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Structural and Ultrastructural Analysis of Cerebral Cortex, Cerebellum, and Hypothalamus from Diabetic Rats  [PDF]
Juan P. Hernández-Fonseca,Jaimar Rincón,Adriana Pedrea ez,Ninoska Viera,José L. Arcaya,Edgardo Carrizo,Jesús Mosquera
Experimental Diabetes Research , 2009, DOI: 10.1155/2009/329632
Abstract: Autonomic and peripheral neuropathies are well-described complications in diabetes. Diabetes mellitus is also associated to central nervous system damage. This little-known complication is characterized by impairment of brain functions and electrophysiological changes associated with neurochemical and structural abnormalities. The purpose of this study was to investigate brain structural and ultrastructural changes in rats with streptozotocin-induced diabetes. Cerebral cortex, hypothalamus, and cerebellum were obtained from controls and 8 weeks diabetic rats. Light and electron microscope studies showed degenerative changes of neurons and glia, perivascular and mitochondrial swelling, disarrangement of myelin sheath, increased area of myelinated axons, presynaptic vesicle dispersion in swollen axonal boutoms, fragmentation of neurofilaments, and oligodendrocyte abnormalities. In addition, depressive mood was observed in diabetic animals. The brain morphological alterations observed in diabetic animals could be related to brain pathologic process leading to abnormal function, cellular death, and depressive behavioral.
Neuropsychiatric Aspects of the Cerebellum
Salomé Xavier,Berta Ferreira
PsiLogos , 2012,
Abstract: The neurological functions of the cerebellum regarding the regulation of balance and movement have been known for a long time. In the last decades the cerebellum participation in cognition, emotional processes and behavior has been progressively recognized specially due to Schmahmann’s studies.The authors of the current paper will briefly review the main aspects of the cerebellum’s “classic” physiology. Afterwards, neuro-psychiatric functions and cerebellar alterations in the main psychiatric disorders - schizophrenia, bipolar disorder, major depressive disorder - will be reviewed in more detail.
Cerebellum and psychiatric disorders
Balda?ara, Leonardo;Borgio, Jo?o Guilherme Fiorani;Lacerda, Acioly Luiz Tavares de;Jackowski, Andrea Parolin;
Revista Brasileira de Psiquiatria , 2008, DOI: 10.1590/S1516-44462008000300016
Abstract: objective: the objective of this update article is to report structural and functional neuroimaging studies exploring the potential role of cerebellum in the pathophysiology of psychiatric disorders. method: a non-systematic literature review was conducted by means of medline using the following terms as a parameter: "cerebellum", "cerebellar vermis", "schizophrenia", "bipolar disorder", "depression", "anxiety disorders", "dementia" and "attention deficit hyperactivity disorder". the electronic search was done up to april 2008. discussion: structural and functional cerebellar abnormalities have been reported in many psychiatric disorders, namely schizophrenia, bipolar disorder, major depressive disorder, anxiety disorders, dementia and attention deficit hyperactivity disorder. structural magnetic resonance imaging studies have reported smaller total cerebellar and vermal volumes in schizophrenia, mood disorders and attention deficit hyperactivity disorder. functional magnetic resonance imaging studies using cognitive paradigms have shown alterations in cerebellar activity in schizophrenia, anxiety disorders and attention deficit hyperactivity disorder. in dementia, the cerebellum is affected in later stages of the disease. conclusion: contrasting with early theories, cerebellum appears to play a major role in different brain functions other than balance and motor control, including emotional regulation and cognition. future studies are clearly needed to further elucidate the role of cerebellum in both normal and pathological behavior, mood regulation, and cognitive functioning.
Neuromodulatory adaptive combination of correlation-based learning in cerebellum and reward-based learning in basal ganglia for goal-directed behavior control  [PDF]
Sakyasingha Dasgupta,Florentin W?rg?tter,Poramate Manoonpong
Frontiers in Neural Circuits , 2014, DOI: 10.3389/fncir.2014.00126
Abstract: Goal-directed decision making in biological systems is broadly based on associations between conditional and unconditional stimuli. This can be further classified as classical conditioning (correlation-based learning) and operant conditioning (reward-based learning). A number of computational and experimental studies have well established the role of the basal ganglia in reward-based learning, where as the cerebellum plays an important role in developing specific conditioned responses. Although viewed as distinct learning systems, recent animal experiments point toward their complementary role in behavioral learning, and also show the existence of substantial two-way communication between these two brain structures. Based on this notion of co-operative learning, in this paper we hypothesize that the basal ganglia and cerebellar learning systems work in parallel and interact with each other. We envision that such an interaction is influenced by reward modulated heterosynaptic plasticity (RMHP) rule at the thalamus, guiding the overall goal directed behavior. Using a recurrent neural network actor-critic model of the basal ganglia and a feed-forward correlation-based learning model of the cerebellum, we demonstrate that the RMHP rule can effectively balance the outcomes of the two learning systems. This is tested using simulated environments of increasing complexity with a four-wheeled robot in a foraging task in both static and dynamic configurations. Although modeled with a simplified level of biological abstraction, we clearly demonstrate that such a RMHP induced combinatorial learning mechanism, leads to stabler and faster learning of goal-directed behaviors, in comparison to the individual systems. Thus, in this paper we provide a computational model for adaptive combination of the basal ganglia and cerebellum learning systems by way of neuromodulated plasticity for goal-directed decision making in biological and bio-mimetic organisms.
Cerebellum and sexual behavior  [cached]
Manna Mukul
Annals of General Psychiatry , 2006, DOI: 10.1186/1744-859x-5-s1-s175
Abstract:
Migration, early axonogenesis, and Reelin-dependent layer-forming behavior of early/posterior-born Purkinje cells in the developing mouse lateral cerebellum
Takaki Miyata, Yuichi Ono, Mayumi Okamoto, Makoto Masaoka, Akira Sakakibara, Ayano Kawaguchi, Mitsuhiro Hashimoto, Masaharu Ogawa
Neural Development , 2010, DOI: 10.1186/1749-8104-5-23
Abstract: We show that Purkinje cells generated on E10.5 in the posterior periventricular region of the lateral cerebellum migrate tangentially, after only transiently migrating radially, towards the anterior, exhibiting an elongated morphology consistent with axonogenesis at E12.5. After their somata reach the outer/dorsal region by E13.5, they change 'posture' by E14.5 through remodeling of non-axon (dendrite-like) processes and a switchback-like mode of somal movement towards a superficial Reelin-rich zone, while their axon-like fibers remain relatively deep, which demarcates the somata-packed portion as a plate. In reeler cerebella, the early born posterior lateral Purkinje cells are initially normal during migration with anteriorly extended axon-like fibers until E13.5, but then fail to form the PP due to lack of the posture-change step.Previously unknown behaviors are revealed for a subset of Purkinje cells born early in the posteior lateral cerebellum: tangential migration; early axonogenesis; and Reelin-dependent reorientation initiating PP formation. This study provides a solid basis for further elucidation of Reelin's function and the mechanisms underlying the cerebellar corticogenesis, and will contribute to the understanding of how polarization of individual cells drives overall brain morphogenesis.The cerebellum plays an essential role in the coordination of posture and locomotion, head and eye movements, and a wide range of motor activities. These functions depend on the structural organization of the cerebellar cortex, in which the Purkinje cells receive input from multiple sources in the central nervous system either directly or via parallel fibers of the granule cells [1-3]. Purkinje cells are generated during the early embryonic period from the ventricular zone (VZ) facing the fourth ventricle [4,5] and migrate outward towards the pial side to subsequently form a monolayer (Purkinje cell layer) during the early postnatal days [6-10]. Just superficial to the
A single intraperitoneal injection of endotoxin in rats induces long-lasting modifications in behavior and brain protein levels of TNF-α and IL-18
Paola Bossù, Debora Cutuli, Ilaria Palladino, Paola Caporali, Francesco Angelucci, Daniela Laricchiuta, Francesca Gelfo, Paola De Bartolo, Carlo Caltagirone, Laura Petrosini
Journal of Neuroinflammation , 2012, DOI: 10.1186/1742-2094-9-101
Abstract: Wistar rats were treated with a single intraperitoneal injection of LPS (5?mg/kg) or vehicle. After 7?days and 10?months, the animal behavior was evaluated by testing specific cognitive functions, as mnesic, discriminative, and attentional functions, as well as anxiety levels. Contextually, TNF-α and IL-18 protein levels were measured by ELISA in defined brain regions (that is, frontal cortex, hippocampus, striatum, cerebellum, and hypothalamus).Behavioral testing demonstrated a specific and persistent cognitive impairment characterized by marked deficits in reacting to environment modifications, possibly linked to reduced motivational or attentional deficits. Concomitantly, LPS induced a TNF-α increase in the hippocampus and frontal cortex (from 7?days onward) and cerebellum (only at 10?months). Interestingly, LPS treatment enhanced IL-18 expression in these same areas only at 10?months after injection.Overall, these results indicate that the chronic neuroinflammatory network elicited by systemic inflammation involves a persistent participation of TNF-α accompanied by a differently regulated contribution of IL-18. This leads to speculation that, though with still unclear mechanisms, both cytokines might take part in long-lasting modifications of brain functions, including behavioral alteration.
Liponeurocytoma of the Cerebellum with Myoid Features  [PDF]
Chbani Laila, Badioui Ikram, Znati Kaoutar, Benzagmout Mohamed, Maaroufi Mustapha, Amarti Afaf
Open Journal of Pathology (OJPathology) , 2012, DOI: 10.4236/ojpathology.2012.22004
Abstract: We report an extremely rare tumor presenting with myoid features in the left cerebellum lobe in a 62-year-old man. This tumor consisted of medium to large round cells with focal lipomatous and myoid differentiation. Immunohistochemically, the tumor cells expressed synaptophysin, GFAP (glial fibrillary acidic protein) and focally desmin. From these findings, we concluded that this tumor was a liponeurocytoma with myoid features. To our knowledge, this is the second report of liponeurocytoma with myoid differentiation in the cerebellum.
Cerebellum and Ocular Motor Control  [PDF]
Amir Kheradmand,David S. Zee
Frontiers in Neurology , 2011, DOI: 10.3389/fneur.2011.00053
Abstract: An intact cerebellum is a prerequisite for optimal ocular motor performance. The cerebellum fine-tunes each of the subtypes of eye movements so they work together to bring and maintain images of objects of interest on the fovea. Here we review the major aspects of the contribution of the cerebellum to ocular motor control. The approach will be based on structural–functional correlation, combining the effects of lesions and the results from physiologic studies, with the emphasis on the cerebellar regions known to be most closely related to ocular motor function: (1) the flocculus/paraflocculus for high-frequency (brief) vestibular responses, sustained pursuit eye movements, and gaze holding, (2) the nodulus/ventral uvula for low-frequency (sustained) vestibular responses, and (3) the dorsal oculomotor vermis and its target in the posterior portion of the fastigial nucleus (the fastigial oculomotor region) for saccades and pursuit initiation.
MicroRNA Expression Profiling of the Porcine Developing Hypothalamus and Pituitary Tissue  [PDF]
Lifan Zhang,Zhaowei Cai,Shengjuan Wei,Huiyun Zhou,Hongmei Zhou,Xiaoling Jiang,Ningying Xu
International Journal of Molecular Sciences , 2013, DOI: 10.3390/ijms141020326
Abstract: MicroRNAs (miRNAs), a class of small non-coding RNA molecules, play important roles in gene expressions at transcriptional and post-transcriptional stages in mammalian brain. So far, a growing number of porcine miRNAs and their function have been identified, but little is known regarding the porcine developing hypothalamus and pituitary. In the present study, Solexa sequencing analysis showed 14,129,397 yielded reads, 6,680,678 of which were related to 674 unique miRNAs. After a microarray assay, we detected 175 unique miRNAs in the hypothalamus, including 136 previously known miRNAs and 39 novel candidates, while a total of 140 miRNAs, including 104 known and 36 new candidate miRNAs, were discovered in pituitary. More importantly, 37 and 30 differentially expressed miRNAs from several developmental stages of hypothalamus and pituitary were revealed, respectively. The 37 differentially expressed miRNAs in hypothalamus represented 6 different expression patterns, while the 30 differentially expressed miRNAs in pituitary represented 7 different expression patterns. To clarify potential target genes and specific functions of these differentially expressed miRNAs in hypothalamus and pituitary, TargetScan and Gorilla prediction tools were then applied. The current functional analysis showed that the differentially expressed miRNAs in hypothalamus and pituitary shared many biological processes, with the main differences being found in tissue-specific processes including: CDP-diacylglycerol biosynthetic/metabolic process; phosphatidic acid biosynthetic/metabolic process; energy reserve metabolic process for hypothalamus; adult behavior; sterol transport/homeostasis; and cholesterol/reverse cholesterol transport for pituitary. Overall, this study identified miRNA profiles and differentially expressed miRNAs among various developmental stages in hypothalamus and pituitary and indicated miRNA profiles change with age and brain location, enhancing our knowledge about spatial and temporal expressions of miRNAs in the porcine developing brain.
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