Comparación de las acciones osteogénicas de la proteína relacionada con la parathormona (PTHrP) en modelos de ratón diabético y con déficit del factor de crecimiento similar a la insulina tipo I (IGF-I)

Trabajo becado con una Beca de Investigación en Biología Molecular FEIOMM 2011. La diabetes mellitus (DM) es una patología metabólica caracterizada por hiperglucemia crónica debida al déficit de producción y/o acción de la insulina. La DM, sobre todo la tipo 1, se asocia comúnmente a osteopenia/osteoporosis y al aumento de riesgo de fracturas. El factor de crecimiento similar a la insulina tipo I (IGF-I), un factor abundante en la matriz ósea que ejerce un papel importante en el desarrollo y mantenimiento de la masa ósea, disminuye en la DM. La proteína relacionada con la parathormona (PTHrP), un modulador del crecimiento y la función osteoblástica, actúa sobre los osteoprogenitores promoviendo la diferenciación osteoblástica y la regeneración ósea. Su expresión disminuye en situación diabética. En este trabajo, hemos evaluado y comparado las acciones osteogénicas de la PTHrP en modelos murinos de DM tipo 1 y deficiente en IGF-I. Los ratones diabéticos por inyección de estreptozotocina presentan una disminución de la masa ósea en los huesos largos, asociada al incremento de proteínas oxidadas y a la disminución de expresión de genes relacionados con la vía Wnt y de la proteína β-catenina, además de mostrar alteraciones en el hueso trabecular vertebral. En el modelo de ratón con déficit de IGF-I, nuestros resultados indican una situación de osteopenia tanto en el fémur (asociado a una inhibición de la vía Wnt) como en la columna (L1-L5). Nuestros hallazgos demuestran que la administración de PTHrP, predominantemente a través de su dominio N-terminal, modula la vía de Wnt canónica en relación a sus acciones osteogénicas en situación diabética y, también en parte, en ausencia de IGF-I

Histamine signaling and metabolism identify potential biomarkers and therapies for lymphangioleiomyomatosis

Inhibition of mTOR is the standard of care for lymphangioleiomyomatosis (LAM). However, this therapy has variable tolerability and some patients show progressive decline of lung function despite treatment. LAM diagnosis and monitoring can also be challenging due to the heterogeneity of symptoms and insufficiency of non-invasive tests. Here, we propose monoamine-derived biomarkers that provide preclinical evidence for novel therapeutic approaches. The major histamine-derived metabolite methylimidazoleacetic acid (MIAA) is relatively more abundant in LAM plasma, and MIAA values are independent of VEGF-D. Higher levels of histamine are associated with poorer lung function and greater disease burden. Molecular and cellular analyses, and metabolic profiling confirmed active histamine signaling and metabolism. LAM tumorigenesis is reduced using approved drugs targeting monoamine oxidases A/B (clorgyline and rasagiline) or histamine H1 receptor (loratadine), and loratadine synergizes with rapamycin. Depletion of Maoa or Hrh1 expression, and administration of an L-histidine analog, or a low L-histidine diet, also reduce LAM tumorigenesis. These findings extend our knowledge of LAM biology and suggest possible ways of improving disease management

The HerMES SPIRE submillimeter local luminosity function

Local luminosity functions are fundamental benchmarks for high-redshift galaxy formation and evolution studies as well as for models describing these processes. Determining the local luminosity function in the submillimeter range can help to better constrain in particular the bolometric luminosity density in the local Universe, and Herschel offers the first opportunity to do so in an unbiased way by imaging large sky areas at several submillimeter wavelengths. We present the first Herschel measurement of the submillimeter 0 < z < 0.2 local luminosity function and infrared bolometric (8-1000 μm) local luminosity density based on SPIRE data from the HerMES Herschel key program over 14.7 deg2. Flux measurements in the three SPIRE channels at 250, 350 and 500 μm are combined with Spitzer photometry and archival data. We fit the observed optical-to-submillimeter spectral energy distribution of SPIRE sources and use the 1/Vmax estimator to provide the first constraints on the monochromatic 250, 350 and 500 μm as well as on the infrared bolometric (8-1000 μm) local luminosity function based on Herschel data. We compare our results with modeling predictions and find a slightly more abundant local submillimeter population than predicted by a number of models. Our measurement of the infrared bolometric (8-1000 μm) local luminosity function suggests a flat slope at low luminosity, and the inferred local luminosity density, 1.31-0.21+0.24 × 108 L ⊙ Mpc-3, is consistent with the range of values reported in recent literature. © 2010 ESO

First results from HerMES on the evolution of the submillimetre luminosity function

We have carried out two extremely deep surveys with SPIRE, one of the two cameras on Herschel, at 250 μm, close to the peak of the far-infrared background. We have used the results to investigate the evolution of the rest-frame 250-μm luminosity function out to z = 2. We find evidence for strong evolution out to z ≃ 1 but evidence for at most weak evolution beyond this redshift. Our results suggest that a significant part of the stars and metals in the universe today were formed at z ≤ 1.4 in spiral galaxies. © 2010 ESO

Biomarkers of extracellular matrix turnover in patients with idiopathic pulmonary fibrosis given nintedanib (INMARK study): a randomised, placebo-controlled study

Background A hallmark of idiopathic pulmonary fibrosis is the excess accumulation of extracellular matrix in the lungs. Degradation of extracellular matrix generates free-circulating protein fragments called neoepitopes. The aim of the INMARK trial was to investigate changes in neoepitopes as predictors of disease progression in patients with idiopathic pulmonary fibrosis and the effect of nintedanib on these biomarkers. Methods In this randomised, double-blind, placebo-controlled trial, patients with a diagnosis of idiopathic pulmonary fibrosis within the past 3 years and forced vital capacity (FVC) of 80% predicted or higher were eligible to participate. Patients were recruited from hospitals, private practices, clinical research units, and academic medical centres. Patients were randomly assigned (1:2) with the use of a pseudo-random number generator to receive oral nintedanib 150 mg twice a day or placebo for 12 weeks in a double-blind fashion, followed by open-label nintedanib for 40 weeks. The primary endpoint was the rate of change in C-reactive protein (CRP) degraded by matrix metalloproteinases 1 and 8 (CRPM) from baseline to week 12 in the intention-to-treat population. The trial has been completed and is registered with ClinicalTrials.gov, number NCT02788474, and with the European Clinical Trials Database, number 2015–003148–38. Findings Between June 27, 2016, and May 15, 2017, 347 patients were randomly assigned to the nintedanib group (n=116) or to the placebo group (n=231). One patient from the placebo group was not treated owing to a randomisation error. At baseline, mean FVC was 97·5% (SD 13·5) predicted. In the double-blind period, 116 patients received nintedanib and 230 patients received placebo. The rate of change in CRPM from baseline to week 12 was −2·57 × 10−3 ng/mL/month in the nintedanib group and −1·90 × 10−3 ng/mL/month in the placebo group (between-group difference −0·66 × 10−3 ng/mL/month [95% CI −6·21 × 10−3 to 4·88 × 10−3]; p=0·8146). The adjusted rate of change in FVC over 12 weeks was 5·9 mL in the nintedanib group and −70·2 mL in the placebo group (difference 76·1 mL/12 weeks [31·7 to 120·4]). In patients who received placebo for 12 weeks followed by open-label nintedanib, rising concentrations of CRPM over 12 weeks were associated with disease progression (absolute decline in FVC ≥10% predicted or death) over 52 weeks. In the double-blind period, serious adverse events were reported in eight (7%) patients given nintedanib and 18 (8%) patients given placebo. Grade 3 diarrhoea was reported in two (2%) patients in the nintedanib group and two (1%) patients in the placebo group. No patients had grade 4 diarrhoea. Interpretation In patients with idiopathic pulmonary fibrosis and preserved lung function, treatment with nintedanib versus placebo for 12 weeks did not affect the rate of change in CRPM but was associated with a reduced rate of decline in FVC. These results suggest that change in CRPM is not a marker of response to nintedanib in patients with idiopathic pulmonary fibrosis