Glial Modulation of Energy Balance: The Dorsal Vagal Complex Is No Exception

Abstract

The avoidance of being overweight or obese is a daily challenge for a growing number of people. The growing proportion of people suffering from a nutritional imbalance in many parts of the world exemplifies this challenge and emphasizes the need for a better understanding of the mechanisms that regulate nutritional balance. Until recently, research on the central regulation of food intake primarily focused on neuronal signaling, with little attention paid to the role of glial cells. Over the last few decades, our understanding of glial cells has changed dramatically. These cells are increasingly regarded as important neuronal partners, contributing not just to cerebral homeostasis, but also to cerebral signaling. Our understanding of the central regulation of energy balance is part of this (r)evolution. Evidence is accumulating that glial cells play a dynamic role in the modulation of energy balance. In the present review, we summarize recent data indicating that the multifaceted glial compartment of the brainstem dorsal vagal complex (DVC) should be considered in research aimed at identifying feeding-related processes operating at this level.

Three‐plane description of astroglial architecture and gliovascular connections of area postrema in rat: Long tanycyte connections to other parts of brainstem

“…[2010] and Troadec et al. [2022]) displays no difference from that of the border zone. The dashed line indicates the pial surface with vimentin (orange) or GFAP and aquaporin 4 (blue and green) immunopositive glial endfeet; it is also immunopositive for laminin and β‐dystroglycan.…”

“…The AP is a “sensory” circumventricular organ (CVO) like the SFO and OVLT; it participates in the control of several processes: salt and volume homeostasis and blood pressure, but in the case of AP, mainly the feeding. As a sensory CVO, it monitors the serum levels of humoral factors in the feedback mechanisms controlling these processes (for reviews, see Dallaporta et al., 2010; Jeong et al., 2021; Kaur & Ling, 2017; MacDonald et al., 2020; McKinley et al., 2003; Price et al., 2008; Sisó et al., 2010; Smith & Ferguson, 2010; Troadec et al., 2022). Besides neurons, astroglia also participates in receptor functions (Dallaporta et al., 2010; MacDonald et al., 2020; Troadec et al., 2022).…”

Glycemic challenge is associated with the rapid cellular activation of the locus ceruleus and nucleus of solitary tract: Circumscribed spatial analysis of phosphorylated MAP kinase immunoreactivity

“…It is also unclear if these are neuronal profiles; indeed, the NTS has astrocytes critical for glucosensing, counterregulatory responses and other functions [26, 27, 49] (reviewed in Ref. [195, 196]).…”

Ticking and talking in the brainstem satiety centre: Circadian timekeeping and interactions in the diet-sensitive clock of the dorsal vagal complex

“…Finally, tanycyte-like atypical ependymocytes (recently named "vagliocytes") form a specialised glial barrier between the AP and NTS. The permeability of this barrier is plastic and serves to regulate the entry of blood-borne cues into the brain parenchyma (Wang et al, 2008;Maolood and Meister, 2009;Langlet et al, 2013;Troadec et al, 2022). Thus, in contrast to the SCN for which light is a key external sensory cue, sensory cues of the internal milieu are of principal relevance to cell populations of the DVC.…”