Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
1.
Int J Obes (Lond) ; 46(7): 1311-1318, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35383269

RESUMEN

INTRODUCTION: Glucagon-like peptide-1 receptor agonists (GLP-1ra) are increasingly used in treating type 2 diabetes and obesity. Exendin-4 (Ex-4), a long acting GLP-1ra, was previously reported to decrease oxidative stress in hepatocytes, adipocytes and skeletal muscle cells in obese nondiabetic fa/fa Zucker rats (ZFR), thereby improving insulin resistance. AIM: We aimed first to identify Ex-4-induced changes in the transcriptome of skeletal muscle cells in ZFR. RESULTS: Ontology analysis of differentially expressed genes (DEGs) in ZFR versus lean animals (LR) showed that the extracellular matrix (ECM) is the first most affected cellular compartment, followed by myofibrils and endoplasmic reticulum (ER). Interestingly, among 15 genes regulated in ZFR versus LR, 14 of them were inversely regulated by Ex-4, as further confirmed by RT-qPCR. Picro-Sirius red histological staining showed that decreased ECM fiber area in ZFR is partially restored by Ex-4. Ontology analysis of the myofibril compartment revealed that decreased muscle contractile function in ZFR is partially restored by Ex-4, as confirmed by Phalloidin histological staining that showed a partial restoration by Ex-4 of altered contractile apparatus in ZFR. Ontology analysis of ER DEGs in ZFR versus LR showed that some of them are related to the AMP-activated protein kinase (AMPK) signaling pathway. Phosphorylated AMPK levels were strongly increased in Ex-4-treated ZFR. CONCLUSION: Altogether, our results suggest that GLP-1ra strongly restructure ECM and reinforce contractile capabilities in ZFR, while optimizing the cellular metabolism through AMPK.


Asunto(s)
Diabetes Mellitus Tipo 2 , Incretinas , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Diabetes Mellitus Tipo 2/metabolismo , Exenatida/farmacología , Incretinas/metabolismo , Incretinas/farmacología , Insulina/metabolismo , Músculo Esquelético/metabolismo , Obesidad/metabolismo , Ratas , Ratas Zucker , Transcriptoma/genética
2.
Int J Mol Sci ; 21(11)2020 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-32486504

RESUMEN

Breast cancer remains a major concern and its physiopathology is influenced by iodine deficiency (ID) and radiation exposure. Since radiation and ID can separately induce oxidative stress (OS) and microvascular responses in breast, their combination could additively increase these responses. Therefore, ID was induced in MCF7 and MCF12A breast cell lines by medium change. Cells were then X-irradiated with doses of 0.05, 0.1, or 3 Gy. In MCF12A cells, both ID and radiation (0.1 and 3 Gy) increased OS and vascular endothelial growth factor (VEGF) expression, with an additive effect when the highest dose was combined with ID. However, in MCF7 cells no additive effect was observed. VEGF mRNA up-regulation was reactive oxygen species (ROS)-dependent, involving radiation-induced mitochondrial ROS. Results on total VEGF mRNA hold true for the pro-angiogenic isoform VEGF165 mRNA, but the treatments did not modulate the anti-angiogenic isoform VEGF165b. Radiation-induced antioxidant response was differentially regulated upon ID in both cell lines. Thus, radiation response is modulated according to iodine status and cell type and can lead to additive effects on ROS and VEGF. As these are often involved in cancer initiation and progression, we believe that iodine status should be taken into account in radiation prevention policies.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/radioterapia , Mama/metabolismo , Mama/efectos de la radiación , Yodo/deficiencia , Estrés Oxidativo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Antioxidantes/metabolismo , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Células MCF-7 , Neovascularización Patológica , ARN Mensajero/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Regulación hacia Arriba
3.
Soins Gerontol ; 24(135): 39-42, 2019.
Artículo en Francés | MEDLINE | ID: mdl-30765087

RESUMEN

Heart failure, a serious and progressive disease, mainly affects the elderly. The Vendée coastline attracts high numbers of retired people to the region. Faced with this observation, Vendée departmental hospital deemed it necessary to put in place a monitoring unit providing adapted care in order to reduce the rate of mortality and rehospitalisation. The implementation of the Return Home programme has had a positive impact on the optimised care management of patients.


Asunto(s)
Insuficiencia Cardíaca/terapia , Servicios de Atención a Domicilio Provisto por Hospital/organización & administración , Anciano , Humanos , Evaluación de Programas y Proyectos de Salud
4.
Am J Physiol Cell Physiol ; 315(4): C544-C557, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30020826

RESUMEN

Iodine deficiency (ID), which affects almost two billion people worldwide, is associated with breast pathologies such as fibrosis in human and induces breast atypia in animal models. Because ID induces vascular activation in the thyroid, another iodide-uptaking organ, and as breast is also sensitive to ID, we aimed to characterize ID-induced effects on the breast microvasculature in vivo and in two different breast cell lines in vitro. Virgin and lactating NMRI mice received an iodide-deficient diet and a Na+/I- symporter inhibitor for 1 to 20 days. Some virgin mice were treated with vascular endothelial growth factor A (VEGF) or VEGF receptor inhibitors. In vitro, ID was induced in MCF7 and MCF12A cells by replacing the iodide-containing medium by an iodide-deficient medium. In vivo, VEGF expression was increased following ID in mammary tissues. Consequently, ID induced a transient increase in mammary gland blood flow, measured after anesthesia, in virgin and lactating mice, which was repressed by VEGF or VEGF receptor inhibitors. In MCF7 cells, ID induced a transient increase in reactive oxygen species, followed by an increase in hypoxia-inducible factor-1α (HIF-1α) protein and VEGF mRNA expression. Antioxidant N-acetylcysteine and mammalian target of rapamycin (mTOR) inhibitor blocked ID-induced HIF-1α protein increase and VEGF transcription. However, mTOR activity was not inhibited by N-acetylcysteine. Similar responses were observed in MCF12A cells. These data indicate that ID activates the canonical VEGF pathway and mTOR in breast tissues, which provides new insights to better understand the correlation between ID, vascular activation, and breast pathologies.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Yodo/deficiencia , Glándulas Mamarias Humanas/metabolismo , Microvasos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Acetilcisteína/metabolismo , Animales , Antioxidantes/metabolismo , Mama/metabolismo , Línea Celular Tumoral , Femenino , Humanos , Lactancia/metabolismo , Células MCF-7 , Glándulas Mamarias Animales/metabolismo , Ratones , Receptores de Factores de Crecimiento Endotelial Vascular/metabolismo , Transducción de Señal/fisiología
5.
Rev Infirm ; 67(240): 35-37, 2018 Apr.
Artículo en Francés | MEDLINE | ID: mdl-29609791

RESUMEN

Heart failure is a serious condition which affects mainly elderly people. In the Vendée region, where many people choose to retire, hospital teams have noticed an increase in hospitalisations for heart failure. To optimise the management of these patients, a follow-up service was set up in July 2016 comprising a PRADO programme specifically supporting the return home of patients with heart failure.


Asunto(s)
Continuidad de la Atención al Paciente/organización & administración , Insuficiencia Cardíaca/terapia , Servicios de Atención a Domicilio Provisto por Hospital/organización & administración , Francia/epidemiología , Insuficiencia Cardíaca/epidemiología , Hospitalización , Humanos , Educación del Paciente como Asunto
6.
Evol Appl ; 17(3): e13670, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38468711

RESUMEN

Since the emergence of a transmissible cancer, devil facial tumour disease (DFT1), in the 1980s, wild Tasmanian devil populations have been in decline. In 2016, a second, independently evolved transmissible cancer (DFT2) was discovered raising concerns for survival of the host species. Here, we applied experimental and modelling frameworks to examine competition dynamics between the two transmissible cancers in vitro. Using representative cell lines for DFT1 and DFT2, we have found that in monoculture, DFT2 grows twice as fast as DFT1 but reaches lower maximum cell densities. Using co-cultures, we demonstrate that DFT2 outcompetes DFT1: the number of DFT1 cells decreasing over time, never reaching exponential growth. This phenomenon could not be replicated when cells were grown separated by a semi-permeable membrane, consistent with exertion of mechanical stress on DFT1 cells by DFT2. A logistic model and a Lotka-Volterra competition model were used to interrogate monoculture and co-culture growth curves, respectively, suggesting DFT2 is a better competitor than DFT1, but also showing that competition outcomes might depend on the initial number of cells, at least in the laboratory. We provide theories how the in vitro results could be translated to observations in the wild and propose that these results may indicate that although DFT2 is currently in a smaller geographic area than DFT1, it could have the potential to outcompete DFT1. Furthermore, we provide a framework for improving the parameterization of epidemiological models applied to these cancer lineages, which will inform future disease management.

7.
touchREV Endocrinol ; 19(1): 16-24, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37313236

RESUMEN

From an epidemiological and pathophysiological point of view, Alzheimer's disease (AD) and type 2 diabetes (T2DM) should be considered 'sister' diseases. T2DM significantly increases the risk of developing AD, and the mechanisms of neuronal degeneration themselves worsen peripheral glucose metabolism in multiple ways. The pathophysiological links between the two diseases, particularly cerebral insulin resistance, which causes neuronal degeneration, are so close that AD is sometimes referred to as 'type 3 diabetes'. Although the latest news on the therapeutic front for AD is encouraging, no treatment has been shown to halt disease progression permanently. At best, the treatments slow down the progression; at worst, they are inactive, or cause worrying side effects, preventing their use on a larger scale. Therefore, it appears logical that optimizing the metabolic milieu through preventive or curative measures can also slow down the cerebral degeneration that characterizes AD. Among the different classes of hypoglycaemic drugs, glucagon-like peptide 1 receptor agonists, which are widely used in the treatment of T2DM, were shown to slow down, or even prevent, neuronal degeneration. Data from animal, preclinical, clinical phase II, cohort and large cardiovascular outcomes studies are encouraging. Of course, randomized clinical phase III studies, which are on-going, will be essential to verify this hypothesis. Thus, for once, there is hope for slowing down the neurodegenerative processes associated with diabetes, and that hope is the focus of this review.

8.
Environ Int ; 181: 108299, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37951015

RESUMEN

Paracetamol/acetaminophen (N-acetyl-p-aminophenol, APAP) is a top selling analgesic used in more than 600 prescription and non-prescription pharmaceuticals. To study efficiently some of the potential undesirable effects associated with increasing APAP consumption (e.g., developmental disorders, drug-induced liver injury), there is a need to improve current APAP biomonitoring methods that are limited by APAP short half-life. Here, we demonstrate using high-resolution mass spectrometry (HRMS) in several human studies that APAP thiomethyl metabolite conjugates (S-methyl-3-thioacetaminophen sulfate and S-methyl-3-thioacetaminophen sulphoxide sulfate) are stable biomarkers with delayed excretion rates compared to conventional APAP metabolites, that could provide a more reliable history of APAP ingestion in epidemiological studies. We also show that these biomarkers could serve as relevant clinical markers to diagnose APAP acute intoxication in overdosed patients, when free APAP have nearly disappeared from blood. Using in vitro liver models (HepaRG cells and primary human hepatocytes), we then confirm that these thiomethyl metabolites are directly linked to the toxic N-acetyl-p-benzoquinone imine (NAPQI) elimination, and produced via an overlooked pathway called the thiomethyl shunt pathway. Further studies will be needed to determine whether the production of the reactive hepatotoxic NAPQI metabolites is currently underestimated in human. Nevertheless, these biomarkers could already serve to improve APAP human biomonitoring, and investigate, for instance, inter-individual variability in NAPQI production to study underlying causes involved in APAP-induced hepatotoxicity. Overall, our findings demonstrate the potential of exposomics-based HRMS approach to advance towards a better precision for human biomonitoring.


Asunto(s)
Acetaminofén , Monitoreo Biológico , Humanos , Acetaminofén/toxicidad , Acetaminofén/química , Acetaminofén/metabolismo , Espectrometría de Masas , Hígado , Biomarcadores/metabolismo , Sulfatos/metabolismo
9.
Sci Rep ; 12(1): 20066, 2022 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-36414712

RESUMEN

Systematic reviews and meta-analyses have been proposed as an approach to synthesize the literature and counteract the lack of power of small preclinical studies. We aimed to evaluate (1) the methodology of these reviews, (2) the methodological quality of the studies they included and (3) whether study methodological characteristics affect effect size. We searched MEDLINE to retrieve 212 systematic reviews with meta-analyses of preclinical studies published from January, 2018 to March, 2020. Less than 15% explored the grey literature. Selection, data extraction and risk of bias assessment were performed in duplicate in less than two thirds of reviews. Most of them assessed the methodological quality of included studies and reported the meta-analysis model. The risk of bias of included studies was mostly rated unclear. In meta-epidemiological analysis, none of the study methodological characteristics was associated with effect size. The methodological characteristics of systematic reviews with meta-analyses of recently published preclinical studies seem to have improved as compared with previous assessments, but the methodological quality of included studies remains poor, thus limiting the validity of their results. Our meta-epidemiological analysis did not show any evidence of a potential association between methodological characteristics of included studies and effect size.


Asunto(s)
Epidemiología , Revisiones Sistemáticas como Asunto , Sesgo
10.
Pathogens ; 11(2)2022 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-35215185

RESUMEN

Although the true prevalence of transmissible cancers is not known, these atypical malignancies are likely rare in the wild. The reasons behind this rarity are only partially understood, but the "Perfect Storm hypothesis" suggests that transmissible cancers are infrequent because a precise confluence of tumor and host traits is required for their emergence. This explanation is plausible as transmissible cancers, like all emerging pathogens, will need specific biotic and abiotic conditions to be able to not only emerge, but to spread to detectable levels. Because those conditions would be rarely met, transmissible cancers would rarely spread, and thus most of the time disappear, even though they would regularly appear. Thus, further research is needed to identify the most important factors that can facilitate or block the emergence of transmissible cancers and influence their evolution. Such investigations are particularly relevant given that human activities are increasingly encroaching into wild areas, altering ecosystems and their processes, which can influence the conditions needed for the emergence and spread of transmissible cell lines.

11.
Am J Pathol ; 176(3): 1355-63, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20093493

RESUMEN

Goiter is associated with increased oxidative stress (OS). We studied the effects of an anti-inflammatory agent, 15 deoxy-Delta12,14-prostaglandin J2 (15dPGJ2) and an antioxidant, N-acetylcysteine (NAC), on OS, thyroid function, and goiter expansion in a model of goiter induced by propylthiouracil (PTU) or perchlorate. OS was assessed by the immunodetection of 4-hydroxynonenal, thyroid function by measuring thyroxin (T4) and thyrotropin (TSH) plasma levels and detecting T4-rich thyroglobulin (Tg-I), and goiter expansion by weighing the thyroids and measuring cell proliferation (PCNA and cyclin D1 immunodetection). In both PTU and perchlorate-induced goiters, OS, TSH plasma levels, thyroid weight, and cell proliferation were strongly enhanced, whereas Tg-I expression was negative. All these parameters were reversed by NAC and 15dPGJ2 in PTU-goiters. In perchlorate-goiters, TSH plasma levels remained elevated and Tg-I-negative after NAC or 15dPGJ2 treatment. OS was reduced by NAC, but not by 15dPGJ2. In addition, NAC reduced PCNA and cyclin D1 immunostainings, as well as thyroid weight, whereas 15dPGJ2 influenced neither thyroid weight nor cell proliferation. In conclusion, NAC and 15dPGJ2 overcome PTU- but not perchlorate-induced effects. The retrieval of hormonal synthesis may result from direct chemical interactions between PTU and NAC/15dPGJ2. Although 15dPGJ2 has no effect in perchlorate-goiters, the reduction of OS by NAC is associated with altered goiter development, making OS a required condition for the growth of the thyroid gland.


Asunto(s)
Estrés Oxidativo , Glándula Tiroides/patología , Acetilcisteína/farmacología , Animales , Núcleo Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Ciclina D1/metabolismo , Femenino , Bocio/sangre , Bocio/patología , Tamaño de los Órganos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Percloratos , Peroxirredoxinas/metabolismo , Antígeno Nuclear de Célula en Proliferación/metabolismo , Propiltiouracilo , Prostaglandina D2/análogos & derivados , Prostaglandina D2/farmacología , Ratas , Ratas Wistar , Glándula Tiroides/efectos de los fármacos , Tiroxina/sangre
12.
Am J Pathol ; 177(1): 219-28, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20489149

RESUMEN

Reactive oxygen species (ROS) are crucial for thyroid hormonogenesis, and their production is kept under tight control. Oxidative stress (OS) is toxic for thyrocytes in an inflammatory context. In vitro, Th1 pro-inflammatory cytokines have already been shown to decrease thyroid-specific protein expression. In the present study, OS level and its impact on thyroid function were analyzed in vitro in Th1 cytokine (interleukin [IL]-1alpha/interferon [IFN] gamma)-incubated thyrocytes (rat and human), as well as in vivo in thyroids from nonobese diabetic mice, a model of spontaneous autoimmune thyroiditis. N-acetylcysteine (NAC) and prostaglandin, 15 deoxy-(Delta12,14)-prostaglandinJ2 (15dPGJ2), were used for their antioxidant and anti-inflammatory properties, respectively. ROS production and OS were increased in IL-1alpha/IFNgamma-incubated thyrocytes and in destructive thyroiditis. In vitro, NAC not only reduced ROS production below control levels, but further decreased the expression of thyroid-specific proteins in addition to IL-1alpha/IFNgamma-inhibitory effects. Thus, besides ROS, other intracellular intermediaries likely mediate Th1 cytokine effects. In vivo, NAC and 15dPGJ2 reduced OS and the immune infiltration, thereby leading to a restoration of thyroid morphology. It is therefore likely that NAC and 15dPGJ2 mainly exert their protective effects by acting on infiltrating inflammatory cells rather than directly on thyrocytes.


Asunto(s)
Acetilcisteína/farmacología , Factores Inmunológicos/farmacología , Interferón gamma/farmacología , Interleucina-1alfa/farmacología , Prostaglandina D2/análogos & derivados , Glándula Tiroides/citología , Glándula Tiroides/patología , Tiroiditis Autoinmune/inmunología , Tiroiditis Autoinmune/patología , Animales , Células Cultivadas , Femenino , Humanos , Ratones , Ratones Endogámicos NOD , Peroxirredoxinas/metabolismo , Prostaglandina D2/farmacología , Ratas , Especies Reactivas de Oxígeno/metabolismo , Proteínas Recombinantes , Glándula Tiroides/inmunología
13.
Eur J Intern Med ; 88: 96-103, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33879385

RESUMEN

OBJECTIVES: To assess the efficacy and safety of adjuvant therapies in newly diagnosed or relapsing giant cell arteritis (GCA) in terms of relapse rate at week 52 (primary outcome) and to assess the impact of GC tapering regimen on adjuvant effectiveness. METHODS: For this systematic review and meta-analysis, we searched PubMed, EMBASE, CENTRAL, trial registries, from inception to November 2020. We included all randomized controlled trials (RCTs) and controlled prospective studies evaluating adjuvant treatments in GCA, without date or language restriction. Two reviewers independently selected studies, extracted data and assessed risk of bias. Quality of evidence was summarised with GRADE. RESULTS: Of the 680 records identified, 16 studies were included (1,068 participants) evaluating various adjuvant therapies compared to GC only. No study compared adjuvants with each other. Risk of bias was high in 5/7 trials evaluating our primary outcome. Risk of relapse at week 52 was reduced for only the anti-IL6 and IL6-receptor drug class versus the control (RR=0.45, 95%CI 0.30-0.66, I2=38%), particularly tocilizumab (RR=0.38, 95%CI 0.23-0.63, I2=42%) with a moderate quality of evidence. We found no significant interaction according to GC tapering regimen. Our meta-analysis did not show a significant benefit for methotrexate. Except for dapsone, ciclosporine and hydroxychloroquine, other adjuvants did not seem to show increased risk of adverse events. CONCLUSIONS: Tocilizumab seems to reduce the relapse rate in GCA at week 52 but the quality of evidence was moderate. No other molecule has shown efficacy. No significant interaction on relapse rate by GC tapering regimen was found. STUDY REGISTRATION: PROSPERO CRD42020172011.


Asunto(s)
Arteritis de Células Gigantes , Quimioterapia Combinada , Arteritis de Células Gigantes/tratamiento farmacológico , Glucocorticoides/uso terapéutico , Humanos , Metotrexato/uso terapéutico , Esteroides/uso terapéutico
14.
Vaccine ; 38(44): 6859-6863, 2020 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-32896468

RESUMEN

Systemic lupus erythematosus (SLE) patients are at risk for pneumococcal infection. Twenty-one consecutive SLE patients (40[25-75] years) received the sequential PCV13/PPSV23 vaccine and factors associated with long-term protection were analyzed. Immune protection, defined by an antigen-specific IgG concentration ≥1.3 µg/mL for at least 70% of 7 pneumococcal serotypes was assessed at baseline, 2, 6, 12 and 36 months defining long-term protection. Only 10 patients showed pneumococcal immune protection 36 months after vaccination. Eleven (52.4%) patients had no long-term protection with a seroconversion that never or only transiently occurred. SLE disease features, treatment received and immunological characteristics did not differ between protected and unprotected patients except for the pre-vaccination IgG2 serum levels. Serum IgG2 level >2.125 µg/ml showed a sensitivity of 100% and a specificity of 90.9% for long-term protection. Sequential pneumococcal vaccination conferred poor immune protection in SLE. Baseline IgG2 serum level identified patients able to benefit from pneumococcal vaccination.


Asunto(s)
Lupus Eritematoso Sistémico , Infecciones Neumocócicas , Anticuerpos Antibacterianos , Humanos , Inmunoglobulina G , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas , Streptococcus pneumoniae , Vacunación
15.
iScience ; 23(11): 101716, 2020 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-33241195

RESUMEN

Cellular cheating leading to cancers exists in all branches of multicellular life, favoring the evolution of adaptations to avoid or suppress malignant progression, and/or to alleviate its fitness consequences. Ecologists have until recently largely neglected the importance of cancer cells for animal ecology, presumably because they did not consider either the potential ecological or evolutionary consequences of anticancer adaptations. Here, we review the diverse ways in which the evolution of anticancer adaptations has significantly constrained several aspects of the evolutionary ecology of multicellular organisms at the cell, individual, population, species, and ecosystem levels and suggest some avenues for future research.

16.
iScience ; 23(7): 101269, 2020 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-32592998

RESUMEN

Inter-individual transmission of cancer cells represents an intriguing and unexplored host-pathogen system, with significant ecological and evolutionary ramifications. The pathogen consists of clonal malignant cell lines that spread horizontally as allografts and/or xenografts. Although only nine transmissible cancer lineages in eight host species from both terrestrial and marine environments have been investigated, they exhibit evolutionary dynamics that may provide novel insights into tumor-host interactions particularly in the formation of metastases. Here we present an overview of known transmissible cancers, discuss the necessary and sufficient conditions for cancer transmission, and provide a comprehensive review on the evolutionary dynamics between transmissible cancers and their hosts.

17.
Am J Physiol Endocrinol Metab ; 297(2): E438-51, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19435853

RESUMEN

In human thyroid, caveolin-1 is localized at the apex of thyrocytes, but its role there remains unknown. Using immunohistochemistry, (127)I imaging, transmission electron microscopy, immunogold electron microscopy, and quantification of H(2)O(2), we found that in caveolin-1 knockout mice thyroid cell homeostasis was disrupted, with evidence of oxidative stress, cell damage, and apoptosis. An even more striking phenotype was the absence of thyroglobulin and iodine in one-half of the follicular lumina and their presence in the cytosol, suggesting that the iodide organification and binding to thyroglobulin were intracellular rather than at the apical membrane/extracellular colloid interface. The latter abnormality may be secondary to the observed mislocalization of the thyroid hormone synthesis machinery (dual oxidases, thyroperoxidase) in the cytosol. Nevertheless, the overall uptake of radioiodide, its organification, and secretion as thyroid hormones were comparable to those of wild-type mice, suggesting adequate compensation by the normal TSH retrocontrol. Accordingly, the levels of free thyroxine and TSH were normal. Only the levels of free triiodothyronine showed a slight decrease in caveolin-1 knockout mice. However, when TSH levels were increased through low-iodine chow and sodium perchlorate, the induced goiter was more prominent in caveolin-1 knockout mice. We conclude that caveolin-1 plays a role in proper thyroid hormone synthesis as well as in cell number homeostasis. Our study demonstrates for the first time a physiological function of caveolin-1 in the thyroid gland. Because the expression and subcellular localization of caveolin-1 were similar between normal human and murine thyroids, our findings in caveolin-1 knockout mice may have direct relevance to the human counterpart.


Asunto(s)
Caveolina 1/fisiología , Homeostasis/genética , Glándula Tiroides/fisiología , Hormonas Tiroideas/biosíntesis , Animales , Apoptosis/genética , Células CHO , Caveolina 1/genética , Caveolina 1/metabolismo , Membrana Celular/metabolismo , Cricetinae , Cricetulus , Halogenación/genética , Peróxido de Hidrógeno/metabolismo , Ratones , Ratones Noqueados , Estrés Oxidativo/genética , Fenotipo , Glándula Tiroides/anomalías , Glándula Tiroides/citología , Glándula Tiroides/metabolismo
18.
Endocrinology ; 149(4): 1534-42, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18187547

RESUMEN

Hypothyroidism, together with glandular atrophy, is the usual outcome of destructive autoimmune thyroiditis. The impairment in the thyroid function results either from cell destruction or from Th1 cytokine-induced alteration in hormonogenesis. Here, we investigated the impact of the local immune context on the thyroid function. We used two rat thyroid cell lines (PCCL3 and FRTL-5) and human thyrocytes incubated with IL-1alpha/interferon (IFN) gamma together with IL-4, a Th2 cytokine, or with TGF-beta, or IL-10, two Th3 cytokines. We first observed that IL-4 totally blocked IL-1alpha/interferon gamma-induced alteration in dual oxidase and thyroperoxidase expression, and in thyroglobulin secretion. By contrast, TGF-beta and IL-10 had no such effect. They rather repressed thyrocyte function as do Th1 cytokines. In addition, IL-4 blocked IL-10-induced repression of thyrocyte function, but not that induced by TGF-beta. In conclusion, Th1 cytokine- and IL-10-induced local inhibitory actions on thyroid function can be totally overturned by Th2 cytokines. These data provide new clues about the influence of the immune context on thyrocyte function.


Asunto(s)
Citocinas/farmacología , Flavoproteínas/genética , Regulación de la Expresión Génica/efectos de los fármacos , Yoduro Peroxidasa/genética , NADPH Oxidasas/genética , Linfocitos T Reguladores/inmunología , Células TH1/inmunología , Células Th2/inmunología , Tiroglobulina/metabolismo , Glándula Tiroides/metabolismo , Animales , Células Cultivadas , Oxidasas Duales , Humanos , Interferón gamma/farmacología , Interleucina-1/farmacología , Interleucina-10/farmacología , Interleucina-4/farmacología , Ratas , Glándula Tiroides/citología , Factor de Crecimiento Transformador beta/farmacología
19.
Endocrinology ; 149(1): 424-33, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17884933

RESUMEN

In basal conditions, thyroid epithelial cells produce moderate amounts of reactive oxygen species (ROS) that are physiologically required for thyroid hormone synthesis. They are not necessarily toxic because they are continuously detoxified either in the process of hormone synthesis or by endogenous antioxidant systems. Using a rat model of goiter formation and iodine-induced involution, we found that compared with control thyroids, the oxidative stress, assessed by the detection of 4-hydroxynonenal, was strongly enhanced both in hyperplastic and involuting glands. The level of antioxidant defenses (glutathione peroxidases and peroxiredoxins) was also up-regulated in both groups, although somewhat less in the latter. Of note, increased oxidative stress came along with an inflammatory reaction, but only in involuting glands, suggesting that although antioxidant systems can adequately buffer a heavy load of ROS in goiter, it is not necessarily the case in involuting glands. The effects of 15-deoxy-Delta(12,14)-prostaglandin J2 (15dPGJ2), an endogenous ligand of peroxisome proliferated-activated receptor gamma (PPARgamma) with antiinflammatory properties, were then investigated in involuting glands. This drug strongly reduced both 4-hydroxynonenal staining and the inflammatory reaction, indicating that it can block iodine-induced cytotoxicity. When experiments were carried out with the PPARgamma antagonist, bisphenol A diglycidyl ether, 15dPGJ2-induced effects remained unchanged, suggesting that these effects were not mediated by PPARgamma. In conclusion, thyroid epithelial cells are well adapted to endogenously produced ROS in basal and goitrous conditions. In iodine-induced goiter involution, the increased oxidative stress is accompanied by inflammation that can be blocked by 15dPGJ2 through PPARgamma-independent protective effects.


Asunto(s)
Bocio/etiología , Bocio/patología , Yodo/metabolismo , Estrés Oxidativo/fisiología , Glándula Tiroides/metabolismo , Glándula Tiroides/fisiología , Algoritmos , Animales , Antioxidantes/metabolismo , Compuestos de Bencidrilo , Carcinógenos/farmacología , Citoprotección/efectos de los fármacos , Progresión de la Enfermedad , Compuestos Epoxi/farmacología , Femenino , Glutatión Peroxidasa/metabolismo , Bocio/tratamiento farmacológico , Bocio/metabolismo , Yodo/farmacología , Yodo/uso terapéutico , Modelos Biológicos , Estrés Oxidativo/efectos de los fármacos , PPAR gamma/metabolismo , PPAR gamma/fisiología , Peroxirredoxinas/metabolismo , Prostaglandina D2/análogos & derivados , Prostaglandina D2/farmacología , Ratas , Ratas Wistar , Inducción de Remisión , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/patología , Tiroiditis/inducido químicamente , Tiroiditis/patología
20.
Endocrinol Diabetes Metab ; 1(3): e00023, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30815557

RESUMEN

AIMS: Using the novel FreeStyle Libre (FSL), glucose monitoring (FGM) system becomes increasingly popular among people with type 1 diabetes (T1D) and is associated with less and shorter hypoglycaemic events without deterioration of HbA1c. There are not yet data reporting the impact of FGM in people with T1D in real-life conditions. We sought of evaluating the tolerance, the acceptance and the efficacy of the FGM system in routine medical practice. METHODS: This 12-month observational study included 120 individuals with T1D evaluated every 3 months. After having been instructed about FGM utilization, participants were trained to optimize the glycaemic control. RESULTS: Participants stopped immediately of measuring capillary blood glucose (2.88 ± 0.12 per day) (mean ± SEM) after having received the first FSL device and the number of scans per day increased up to 8.87 ± 0.58 per day. HbA1c levels decreased from 8.51% ± 0.14% at baseline to 7.77% ± 0.09% after 3 months to slightly increase to 7.92% ± 0.09% at 12 months, in correlation with the number of scans per day. The number (but not the duration) of hypoglycaemic events slightly increased from 16.9 ± 1.44 per month at baseline to 24.0 ± 2.91 per month at 12 months, after reaching a peak of 26.4 ± 2.31 per month at 6 months. They were correlated with improved HbA1c. CONCLUSION: Our study shows that using the FGM system improves HbA1c levels in people with T1D along with a moderate increase in the number of mild hypoglycaemic events. The new FGM system facilitates the therapeutic empowerment of people with T1D, but in a context of structured education.

SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda