Multiplicity of Neurosecretory Cell Types and Groups in the Brain of the Saturniid Moth Hyalophora cecropia (L.)

Viruses that infect the central nervous system (CNS) are associated with developmental abnormalities as well as neuropsychiatric and degenerative conditions. Many of these viruses such as Zika virus (ZIKV), cytomegalovirus (CMV), and herpes simplex virus (HSV) demonstrate tropism for neural stem cells (NSCs). NSCs are the multipotent progenitor cells of the brain that have the ability to form neurons, astrocytes, and oligodendrocytes. Viral infections often alter the function of NSCs, with profound impacts on the growth and repair of the brain. There are a wide spectrum of effects on NSCs, which differ by the type of virus, the model system, the cell types studied, and the age of the host. Thus, it is a challenge to predict and define the consequences of interactions between viruses and NSCs. The purpose of this review is to dissect the mechanisms by which viruses can affect survival, proliferation, and differentiation of NSCs. This review also sheds light on the contribution of key antiviral cytokines in the impairment of NSC activity during a viral infection, revealing a complex interplay between NSCs, viruses, and the immune system.

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MiR-7 in Cancer Development

Biomedicines ◽

10.3390/biomedicines9030325 ◽

2021 ◽

Vol 9 (3) ◽

pp. 325

Author(s):

Petra Korać ◽

Mariastefania Antica ◽

Maja Matulić

Keyword(s):

Cell Fate ◽

Dominant Role ◽

Tumor Development ◽

Mrna Translation ◽

Cell Types ◽

Fine Tuning ◽

Non Coding Rna ◽

Tumor Types ◽

Different Cell Types ◽

The Brain

MicroRNAs (miRNAs) are short non-coding RNA involved in the regulation of specific mRNA translation. They participate in cellular signaling circuits and can act as oncogenes in tumor development, so-called oncomirs, as well as tumor suppressors. miR-7 is an ancient miRNA involved in the fine-tuning of several signaling pathways, acting mainly as tumor suppressor. Through downregulation of PI3K and MAPK pathways, its dominant role is the suppression of proliferation and survival, stimulation of apoptosis and inhibition of migration. Besides these functions, it has numerous additional roles in the differentiation process of different cell types, protection from stress and chromatin remodulation. One of the most investigated tissues is the brain, where its downregulation is linked with glioblastoma cell proliferation. Its deregulation is found also in other tumor types, such as in liver, lung and pancreas. In some types of lung and oral carcinoma, it can act as oncomir. miR-7 roles in cell fate determination and maintenance of cell homeostasis are still to be discovered, as well as the possibilities of its use as a specific biotherapeutic.

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The Microbiota–Gut–Brain Axis and Alzheimer Disease. From Dysbiosis to Neurodegeneration: Focus on the Central Nervous System Glial Cells

Journal of Clinical Medicine ◽

10.3390/jcm10112358 ◽

2021 ◽

Vol 10 (11) ◽

pp. 2358

Author(s):

Maria Grazia Giovannini ◽

Daniele Lana ◽

Chiara Traini ◽

Maria Giuliana Vannucchi

Keyword(s):

Alzheimer Disease ◽

Glial Cells ◽

Cell Types ◽

The Past ◽

The Central Nervous System ◽

Diseased State ◽

The Brain ◽

Alzheimer Disease Pathogenesis ◽

Brain Homeostasis

The microbiota–gut system can be thought of as a single unit that interacts with the brain via the “two-way” microbiota–gut–brain axis. Through this axis, a constant interplay mediated by the several products originating from the microbiota guarantees the physiological development and shaping of the gut and the brain. In the present review will be described the modalities through which the microbiota and gut control each other, and the main microbiota products conditioning both local and brain homeostasis. Much evidence has accumulated over the past decade in favor of a significant association between dysbiosis, neuroinflammation and neurodegeneration. Presently, the pathogenetic mechanisms triggered by molecules produced by the altered microbiota, also responsible for the onset and evolution of Alzheimer disease, will be described. Our attention will be focused on the role of astrocytes and microglia. Numerous studies have progressively demonstrated how these glial cells are important to ensure an adequate environment for neuronal activity in healthy conditions. Furthermore, it is becoming evident how both cell types can mediate the onset of neuroinflammation and lead to neurodegeneration when subjected to pathological stimuli. Based on this information, the role of the major microbiota products in shifting the activation profiles of astrocytes and microglia from a healthy to a diseased state will be discussed, focusing on Alzheimer disease pathogenesis.

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Microglia in Neurodegenerative Events—An Initiator or a Significant Other?

International Journal of Molecular Sciences ◽

10.3390/ijms22115818 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5818

Author(s):

Gaylia Jean Harry

Keyword(s):

Neurovascular Unit ◽

Cell Types ◽

In Vitro Assays ◽

Significant Other ◽

Neurodegenerative Process ◽

Target Sites ◽

Systemic Factors ◽

Injury And Repair ◽

The Brain

A change in microglia structure, signaling, or function is commonly associated with neurodegeneration. This is evident in the patient population, animal models, and targeted in vitro assays. While there is a clear association, it is not evident that microglia serve as an initiator of neurodegeneration. Rather, the dynamics imply a close interaction between the various cell types and structures in the brain that orchestrate the injury and repair responses. Communication between microglia and neurons contributes to the physiological phenotype of microglia maintaining cells in a surveillance state and allows the cells to respond to events occurring in their environment. Interactions between microglia and astrocytes is not as well characterized, nor are interactions with other members of the neurovascular unit; however, given the influence of systemic factors on neuroinflammation and disease progression, such interactions likely represent significant contributes to any neurodegenerative process. In addition, they offer multiple target sites/processes by which environmental exposures could contribute to neurodegenerative disease. Thus, microglia at least play a role as a significant other with an equal partnership; however, claiming a role as an initiator of neurodegeneration remains somewhat controversial.

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Neurosecretory cell types in normal taste bud

Cellular and Molecular Life Sciences ◽

10.1007/bf01900101 ◽

1970 ◽

Vol 26 (3) ◽

pp. 289-290 ◽

Cited By ~ 9

Author(s):

C. Olivieri Sangiacomo

Keyword(s):

Neurosecretory Cell ◽

Cell Types ◽

Taste Bud ◽

Normal Taste

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Comparisons of neuroinflammation, microglial activation, and degeneration of the locus coeruleus-norepinephrine system in APP/PS1 and aging mice

Journal of Neuroinflammation ◽

10.1186/s12974-020-02054-2 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Song Cao ◽

Daniel W. Fisher ◽

Guadalupe Rodriguez ◽

Tian Yu ◽

Hongxin Dong

Keyword(s):

Spinal Cord ◽

Locus Coeruleus ◽

Microglial Activation ◽

Healthy Aging ◽

Cell Types ◽

Norepinephrine System ◽

Protective Processes ◽

The Central Nervous System ◽

Brain And Spinal Cord ◽

The Brain

Abstract Background The role of microglia in Alzheimer’s disease (AD) pathogenesis is becoming increasingly important, as activation of these cell types likely contributes to both pathological and protective processes associated with all phases of the disease. During early AD pathogenesis, one of the first areas of degeneration is the locus coeruleus (LC), which provides broad innervation of the central nervous system and facilitates norepinephrine (NE) transmission. Though the LC-NE is likely to influence microglial dynamics, it is unclear how these systems change with AD compared to otherwise healthy aging. Methods In this study, we evaluated the dynamic changes of neuroinflammation and neurodegeneration in the LC-NE system in the brain and spinal cord of APP/PS1 mice and aged WT mice using immunofluorescence and ELISA. Results Our results demonstrated increased expression of inflammatory cytokines and microglial activation observed in the cortex, hippocampus, and spinal cord of APP/PS1 compared to WT mice. LC-NE neuron and fiber loss as well as reduced norepinephrine transporter (NET) expression was more evident in APP/PS1 mice, although NE levels were similar between 12-month-old APP/PS1 and WT mice. Notably, the degree of microglial activation, LC-NE nerve fiber loss, and NET reduction in the brain and spinal cord were more severe in 12-month-old APP/PS1 compared to 12- and 24-month-old WT mice. Conclusion These results suggest that elevated neuroinflammation and microglial activation in the brain and spinal cord of APP/PS1 mice correlate with significant degeneration of the LC-NE system.

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