Differential Effects of a Full and Biased Ghrelin Receptor Agonist in a Mouse Kindling Model

oleh: An Buckinx, Yana Van Den Herrewegen, Anouk Pierre, Eleonora Cottone, Khoubaib Ben Haj Salah, Jean-Alain Fehrentz, Ron Kooijman, Dimitri De Bundel, Ilse Smolders

Format: Article
Diterbitkan: MDPI AG 2019-05-01

Deskripsi

The ghrelin system has received substantial recognition as a potential target for novel anti-seizure drugs. Ghrelin receptor (ghrelin-R) signaling is complex, involving G&#945;<sub>q/11</sub>, G&#945;<sub>i/o</sub>, G&#945;<sub>12/13</sub>, and &#946;-arrestin pathways. In this study, we aimed to deepen our understanding regarding signaling pathways downstream the ghrelin-R responsible for mediating anticonvulsive effects in a kindling model. Mice were administered the proconvulsive dopamine 1 receptor-agonist, SKF81297, to gradually induce a kindled state. Prior to every SKF81297 injection, mice were treated with a ghrelin-R full agonist (JMV-1843), a G&#945;<sub>q</sub> and G&#945;<sub>12</sub> biased ligand unable to recruit &#946;-arrestin (YIL781), a ghrelin-R antagonist (JMV-2959), or saline. Mice treated with JMV-1843 had fewer and less severe seizures compared to saline-treated controls, while mice treated with YIL781 experienced longer and more severe seizures. JMV-2959 treatment did not lead to differences in seizure severity and number. Altogether, these results indicate that the G&#945;<sub>q</sub> or G&#945;<sub>12</sub> signaling pathways are not responsible for mediating JMV-1843&#8242;s anticonvulsive effects and suggest a possible involvement of &#946;-arrestin signaling in the anticonvulsive effects mediated by ghrelin-R modulation.