TNF-α, thus they showed a much better therapeutic efficacy against UC in a mouse model, compared with a KPV-NP/hydrogel system. These results collectively demonstrate that our HA-KPV-NP/hydrogel system has the capacity to release HA-KPV-NPs in the colonic lumen and that these NPs subsequently penetrate into colitis tissues and enable KPV to be internalized into target cells, thereby alleviating UC.


Asunto(s)
Antiinflamatorios/farmacología , Colitis Ulcerosa/tratamiento farmacológico , Portadores de Fármacos , Ácido Hialurónico/química , Hormonas Estimuladoras de los Melanocitos/farmacología , Nanopartículas/química , Fragmentos de Péptidos/farmacología , Administración Oral , Alginatos/química , Animales , Antiinflamatorios/química , Antiinflamatorios/metabolismo , Quitosano/química , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/metabolismo , Colitis Ulcerosa/patología , Composición de Medicamentos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Expresión Génica , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Humanos , Hidrogeles/química , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/patología , Masculino , Hormonas Estimuladoras de los Melanocitos/química , Hormonas Estimuladoras de los Melanocitos/metabolismo , Ratones , Terapia Molecular Dirigida , Nanopartículas/administración & dosificación , Tamaño de la Partícula , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Células RAW 264.7 , Dodecil Sulfato de Sodio , Electricidad Estática , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
5.
Mol Ther ; 24(10): 1783-1796, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27491931

RESUMEN

The use of nanotechnology for drug delivery has shown great promise for improving cancer treatment. However, potential toxicity, hazardous environmental effects, issues with large-scale production, and potential excessive costs are challenges that confront their further clinical applications. Here, we describe a nanovector made from ginger-derived lipids that can serve as a delivery platform for the therapeutic agent doxorubicin (Dox) to treat colon cancer. We created nanoparticles from ginger and reassembled their lipids into ginger-derived nanovectors (GDNVs). A subsequent characterization showed that GDNVs were efficiently taken up by colon cancer cells. Viability and apoptosis assays and electric cell-substrate impedance-sensing technology revealed that GDNVs exhibited excellent biocompatibility up to 200 µmol/l; by contrast, cationic liposomes at the same concentrations decreased cell proliferation and increased apoptosis. GDNVs were capable of loading Dox with high efficiency and showed a better pH-dependent drug-release profile than commercially available liposomal-Dox. Modified GDNVs conjugated with the targeting ligand folic acid mediated targeted delivery of Dox to Colon-26 tumors in vivo and enhanced the chemotherapeutic inhibition of tumor growth compared with free drug. Current experiments explore the feasibility of producing nature-derived nanoparticles that are effective as a treatment vehicle while potentially attenuating the issues related to traditional synthetic nanoparticles.


Asunto(s)
Neoplasias del Colon/tratamiento farmacológico , Doxorrubicina/administración & dosificación , Lípidos/química , Nanopartículas/química , Zingiber officinale/química , Animales , Apoptosis , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/farmacología , Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Células HT29 , Humanos , Ratones , Nanopartículas/administración & dosificación , Ensayos Antitumor por Modelo de Xenoinjerto
6.
PLoS Genet ; 9(5): e1003483, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23675307

RESUMEN

LXR (Liver X Receptors) act as "sensor" proteins that regulate cholesterol uptake, storage, and efflux. LXR signaling is known to influence proliferation of different cell types including human prostatic carcinoma (PCa) cell lines. This study shows that deletion of LXR in mouse fed a high-cholesterol diet recapitulates initial steps of PCa development. Elevation of circulating cholesterol in Lxrαß-/- double knockout mice results in aberrant cholesterol ester accumulation and prostatic intra-epithelial neoplasia. This phenotype is linked to increased expression of the histone methyl transferase EZH2 (Enhancer of Zeste Homolog 2), which results in the down-regulation of the tumor suppressors Msmb and Nkx3.1 through increased methylation of lysine 27 of histone H3 (H3K27) on their promoter regions. Altogether, our data provide a novel link between LXR, cholesterol homeostasis, and epigenetic control of tumor suppressor gene expression.


Asunto(s)
Carcinoma/genética , Colesterol/metabolismo , Neoplasias Experimentales/genética , Receptores Nucleares Huérfanos/genética , Neoplasia Intraepitelial Prostática/genética , Neoplasias de la Próstata/genética , Animales , Carcinoma/metabolismo , Carcinoma/patología , Dieta Alta en Grasa , Regulación hacia Abajo , Proteína Potenciadora del Homólogo Zeste 2 , Regulación Neoplásica de la Expresión Génica , Histonas/genética , Proteínas de Homeodominio/metabolismo , Humanos , Receptores X del Hígado , Masculino , Metilación , Ratones , Ratones Noqueados , Neoplasias Experimentales/patología , Receptores Nucleares Huérfanos/metabolismo , Complejo Represivo Polycomb 2/metabolismo , Neoplasia Intraepitelial Prostática/patología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Proteínas de Secreción Prostática/metabolismo , Factores de Transcripción/metabolismo
7.
Gastroenterology ; 146(5): 1289-300.e1-19, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24503126

RESUMEN

BACKGROUND & AIMS: Nanoparticles have been explored as carriers of small interfering RNAs (siRNAs) and might be developed to treat patients with inflammatory bowel disease (IBD). Overexpression of CD98 on the surface of colonic epithelial cells and macrophages promotes the development and progression of IBD. We developed an orally delivered hydrogel that releases nanoparticles with single-chain CD98 antibodies on their surface (scCD98 functionalized) and loaded with CD98 siRNA (siCD98). We tested the ability of the nanoparticles to reduce levels of CD98 in the colons of mice with colitis. METHODS: scCD98-functionalized siCD98-loaded nanoparticles were fabricated using a complex coacervation technique. We investigated the cellular uptake and lysosome escape profiles of the nanoparticles in Colon-26 cells and RAW 264.7 macrophages using fluorescence microscopy. Colitis was induced by transfer of CD4(+)CD45RB(high) T cells to Rag(-/-) mice or administration of dextran sodium sulfate to C57BL/6 mice. Mice were then given hydrogel (chitosan and alginate) containing scCD98-functionalized nanoparticles loaded with siCD98 or scrambled siRNA (control) via gavage. RESULTS: The scCD98-functionalized nanoparticles were approximately 200 nm in size and had high affinity for CD98-overexpressing cells. The scCD98-functionalized siCD98-loaded nanoparticles significantly reduced levels of CD98 in Colon-26 cells and RAW 264.7 macrophages, along with production of inflammatory cytokines (tumor necrosis factor α, interleukin-6, and interleukin-12). In mice with colitis, administration of the scCD98-functionalized siCD98-loaded nanoparticles reduced colon expression of CD98. Importantly, the severity of colitis was also reduced compared with controls (based on loss of body weight, myeloperoxidase activity, inflammatory cytokine production, and histological analysis). Approximately 24.1% of colonic macrophages (CD11b(+)CD11c(-)F4/80(+)) in the mice had taken up fluorescently labeled siRNA-loaded nanoparticles within 12 hours of administration. CONCLUSIONS: Nanoparticles containing surface CD98 antibody and loaded with siCD98 reduce expression of this protein by colonic epithelial cells and macrophages, and oral administration decreases the severity of colitis in mice. This nanoparticle in hydrogel (chitosan/alginate) formulation might be developed to treat patients with IBD.


Asunto(s)
Colitis/prevención & control , Colon/metabolismo , Proteína-1 Reguladora de Fusión/genética , Proteína-1 Reguladora de Fusión/inmunología , Terapia Genética/métodos , Nanomedicina/métodos , Nanopartículas , Interferencia de ARN , ARN Interferente Pequeño/administración & dosificación , Anticuerpos de Cadena Única/administración & dosificación , Administración Oral , Alginatos/química , Animales , Línea Celular , Quitosano/química , Colitis/inducido químicamente , Colitis/genética , Colitis/inmunología , Colitis/metabolismo , Colitis/patología , Colon/inmunología , Colon/patología , Sulfato de Dextran , Modelos Animales de Enfermedad , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Hidrogeles , Interleucina-12/metabolismo , Interleucina-6/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , ARN Interferente Pequeño/metabolismo , Índice de Severidad de la Enfermedad , Factores de Tiempo , Factor de Necrosis Tumoral alfa/metabolismo
8.
Anal Chem ; 87(16): 8173-80, 2015 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-26241158

RESUMEN

Better detections of circulating microRNAs (miRNAs) as disease biomarkers could advance diseases diagnosis and treatment. Current analysis methods or sensors for research and applications are challenged by the low concentrations and wide dynamic range (from aM to nM) of miRNAs in a physiological sample. Here, we report a one-step label-free electrochemical sensor comprising a triple-stem DNA-redox probe structure on a gold microelectrode. A new signal amplification mechanism without the need of a redox enzyme is introduced. The novel strategy overcomes the fundamental limitations of microelectrode DNA sensors that fail to generate detectable current, which is primarily due to the limited amount of redox probes in response to the target analyte binding. By employing a reductant, tris(2-carboxyethyl) phosphine hydrochloride (TCEP) in the detection buffer solution, each redox molecule on the detection probe is cyclically oxidized at the electrode and reduced by the reductant; thus, the signal is amplified in situ during the detection period. The combined merits in the diagnosis power of cyclic voltammetry and the high sensitivity of pulse voltammetry enable parallel analysis for method validation and optimization previously inaccessible. As such, the detection limit of miRNA-122 was 0.1 fM via direct readout, with a wide detection range from sub fM to nM. The detection time is within minutes, which is a significant improvement over other macroscopic sensors and other relevant techniques such as quantitative reverse transcription polymerase chain reaction (qRT-PCR). The high selectivity of the developed sensors is demonstrated by the discrimination against two most similar family sequences: miR-122-3p present in serum and 2-mismatch synthetic RNA sequence. Interference such as nonspecific adsorption, a common concern in sensor development, is reduced to a negligible amount by adopting a multistep surface modification strategy. Importantly, unlike qRT-PCR, the microelectrochemical sensor offers direct absolute quantitative readout that is amenable to clinical and in-home point-of-care (POC) applications. The sensor design is flexible, capable of being tailored for detection of different miRNAs of interest. Combined with the fact that the sensor was constructed at microscale, the method can be generalized for high throughput detection of miRNA signatures as disease biomarkers.


Asunto(s)
Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , MicroARNs/análisis , MicroARNs/química , Microelectrodos , Procesamiento de Señales Asistido por Computador
9.
Mol Ther ; 22(1): 69-80, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24025751

RESUMEN

Intestinal CD98 expression plays a crucial role in controlling homeostatic and innate immune responses in the gut. Modulation of CD98 expression in intestinal cells therefore represents a promising therapeutic strategy for the treatment and prevention of inflammatory intestinal diseases, such as inflammatory bowel disease. Here, the advantages of nanoparticles (NPs) are used, including their ability to easily pass through physiological barriers and evade phagocytosis, high loading concentration, rapid kinetics of mixing and resistance to degradation. Using physical chemistry characterizations techniques, CD98 siRNA/polyethyleneimine (PEI)-loaded NPs was characterized (diameter of ~480 nm and a zeta potential of -5.26 mV). Interestingly, CD98 siRNA can be electrostatically complexed by PEI and thus protected from RNase. In addition, CD98 siRNA/PEI-loaded NPs are nontoxic and biocompatible with intestinal cells. Oral administration of CD98/PEI-loaded NPs encapsulated in a hydrogel reduced CD98 expression in mouse colonic tissues and decreased dextran sodium sulfate-induced colitis in a mouse model. Finally, flow cytometry showed that CD98 was effectively downregulated in the intestinal epithelial cells and intestinal macrophages of treated mice. Finally, the results collectively demonstrated the therapeutic effect of "hierarchical nano-micro particles" with colon-homing capabilities and the ability to directly release "molecularly specific" CD98 siRNA in colonic cells, thereby decreasing colitis.


Asunto(s)
Proteína-1 Reguladora de Fusión/química , Inflamación/metabolismo , Mucosa Intestinal/metabolismo , Nanopartículas/química , Polietileneimina/química , ARN Interferente Pequeño/química , Animales , Línea Celular , Supervivencia Celular , Colon/efectos de los fármacos , Colon/metabolismo , Colon/patología , Células Dendríticas/metabolismo , Sulfato de Dextran/efectos adversos , Proteína-1 Reguladora de Fusión/genética , Técnicas de Transferencia de Gen , Inflamación/inducido químicamente , Inflamación/genética , Inflamación/patología , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/metabolismo , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Intestinos/efectos de los fármacos , Intestinos/patología , Macrófagos/metabolismo , Ratones , Nanopartículas/administración & dosificación , Nanopartículas/ultraestructura , ARN Interferente Pequeño/genética
10.
Lab Invest ; 94(9): 950-65, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25068660

RESUMEN

Inflammatory bowel diseases (IBD) are chronic inflammatory conditions of the gastrointestinal (GI) tract associated with an increased risk of colorectal cancer (CRC). Current treatments for both IBD and colitis-associated CRC suffer from numerous side effects. Parthenolide (PTL) is a sesquiterpene lactone with anti-inflammatory activity, and previous studies have demonstrated that PTL is a potent inhibitor of the NF-κB pathway. Micheliolide (MCL), substantially more stable than PTL in vivo, was recently developed, and this study aimed to decipher its suitability as therapeutic tool for IBD and IBD-associated diseases. Similar to PTL, MCL inhibited NF-κB activation and subsequent pro-inflammatory pathways activation in vitro. Pro-drug forms of both compounds inhibited the DSS-induced colitis when administrated intraperitoneally or encapsulated in a polysaccharide gel designed to release drugs in the colon. Interestingly, MCL was found to attenuate carcinogenesis in AOM/DSS-induced CRC, thus providing new candidate for the treatment of inflammatory bowel disease and CRC.


Asunto(s)
Colitis/prevención & control , Neoplasias Colorrectales/prevención & control , FN-kappa B/antagonistas & inhibidores , Sesquiterpenos de Guayano/farmacología , Animales , Secuencia de Bases , Western Blotting , Línea Celular , Colitis/complicaciones , Neoplasias Colorrectales/complicaciones , Cartilla de ADN , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Lipopolisacáridos/farmacología , Espectroscopía de Resonancia Magnética , Ratones , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa
11.
Biochem Biophys Res Commun ; 446(3): 656-62, 2014 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-24333430

RESUMEN

Liver X receptors LXRα (NR1H3) and LXRß (NR1H2) are transcription factors belonging to the nuclear receptor superfamily, activated by specific oxysterols, oxidized derivatives of cholesterol. These receptors are involved in the regulation of testis physiology. Lxr-deficient mice pointed to the physiological roles of these nuclear receptors in steroid synthesis, lipid homeostasis and germ cell apoptosis and proliferation. Diethylstilbestrol (DES) is a synthetic estrogen considered as an endocrine disruptor that affects the functions of the testis. Various lines of evidences have made a clear link between estrogens, their nuclear receptors ERα (NR3A1) and ERß (NR3A2), and Lxrα/ß. As LXR activity could also be regulated by the nuclear receptor small heterodimer partner (SHP, NR0A2) and DES could act through SHP, we wondered whether LXR could be targeted by estrogen-like endocrine disruptors such as DES. For that purpose, wild-type and Lxr-deficient mice were daily treated with 0.75 µg DES from days 1 to 5 after birth. The effects of DES were investigated at 10 or 45 days of age. We demonstrated that DES induced a decrease of the body mass at 10 days only in the Lxr-deficient mice suggesting a protective effect of Lxr. We defined three categories of DES-target genes in testis: those whose accumulation is independent of Lxr; those whose accumulation is enhanced by the lack of both Lxrα/ß; those whose accumulation is repressed by the absence of Lxrα/ß. Lipid accumulation is also modified by neonatal DES injection. Lxr-deficient mice present different lipid profiles, demonstrating that DES could have its effects in part due to Lxrα/ß. Altogether, our study shows that both nuclear receptors Lxrα and Lxrß are not only basally important for testicular physiology but could also have a preventive effect against estrogen-like endocrine disruptors.


Asunto(s)
Dietilestilbestrol/toxicidad , Receptores Nucleares Huérfanos/genética , Testículo/efectos de los fármacos , Animales , Animales Recién Nacidos , Apoptosis/efectos de los fármacos , Apoptosis/genética , Peso Corporal/efectos de los fármacos , Dietilestilbestrol/metabolismo , Células Intersticiales del Testículo/efectos de los fármacos , Células Intersticiales del Testículo/patología , Metabolismo de los Lípidos/efectos de los fármacos , Metabolismo de los Lípidos/genética , Receptores X del Hígado , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Receptores Nucleares Huérfanos/metabolismo , Células de Sertoli/efectos de los fármacos , Células de Sertoli/patología , Testículo/patología
12.
Am J Pathol ; 182(5): 1617-28, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23499375

RESUMEN

Inflammatory bowel diseases are characterized by epithelial barrier disruption and alterations in immune regulation. Ste20-like proline/alanine-rich kinase (SPAK) plays a role in intestinal inflammation, but the underlying mechanisms need to be defined. Herein, SPAK knockout (KO) C57BL/6 mice exhibited significant increases in intestinal transepithelial resistance, a marked decrease in paracellular permeability to fluorescence isothiocyanate-dextran, and altered apical side tight junction sodium ion selectivity, compared with wild-type mice. Furthermore, the expression of junction protein, claudin-2, decreased. In contrast, expressions of occludin, E-cadherin, ß-catenin, and claudin-5 increased significantly, whereas no obvious change of claudin-1, claudin-4, zonula occludens protein 1, and zonula occludens protein 2 expressions was observed. In murine models of colitis induced by dextran sulfate sodium and trinitrobenzene sulfuric acid, KO mice were more tolerant than wild-type mice, as demonstrated by colonoscopy features, histological characteristics, and myeloperoxidase activities. Consistent with these findings, KO mice showed increased IL-10 levels and decreased proinflammatory cytokine secretion, ameliorated bacterial translocation on treatment with dextran sulfate sodium, and regulation of with no lysine (WNK) kinase activity. Together, these features may reduce epithelial permeability. In conclusion, SPAK deficiency increases intestinal innate immune homeostasis, which is important for control or attenuation of pathological responses in inflammatory bowel diseases.


Asunto(s)
Técnicas de Inactivación de Genes , Inflamación/enzimología , Inflamación/prevención & control , Intestinos/enzimología , Intestinos/patología , Proteínas Serina-Treonina Quinasas/deficiencia , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Bacterias/metabolismo , Colitis/patología , Citocinas/metabolismo , Sulfato de Dextran , Células Epiteliales/patología , Inflamación/patología , Lisina/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal , Proteínas de Uniones Estrechas/metabolismo
13.
Lancet Diabetes Endocrinol ; 12(5): 339-349, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38663950

RESUMEN

BACKGROUND: Experimental studies have suggested potential detrimental effects of emulsifiers on gut microbiota, inflammation, and metabolic perturbations. We aimed to investigate the associations between exposures to food additive emulsifiers and the risk of type 2 diabetes in a large prospective cohort of French adults. METHODS: We analysed data from 104 139 adults enrolled in the French NutriNet-Santé prospective cohort study from May 1, 2009, to April 26, 2023; 82 456 (79·2%) were female and the mean age was 42·7 years (SD 14·5). Dietary intakes were assessed with three 24 h dietary records collected over three non-consecutive days, every 6 months. Exposure to additive emulsifiers was evaluated through multiple food composition databases and ad-hoc laboratory assays. Associations between cumulative time-dependent exposures to food additive emulsifiers and the risk of type 2 diabetes were characterised with multivariable proportional hazards Cox models adjusted for known risk factors. The NutriNet-Santé study is registered at ClinicalTrials.gov (NCT03335644). FINDINGS: Of 104 139 participants, 1056 were diagnosed with type 2 diabetes during follow-up (mean follow-up duration 6·8 years [SD 3·7]). Intakes of the following emulsifiers were associated with an increased risk of type 2 diabetes: total carrageenans (hazard ratio [HR] 1·03 [95% CI 1·01-1·05] per increment of 100 mg per day, p<0·0001), carrageenans gum (E407; HR 1·03 [1·01-1·05] per increment of 100 mg per day, p<0·0001), tripotassium phosphate (E340; HR 1·15 [1·02-1·31] per increment of 500 mg per day, p=0·023), acetyl tartaric acid esters of monoglycerides and diglycerides of fatty acids (E472e; HR 1·04 [1·00-1·08] per increment of 100 mg per day, p=0·042), sodium citrate (E331; HR 1·04 [1·01-1·07] per increment of 500 mg per day, p=0·0080), guar gum (E412; HR 1·11 [1·06-1·17] per increment of 500 mg per day, p<0·0001), gum arabic (E414; HR 1·03 [1·01-1·05] per increment of 1000 mg per day, p=0·013), and xanthan gum (E415, HR 1·08 [1·02-1·14] per increment of 500 mg per day, p=0·013). INTERPRETATION: We found direct associations between the risk of type 2 diabetes and exposures to various food additive emulsifiers widely used in industrial foods, in a large prospective cohort of French adults. Further research is needed to prompt re-evaluation of regulations governing the use of additive emulsifiers in the food industry for better consumer protection. FUNDING: European Research Council, French National Cancer Institute, French Ministry of Health, IdEx Université de Paris, and Bettencourt-Schueller Foundation.


Asunto(s)
Diabetes Mellitus Tipo 2 , Emulsionantes , Aditivos Alimentarios , Humanos , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/inducido químicamente , Femenino , Masculino , Adulto , Estudios Prospectivos , Aditivos Alimentarios/efectos adversos , Persona de Mediana Edad , Emulsionantes/efectos adversos , Factores de Riesgo , Francia/epidemiología , Estudios de Cohortes
14.
Infect Immun ; 81(3): 923-34, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23297381

RESUMEN

CD98 is a type II transmembrane glycoprotein whose expression increases in intestinal epithelial cells (IECs) during intestinal inflammation. Enteropathogenic Escherichia coli (EPEC) is a food-borne human pathogen that attaches to IECs and injects effector proteins directly into the host cells, thus provoking an inflammatory response. In the present study, we investigated CD98 and EPEC interactions in vitro and ex vivo and examined FVB wild-type (WT) and villin-CD98 transgenic mice overexpressing human CD98 in IECs (hCD98 Tg mice) and infected with Citrobacter rodentium as an in vivo model. In vivo studies indicated that CD98 overexpression, localized to the apical domain of colonic cells, increased the attachment of C. rodentium in mouse colons and resulted in increased expression of proinflammatory markers and decreased expression of anti-inflammatory markers. The proliferative markers Ki-67 and cyclin D1 were significantly increased in the colonic tissue of C. rodentium-infected hCD98 Tg mice compared to that of WT mice. Ex vivo studies correlate with the in vivo data. Small interfering RNA (siRNA) studies with Caco2-BBE cells showed a decrease in adherence of EPEC to Caco2 cells in which CD98 expression was knocked down. In vitro surface plasmon resonance (SPR) experiments showed direct binding between recombinant hCD98 and EPEC/C. rodentium proteins. We also demonstrated that the partial extracellular loop of hCD98 was sufficient for direct binding to EPEC/C. rodentium. These findings demonstrate the importance of the extracellular loop of CD98 in the innate host defense response to intestinal infection by attaching and effacing (A/E) pathogens.


Asunto(s)
Infecciones por Enterobacteriaceae/inmunología , Proteína-1 Reguladora de Fusión/metabolismo , Inmunidad Innata , Mucosa Intestinal/metabolismo , Animales , Células CACO-2 , Citrobacter rodentium , Colon , Infecciones por Enterobacteriaceae/microbiología , Escherichia coli Enteropatógena , Células Epiteliales/inmunología , Células Epiteliales/metabolismo , Femenino , Proteína-1 Reguladora de Fusión/genética , Regulación de la Expresión Génica/inmunología , Humanos , Masculino , Ratones , Ratones Transgénicos , Peroxidasa , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos
15.
Lab Invest ; 93(8): 888-99, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23797361

RESUMEN

We and others have shown that the dipeptide cotransporter PepT1 is expressed in immune cells, including macrophages that are in close contact with the lamina propria of the small and large intestines. In the present study, we used PepT1-knockout (KO) mice to explore the role played by PepT1 in immune cells during dextran sodium sulfate (DSS)-induced colitis. DSS treatment caused less severe body weight loss, diminished rectal bleeding, and less diarrhea in PepT1-KO mice than in wild-type (WT) animals. A histological examination of colonic sections revealed that the colonic architecture was less disrupted and the extent of immune cell infiltration into the mucosa and submucosa following DSS treatment was reduced in PepT1-KO mice compared with WT animals. Consistent with these results, the DSS-induced colitis increase in colonic myeloperoxidase activity was significantly less in PepT1-KO mice than in WT littermates. The colonic levels of mRNAs encoding the inflammatory cytokines CXCL1, interleukin (IL)-6, monocyte chemotactic protein-1, IL-12, and interferon-γ were significantly lower in DSS-treated PepT1-KO mice than in DSS-treated WT animals. Colonic immune cells from WT had significantly higher level of proinflammatory cytokines then PepT1 KO. In addition, we observed that knocking down the PepT1 expression decreases chemotaxis of immune cells recruited during intestinal inflammation. Antibiotic treatment before DSS-induced colitis eliminated the differential expression of inflammatory cytokines between WT and PepT1-KO mice. In conclusion, PepT1 in immune cells regulates the secretion of proinflammatory cytokines triggered by bacteria and/or bacterial products, and thus has an important role in the induction of colitis. PepT1 may transport small bacterial products, such as muramyl dipeptide and the tripeptide L-Ala-gamma-D-Glu-meso-DAP, into macrophages. These materials may be sensed by members of the nucleotide-binding site-leucine-rich repeat family of intracellular receptors, ultimately resulting in altered homeostasis of the intestinal microbiota.


Asunto(s)
Colitis/inmunología , Expresión Génica , Inmunidad Celular/inmunología , Macrófagos/metabolismo , Simportadores/genética , Animales , Antibacterianos/farmacología , Colitis/inducido químicamente , Colitis/patología , Colon/efectos de los fármacos , Colon/enzimología , Colon/microbiología , Citocinas/genética , Citocinas/metabolismo , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Femenino , Técnicas de Silenciamiento del Gen , Homeostasis , Inmunidad Celular/efectos de los fármacos , Macrófagos/efectos de los fármacos , Macrófagos/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transportador de Péptidos 1 , Peroxidasa/metabolismo , ARN Mensajero/metabolismo , Simportadores/metabolismo
16.
Inflamm Bowel Dis ; 29(6): 986-999, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36545755

RESUMEN

Inflammatory bowel disease (IBD), which includes ulcerative colitis and Crohn's disease, is thought to develop in genetically predisposed individuals as a consequence of complex interactions between dysregulated inflammatory stimuli, immunological responses, and environmental factors. The pathogenesis of IBD has yet to be fully understood. The global increase in the incidence of IBD suggests a gap in the current understanding of the disease. The development of a new diagnostic tool for inflammatory bowel disease that is both less invasive and more cost-effective would allow for better management of this condition. MicroRNAs (miRNAs) are a class of noncoding RNAs with important roles as posttranscriptional regulators of gene expression, which has led to new insights into understanding IBD. Using techniques such as microarrays and real-time polymerase chain reactions, researchers have investigated the patterns in which patients with Crohn's disease and ulcerative colitis show alterations in the expression of miRNA in tissue, blood, and feces. These miRNAs are found to be differentially expressed in IBD and implicated in its pathogenesis through alterations in autophagy, intestinal barrier, and immune homeostasis. In this review, we discuss the miRNA expression profiles associated with IBD in tissue, peripheral blood, and feces and provide an overview of the miRNA mechanisms involved in IBD.


We review the published studies on microRNA (miRNA) expression in inflammatory bowel disease, including miRNAs extracted from blood, tissue, and stool samples. We discuss the main mechanisms of miRNA involvement in inflammatory bowel disease and their potential use as biomarkers.


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Enfermedades Inflamatorias del Intestino , MicroARNs , Humanos , MicroARNs/metabolismo , Colitis Ulcerosa/diagnóstico , Enfermedad de Crohn/diagnóstico , Enfermedades Inflamatorias del Intestino/diagnóstico , Intestinos
17.
BMJ ; 382: e076058, 2023 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-37673430

RESUMEN

OBJECTIVE: To assess the associations between exposure to food additive emulsifiers and risk of cardiovascular disease (CVD). DESIGN: Prospective cohort study. SETTING: French NutriNet-Santé study, 2009-21. PARTICIPANTS: 95 442 adults (>18 years) without prevalent CVD who completed at least three 24 hour dietary records during the first two years of follow-up. MAIN OUTCOME MEASURES: Associations between intake of food additive emulsifiers (continuous (mg/day)) and risk of CVD, coronary heart disease, and cerebrovascular disease characterised using multivariable proportional hazard Cox models to compute hazard ratios for each additional standard deviation (SD) of emulsifier intake, along with 95% confidence intervals. RESULTS: Mean age was 43.1 (SD 14.5) years, and 79.0% (n=75 390) of participants were women. During follow-up (median 7.4 years), 1995 incident CVD, 1044 coronary heart disease, and 974 cerebrovascular disease events were diagnosed. Higher intake of celluloses (E460-E468) was found to be positively associated with higher risks of CVD (hazard ratio for an increase of 1 standard deviation 1.05, 95% confidence interval 1.02 to 1.09, P=0.003) and coronary heart disease (1.07, 1.02 to 1.12, P=0.004). Specifically, higher cellulose E460 intake was linked to higher risks of CVD (1.05, 1.01 to 1.09, P=0.007) and coronary heart disease (1.07, 1.02 to 1.12, P=0.005), and higher intake of carboxymethylcellulose (E466) was associated with higher risks of CVD (1.03, 1.01 to 1.05, P=0.004) and coronary heart disease (1.04, 1.02 to 1.06, P=0.001). Additionally, higher intakes of monoglycerides and diglycerides of fatty acids (E471 and E472) were associated with higher risks of all outcomes. Among these emulsifiers, lactic ester of monoglycerides and diglycerides of fatty acids (E472b) was associated with higher risks of CVD (1.06, 1.02 to 1.10, P=0.002) and cerebrovascular disease (1.11, 1.06 to 1.16, P<0.001), and citric acid ester of monoglycerides and diglycerides of fatty acids (E472c) was associated with higher risks of CVD (1.04, 1.02 to 1.07, P=0.004) and coronary heart disease (1.06, 1.03 to 1.09, P<0.001). High intake of trisodium phosphate (E339) was associated with an increased risk of coronary heart disease (1.06, 1.00 to 1.12, P=0.03). Sensitivity analyses showed consistent associations. CONCLUSION: This study found positive associations between risk of CVD and intake of five individual and two groups of food additive emulsifiers widely used in industrial foods. TRIAL REGISTRATION: ClinicalTrials.gov NCT03335644.


Asunto(s)
Enfermedades Cardiovasculares , Adulto , Humanos , Femenino , Masculino , Enfermedades Cardiovasculares/inducido químicamente , Enfermedades Cardiovasculares/epidemiología , Aditivos Alimentarios , Diglicéridos , Monoglicéridos , Estudios Prospectivos , Celulosa , Ésteres , Ácidos Grasos
18.
Biochim Biophys Acta ; 1812(8): 974-81, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21334438

RESUMEN

Liver X receptor (LXR) α and LXRß belong to the nuclear receptor superfamily. For many years, they have been called orphan receptors, as no natural ligand was identified. In the last decade, the LXR natural ligands have been shown to be oxysterols, molecules derived from cholesterol. While these nuclear receptors have been abundantly studied for their roles in the regulation of lipid metabolism, it appears that they also present crucial activities in reproductive organs such as testis and epididymis, as well as prostate. Phenotypic analyses of mice lacking LXRs (lxr-/-) pointed out their physiological activities in the various cells and organs regulating reproductive functions. This review summarizes the impact of LXR-deficiency in male reproduction, highlighting the novel information coming from the phenotypic analyses of lxrα-/-, lxrß-/- and lxrα;ß-/- mice. This article is part of a Special Issue entitled: Translating nuclear receptor from health to disease.


Asunto(s)
Lípidos/fisiología , Receptores Nucleares Huérfanos/fisiología , Reproducción , Animales , Epidídimo/anomalías , Humanos , Receptores X del Hígado , Masculino , Ratones , Ratones Noqueados , Receptores Nucleares Huérfanos/genética , Testículo/fisiología
19.
Am J Physiol Gastrointest Liver Physiol ; 302(11): G1282-91, 2012 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-22499850

RESUMEN

The transmembrane glycoprotein CD98 is known to be involved in intestinal inflammation. In the present study, we found that CD98 overexpression in intestinal epithelial cells does not normally affect the expression of colonic (epithelial and immune cell) microRNAs (miRNAs), small noncoding RNAs that posttranscriptionally regulate a wide variety of biological processes. However, upon dextran sulfate sodium (DSS) treatment, the expression of several colonic miRNAs, but not miRNAs from other tissues such as liver and spleen, were differentially regulated in mice overexpressing CD98 in epithelial cells compared with wild-type (WT) animals. For example, the level of colonic miRNA 132 was not affected by DSS treatment in WT animals but was upregulated in mice overexpressing CD98 in intestinal epithelial cells. Other colonic miRNAs, including colonic miRNA 23a and 23b, were downregulated in WT animals after DSS treatment but not in colonic epithelial cell CD98-overexpressing mice. Interestingly, the expression of potential miRNA target genes affected intestinal epithelial cells that overexpress CD98 and cell types that did not overexpress CD98 but were in close proximity to CD98-overexpressing intestinal epithelial cells. Taken together, these observations show that the combination of an inflammatory context and intestinal epithelial cell expression of CD98 affects the regulation of miRNA expression in colonic epithelial and immune cells. This is new evidence that protein expression modulates miRNA expression and suggests the existence of regulatory crosstalk between proteins and miRNAs in diseases such as colitis.


Asunto(s)
Colitis/metabolismo , Colon/metabolismo , Proteína-1 Reguladora de Fusión/biosíntesis , Mucosa Intestinal/metabolismo , MicroARNs/metabolismo , Animales , Colitis/genética , Células Epiteliales/metabolismo , Inflamación , Ratones , MicroARNs/genética
20.
J Crohns Colitis ; 16(6): 992-1005, 2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-34918052

RESUMEN

MicroRNAs [miRNAs], small non-coding RNAs, have recently been described as crucial contributors to intestinal homeostasis. They can interact with the gut microbiota in a reciprocal manner and deeply affect host health status, leading to several disorders when unbalanced. Inflammatory bowel disease [IBD] is a chronic inflammation of the gastrointestinal tract that co-occurs with alterations of the gut microbiota, and whose aetiology remains largely unclear. On one hand, host miRNA could be playing a relevant role in IBD pathophysiology by shaping the gut microbiota. The gut microbiome, on the other hand, may regulate the expression of host miRNAs, resulting in intestinal epithelial dysfunction, altered autophagy, and immune hyperactivation. Interestingly, it has been hypothesised that their reciprocal impact may be used for therapeutic goals. This review describes the latest research and suggests mechanisms through which miRNA and intestinal microbiota, as joint actors, may participate specifically in IBD pathophysiology. Furthermore, we discuss the diagnostic power and therapeutic potential resulting from their bidirectional communication after faecal transplantation, probiotics intake, or anti-miRNAs or miRNA mimics administration. The current literature is summarised in the present work in a comprehensive manner, hoping to provide a better understanding of the miRNA-microbiota cross-talk and to facilitate their application in IBD.


Asunto(s)
Enfermedades Gastrointestinales , Microbioma Gastrointestinal , Enfermedades Inflamatorias del Intestino , MicroARNs , Probióticos , Trasplante de Microbiota Fecal , Microbioma Gastrointestinal/fisiología , Humanos , Enfermedades Inflamatorias del Intestino/diagnóstico , MicroARNs/genética , Probióticos/uso terapéutico
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