Mitigated seizure susceptibility in mice lacking CD137

Mitigated seizure susceptibility in mice lacking CD137

670 P.P. Kale, V. Addepalli / Int. J. Devl Neuroscience 30 (2012) 640–671 formation and neural differentiation without RA treatment. Moreover, NELL2...

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670

P.P. Kale, V. Addepalli / Int. J. Devl Neuroscience 30 (2012) 640–671

formation and neural differentiation without RA treatment. Moreover, NELL2 increased N-cadherin expression in the P19 cells. These data suggest that NELL2 plays a critical role in regulation of neuronal differentiation via regulating N-cadherin expression and cell aggregation. doi:10.1016/j.ijdevneu.2012.03.333

Three-dimensional (3D) modeling of the embryonic shark brain: A basic anatomical tool for studying the development of neuronal systems in a basal vertebrate I. Carrera a,∗ , J. Moss b , D. Davidson b , I. Rodríguez-Moldes a a

Department of Cell Biology and Ecology, University of Santiago de Compostela, CIBUS Bldg, 15706 Santiago de Compostela, Spain b MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh EH4 2XU, UK E-mail address: [email protected] (I. Carrera). The 3D representation of the developing brain provides a detailed framework to study the organization of neuronal systems from the embryo to the young adult. To gain insight into the origin and developmental distribution of the complex morphological structures in the gnathostome brain, we have performed 3D representations of the developing brain in the dogfish Scyliorhinus canicula and mapped the distribution pattern of several neuronal systems identified by their neurochemical contents. The dogfish S. canicula is emerging as an important model organism for comparative studies of brain organization and development because of its phylogenetic position as a basal vertebrate. Using complementary techniques such as immunohistochemistry and optical projection tomography (OPT) microscopy, we have created a 3D imaging of the most representative embryonic stages and their neuroanatomical early expression pattern based on transverse and sagittal sections guided by schematic drawings. Here we show a key stage in the development of the brain, the embryonic stage 28, timepoint in which the expression of neuroactive substances is beginning or already started to express in the main neuronal systems. The events occurring at this particular stage lead to the initiation of a new interaction pattern between neuroactive systems, related to the establishment of the anteroposterior and dorsoventral subdivisions of the brain, thus allowing data meaning for regionalization mapping in vertebrates’ comparative studies. With the 3D representation of different embryonic stages we intend to create the 4D Developing Elasmobranch Brain Atlas, which will be a key resource for understanding the organization of neuronal systems containing modulatory neuroactive substances in the elasmobranch brain, and a reference in the accurate embryonic staging in future evo-devo studies. Supported by: Spanish Dirección General de InvestigaciónFEDER (BFU2010-15816), Xunta de Galicia (10PXIB200051PR) and European Community-ASSEMBLE (grant agreement no. 227799). doi:10.1016/j.ijdevneu.2012.03.334

Mitigated seizure susceptibility in mice lacking CD137 S.G. Kang a,∗ , H.M. Lee b , C.H. Yun b , B.J. Lee b a

Inje University, South Korea b University of Ulsan, South Korea

E-mail address: [email protected] (S.G. Kang). CD137 is a member of tumor necrosis factor/nerve growth factor receptor superfamily. Interaction of CD137 with its ligand (CD137L) affects apoptosis, proliferation, and differentiation of immune cells. Expression of CD137 is not restricted to immune organs, but

detected in a wide variety of tissues such as brain, kidney, lung and heart. However, its role in brain is largely unknown. Recent study reported that CD137 deficiency in the mast cells results in reduced Ca2+ response on stimulation by antigen. Prolonged increase of intracellular free Ca2+ can cause hyper-excitation of neurons, which may result in seizure and neural cell death. Thus we tried to identify role of CD137 in generation of seizure and hippocampal neuronal cell death which induced by kainic acid (KA). Knock-out mice lacking with CD137 showed a decrease in seizure susceptibility and an increased survival rate in response to KA. KA-induced hippocampal neurodegeneration and astrocyte activation were significantly less severe in the CD137 KO mice than in wild mice. Moreover, CD137 KO mice revealed decrease in cfos and cyclooxygenase-2 expression induced by KA. Treatment of agonistic antibody against CD137 increased Ca2+ influx in the primary cultured hippocampal cells. These data suggest that CD137 plays a role in the KA-induced seizure and neurodegeneration via regulating Ca2+ influx. doi:10.1016/j.ijdevneu.2012.03.335

Behavioural dysfunction and delayed neuronal death associated with cholinergic hypofunction during global cerebral ischemia and the effect of rivastigmine, galantamine and choline A. Katyal ∗ , D. Kumaran, M. Udayabanu Dr. B.R. Ambedkar Center for Biomedical Research, University of Delhi, North Campus, New Delhi, India E-mail address: anju [email protected] (A. Katyal). Global cerebral ischemia associated with cardiac arrest engenders selective neuronal death in subiculum, CA1 and CA4 regions of hippocampus. The clinical and experimental evidences reveal that the cognitive dysfunction and neuronal death are the key features of global cerebral ischemia. Further compelling evidences point at direct correlation between increased hippocampal acetylcholine level and learning performance in spatial memory task. We hypothesized that stimulation of cholinergic system may be a potential therapeutic strategy to mitigate the GCI associated neuronal death and memory impairment. In the present study, an effort was made to evaluate the effect of rivastigmine, galantamine and choline on global cerebral ischemia induced memory impairment, cholinergic hypofunction, neuronal inflammation and delayed neuronal death in a mouse model of global cerebral ischemia. BCCAo followed by reperfusion induced spatial and associative memory impairment which was ameliorated with the cholinergic agonists. Cholinergic agonists mitigated the loss of muscarinic and nicotinic receptor expressions. Further in vehicle treated ischemic group choline acetyltransferase and acetylcholinesterase activities were decreased, PARP-1, NADPH oxidase and myeloperoxidase activities were markedly increased in hippocampal homogentae. The histopathological, TUNEL and immunoflurosence studies revealed that GCI/R induced delayed neuronal death, DNA fragmentation as well as increased the high mobility group box-1 protein expression in hippocampal CA1 region. However, choline, rivastigmine and galantamine treatment markedly attenuated the cholinergic hypofunction and neuronal death/inflammation during ischemia. Molecular mechanism of barrel cortex development controlled by thalamocortical axon innervation Asuka Matsui ∗ , Masaharu Ogawa, Aya C. Yoshida, Tomomi Shimogori Molecular Mechanisms of Thalamus Development, BSI RIKEN, Japan E-mail address: asuka [email protected] (A. Matsui).