scholarly journals The (Real) Neurogenic/Gliogenic Potential of the Postnatal and Adult Brain Parenchyma

2013 ◽  
Vol 2013 ◽  
pp. 1-14 ◽  
Author(s):  
Luca Bonfanti

During the last two decades basic research in neuroscience has remarkably expanded due to the discovery of neural stem cells (NSCs) and adult neurogenesis in the mammalian central nervous system (CNS). The existence of such unexpected plasticity triggered hopes for alternative approaches to brain repair, yet deeper investigation showed that constitutive mammalian neurogenesis is restricted to two small “neurogenic sites” hosting NSCs as remnants of embryonic germinal layers and subserving homeostatic roles in specific neural systems. The fact that in other classes of vertebrates adult neurogenesis is widespread in the CNS and useful for brain repair sometimes creates misunderstandings about the real reparative potential in mammals. Nevertheless, in the mammalian CNS parenchyma, which is commonly considered as “nonneurogenic,” some processes of gliogenesis and, to a lesser extent, neurogenesis also occur. This “parenchymal” cell genesis is highly heterogeneous as to the position, identity, and fate of the progenitors. In addition, even the regional outcomes are different. In this paper the heterogeneity of mammalian parenchymal neurogliogenesis will be addressed, also discussing the most common pitfalls and misunderstandings of this growing and promising research field.

2020 ◽  
Vol 3 (2) ◽  
pp. 216-242 ◽  
Author(s):  
Mayuri Shukla ◽  
Areechun Sotthibundhu ◽  
Piyarat Govitrapong

The revelation of adult brain exhibiting neurogenesis has established that the brain possesses great plasticity and that neurons could be spawned in the neurogenic zones where hippocampal adult neurogenesis attributes to learning and memory processes. With strong implications in brain functional homeostasis, aging and cognition, various aspects of adult neurogenesis reveal exuberant mechanistic associations thereby further aiding in facilitating the therapeutic approaches regarding the development of neurodegenerative processes in Alzheimer’s Disease (AD). Impaired neurogenesis has been significantly evident in AD with compromised hippocampal function and cognitive deficits. Melatonin the pineal indolamine augments neurogenesis and has been linked to AD development as its levels are compromised with disease progression. Here, in this review, we discuss and appraise the mechanisms via which melatonin regulates neurogenesis in pathophysiological conditions which would unravel the molecular basis in such conditions and its role in endogenous brain repair. Also, its components as key regulators of neural stem and progenitor cell proliferation and differentiation in the embryonic and adult brain would aid in accentuating the therapeutic implications of this indoleamine in line of prevention and treatment of AD.   


2021 ◽  
Vol 22 (14) ◽  
pp. 7450
Author(s):  
Citlalli Netzahualcoyotzi ◽  
Luis Miguel Rodríguez-Serrano ◽  
María Elena Chávez-Hernández ◽  
Mario Humberto Buenrostro-Jáuregui

The endocannabinoid system (ECS) is a crucial modulatory system in which interest has been increasing, particularly regarding the regulation of behavior and neuroplasticity. The adolescent–young adulthood phase of development comprises a critical period in the maturation of the nervous system and the ECS. Neurogenesis occurs in discrete regions of the adult brain, and this process is linked to the modulation of some behaviors. Since marijuana (cannabis) is the most consumed illegal drug globally and the highest consumption rate is observed during adolescence, it is of particular importance to understand the effects of ECS modulation in these early stages of adulthood. Thus, in this article, we sought to summarize recent evidence demonstrating the role of the ECS and exogenous cannabinoid consumption in the adolescent–young adulthood period; elucidate the effects of exogenous cannabinoid consumption on adult neurogenesis; and describe some essential and adaptive behaviors, such as stress, anxiety, learning, and memory. The data summarized in this work highlight the relevance of maintaining balance in the endocannabinoid modulatory system in the early and adult stages of life. Any ECS disturbance may induce significant modifications in the genesis of new neurons and may consequently modify behavioral outcomes.


2008 ◽  
Vol 363 (1500) ◽  
pp. 2111-2122 ◽  
Author(s):  
Hideyuki Okano ◽  
Kazunobu Sawamoto

Recent advances in stem cell research, including the selective expansion of neural stem cells (NSCs) in vitro , the induction of particular neural cells from embryonic stem cells in vitro , the identification of NSCs or NSC-like cells in the adult brain and the detection of neurogenesis in the adult brain (adult neurogenesis), have laid the groundwork for the development of novel therapies aimed at inducing regeneration in the damaged central nervous system (CNS). There are two major strategies for inducing regeneration in the damaged CNS: (i) activation of the endogenous regenerative capacity and (ii) cell transplantation therapy. In this review, we summarize the recent findings from our group and others on NSCs, with respect to their role in insult-induced neurogenesis (activation of adult NSCs, proliferation of transit-amplifying cells, migration of neuroblasts and survival and maturation of the newborn neurons), and implications for therapeutic interventions, together with tactics for using cell transplantation therapy to treat the damaged CNS.


2013 ◽  
Vol 111 (4) ◽  
pp. 755-755
Author(s):  
Marianne A. Yon ◽  
Suzanna L. Mauger ◽  
Lucy C. Pickavance

Of the environmental factors which have an impact on body weight, nutrients are most influential. Within normal limits, hypothalamic and related neuronal populations correct perturbations in energy metabolism, to return the body to its nutritional set-point, either through direct response to nutrients or indirectly via peripheral appetite signals. Excessive intake of certain macronutrients, such as simple carbohydrates and SFA, can lead to obesity and attendant metabolic dysfunction, also reflected in alterations in structural plasticity, and, intriguingly, neurogenesis, in some of these brain regions. Neurogenesis, previously thought to occur only in the embryo, is now known to take place in the adult brain, dependent on numerous stimulating and inhibiting factors, including dietary components. Because of classic associations between neurogenesis and the hippocampus, in learning and cognition, this brain region has also been the focus of attention in the study of links between diet and neurogenesis. Recently, however, a more complete picture of this relationship has been building: not only has the hypothalamus been shown to satisfy the criteria for a neurogenic niche, but appetite-related mediators, including circulating hormones, such as leptin and ghrelin, pro-inflammatory cytokines and the endocannabinoid intracellular messengers, are also being examined for their potential role in mediating neurogenic responses to macronutrients. The present review draws together these observations and investigates whether n-3 PUFA may exert their attenuating effects on body weight through the stimulation of adult neurogenesis. Exploration of the effects of nutraceuticals on neurogenic brain regions may encourage the development of new rational therapies in the fight against obesity.


2001 ◽  
Vol 79 (4) ◽  
pp. 297-302 ◽  
Author(s):  
R Boonstra ◽  
L Galea ◽  
S Matthews ◽  
J M Wojtowicz

The dogma that the adult brain produces no new neurons has been overturned, but the critics are still asking, so what? Is adult neurogenesis a biologically relevant phenomenon, or is it perhaps harmful because it disrupts the existing neuronal circuitry? Considering that the phenomenon is evolutionarily conserved in all mammalian species examined to date and that its relevance has been well documented in non-mammalian species, it seems self-evident that neurogenesis in adult mammals must have a role. In birds, it has been established that neurogenesis varies dramatically with seasonal changes in song production. In chickadees, the learning behaviour related to finding stored food is also correlated with seasonal adult neurogenesis. Such studies are still nonexistent in mammals, but the related evidence suggests that neurogenesis does vary seasonally in hamsters and shows sexual differences in meadow voles. To promote studies on natural populations asking fundamental questions of the purpose and function of neurogenesis, we organized a Workshop on "Hippocampal Neurogenesis in Natural Populations" in Toronto in May 2000. The Workshop highlighted recent discoveries in neurogenesis from the lab, and focused on its functional consequences. The consensus at the Workshop was that demonstration of a role for neurogenesis in natural behaviours will ultimately be essential if we are to understand the purpose and function of neurogenesis in humans.Key words: neurogenesis, hippocampus, dentate gyrus, learning, memory, wild population.


2014 ◽  
Vol 1073-1076 ◽  
pp. 2734-2739
Author(s):  
Zhi Yong Tian ◽  
Feng Zheng

Research on order quantity plays an important role in logistics and supply chain (SC) whether for traditional economy objective or for low carbon objective. The paper summarizes the research framework of economic order quantity (EOQ) in brief. It also introduces and reviews the new research field carbon footprint order quantity (COQ). Comparing with the research of EOQ, it finds that the research on COQ is just beginning and the research assumptions still remain at the case of the “Square Root” era of EOQ a century ago. Based on some related literatures, the paper analyzes the effect of low carbon on social economy especially some influence factors related to order quantity. And it refers some important market forces affected by low carbon that are ignored by the literatures of COQ currently. Then the paper purposes the basic research approach of COQ. Finally, it provides several important topics of COQ for further research.


Author(s):  
Emmanuel Buabin

The objective is intelligent recommender system classification unit design using hybrid neural techniques. In particular, a neuroscience-based hybrid neural by Buabin (2011a) is introduced, explained, and examined for its potential in real world text document classification on the modapte version of the Reuters news text corpus. The so described neuroscience model (termed Hy-RNC) is fully integrated with a novel boosting algorithm to augment text document classification purposes. Hy-RNC outperforms existing works and opens up an entirely new research field in the area of machine learning. The main contribution of this book chapter is the provision of a step-by-step approach to modeling the hybrid system using underlying concepts such as boosting algorithms, recurrent neural networks, and hybrid neural systems. Results attained in the experiments show impressive performance by the hybrid neural classifier even with a minimal number of neurons in constituting structures.


2013 ◽  
pp. 2164-2175
Author(s):  
Fakhreddine Ababsa ◽  
Iman Maissa Zendjebil ◽  
Jean-Yves Didier

The concept of Mixed Reality (MR) aims at completing our perception of the real world, by adding fictitious elements that are not perceptible naturally such as: computer generated images, virtual objects, texts, symbols, graphics, sounds, smells, et cetera. One of the major challenges for efficient Mixed Reality system is to ensure the spatiotemporal coherence of the augmented scene between the virtual and the real objects. The quality of the Real/Virtual registration depends mainly on the accuracy of the 3D camera pose estimation. The goal of this chapter is to provide an overview on the recent multi-sensor fusion approaches used in Mixed Reality systems for the 3D camera tracking. We describe the main sensors used in those approaches and we detail the issues surrounding their use (calibration process, fusion strategies, etc.). We include the description of some Mixed Reality techniques developed these last years and which use multi-sensor technology. Finally, we highlight new directions and open problems in this research field.


Complexity ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-15 ◽  
Author(s):  
Hanwen Liu ◽  
Huaizhen Kou ◽  
Chao Yan ◽  
Lianyong Qi

Nowadays, scholar recommender systems often recommend academic papers based on users’ personalized retrieval demands. Typically, a recommender system analyzes the keywords typed by a user and then returns his or her preferred papers, in an efficient and economic manner. In practice, one paper often contains partial keywords that a user is interested in. Therefore, the recommender system needs to return the user a set of papers that collectively covers all the queried keywords. However, existing recommender systems only use the exact keyword matching technique for recommendation decisions, while neglecting the correlation relationships among different papers. As a consequence, it may output a set of papers from multiple disciplines that are different from the user’s real research field. In view of this shortcoming, we propose a keyword-driven and popularity-aware paper recommendation approach based on an undirected paper citation graph, named PRkeyword+pop. At last, we conduct large-scale experiments on the real-life Hep-Th dataset to further demonstrate the usefulness and feasibility of PRkeyword+pop. Experimental results prove the advantages of PRkeyword+pop in searching for a set of satisfactory papers compared with other competitive approaches.


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