Adrenergic regulation of immune cell function and inflammation
- PDF / 361,028 Bytes
- 9 Pages / 595.276 x 790.866 pts Page_size
- 96 Downloads / 189 Views
REVIEW
Adrenergic regulation of immune cell function and inflammation Drashya Sharma 1 & J. David Farrar 1 Received: 5 November 2020 / Accepted: 14 November 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract The sympathetic nervous system integrates the functions of multiple organ systems by regulating their autonomic physiological activities. The immune system is regulated both locally and systemically by the neurotransmitters epinephrine and norepinephrine secreted by the adrenal gland and local sympathetic neurons. Immune cells respond by activation of adrenergic receptors, primarily the β2-adrenergic receptor, which signal through heterotrimeric G-proteins. Depending upon the cell type, adrenergic signaling regulates a variety of functions in immune cells ranging from cellular migration to cytokine secretion. Furthermore, due to the diurnal oscillation of systemic norepinephrine levels, various immune functions follow a circadian rhythmic pattern. This review will highlight recent advances in our understanding of how the sympathetic nervous system regulates both innate and adaptive immune functions and how this regulation is linked to circadian rhythms.
Systemic pathways of adrenergic regulation The sympathetic nervous system controls a myriad of biological processes, and, perhaps, the most well-studied regulators of this system are the neurotransmitters epinephrine (E) and norepinephrine (NE). They both bind and signal through the adrenergic class of G-protein-coupled receptors whose members are differentially expressed on various cells and tissues throughout the body. The receptors are divided into α- and βfamily members, and their selective expression, coupled to unique G-α downstream second messengers, conveys unique signals to individual cell types. In this way, E and NE can simultaneously regulate distinct functions in many organ systems. The immune system is intimately connected to the sympathetic nervous system [1]. Early studies demonstrated that both primary and secondary lymphoid tissues are innervated by post-ganglionic sympathetic nerve fibers that predominantly secrete NE as their primary neurotransmitter [2–12]. Immune cells come in direct contact with the dendrites of these neurons. Both innate and adaptive immune cells express
This article is a contribution to the special issue on: Neuro-immune Interactions - Guest Editor: David Farrar * J. David Farrar [email protected] 1
Department of Immunology, UT Southwestern Medical Center, Dallas, TX, USA
adrenergic receptors, primarily the β2-adrenergic receptor (ADRB2), enabling them to directly respond to the sympathetic nervous system [12]. Sympathetic nerves secrete NE in response to pathogenic organisms (reviewed in [12]). While signaling through pattern recognition receptors (PRRs) promotes inflammatory cytokine secretion from antigen-presenting cells, neurons themselves express various Toll-like receptors (TLRs), enabling them to respond directly to certain pathogen-associated molecular patterns (PAMPs)
Data Loading...
