Implication of the PTN/RPTPß/ζ Signaling Pathway in Acute Ethanol Neuroinflammation in Both Sexes: A Comparative Study with LPS.

Binge drinking during adolescence increases the risk of alcohol use disorder, possibly by involving alterations of neuroimmune responses. Pleiotrophin (PTN) is a cytokine that inhibits Receptor Protein Tyrosine Phosphatase (RPTP) ß/ζ. PTN and MY10, an RPTPß/ζ pharmacological inhibitor, modulate ethanol behavioral and microglial responses in adult mice. Now, to study the contribution of endogenous PTN and the implication of its receptor RPTPß/ζ in the neuroinflammatory response in the prefrontal cortex (PFC) after acute ethanol exposure in adolescence, we used MY10 (60 mg/kg) treatment and mice with transgenic PTN overexpression in the brain. Cytokine levels by X-MAP technology and gene expression of neuroinflammatory markers were determined 18 h after ethanol administration (6 g/kg) and compared with determinations performed 18 h after LPS administration (5 g/kg). Our data indicate that Ccl2, Il6, and Tnfa play important roles as mediators of PTN modulatory actions on the effects of ethanol in the adolescent PFC. The data suggest PTN and RPTPß/ζ as targets to differentially modulate neuroinflammation in different contexts. In this regard, we identified for the first time important sex differences that affect the ability of the PTN/RPTPß/ζ signaling pathway to modulate ethanol and LPS actions in the adolescent mouse brain.

Nobel de Química 2013: combinación de métodos de mecánica molecular y mecánica cuántica para entender y predecir procesos químicos complejos / No disponible

La Real Academia Sueca de Ciencias ha decidido otorgar el Premio Nobel de Química 2013 al investigador austríaco Martin Karplus, Profesor de la Universidad de Strasbourg, Francia y Profesor Emérito de la Universidad de Harvard, USA, al sudafricano Michael Levitt, Profesor de la Universidad de Stanford, USA , y al israelí Arieh Warshel, Profesor de la Universidad del Sur de California, USA, por "el desarrollo de modelos multiescala para sistemas químicos complejos". Los trabajos galardonados con el Premio Nobel de Química de este año se centran en el desarrollo de métodos que utilizan tanto la mecánica molecular como la mecánica cuántica. Sin embargo, a pesar del impresionante avance en software y hardware, el estudio de sistemas complejos, con un elevado número de átomos, como es el caso de las biomoléculas, presenta bastantes dificultades. Para poder llevar a cabo el modelado de las reacciones enzimáticas y otras procesos biomoleculares que implican cambios en la estructura electrónica, tales como formación y ruptura de enlaces covalentes o transferencia de carga, la utilización combinada de mecánica cuántica y mecánica molecular (QM/MM) se ha convertido en el método de elección, siguiendo una idea inicialmente formulada por los investigadores premiados este año (AU)

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Chemistry for 2013 to Austrian researcher Martin Karplus, Professor of the Université de Strasbourg, France and Emeritus Professor at Harvard University, USA, to Southafrican Michael Levitt, Professor at Stanford University, USA, and Israeli Arieh Warshel, Professor at University of Southern California, "USA for the development of multi scale models for complex chemical systems". The work awarded with the Nobel Prize in Chemistry this year focuses on the development of methods that use both molecular mechanics and quantum mechanics. However, despite the impressive advances in software and hardware, the study of complex systems with alarge number of atoms, such as biomolecules, is quite challenging. To carry out modeling of enzymatic reactions and other biomolecular processes involving changes in electronic structure, such as formation and breaking of covalent bonds or charge-transfer processes, the combined use of quantum mechanics and molecular mechanics (QM/MM) has become the method of choice, following an idea originally formulated by this year’s awarded researchers (AU)

Structure of micelle-bound adrenomedullin: a first step toward the analysis of its interactions with receptors and small molecules.

Adrenomedullin (AM) is a regulatory peptide which plays many physiological roles including vasodilatation, bronchodilatation, hormone secretion regulation, growth, apoptosis, angiogenesis, and antimicrobial activities, among others. These regulatory activities make AM a relevant player in the pathophysiology of important diseases such as cardiovascular and renal conditions, cancer, and diabetes. Therefore, molecules that target the AM system have been proposed as having therapeutic potential. To guide the design and characterization of such molecules, we elucidated the three-dimensional structure of AM in a membrane mimicking medium using NMR spectroscopy methods. Under the employed experimental conditions, the structure can be described as composed by a central α-helical region, spanning about one third of its total length, flanked by two disordered segments at both N- and C-termini. The structure of AM in water is completely disordered. The 22-34 region of AM has a general tendency to adopt a helical structure under the employed experimental conditions. Furthermore, the study of the interaction of AM with two of its modulators has also been performed by using chemical shift perturbation analysis NMR methods with two-dimensional (2D)-TOCSY experiments, assisted with molecular modeling protocols. We expect these results will help in better understanding the interactions of AM with its receptor and binding proteins/molecules and in the development of novel modulators of AM activities.

Síntesis de Inhibidores Selectivos de MMP-2 utilizando Química Click / Synthesis of Selective MMP-2 Inhibitors Using Click Chemistry

Siguiendo una estrategia de diseño basado en fragmentos, se describe la síntesis de una nueva serie de inhibidores de MMP-2. Para ello, se parte de un fragmento que contiene simultáneamente un grupo hidroxamato como Zinc Binding Group (ZBG) y un grupo azida. Esta subunidad se conecta mediante química “click" con otros fragmentos lipófilos que contienen un alquino terminal y que han sido seleccionados para interaccionar de manera selectiva con el subsitio S1’ de la MMP-2. Los compuestos sintetizados más activos, 20 y 21, presentan una alta potencia inhibitoria en MMP-2. Además, el compuesto 20 presenta un prometedor perfil de selectividad frente a algunas metaloproteasas consideradas anti-diana en cáncer, como MMP-8 y MMP-9(AU)

A new series of selective MMP-2 inhibitors is described, following a fragment-based drug design approach. A fragment containing an azide group and a well known hydroxamate ZBG, was synthesized. A click chemistry reaction was used to connect the azide to lipophilic alkynes selected to interact selectively with the S1’ subunit of MMP-2. The most active compounds, 20 and 21, displayed high values of IC50 against MMP-2. In addition, compound 20 has shown also a promissing selectivity profile against some antitarget metalloproteinases in cancer, such as MMP-8, and MMP-9(AU)

Are adrenomedullin positive modulators novel matrix metalloproteinase inhibitors?

Las metaloproteasas de la matriz (MMPs) pertenecen a la familia de enzimasque contienen zinc y juegan un papel predominante en la degradación del tejidoconectivo. Por ello se consideran dianas terapéuticas para procesos de inflamacióny enfermedades malignas y degenerativas. Por otro lado, se ha demostrado recientementeque un miembro de esta familia, MMP-2, una colagenasa de tipo IV tambiénconocida como gelatinasa A, es capaz de degradar un péptido angiogénico denominadoadrenomedulina (AM) (1). AM es una hormona peptídica que desarrolla unpapel importante en diversas patologías como diabetes, hipertensión y cáncer. Seha identificado mediante un cribado de alto rendimiento (HTS) de la colección decompuestos del Instituto Nacional del Cáncer (NCI), una serie de moduladores coninteresante actividad hipotensora (2). El mecanismo de acción de estos moduladoreses desconocido y nosotros proponemos que pueden afectar a la biodisponibilidadde la AM en el torrente sanguíneo por medio de la inhibición de la actividad dela MMP-2. En este trabajo presentamos un estudio teórico que hace uso de técnicascomo mecánica molecular, docking y Cribado Virtual con el objetivo de demostraresa hipótesis. A continuación del estudio computacional se llevó a cabo la evaluaciónbiológica de algunos compuestos, permitiéndonos proponer un nuevo tipo deZBG que puede ser interesante para el diseño de nuevos inhibidores de MMPS, coninterés como agentes anticancerosos y antiangiogénicos

Matrix metalloproteinases (MMPs), are a family of structurally related zinccontaining enzymes that play a major role in the breakdown of connective tissueand therefore, are targets for therapeutic inhibitors in many inflammatory,malignant, and degenerative diseases. On the other hand, it has been recentlydemonstrated that one of these enzymes, MMP-2, a type IV collagenase, termedgelatinase A, cleaves the angiogenic peptide adrenomedullin (AM) (1). AM is apeptide hormone that plays a critical role in several diseases such as diabetes,hypertension and cancer. In a High Throughput Screening (HTS) carried out at theNational Cancer Institute (NCI), a series of AM modulators were identified, with aninteresting hypotensive activity (2). In order to shed light into the mechanism ofaction of these interesting compounds, we have hypothesized that they may be affecting the biodisponibility of AM in the blood stream by inhibiting the MMP-2protease activity. In the present work, we present a theoretical study, making useof molecular mechanics, docking and virtual screening techniques, with the aim ofdemonstrating this hypothesis. Biological evaluation of MMP-2 inhibition by someselected compounds, followed the computational work, leading us to propose astructurally new type of MMP-2 inhibitors, with possible interest as anticancer andantiangiogenic agents

Estudio teórico del modo de unión entre CDK2 y butirolactona I / Theoretical study of the binding mode between CDK2 and butirolactone I

Las quinasas dependientes de ciclinas (CDKs) juegan un papel importante en la regulación de la división del ciclo celular, lo que supone una prometedora diana para el desarrollo de nuevos agentes terapéuticos frente al cáncer. Se ha realizado un gran esfuerzo durante los últimos años en la búsqueda de pequeñas moléculas que pueden actuar como inhibidores químicos de las CDKs. Estos inhibidores bloquean la progresión del ciclo celular y presentan una interesante actividad antitumoral. La butirolactona I, un producto natural aislado de Aspergillus terreus, que ha mostrado actividad antiproliferativa frente a carcinoma de colon y de páncreas en líneas celulares. Se comporta como un inhibidor competitivo del ATP, mostrando alta afinidad y selectividad frente a CDK1 (cdc2) y CDK2. Debido a la complejidad de la estructura de dicho compuesto, no se conoce bien su modo de unión a la diana farmacológica. Mediante técnicas de modelización molecular, hemos llevado a cabo un estudio que nos ha permitido proponer un modo de unión de dicho compuesto a su diana farmacológica. El complejo de más baja energía obtenido por este procedimiento fue posteriormente sometido a una simulación de dinámica molecular en presencia explícita del disolvente en torno al sitio de unión del ligando. El análisis de dicha simulación indica la formación de un complejo estable, que proponemos como posible modo de unión, y que ha servido como base para el diseño racional de otros ligandos que han sido sintetizados en nuestro laboratorio (AU)

Cyclin dependent kinases (CDKs) play a central role in the regulation of the cell division cycle, which makes them a promising target for the development of therapeutic agents in cancer. Efforts have been made in the last few years in the search for small molecules that can act as chemical inhibitors of CDKs. These inhibitors block cell cycle progression and display interesting antitumor activities. Butirolactone I, a natural product isolated from Aspergillus terreus, has shown antiproliferative activity against colon and pancreatic carcinoma cell lines; it behaves as an ATP competitive inhibitor, displaying a high affinity and selectivity towards CDK1 (cdc2) and CDK2. Due to the structural complexity of this compound, little is known about its binding mode to the pharmacological target. In this work, computer-based design techniques have been used to study the binding mode of butirolactone I to CDK2. The lowest energy complex predicted by these means was later submitted to molecular dynamics simulations in the presence of solvent around the ligandís binding site. The analysis of this simulation indicates the formation of a stable complex, which we propose as a possible binding mode. This has been used as a starting point for the rational design of other ligands that have been synthesized in our laboratory (AU)