Orexin A/Hypocretin Modulates Leptin Receptor-Mediated Signaling by Allosteric Modulations Mediated by the Ghrelin GHS-R1A Receptor in Hypothalamic Neurons
Overview
Neurology
Authors
Affiliations
The hypothalamus is a key integrator of nutrient-seeking signals in the form of hormones and metabolites originated in both the central nervous system and the periphery. The main autocrine and paracrine target of orexinergic-related hormones such as leptin, orexin/hypocretin, and ghrelin are neuropeptide Y neurons located in the arcuate nucleus of the hypothalamus. The aim of this study was to investigate the expression and the molecular and functional relationships between leptin, orexin/hypocretin and ghrelin receptors. Biophysical studies in a heterologous system showed physical interactions between them, with potential formation of heterotrimeric complexes. Functional assays showed robust allosteric interactions particularly different when the three receptors are expressed together. Further biochemical and pharmacological assays provided evidence of heterotrimer functional expression in primary cultures of hypothalamic neurons. These findings constitute evidence of close relationships in the action of the three hormones already starting at the receptor level in hypothalamic cells.
Raich I, Lillo J, Ferreiro-Vera C, Sanchez de Medina V, Navarro G, Franco R Int J Mol Sci. 2023; 24(24).
PMID: 38139329 PMC: 10744210. DOI: 10.3390/ijms242417500.
Grant C, Wilton A, Kaddurah-Daouk R, Skime M, Biernacka J, Mayes T Front Pharmacol. 2022; 13:984383.
PMID: 36263124 PMC: 9573988. DOI: 10.3389/fphar.2022.984383.
Orexin Signaling: A Complex, Multifaceted Process.
Dale N, Hoyer D, Jacobson L, Pfleger K, Johnstone E Front Cell Neurosci. 2022; 16:812359.
PMID: 35496914 PMC: 9044999. DOI: 10.3389/fncel.2022.812359.
Lillo J, Lillo A, Zafra D, Miralpeix C, Rivas-Santisteban R, Casals N Int J Mol Sci. 2021; 22(16).
PMID: 34445634 PMC: 8396234. DOI: 10.3390/ijms22168928.
Navarro G, Gonzalez A, Campanacci S, Rivas-Santisteban R, Reyes-Resina I, Casajuana-Martin N Comput Struct Biotechnol J. 2020; 18:2723-2732.
PMID: 33101610 PMC: 7550916. DOI: 10.1016/j.csbj.2020.09.028.