Effects of Thyroid hormone on Cardiomyocytes and on Glioma differentiation and proliferation

The action of thyroid hormone (TH) on cell growth, differentiation and survival during development may be of therapeutic relevance. The present study investigated the potential effects of long-term TH treatment on cardiomyocytes and on glioma tumour cell lines. This study employed neonatal cardiomyocytes, 1321N1 cell line, an astrocytoma grade II, and U87MG, a glioblastoma grade IV. Cells were exposed for 2 and 4 days in culture medium deprived of T3 (non-treated cells) and in a medium containing either 1 nM T3 (at near physiological range) or 500 nM T3 (supraphysiological). From the initial study on cardiomyocytes, the results show that phenylephryne (PE) can induce cell growth and this effect was mediated by T3. For the glioma cell lines the results show that T3 at 1 nM can promote cell re-differentiation in both cell lines. However, T3 had a preferential effect on suppressing cell proliferation only in the high grade glioma cell line. Thus, in 1321N1 cell line, T3 increased cell proliferation (2 days) which declined thereafter (4 days) without having any effect on cell survival. In U87MG cell line, T3 resulted in marked suppression of cell proliferation without increasing cell injury. At the molecular level, a 2.9 fold increase in the expression of TRα1 receptor was observed in U87MG cells as compared to 1321N1, p<0.05. TRβ1 receptor was undetectable in both cell lines. These changes corresponded to a distinct pattern of growth signalling activation induced by T3 treatment. The results also show that T3 had no significant effect on ERK activation in both cell lines, but significantly (p<0.05) increased phospho-Akt levels in 1321N1 cell line. At higher dose, T3 also induced cell differentiation in both cell lines and suppressed proliferation while increased cell injury in U87MG cells. It can be concluded from these results that T3 can re-differentiate glioma tumour cells. However, the effect of T3 on cell proliferation appears to be dependent on the type of tumour cell line with aggressive tumours to be more sensitive to thyroid hormone treatment. TRα1 receptor may, at least in part, be implicated in this response

Early leukocyte activation receptor CD69: a novel player in the maintenance of the Th17/Treg balance in peritoneal fibrosis

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 09-03-2015CD69 is induced after activation of leukocytes at inflammatory sites. Mice lacking CD69 develop exacerbated forms of inflammatory diseases, which are largely mediated by misbalanced responses of T helper (Th) 17 cells and regulatory T cells (Tregs), indicating that CD69 modulates Th17 differentiation and plays a role in regulatory T cell function. However, the pathophysiological role of CD69 in fibrotic diseases remains largely unknown. Renal patients subjected to peritoneal dialysis (PD) develop progressive peritoneal fibrosis, which may lead to technique failure. Herein, we observed that infiltrating T lymphocytes of PD patients expressed high levels of CD69. Thus, we explored the role of CD69 in fibro-proliferative responses by analyzing a model of peritoneal fibrosis induced by dialysis fluid exposure in WT and CD69-deficient mice. CD69–/– mice showed enhanced peritoneal thickness and myofibroblasts accumulation as well as higher incidence of mesothelial to mesenchymal transition (MMT). In parallel, CD69–/– mice showed exacerbated inflammatory infiltrates, a marked increase of Th17 cells and IL-17 cytokine and reduction of Tregs. Transplantation of a mixture of bone marrows from CD69–/– and Rag2–/– mice into WT recipients reproduced the severity of the disease upon PD fluid exposure, demonstrating that CD69 exerts its function within the lymphocyte compartment. Blockade of IL-17 in CD69–/– mice reduced Th17 response and inflammatory infiltrates and resulted in decreased peritoneal fibrosis induced by PD fluid. Conversely, blockade of CD69 in WT mice mimicked the exacerbated response of CD69–/– mice to PD fluid exposure. Our findings indicate that CD69 modulates Th17-mediated inflammatory responses in the peritoneal cavity and negatively regulates peritoneal fibrosis induced by dialysis fluid exposure.El receptor CD69 se induce tras la activación leucocitaria en los infiltrados inflamatorios. Los ratones deficientes en CD69 desarrollan formas exacerbadas de enfermedades inflamatorias que están mediadas por una respuesta desbalanceada entre linfocitos T “helper” Th17 y células T reguladora (Tregs), lo que indica que CD69 modula la diferenciación de Th17 y que juega un papel en la función de las células Tregs. Sin embargo, el papel fisio-patológico de CD69 en enfermedades fibróticas es desconocido. Los pacientes renales sometidos a diálisis peritoneal (DP) desarrollan fibrosis peritoneal progresiva, la cual puede dar lugar al fallo de la técnica. En este estudio, hemos observado altos niveles de expresión de CD69 en los linfocitos infiltrantes de los pacientes en DP. Por lo tanto, decidimos explorar el papel de CD69 en la respuesta fibroproliferativa mediante el análisis de un modelo de fibrosis peritoneal inducido por líquidos de diálisis en ratones silvestres y en ratones deficientes para CD69. Los ratones CD69–/– mostraron un mayor engrosamiento peritoneal y una mayor acumulación de miofibroblastos, así como una mayor incidencia de transición mesotelio mesenquimal (TMM). En paralelo, los ratones CD69–/– mostraron infiltrados inflamatorios exacerbados, un marcado aumento de células Th17 y de la citoquina IL-17 y una reducción de células Tregs. El trasplante de una mezcla de medulas óseas procedentes de ratones CD69–/– y Rag2–/– en ratones silvestres reprodujo la severidad de la enfermedad inducida por la exposición al líquido de DP, demostrando asi que CD69 ejerce su función en el compartimento de linfocitos. El bloqueo de IL- 17 en ratones CD69–/– redujo la respuesta Th17 y el infiltrado inflamatorio y dio lugar a una reducción de la fibrosis inducida por el líquido de DP. Por otro lado, el bloqueo de CD69 en ratones silvestres mimetizó la respuesta exacerbada a la exposición del liquido de diálisis de los ratones CD69–/–. Nuestros resultados indican que CD69 modula la respuesta inflamatoria mediada por Th17 en la cavidad peritoneal y regula negativamente la fibrosis peritoneal inducida por la exposición a liquido de diálisi

Cell-Type-Dependent Thyroid Hormone Effects on Glioma Tumor Cell Lines

Purpose. The present study investigated the potential effects of long-term T3 treatment on glioma tumor cell lines. Thyroid hormone action on cell growth, differentiation and survival during development may be of therapeutic relevance Methods and Results 1321N1 cell line, an astrocytoma grade II, and U87MG, a glioblastoma grade IV, were exposed for 2 and 4 days in medium deprived of T3 and in medium containing 1 nM T3. T3 promoted re-differentiation in both cell lines. However, T3 increased cell proliferation in 1321N1 (2 days) which declined thereafter (4 days) while in U87MG resulted in suppression of cell proliferation. At the molecular level, a 2.9 fold increase in the expression of TRα1 receptor was observed in U87MG versus 1321N1, P < 0.05. TRβ1 receptor was undetectable. These changes corresponded to a distinct pattern of T3-induced kinase signaling activation; T3 had no effect on ERK activation in both cell lines but significantly increased phospho-Akt levels in 1321N1. Conclusion. In conclusion, T3 can re-differentiate glioma tumor cells, whereas its effect on cell proliferation appears to be dependent on the type of tumor cell line with aggressive tumors being more sensitive to T3. TRα1 receptor may, at least in part, be implicated in this response

A Novel Mouse Model of Peritoneal Dialysis: Combination of Uraemia and Long-Term Exposure to PD Fluid

Different animal models for peritoneal dialysis (PD) have been used in the past decades to develop PD fluids compatible with patient life and to identify markers of peritoneal fibrosis and inflammation. Only few of those studies have taken into account the importance of uraemia-induced alterations at both systemic and peritoneal levels. Moreover, some animal studies which have reported about PD in a uremic setting did not always entirely succeed in terms of uraemia establishment and animal survival. In the present study we induced uraemia in the recently established mouse PD exposure model in order to obtain a more clinically relevant mouse model for kidney patients. This new designed model reflected both the slight thickening of peritoneal membrane induced by uraemia and the significant extracellular matrix deposition due to daily PD fluid instillation. In addition the model offers the opportunity to perform long-term exposure to PD fluids, as it is observed in the clinical setting, and gives the advantage to knock out candidate markers for driving peritoneal inflammatory mechanisms.Marie Curie actionsPeer Reviewe

Paricalcitol reduces peritoneal fibrosis in mice through the activation of regulatory T cells and reduction in IL-17 production

Fibrosis is a significant health problem associated with a chronic inflammatory reaction. The precise mechanisms involved in the fibrotic process are still poorly understood. However, given that inflammation is a major causative factor, immunomodulation is a possible therapeutic approach to reduce fibrosis. The vitamin D receptor (VDR) that is present in all hematopoietic cells has been associated with immunomodulation. We investigated whether the intraperitoneal administration of paricalcitol, a specific activator of the VDR, modulates peritoneal dialysis fluid (PDF)-induced peritoneal fibrosis. We characterized the inflammatory process in the peritoneal cavity of mice treated or not treated with paricalcitol and analyzed the ensuing fibrosis. The treatment reduced peritoneal IL-17 levels, which strongly correlated with a significantly lower peritoneal fibrotic response. In vitro studies demonstrate that both CD4+ and CD8+ regulatory T cells appear to impact the regulation of IL-17. Paricalcitol treatment resulted in a significantly increased frequency of CD8+ T cells showing a regulatory phenotype. The frequency of CD4+ Tregs tends to be increased, but it did not achieve statistical significance. However, paricalcitol treatment increased the number of CD4+ and CD8+ Treg cells in vivo. In conclusion, the activation of immunological regulatory mechanisms by VDR signaling could prevent or reduce fibrosis, as shown in peritoneal fibrosis induced by PDF exposure in mice.This study was supported by RETICS 06/0016 (VFM, RS) and FIS PI 09/0064 (RS) from the Fondo de Investigaciones Sanitarias (Health Research Fund). MLC was funded by SAF 2013-47611-R, SAF 2010-21249, and SAF 2007-61201 from the Ministerio de Economía y competitividad. MRO was supported by RETICS 12/0021,S2012DMD2321 from the Comunidad Autónoma de Madrid, PI 11/01854 from Fondo Investigaciones Sanitarias. GTGM was supported by Renal Foundation Íñigo Álvarez de Toledo, FIBHULP, and by Severo Ochoa FoundationPeer Reviewe

Design, Development and Initial Validation of a Wearable Particulate Matter Monitoring Solution

Air pollution in one of the main problems that big cities have nowadays. Traffic congestion, heaters, industrial activities, among others produce large quantities of Particulate Matter (PM) that have harmful effects on citizens health. This paper presents the design, development and initial validation of a wearable device for the detection of PM concentration, with communication capacity via WiFi and Bluetooth Low Energy and an end user interface. The results are promising due to the high accuracy of measurements collected by the developed device. This solution is a step forward in empowering citizens to prevent being exposed to high levels of air pollution and is the beginning of what could be a macro-network of air quality sensors within a Smart City. Document type: Part of book or chapter of boo