22.12.13

JO JO JO!

Volvemos en gloria y majestad (mas bien vuelvo). Ahora subiré todas los diseños para todos!
Disfruten!


Now I come back with christmas ideas, but with a scientific view point. Now I with upload the last designs for everyone! 
Enjoy !!!

JO JO JO JO!!




16.9.13

New Article with drawings: Wnt Signaling in Skeletal Muscle Dynamics: Myogenesis, Neuromuscular Synapse and Fibrosis

Wnt Signaling in Skeletal Muscle Dynamics: Myogenesis, Neuromuscular Synapse and Fibrosis


Abstract

The signaling pathways activated by Wnt ligands are related to a wide range of critical cell functions, such as cell division, migration, and synaptogenesis. Here, we summarize compelling evidence on the role of Wnt signaling on several features of skeletal muscle physiology. We briefly review the role of Wnt pathways on the formation of muscle fibers during prenatal and postnatal myogenesis, highlighting its role on the activation of stem cells of the adult muscles. We also discuss how Wnt signaling regulates the precise formation of neuromuscular synapses, by modulating the differentiation of presynaptic and postsynaptic components, particularly regarding the clustering of acetylcholine receptors on the muscle membrane. In addition, based on previous evidence showing that Wnt pathways are linked to several diseases, such as Alzheimer's and cancer, we address recent studies indicating that Wnt signaling plays a key role in skeletal muscle fibrosis, a disease characterized by an increase in the extracellular matrix components leading to failure in muscle regeneration, tissue disorganization and loss of muscle activity. In this context, we also discuss the possible cross-talk between the Wnt/β-catenin pathway with two other critical profibrotic pathways, transforming growth factor β and connective tissue growth factor, which are potent stimulators of the accumulation of connective tissue, an effect characteristic of the fibrotic condition. As it has emerged in other pathological conditions, we suggests that muscle fibrosis may be a consequence of alterations of Wnt signaling activity.

22.6.13

New Review!!: Wnt signaling in the regulation of adult hippocampal neurogenesis

Wnt signaling in the regulation of adult hippocampal neurogenesis

Lorena Varela-Nallar and Nibaldo C. Inestrosa

In the adult brain new neurons are continuously generated mainly in two regions, the subventricular zone of the lateral ventricles and the subgranular zone (SGZ) in the hippocampal dentate gyrus. In the SGZ, radial neural stem cells give rise to granule cells that integrate into the hippocampal circuitry and are relevant for the plasticity of the hippocampus. Loss of neurogenesis impairs learning and memory, suggesting that this process is important for adult hippocampal function. Adult neurogenesis is tightly regulated by multiple signaling pathways, including the canonical Wnt/beta-catenin pathway. This pathway plays important roles during the development of neuronal circuits and in the adult brain it modulates synaptic transmission and plasticity. Here, we review current knowledge on the regulation of adult hippocampal neurogenesis by the Wnt/beta-catenin signaling cascade and the potential mechanisms involved in this regulation. Also we discuss the evidence supporting that the canonical Wnt pathway is part of the signaling mechanisms involved in the regulation of neurogenesis in different physiological conditions. Finally, some unsolved questions regarding the Wnt-mediated regulation of neurogenesis are discussed.

New Review!! WNT signalling in neuronal maturation and synaptogenesis

WNT signalling in neuronal maturation and synaptogenesis

Silvana B. Rosso1 and Nibald C. Inestros

The Wnt signaling pathway plays a role in the development of the central nervous system (CNS) and growing evidence indicates that Wnts also regulates the structure and function of the adult nervous system. Wnt components are key regulators of a variety of developmental processes, including embryonic patterning, cell specification, and cell polarity. In the nervous system, Wnt signaling also regulates the formation and function of neuronal circuits by controlling neuronal differentiation, axon outgrowth and guidance, dendrite development, synaptic function and neuronal plasticity. Wnt factors can signal through three very well characterized cascades: canonical or β-catenin pathway, planar cell polarity pathway and calcium pathway that control different processes. However, divergent downstream cascades have been identified to control neuronal morphogenesis. In the nervous system, the expression of Wnt proteins is a highly controlled process. In addition, deregulation of Wnt signaling has been associated with neurodegenerative diseases. Here, we will review different aspects of neuronal and dendrite maturation, including spinogenesis and synaptogenesis. Finally, the role of Wnt pathway components on Alzheimer’s disease will be revised.

13.6.13

New paper with drawings: Canonical Wnt Signaling New Paper with drawings!: Protects Hippocampal Neurons from Aβ Oligomers: Role of Non-Canonical Wnt-5a/Ca2+ in Mitochondrial Dynamics

Canonical Wnt Signaling Protects Hippocampal Neurons from Aβ Oligomers: Role of Non-Canonical Wnt-5a/Ca2+ in Mitochondrial Dynamics

Carmen Silva-Alvarez1, Macarena Arrazola2, Juan A. Godoy1, Daniela Ordenes1 and Nibaldo C. Inestrosa1, 2*
1Cell and Molecular Biology, Pontifical Catholic University of Chile, Chile
2Cell and Molecular Biology, Pontifical Catholic University of Chile, Chile

Alzheimer´s disease (AD) is the most common type of age-related dementia. The disease is characterized by a progressive loss of cognitive abilities, severe neurodegeneration, synaptic loss and mitochondrial dysfunction. The Wnt signaling pathway participates in the development of the central nervous system and growing evidence indicates that Wnts also regulate the function of the adult nervous system. We report here, that indirect activation of canonical Wnt/β-catenin signaling using Bromoindirubin-30-Oxime (6-BIO), an inhibitor of glycogen synthase kinase-3β, protects hippocampal neurons from amyloid-β (Aβ) oligomers with the concomitant blockade of neuronal apoptosis. More importantly, activation with Wnt-5a, a non-canonical Wnt ligand, results in the modulation of mitochondrial dynamics, prevents changes induced by Aβ oligomers in mitochondrial fission-fusion dynamics and modulates Bcl-2 increases induced by oligomers. The canonical Wnt-3a ligand neither the secreted Frizzled-Related Protein (sFRP), a Wnt scavenger, did not prevent these effects. In contrast, some of the Aβ oligomer effects were blocked by Ryanodine. We conclude that canonical Wnt/β-catenin signaling controls neuronal survival, and that non-canonical Wnt/Ca2+ signaling controls mitochondrial dysfunction. To our knowledge, this is the first report showing that activation of non-canonical Wnt-5a/Ca2+signaling prevents Aβ oligomer neurotoxicity. Since mitochondrial dysfunction is present in neurodegenerative diseases, the therapeutic possibilities of the activation of Wnt signaling are evident.




23.5.13

Paper with drawings!: "Wnt signaling: Role in LTP, neural networks and memory."

Wnt signaling: Role in LTP, neural networks and memory.

Oliva CA, Vargas JY, Inestrosa NC.

Wnt components are key regulators of a variety of developmental processes, including embryonic patterning, cell specification, and cell polarity. The Wnt signaling pathway participates in the development of the central nervous system and growing evidence indicates that Wnts also regulates the function of the adult nervous system. In fact, most of the key components including Wnts and Frizzled receptors are expressed in the adult brain. Wnt ligands have been implicated in the regulation of synaptic assembly as well as in neurotransmission and synaptic plasticity. Deregulation of Wnt signaling has been associated with several pathologies, and more recently has been related to neurodegenerative diseases and to mental and mood disorders. In this review, we focus our attention on the Wnt signaling cascade in postnatal life and we review in detail the presence of Wnt signaling components in pre- and postsynaptic regions. Due to the important role of Wnt proteins in wiring neural circuits, we discuss recent findings about the role of Wnt pathways both in basal spontaneous activities as well as in activity-dependent processes that underlie synaptic plasticity. Finally, we review the role of Wnt in vivo and we finish with the most recent data in literature that involves the effect of components of the Wnt signaling pathway in neurological and mental disorders, including a special emphasis on in vivo studies that relate behavioral abnormalities to deficiencies in Wnt signaling, as well as the data that support a neuroprotective role of Wnt proteins in relation to the pathogenesis of Alzheimer's disease.

Paper with drawings! "Peroxisome Proliferator-Activated Receptor (PPAR) γ and PPARα Agonists Modulate Mitochondrial Fusion-Fission Dynamics: Relevance to Reactive Oxygen Species (ROS)-Related Neurodegenerative Disorders?"


Peroxisome Proliferator-Activated Receptor (PPAR) γ and PPARα Agonists Modulate Mitochondrial Fusion-Fission Dynamics: Relevance to Reactive Oxygen Species (ROS)-Related Neurodegenerative Disorders?

Zolezzi JM, Silva-Alvarez C, Ordenes D, Godoy JA, Carvajal FJ, Santos MJ, Inestrosa NC.

Recent studies showed that the activation of the retinoid X receptor, which dimerizes with peroxisome proliferator-activated receptors (PPARs), leads to an enhanced clearance of Aβ from the brain of transgenic mice model of Alzheimer's disease (AD), because an increased expression of apolipoprotein E and it main transporters. However, the effects observed must involve additional underlying mechanisms that have not been yet explored. Several studies conducted in our laboratory suggest that part of the effects observed for the PPARs agonist might involves mitochondrial function and, particularly, mitochondrial dynamics. In the present study we assessed the effects of oxidative stress challenge on mitochondrial morphology and mitochondrial dynamics-related proteins in hippocampal neurons. Using immunofluorescence, we evaluated the PPARγ co-activator 1α (PGC-1α), dynamin related protein 1 (DRP1), mitochondrial fission protein 1 (FIS1), and mitochondrial length, in order to determine if PPARs agonist pre-treatment is able to protect mitochondrial population from hippocampal neurons through modulation of the mitochondrial fusion-fission events. Our results suggest that both a PPARγ agonist (ciglitazone) and a PPARα agonist (WY 14.643) are able to protect neurons by modulating mitochondrial fusion and fission, leading to a better response of neurons to oxidative stress, suggesting that a PPAR based therapy could acts simultaneously in different cellular components. Additionally, our results suggest that PGC-1α and mitochondrial dynamics should be further studied in future therapy research oriented to ameliorate neurodegenerative disorders, such as AD.

Paper published

4.5.13

Review: Wnt Signaling Roles on the Structure and Function of the Central Synapses: Involvement in Alzheimer’s Disease

Review with drawings accepted !  Click Review Here !!

This is a old version of drawings of Graphique-science, but now are coming new versions!

 Wnts compromise a large family of secreted glycoproteins that have shown to be part of the signaling molecules that regulate several aspects of development such as axis formation and midbrain development [1, 2]. In mammals at least 19 Wnt members have been found. The interaction of a Wnt protein with members of the Frizzled (Fz) family of seven-pass transmembrane cell-surface receptors triggers the activation of the Wnt signaling pathway . In human and mice, 10 members of the Fz family have been identified. In addition, receptor-like tyrosine kinase (Ryk) and receptor tyrosine kinase-like orphan receptor (Ror2) have been identified as alternative Wnt receptors [6-8]. Different Wnt signaling cascades are activated downstream the Wnt receptors, identified as Wnt/β-catenin or canonical pathway, and β-catenin-independent or non-canonical pathways. The canonical pathway involves the transcription of Wnt target genes, while activation of non-canonical Wnt pathways may induce either an increase in intracellular calcium concentration or activation of the c-Jun-N-terminal kinase (JNK) cascade.

24.4.13

New drawing model of a Signaling by Graphique-science


A couple of weeks ago, I was looking for a new design of drawings. So now, here is my new style of creations !!. More definition and more design with a new concept. Enjoy !  I will accept observations !.

24.3.13

Neurogenesis Re-Loaded !!


Neurogenesis in the Sub-Granular Zone (SGZ) of the hippocampus Reloaded!!. This drawing was created in comparison with one of my firsts design in the neurogenesis. Thanks to the creativity and patience to make everyday a nice work !

(Hace un tiempo había realizado este dibujo pero sin los conocimientos que he ido adquiriendo en el tiempo. Hoy año 2013 Graphique-science esta a la vanguardia!!!)

20.3.13

First drawing in a review !!

http://link.springer.com/article/10.1007%2Fs12035-013-8435-5

Peroxisome Proliferator-activated Receptors and Alzheimer's Disease: Hitting the Blood–Brain Barrier  

Juan M. Zolezzi and Nibaldo C. Inestrosa

The blood–brain barrier (BBB) is often affected in several neurodegenerative disorders, such as Alzheimer's disease (AD). Integrity and proper functionality of the neurovascular unit are recognized to be critical for maintenance of the BBB. Research has traditionally focused on structural integrity more than functionality, and BBB alteration has usually been explained more as a consequence than a cause. However, ongoing evidence suggests that at the early stages, the BBB of a diseased brain often shows distinct expression patterns of specific carriers such as members of the ATP-binding cassette (ABC) transport protein family, which alter BBB traffic. In AD, amyloid-β (Aβ) deposits are a pathological hallmark and, as recently highlighted by Cramer et al. (2012), Aβ clearance is quite fundamental and is a less studied approach. Current knowledge suggests that BBB traffic plays a more important role than previously believed and that pharmacological modulation of the BBB may offer new therapeutic alternatives for AD. Recent investigations carried out in our laboratory indicate that peroxisome proliferator-activated receptor (PPAR) agonists are able to prevent Aβ-induced neurotoxicity in hippocampal neurons and cognitive impairment in a double transgenic mouse model of AD. However, even when enough literature about PPAR agonists and neurodegenerative disorders is available, the problem of how they exert their functions and help to prevent and rescue Aβ-induced neurotoxicity is poorly understood. In this review, along with highlighting the main features of the BBB and its role in AD, we will discuss information regarding the modulation of BBB components, including the possible role of PPAR agonists as BBB traffic modulators.

First paper with drawings !

http://iospress.metapress.com/content/y05258137g173l5v/

Transforming Growth Factor β1 Modulates Amyloid β-Induced Glial Activation through the Smad3-Dependent Induction of MAPK Phosphatase-1

 B Flores and R von Bernhardi

 Chronic neuroinflammation has been proposed as a driving force for Alzheimer's disease (AD), which is characterized by amyloid-β (Aβ) deposition, neurofibrillary tangles, neuronal loss, and activation of glial cells. Persistent activation of mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-κB) pathway has been reported, which induces an increased expression of inflammatory mediators. Transforming growth factor β1 (TGFβ1) is an inflammation modulator whose levels are increased in AD. However, its canonical signaling pathway, Smad, appears to be impaired. Our previous findings indicate that TGFβ1 plays a key role in the pathogenesis of neuroinflammation, but the molecular mechanisms underlying its effects are not completely elucidated. Here, we studied the potential role of MKP-1, a phosphatase that exerts negative regulation on MAPK signaling, in the modulatory actions of TGFβ1. Using rat primary glial cultures, we found that pretreatment with TGFβ1 for 48 h reduced the production of inflammatory mediators induced by Aβ42, a result that was associated with prevention of MAPK p38 activation, attenuation of NF-κB p65 nuclear translocation, and an increase in MKP-1 levels. Moreover, suppression of MKP-1 expression by siRNA and inhibition of Smad3 reversed the modulation of inflammatory response exerted by TGFβ1. These results indicate that TGFβ1 induces the expression of MKP-1 in glial cells through the Smad pathway and inhibits MAPK and NF-κB signaling, thus revealing a novel mechanism for the neuroprotective actions of TGFβ1. Further research would be important in order to characterize the role of this mechanism in the pathogenesis of AD.

1.1.13

The dark side of the brain !!

Is the first publication of the year. So, we can start with a classic image and with a phrase of Elbert Hubband:
"The brain is a commodity used to fertilize ideas.”