Transiently Nav1.8-expressing neurons are capable of sensing noxious stimuli in the brain

Helia Tenza-Ferrer; Mélcar Collodetti; Eduardo de Souza Nicolau; Alexander Birbrair; Luiz Alexandre Viana Magno; Marco Aurélio Romano-Silva

doi:10.3389/fncel.2022.933874

Transiently Nav1.8-expressing neurons are capable of sensing noxious stimuli in the brain

Front Cell Neurosci. 2022 Aug 29:16:933874. doi: 10.3389/fncel.2022.933874. eCollection 2022.

Authors

Helia Tenza-Ferrer¹, Mélcar Collodetti¹, Eduardo de Souza Nicolau¹, Alexander Birbrair^{2

3

4}, Luiz Alexandre Viana Magno^{1

5

6}, Marco Aurélio Romano-Silva^{1

7}

Affiliations

¹ Centro de Tecnologia em Medicina Molecular, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil.
² Departamento de Patologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil.
³ Department of Dermatology, University of Wisconsin-Madison, Madison, WI, United States.
⁴ Department of Radiology, Columbia University Medical Center, New York, NY, United States.
⁵ Curso de Medicina, Universidade José do Rosário Vellano (UNIFENAS), Belo Horizonte, Brazil.
⁶ Pós-graduação da Faculdade Ciências Médicas de Minas Gerais, Belo Horizonte, Brazil.
⁷ Departamento de Saúde Mental, Faculdade de Medicina, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil.

Abstract

While current research highlights the role of Nav1. 8 sensory neurons from the peripheral nervous system, the anatomical and physiological characterization of encephalic Nav1.8 neurons remains unknown. Here, we use a Cre/fluorescent reporter mouse driven by the Nav1.8 gene promoter to reveal unexpected subpopulations of transiently-expressing Nav1.8 neurons within the limbic circuitry, a key mediator of the emotional component of pain. We observed that Nav1.8 neurons from the bed nuclei of the stria terminalis (BST), amygdala, and the periaqueductal gray (vPAG) are sensitive to noxious stimuli from an experimental model of chronic inflammatory pain. These findings identify a novel role for central Nav1.8 neurons in sensing nociception, which could be researched as a new approach to treating pain disorders.

Keywords: Nav1.8; amygdala; cFOS; central nervous system; inflammatory pain; limbic circuitry; neurocircuit; neurons.