Search

It is already widely known that the different brain areas involved in blood pressure control, are highly vulnerable to the deleterious effects of this condition. Of particular concern are hypertensive and neuroinflammatory-dependent injuries that by modifying blood flow account for artery structural and functional alterations. It was thus our intention to establish if expression changes of some key brain neuroinflammatory factors like caspase-1,3, NF-kB, IL-1β and NLRP3, which are known to control blood pressure, are actively involved with inflammation regulatory events in a highly valuable spontaneously hypertensive rat (SHR) model. Indeed, notably increased (p 0.001) caspase-1, NLRP3 and IL-1β mRNA levels were detected in amygdalar plus hypothalamic areas of SHR. Contextually, similar up-regulated levels of these factors were also reported in brainstem nuclei with respect to the few hippocampal areas. This trend was supported by moderate increases (p 0.05) of NLRP3 in amygdalar and brainstem sites, while notably greater expression differences of NF-kB protein were observed in hippocampal and hypothalamic areas of SHR. At the same time, moderately increased levels of iNOS were typical of all of the above brain areas with the exception of the consistently (p 0.01) increased levels featured in the brainstem. Moreover, even immunohistochemical evaluations supplied notably and moderately increased cleaved caspase-3 cell levels in hippocampus and hypothalamus areas, respectively. Overall, evident hypertensive bouts correlated to neuroinflammatory events, especially in brain areas controlling blood pressure, tend to underlie the value of novel therapeutic approaches designed to improve brain blood flow and subsequently reduce hypertensive-dependent cerebral complications.

The redox state of the cell is involved in the regulation of many physiological functions as well as in the pathogenesis of several diseases, and is strictly dependent on the amount of iron in its catalytically active state. Alterations of iron homeostasis determine increased steady-state concentrations of Reactive Oxygen Species (ROS) that cause lipid peroxidation, DNA damage and altered protein folding. Ferritin keeps the intracellular iron in a non-toxic and readily available form and consequently plays a central role in iron and redox homeostasis. The protein is composed by 24 subunits of the H- and L-type, coded by two different genes, with structural and functional differences. The aim of this study was to shed light on the role of the single H ferritin subunit (FHC) in keeping the native correct protein three-dimensional structure. To this, we performed Raman spectroscopy on protein extracts from K562 cells subjected to FHC silencing. The results show a significant increase in the percentage of disordered structures content at a level comparable to that induced by H2O2 treatment in control cells. ROS inhibitor and iron chelator were able to revert protein misfolding. This integrated approach, involving Raman spectroscopy and targeted-gene silencing, indicates that an imbalance of the heavy-to-light chain ratio in the ferritin composition is able to induce severe but still reversible modifications in protein folding and uncovers new potential pathogenetic mechanisms associated to intracellular iron perturbation.

Display Omitted Photolithography and micromolding techniques for fabrication of 3D polymeric pillared scaffolds.Micro scale features characterized by the same length scale of fibrous proteins constituents of the extracellular matrix.Employment of biocompatible, bioresorbable long term degradation polymer for biomedical application. Material science, cell biology, and engineering are all part of the research field of tissue engineering. It is the application of knowledge, methods and instrumentations of engineering and life science to the development of biocompatible solutions for repair and/or replace tissues and damaged organs.Last generation microfabrication technologies utilizing natural and synthetic biomaterials allow the realization of scaffolds resembling tissue-like structures as skin, brain, bones, muscles, cartilage and blood vessels.In this work we describe an effective and simple micromolding fabrication process allowing the realization of 3D polycaprolactone (PCL) scaffold for human neural stem cells (hNSC) culture. Scanning Electron Microscopy has been used to investigate the micro and nano features characterizing the surface of the device. Immunofluorescence analysis showed how, after seeding cells onto the substrate, healthy astrocytes grew up in a well-organized 3D network. Thus, we proposed this effective fabrication method for the production of nanopatterned PCL pillared scaffold providing a biomimetic environment for the growth of hNSC, a promising and efficient means for future applications in tissue engineering and regenerative medicine.

Interaction of the orexinergic (ORXergic) neuronal system with the excitatory (glutamate, l -Glu) or the inhibitory (GABA) neurosignaling complexes evokes major homeostatic physiological events. In this study, effects of the two ORXergic neuropeptides (ORX-A/B) on their receptor (ORX-2R) expression changes were correlated to feeding and grooming actions of the hibernating hamster ( Mesocricetus auratus ). Infusion of the central amygdala nucleus (CeA) with ORX-A caused hamsters to consume notable quantities of food, while ORX-B accounted for a moderate increase. Interestingly the latter neuropeptide was responsible for greater frequencies of grooming with respect to both controls and the hamsters treated with ORX-A. These distinct behavioral changes turned out to be even greater in the presence of l -Glu agonist (NMDA) while the α 1 GABA A receptor agonist (zolpidem, Zol) greatly reduced ORX-A-dependent feeding bouts. Moreover, ORX-A + NMDA mainly promoted greater ORX-2R expression levels with respect to ORX-A-treated hamsters while ORX-B + Zol was instead largely responsible for a down-regulatory trend. Overall, these features point to CeA ORX-2R sites as key sensory limbic elements capable of regulating eating and grooming responses, which may provide useful insights regarding the type of molecular mechanism(s) operating during feeding bouts.

Membranes have become of great interest for tissue engineering application, since they offer the advantage of developing neuronal tissue that may be used in implantable or in vitro hybrid systems for the simulation of brain function. The behaviour of neurons isolated from the hippocampus on membranes with different surface properties was investigated. The different membranes used as substrates for cell adhesion consisted of polyester (PE), modified polyetheretherketone (PEEK-WC), fluorocarbon (FC) and polyethersulfone (PES), all of which coated with poly-l-lysine (PLL) in order to have the same functional groups interacting with cells. The membranes exhibited different morphological surface properties in terms of pore size, porosity and roughness. Hippocampal neurons exhibited a different morphology in response to varying the properties of the membrane surface. Indeed, cells grown on the smoother membranes and namely FC and PES membranes displayed a large number of neurites with consequent formation of bundles. As a consequence while a very complex network was formed on these membranes, cells tend to, instead, form aggregates and most of the processes are developed inside the pores of the membranes when rougher PEEK-WC surfaces were used. In addition, the secretion of brain-derived neurotrophic factor (BDNF) was expressed at high levels in neurons grown on FC membranes with respect to the other membranes. Taken together these results suggest the pivotal role played by membrane surface properties in the adhesion and growth of the hippocampal neurons, which must be considered in the development of tailored membranes for neural tissue engineering. © 2008 Elsevier B.V. All rights reserved.