Molecular and Cellular Mechanisms Underlying Somatostatin-Based Signaling in Two Model Neural Networks, the Retina and the Hippocampus

Cammalleri, Maurizio; Bagnoli, Paola; Bigiani, Albertino

doi:10.3390/ijms20102506

Cited by 15 publications

(16 citation statements)

References 227 publications

(426 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, given the widespread expression of ArSS2 in A. rubens in the central nervous system and peripheral organ systems, it is likely that ArSS2 is a pleiotropic peptide and also has other roles. For example, the expression of ArSS2 by neurons in the ectoneural region of the radial nerve cords and circumoral nerve ring is indicative of roles as a neuromodulator and here parallels can be drawn with the expression of SS in subpopulations of inhibitory GABAergic neurons in cortical regions of the mammalian brain [10,11]. Furthermore, as highlighted above, the expression of ArSS2 by cells in the photoreceptor cell layer of the optic cushion in A. rubens may be indicative of roles associated with regulation of circadian activity.…”

Section: Discussionmentioning

confidence: 99%

Molecular and functional characterization of somatostatin-type signalling in a deuterostome invertebrate

Yáñez-Guerra

Egertová

et al. 2020

Open Biol.

View full text Add to dashboard Cite

Somatostatin (SS) and allatostatin-C (ASTC) are structurally and evolutionarily related neuropeptides that act as inhibitory regulators of physiological processes in mammals and insects, respectively. Here, we report the first molecular and functional characterization of SS/ASTC-type signalling in a deuterostome invertebrate—the starfish Asterias rubens (phylum Echinodermata). Two SS/ASTC-type precursors were identified in A. rubens (ArSSP1 and ArSSP2) and the structures of neuropeptides derived from these proteins (ArSS1 and ArSS2) were analysed using mass spectrometry. Pharmacological characterization of three cloned A. rubens SS/ASTC-type receptors (ArSSR1–3) revealed that ArSS2, but not ArSS1, acts as a ligand for all three receptors. Analysis of ArSS2 expression in A. rubens using mRNA in situ hybridization and immunohistochemistry revealed stained cells/fibres in the central nervous system, the digestive system (e.g. cardiac stomach) and the body wall and its appendages (e.g. tube feet). Furthermore, in vitro pharmacological tests revealed that ArSS2 causes dose-dependent relaxation of tube foot and cardiac stomach preparations, while injection of ArSS2 in vivo causes partial eversion of the cardiac stomach. Our findings provide new insights into the molecular evolution of SS/ASTC-type signalling in the animal kingdom and reveal an ancient role of SS-type neuropeptides as inhibitory regulators of muscle contractility.

show abstract

Section: Discussionmentioning

confidence: 99%

Molecular and functional characterization of somatostatin-type signalling in a deuterostome invertebrate

Yáñez-Guerra

Egertová

et al. 2020

Open Biol.

View full text Add to dashboard Cite

show abstract

“…SST 1 R are preferentially located pre-synaptically, SST 2 R and SST 4 R post-synaptically, and SST 3 R extra-synaptically. Yet, which cell type expresses the receptors and whether they are pre or postsynaptic remains unclear (Csaba and Dournaud, 2001 ; Liguz-Lecznar et al, 2016 ; Cammalleri et al, 2019 ).…”

Section: Somatostatin In the Hippocampusmentioning

confidence: 99%

Hippocampal Somatostatin Interneurons, Long-Term Synaptic Plasticity and Memory

Honoré

Khlaifia

Bosson

et al. 2021

Front. Neural Circuits

View full text Add to dashboard Cite

A distinctive feature of the hippocampal structure is the diversity of inhibitory interneurons. These complex inhibitory interconnections largely contribute to the tight modulation of hippocampal circuitry, as well as to the formation and coordination of neuronal assemblies underlying learning and memory. Inhibitory interneurons provide more than a simple transitory inhibition of hippocampal principal cells (PCs). The synaptic plasticity of inhibitory neurons provides long-lasting changes in the hippocampal network and is a key component of memory formation. The dendrite targeting interneurons expressing the peptide somatostatin (SOM) are particularly interesting in this regard because they display unique long-lasting synaptic changes leading to metaplastic regulation of hippocampal networks. In this article, we examine the actions of the neuropeptide SOM on hippocampal cells, synaptic plasticity, learning, and memory. We address the different subtypes of hippocampal SOM interneurons. We describe the long-term synaptic plasticity that takes place at the excitatory synapses of SOM interneurons, its singular induction and expression mechanisms, as well as the consequences of these changes on the hippocampal network, learning, and memory. We also review evidence that astrocytes provide cell-specific dynamic regulation of inhibition of PC dendrites by SOM interneurons. Finally, we cover how, in mouse models of Alzheimer’s disease (AD), dysfunction of plasticity of SOM interneuron excitatory synapses may also contribute to cognitive impairments in brain disorders.

show abstract

“…In contrast, gamma-aminobutyric acid (GABA) reduces somatostatin gene expression via binding to GABA A receptors [94,95]. The regulation of somatostatin expression by the GABAergic and glutamatergic system has important physiological functions, because this peptide impedes principal neurons from over-reacting by reducing their excitability and, thus, damping the rate of fire [96].…”

Section: Exogenous Factors Regulating Somatostatin Expressionmentioning

confidence: 99%

Regulatory Mechanisms of Somatostatin Expression

Ampofo

Nalbach

Menger

et al. 2020

IJMS

View full text Add to dashboard Cite

Somatostatin is a peptide hormone, which most commonly is produced by endocrine cells and the central nervous system. In mammals, somatostatin originates from pre-prosomatostatin and is processed to a shorter form, i.e., somatostatin-14, and a longer form, i.e., somatostatin-28. The two peptides repress growth hormone secretion and are involved in the regulation of glucagon and insulin synthesis in the pancreas. In recent years, the processing and secretion of somatostatin have been studied intensively. However, little attention has been paid to the regulatory mechanisms that control its expression. This review provides an up-to-date overview of these mechanisms. In particular, it focuses on the role of enhancers and silencers within the promoter region as well as on the binding of modulatory transcription factors to these elements. Moreover, it addresses extracellular factors, which trigger key signaling pathways, leading to an enhanced somatostatin expression in health and disease.

show abstract

Molecular and Cellular Mechanisms Underlying Somatostatin-Based Signaling in Two Model Neural Networks, the Retina and the Hippocampus

Cited by 15 publications

References 227 publications

Molecular and functional characterization of somatostatin-type signalling in a deuterostome invertebrate

Molecular and functional characterization of somatostatin-type signalling in a deuterostome invertebrate

Hippocampal Somatostatin Interneurons, Long-Term Synaptic Plasticity and Memory

Regulatory Mechanisms of Somatostatin Expression

Contact Info

Product

Resources

About