“Generation of a new model of patellar tendinopathy in rats which mimics the human sports pathology: A pilot study” by David Domínguez, Paola Contreras-Muñoz, Silvia Lope, Gil Rodas, G. and Mario Marotta. Apunts. Medicina de l’Esport, 2017, 52:194, 53-59. DOI: 10.1016/j.apunts.2017.01.002
Introduction: Patellar tendon pathophysiology is not still fully understood. The collection of clinical samples from athletes that could permit the analysis of the tendinopathy progression, especially in the early stages, is difficult. For that reason, the purpose of this study is to develop a new experimental animal model of patellar tendinopathy in rats which mimics the human tendinopathy by in vivo intratendinous collagenase injection in the proximal portion of the patellar tendon. Material and methods: The experimental model used was 8-week-old male Wistar rats (N = 4). The administration of collagenase was performed by ultrasound-guided puncture at the level of the proximal and deep portion of the patellar tendon in anesthetized animals. The tendon lesion was evaluated 48 h after injury by magnetic resonance and then, the animals were euthanized and the patellar tendons were collected for histological evaluation. Results: The collagenase-induced lesion model demonstrated important similarities with the human patellar tendinopathy in the region of the proximal insertion. Conclusions: The experimental model of patellar tendinopathy in rat model induces a degeneration and distortion of the patellar tendon architecture in its proximal portion, which closely mimics to that seen in human patellar tendinopathy, and could represent an excellent preclinical model for the study of new therapies focused on treatment of tendinopathy.
“Metabolomics of Therapy Response in Preclinical Glioblastoma: A Multi-Slice MRSI-Based Volumetric Analysis for Noninvasive Assessment of Temozolomide Treatment” by N. Arias-Ramos, L. Ferrer-Font, S. Lope-Piedrafita, V. Mocioiu, M. Julià-Sapé , M. Pumarola, C. Arús and A. P. Candiota. Metabolites, 2017, 18;7(2). pii: E20. DOI: 10.3390/metabo7020020.
Glioblastoma (GBM) is the most common and aggressive glial primary tumor with a survival average of 14-15 months, even after application of standard treatment. Non-invasive surrogate biomarkers of therapy response may be relevant for improving patient survival. Nosological images of therapy response using a semi-supervised source extraction approach in preclinical GBM based on single slice Magnetic Resonance Spectroscopic Imaging (MRSI) was previously describe by our group. However, because of GBM heterogeneity, relevant response information could be missed just by studying one slice. Therefore, the goal of this work was to acquire 3D-like information from preclinical GBM under a longitudinal treatment protocol, using a multi-slice MRSI approach.
Nosological maps were obtained based on semi-supervised convex Non-negative Matrix Factorization and each voxel was colored according to the contribution to the spectral pattern of each one of the three sources or characteristic spectral patterns: Normal brain, actively proliferating tumour or responding tumour.
Heterogeneous response levels were observed and three arbitrary groups of treated animals were defined as: high response, intermediate response, and low response. Histopathological studies showed an inverse correlation between the responding pattern level and Ki67 proliferation rate.
“Neonatal handling enduringly decreases anxiety and stress responses and reduces hippocampus and amygdala volume in agenetic model of differential anxiety: Behavioral-volumetric associations in the Roman rats trains” by C. Río-Álamos, I. Oliveras, M. A. Piludu, C. Gerbolés, T. Cañete, G. Blázquez, S. Lope-Piedrafita, E. Martínez-Membrives, R. Torrubia, A. Tobeña, and A. Fernández-Teruel. European Neuropsychopharmacology, 2017, 27: 146–158. DOI: 10.1016/j.euroneuro.2016.12.003
The hippocampus and amygdala have been proposed as key neural structures related to anxiety. A more active hippocampus/amygdala system has been related to greater anxious responses in situations involving conflict/novelty. The Roman Low- (RLA) and High-avoidance (RHA) rat strains constitute a genetic model of differential anxiety. Relative to RHA rats, RLA rats exhibit enhanced anxiety/fearfulness, augmented hippocampal/amygdala c-Fos expression following exposure to novelty/conflict, increased hippocampal neuronal density and higher endocrine responses to stress. Neonatal handling (NH) is an environmental treatment with long-lasting anxiety/stress-reducing effects in rodents. Since hippocampus and amygdala volume are supposed to be related to anxiety/fear, it was hypothesized a greater volume of both areas in RLA than in RHA rats, as well as that NH treatment would reduce anxiety and the volume of both structures. Adult untreated and NH-treated RHA and RLA rats were tested for anxiety, sensorimotor gating (PPI), stress-induced corticosterone and prolactin responses, two-way active avoidance acquisition and in vivo 7 T 1H-Magnetic resonance image.
As expected, untreated RLA rats showed higher anxiety and post-stress hormone responses, as well as greater hippocampus and amygdala volumes than untreated RHA rats. NH decreased anxiety/stress responses, especially in RLA rats, and significantly reduced hippocampus and amygdala volumes in this strain. Dorsal striatum volume was not different between the strains nor it was affected by NH. Finally, there were positive associations (as shown by correlations, factor analysis and multiple regression) between anxiety and PPI and hippocampus/amygdala volumes.
“Mutation of the 3-Phosphoinositide-Dependent Protein Kinase 1
(PDK1) Substrate-Docking Site in the Developing Brain Causes
Microcephaly with Abnormal Brain Morphogenesis Independently of
Akt, Leading to Impaired Cognition and Disruptive Behaviors” by Lluís Cordón-Barris, Sònia Pascual-Guiral, Shaobin Yang, Lydia Giménez-Llort, Silvia Lope-Piedrafita, Carlota Niemeyer, Enrique Claro, Jose M. Lizcano, and Jose R. Bayascas. Mol Cell Biol (2016), 36:2967–2982. DOI:10.1128/MCB.00230-16.
This report shows the involvement of PDK1 downstream effectors other than Akt in mouse neuropsychiatric-like disorders, with potential face and construct validity for negative and cognitive symptoms of schizophrenia. Results point to a prominent function for PIF pocket-dependent kinases as major effectors of this signaling hub downstream of Akt in the etiopathogenesis of schizophrenia that might provide construct validity to the PDK1 L155E mutants.
The phosphoinositide (PI) 3-kinase/Akt signaling pathway plays essential roles during neuronal development. 3-Phosphoinositide-dependent protein kinase 1 (PDK1) coordinates the PI 3-kinase signals by activating 23 kinases of the AGC family, includingAkt. Phosphorylation of a conserved docking site in the substrate is a requisite for PDK1 to recognize, phosphorylate, and activate most of these kinases, with the exception of Akt. This differential mechanism of regulation it has been exploited by generating neuron-specific conditional knock-in mice expressing a mutant form of PDK1, L155E, in which the substrate-docking site binding motif, termed the PIF pocket, was disrupted. As a consequence, activation of all the PDK1 substrates tested except Akt was abolished. The mice exhibited microcephaly, altered cortical layering, and reduced circuitry, leading to cognitive deficits and exacerbated disruptive behavior combined with diminished motivation. The abnormal patterning of the adult brain arises from the reduced ability of the embryonic neurons to polarize and extend their axons, highlighting the essential roles that the PDK1 signaling beyond Akt plays in mediating the neuronal responses that regulate brain development.
||November 29th – December 2nd, 2016
||November 14th, 2016
||Workshop limited to 4 participants (first come, first served)
||Silvia Lope-Piedrafita, PhD (firstname.lastname@example.org)
This course combines a comprehensive series of lectures on the technology of Magnetic resonance spectroscopy and imaging (MRS/MRI) with hands-on laboratory sessions to provide practical demonstrations of key concepts and procedures for preclinical studies.
Whether you are considering MRI as a research tool in your lab or just would like to learn more about MRI, this workshop addresses practical aspects of experimental MRI with laboratory animals and provide valuable hands-on experience on a 7 Tesla Bruker BioSpec spectrometer.
See the workshop brochure for more information or contact Dra. Silvia Lope via email.
“MORPHOLOGICAL MOUSE PHENOTYPING: Anatomy, Histology and Imaging” by Jesús Ruberte París, Ana Carretero Romay, and Marc Navarro Beltrán (2016). Editorial Médica Panamericana.
An extraordinary atlas of mouse anatomy which includes more than 2,200 original images over 600 pages to show the anatomy, histology and cellular structure of mouse organs. This book attempts to provide an overview of the different levels of morphology of the mouse, ranging from gross anatomy and topographical anatomy (to explain the relative position of the organs and structures of a particular body region) down to the microscopic anatomy. Imaging technologies used for that include magnetic resonance imaging (MRI), computed tomography (CT), ultrasonography, angiography, X-ray, and electron microscopy. Also, classical anatomical techniques such as conventional dissection, skeletal preparations, vascular injections, histology and immunohistochemistry have been employed to characterize the mouse morphology.
All MRI images included in this book were acquired at our NMR facility (SeRMN, Universitat Autònoma de Barcelona) in a 7 Tesla Bruker BioSpec spectrometer.
“In vivo and ex vivo Magnetic Resonance Spectroscopy of the Infarct and the Subventricular Zone in Experimental Stroke” by E. Jiménez-Xarrié, M. Davila, S. Gil-Perotín, A. Jurado-Rodríguez, A.P. Candiota, R. Delgado-Mederos, S. Lope-Piedrafita, J.M. García-Verdugo, C. Arús, J. Martí-Fàbregas. Journal of Cerebral Blood Flow & Metabolism, 2015, 35:828–834. DOI: 10.1038/jcbfm.2014.257
Ischemic stroke changes the metabolic pattern in the infarct area and also in other regions such as the ipsilateral subventricular zone (SVZi) where neural progenitor cells (NPCs) proliferation is enhanced in the mammalian and human brains. Magnetic resonance spectroscopy (MRS) provides metabolic information in vivo. With regard to NPCs proliferation, a resonance at 1.28 ppm has been described as an in vivo MRS biomarker of NPCs in the hippocampus of rats and humans. Continue reading In vivo MRS and ex vivo HRMAS in an Ischemic Rat Stroke Model
Dates: February 3rd to 6th, 2015
Organized by the SeRMN of the Autonomous University of Barcelona (UAB).
This course combines a comprehensive series of lectures on the technology of Magnetic resonance spectroscopy and imaging (MRS/MRI) with hands-on laboratory sessions to provide practical demonstrations of key concepts and procedures for preclinical studies. Continue reading 9th Workshop on Magnetic Resonance Spectroscopy and Imaging (MRI/MRS) Applied to Laboratory Animals
Workshop on “Spectra Classification and Decision-Support tools in the clinic”
December 3-4, 2014
Universitat Autònoma Barcelona, Spain
The TRANSACT European Project organizes a two-days scientific workshop on “Spectra Classification and Decision-Support tools in the clinic”. The workshop will be held on December 3-4, 2014 at Hotel Campus UAB which is located in the campus of Universitat Autònoma de Barcelona. Continue reading TRANSACT-ITN Scientific Workshop on “Spectra Classification and Decision-Support tools in the clinic”
“Real-time assessment of 13C metabolism reveals an early lactate increase in the brain of rats with acute liver failure” by Laia Chavarria, Jordi Romero-Giménez, Eva Monteagudo, Silvia Lope-Piedrafita, Juan Cordoba. NMR in Biomedicine (2014) 28:17-23. DOI: 10.1002/nbm.3226
Intracranial hypertension is a severe complication of acute liver failure (ALF) secondary to brain edema. The pathogenesis of cerebral edema in ALF is not clear, but seems to be related to energy metabolism in which lactate may have an important role. The aim of this study was to follow the synthesis of brain lactate using a novel in vivo metabolic technology in a rat model of ALF. Continue reading Hyperpolarized 13C Magnetic Resonance in Acute Liver Failure Rats