scholarly journals Restricted proliferation during neurogenesis contributes to regionalization of the amphioxus nervous system.

2021 ◽  
Author(s):  
Giacomo Gattoni ◽  
Toby GR Andrews ◽  
Elia Benito Gutierrez
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Cell Division ◽  
Neural Tube ◽  
Multiple Roles ◽  
Cell Type ◽  
Hypothalamic Region ◽  
Dorsal Neural Tube ◽  
The Central Nervous System ◽  
System Differentiation

The central nervous system of the cephalochordate amphioxus consists of a dorsal neural tube with an anterior brain. Two decades of gene expression analyses in developing amphioxus embryos have shown that despite the lack of overt segmentation the amphioxus neural tube is highly regionalized at the molecular level. However, little is known about the mechanisms that generate such precise regionalization. Proliferation is a key driver of pattern formation and cell type diversification, but in amphioxus it has never been studied in detail nor in the specific context of neurogenesis. Here, we describe the dynamics of cell division during the formation of the central nervous system in amphioxus embryos and its contributions to the regionalization of the neural axis. We show that after gastrulation, proliferation pauses to become spatially restricted to the anterior and posterior ends of the neural tube at neurula stages. Only at the onset of larval life, proliferation resumes in the central part of the nervous system. By marking specific populations and inhibiting cell division during neurulation, we demonstrate that proliferation in the anterior cerebral vesicle is required to establish the full cell type repertoire of the frontal eye complex and the putative hypothalamic region of the amphioxus brain, while posterior proliferating progenitors, which were found here to derive from the dorsal lip of the blastopore, contribute to elongate the caudal floor plate. Between these proliferative domains, we find trunk nervous system differentiation is independent from cell division, which decreases during neurulation and resumes at the early larval stage. Taken together, our results highlight multiple roles for proliferation in shaping the amphioxus nervous system.

scholarly journals Adiponectin Controls Nutrient Availability in Hypothalamic Astrocytes

2021 ◽  
Vol 22 (4) ◽  
pp. 1587
Author(s):  
Nuri Song ◽  
Da Yeon Jeong ◽  
Thai Hien Tu ◽  
Byong Seo Park ◽  
Hye Rim Yang ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Adipose Tissue ◽  
Nutrient Availability ◽  
Acid Oxidation ◽  
Cell Type ◽  
Metabolic Processes ◽  
Nutrient Metabolism ◽  
Peripheral Tissues ◽  
The Central Nervous System

Adiponectin, an adipose tissue-derived hormone, plays integral roles in lipid and glucose metabolism in peripheral tissues, such as the skeletal muscle, adipose tissue, and liver. Moreover, it has also been shown to have an impact on metabolic processes in the central nervous system. Astrocytes comprise the most abundant cell type in the central nervous system and actively participate in metabolic processes between blood vessels and neurons. However, the ability of adiponectin to control nutrient metabolism in astrocytes has not yet been fully elucidated. In this study, we investigated the effects of adiponectin on multiple metabolic processes in hypothalamic astrocytes. Adiponectin enhanced glucose uptake, glycolytic processes and fatty acid oxidation in cultured primary hypothalamic astrocytes. In line with these findings, we also found that adiponectin treatment effectively enhanced synthesis and release of monocarboxylates. Overall, these data suggested that adiponectin triggers catabolic processes in astrocytes, thereby enhancing nutrient availability in the hypothalamus.

Developmental Overview of Central Neuroanatomy

2017 ◽  
Author(s):  
Peggy Mason
Keyword(s):  
Spinal Cord ◽  
Central Nervous System ◽  
Cerebrospinal Fluid ◽  
Nervous System ◽  
Cerebral Cortex ◽  
Neural Tube ◽  
The Central Nervous System ◽  
Dorsal Telencephalon ◽  
Adult Spinal Cord ◽  
The Brain

The central nervous system develops from a proliferating tube of cells and retains a tubular organization in the adult spinal cord and brain, including the forebrain. Failure of the neural tube to close at the front is lethal, whereas failure to close the tube at the back end produces spina bifida, a serious neural tube defect. Swellings in the neural tube develop into the hindbrain, midbrain, diencephalon, and telencephalon. The diencephalon sends an outpouching out of the cranium to form the retina, providing an accessible window onto the brain. The dorsal telencephalon forms the cerebral cortex, which in humans is enormously expanded by growth in every direction. Running through the embryonic neural tube is an internal lumen that becomes the cerebrospinal fluid–containing ventricular system. The effects of damage to the spinal cord and forebrain are compared with respect to impact on self and potential for improvement.

scholarly journals Zinc in the Brain: Friend or Foe?

2020 ◽  
Vol 21 (23) ◽  
pp. 8941
Author(s):  
Seunghyuk Choi ◽  
Dae Ki Hong ◽  
Bo Young Choi ◽  
Sang Won Suh
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Metal Ion ◽  
Physiological Role ◽  
Multiple Roles ◽  
Antioxidant Function ◽  
Pathophysiological Role ◽  
The Central Nervous System ◽  
Biological Component ◽  
The Brain

Zinc is a trace metal ion in the central nervous system that plays important biological roles, such as in catalysis, structure, and regulation. It contributes to antioxidant function and the proper functioning of the immune system. In view of these characteristics of zinc, it plays an important role in neurophysiology, which leads to cell growth and cell proliferation. However, after brain disease, excessively released and accumulated zinc ions cause neurotoxic damage to postsynaptic neurons. On the other hand, zinc deficiency induces degeneration and cognitive decline disorders, such as increased neuronal death and decreased learning and memory. Given the importance of balance in this context, zinc is a biological component that plays an important physiological role in the central nervous system, but a pathophysiological role in major neurological disorders. In this review, we focus on the multiple roles of zinc in the brain.

Experiments on the ‘Overgrowth’ Phenomenon in the Brain of Chick Embryos

Development ◽  
1959 ◽  
Vol 7 (2) ◽  
pp. 122-127
Author(s):  
Harry Bergquist
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Neural Tube ◽  
Human Embryos ◽  
Chick Embryos ◽  
Cranial Cavity ◽  
The Central Nervous System ◽  
The Brain ◽  
Rostral Part ◽  
Exact Term

Patten (1952) described ‘a curious distortion of the central nervous system’ in human embryos measuring 5, 7, 12·5, 20, and 30 mm. in length, as well as in some pig embryos. The malformation was called ‘overgrowth of the neural tube’. Instead of the indecisive word ‘overgrowth’ the present writer suggests the more exact term ‘hypermorphosis’ should be used for this malformation. Patten described it in the following way: ‘the neural tube epithelium had started to grow wildly so that it became folded, and refolded on itself, as if it was crowded into a cranial space fairly normal in size and shape’. The phenomenon was most distinctly developed in the rostral part of the neural tube. In some cases the cranial cavity was expanded by the process, giving rise to a high-crowned skull. In other cases an encephalocoel was formed. In later papers (1953, 1957) Patten discussed this phenomenon further.

scholarly journals The Interferon-Stimulated GeneIfi27l2aRestricts West Nile Virus Infection and Pathogenesis in a Cell-Type- and Region-Specific Manner

2015 ◽  
Vol 90 (5) ◽  
pp. 2600-2615 ◽  
Author(s):  
Tiffany M. Lucas ◽  
Justin M. Richner ◽  
Michael S. Diamond
Keyword(s):  
Spinal Cord ◽  
Central Nervous System ◽  
Cell Culture ◽  
Nervous System ◽  
West Nile Virus ◽  
Cell Type ◽  
West Nile ◽  
Specific Manner ◽  
A Cell ◽  
The Central Nervous System

ABSTRACTThe mammalian host responds to viral infections by inducing expression of hundreds of interferon-stimulated genes (ISGs). While the functional significance of many ISGs has yet to be determined, their cell type and temporal nature of expression suggest unique activities against specific pathogens. Using a combination of ectopic expression and gene silencing approaches in cell culture, we previously identifiedIfi27l2aas a candidate antiviral ISG within neuronal subsets of the central nervous system (CNS) that restricts infection by West Nile virus (WNV), an encephalitic flavivirus of global concern. To investigate the physiological relevance of Ifi27l2a in the context of viral infection, we generatedIfi27l2a−/−mice. Although adult mice lackingIfi27l2awere more vulnerable to lethal WNV infection, the viral burden was greater only within the CNS, particularly in the brain stem, cerebellum, and spinal cord. Within neurons of the cerebellum and brain stem, in the context of WNV infection, a deficiency of Ifi27l2a was associated with less cell death, which likely contributed to sustained viral replication and higher titers in these regions. Infection studies in a primary cell culture revealed thatIfi27l2a−/−cerebellar granule cell neurons and macrophages but not cerebral cortical neurons, embryonic fibroblasts, or dendritic cells sustained higher levels of WNV infection than wild-type cells and that this difference was greater under conditions of beta interferon (IFN-β) pretreatment. Collectively, these findings suggest that Ifi27l2a has an antiviral phenotype in subsets of cells and that at least some ISGs have specific inhibitory functions in restricted tissues.IMPORTANCEThe interferon-stimulatedIfi27l2agene is expressed differentially within the central nervous system upon interferon stimulation or viral infection. Prior studies in cell culture suggested an antiviral role for Ifi27l2a during infection by West Nile virus (WNV). To characterize its antiviral activityin vivo, we generated mice with a targeted gene deletion ofIfi27l2a. Based on extensive virological analyses, we determined that Ifi27l2a protects mice from WNV-induced mortality by contributing to the control of infection of the hindbrain and spinal cord, possibly by regulating cell death of neurons. This antiviral activity was validated in granule cell neurons derived from the cerebellum and in macrophages but was not observed in other cell types. Collectively, these data suggest that Ifi27l2a contributes to innate immune restriction of WNV in a cell-type- and tissue-specific manner.

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