Glucagon-Like Peptide-1-, but not Growth and Differentiation Factor 15-, Receptor Activation Increases the Number of Interleukin-6-Expressing Cells in the External Lateral Parabrachial Nucleus

Abstract

List of non-standard abbreviations CGRP-calcitonin gene related peptide Ex4-exendin-4 GDF15-growth and differentiation factor 15 GFRAL-GDNF family receptor alpha-like GLP-1-glucagon like peptide 1 GLP-1R-glucagon like peptide 1 receptor IL-6Rα-interleukin-6 receptor alpha MIC1-macrophage inhibitory cytokine 1 NTS-nucleus of the solitary tract PBN-parabrachial nucleus PBNel-external lateral parabrachial nucleus RFP-red fluorescent protein STAT3-signal transducer and activator of transcription 3

Interleukin‐6 in the central amygdala is bioactive and co‐localised with glucagon‐like peptide‐1 receptor

“…The mKATE2 reporter staining reflects IL‐6 expression, as supported by mKATE2 staining being co‐localised with IL‐6 mRNA, which was identified by RNAscope. Moreover, the mKATE2 reporter staining co‐localised with the staining obtained by an anti‐IL‐6 antibody, which, as shown by ourselves (see Supporting information, Figure S1), as well in previous studies,by others demonstrated less staining in different strains of IL‐6 gene knockout mice…”

“…In the present study, we used RedIL6, an IL‐6 reporter mouse that was described recently . Briefly, the RedI6 reporter mouse was generated according to a gene knock‐in protocol.…”

“…Twelve‐week‐old male and female RedIL6 strain mice were used to visualise IL‐6. Full details on this strain have been provided previously …”

“…Cartoons in Figures 1A,B and 3A,B are adapted from Paxinos and Franklin . For IL‐6 staining in GLP‐1R and GLP‐1 (Venus) reporter mice, a previously validated IL‐6 antibody was used. Confirmation that this antibody shows markedly less staining also in the amygdala of RedIL6 homozygous mice is provided in the Supporting information (Figure S1).…”

GLP-1 physiology informs the pharmacotherapy of obesity

“…A potential role for cytokine signaling in the transduction of anorectic GLP-1 signals has also been suggested. Co-localization of interleukin-6 (IL-6) and GLP1R+ cells has been detected in the hypothalamus, brainstem, and the lateral parabrachial nucleus, and administration of exendin-4 increased the proportion of IL-6+ cells in the external parabrachial nucleus [ 26 ]. Acute intracerebroventricular (ICV) injection of exendin-4 also increased the expression of IL-6 in the brainstem, and of IL-6 and IL-1β in the rat hypothalamus.…”