Neurons and Glia Cells in Marine Invertebrates: An Update

Abstract

The nervous system (NS) of invertebrates and vertebrates is composed of two main types of cells: neurons and glia. In both types of organisms, nerve cells have similarities in biochemistry and functionality. The neurons are in charge of the synapse, and the glial cells are in charge of important functions of neuronal and homeostatic modulation. Knowing the mechanisms by which NS cells work is important in the biomedical area for the diagnosis and treatment of neurological disorders. For this reason, cellular and animal models to study the properties and characteristics of the NS are always sought. Marine invertebrates are strategic study models for the biological sciences. The sea slug Aplysia californica and the squid Loligo pealei are two examples of marine key organisms in the neurosciences field. The principal characteristic of marine invertebrates is that they have a simpler NS that consists of few and larger cells, which are well organized and have accessible structures. As well, the close phylogenetic relationship between Chordata and Echinodermata constitutes an additional advantage to use these organisms as a model for the functionality of neuronal cells and their cellular plasticity. Currently, there is great interest in analyzing the signaling processes between neurons and glial cells, both in vertebrates and in invertebrates. However, only few types of glial cells of invertebrates, mostly insects, have been studied, and it is important to consider marine organisms' research. For this reason, the objective of the review is to present an update of the most relevant information that exists around the physiology of marine invertebrate neuronal and glial cells.

The impacts of heat stress on animal cognition: Implications for adaptation to a changing climate

“…Elemental brain neurophysiology is evolutionarily conserved across invertebrates and vertebrates (Perry et al, 2013; Grillner & Robertson, 2016; Morand‐Ferron, 2017; Ortega & Olivares‐Bañuelos, 2020). Therefore, the main patterns found for the relationship between heat stress and human cognition may provide a useful reference for investigating heat stress effects on animal cognition.…”

Amphioxus neuroglia: Molecular characterization and evidence for early compartmentalization of the developing nerve cord

“…It has thus proven difficult to make useful comparisons between taxa. In addition, invertebrates are highly diverse in terms of their neural organization, and the glial cell types identified in any one group are difficult to compare with vertebrate glia (Coles, 2009; Ortega & Olivares‐Bañuelos, 2020). Supposed radial glia homologs have, however, been identified in most deuterostome taxa, which include, in addition to vertebrates, the hemichordates, echinoderms, cephalochordates and tunicates.…”

“…any one group are difficult to compare with vertebrate glia (Coles, 2009;Ortega & Olivares-Bañuelos, 2020). Supposed radial glia homologs have, however, been identified in most deuterostome taxa, which include, in addition to vertebrates, the hemichordates, echinoderms, cephalochordates and tunicates.…”

Cellular and molecular profiles of anterior nervous system regeneration in Diopatra claparedii Grube, 1878 (Annelida, Polychaeta)

“…Nervous system regeneration (NSR), or also known as neuroregeneration, is defined as restoration and regrowth of the lost neuron or nerve tissue to regain normal function. In invertebrates, such as echinoderms, the regeneration capacity is remarkable as they can regenerate both internal and external parts, including the nervous system (Ortega and Olivares-Bañuelos, 2020). Neurogenesis is a process by which a new neuron is produced from a stem/precursor cell during the developmental process from juvenile to adult.…”