MITOCHONDRIAL FUNCTION AND INSULIN SIGNALLING ARE LOWERED BY SUSTAINED ACYLATED GHRELIN TREATMENT IN RAT ADIPOSE TISSUE

Acylated ghrelin (AG), a gastric orexigenic hormone which plays a relevant role in the regulation of intermediate metabolism, has shown tissue specific effects. In skeletal muscle, both in vitro and in healthy and diseased rodent models experiments show that AG enhances mitochondrial function and insulin signalling, with variable effect in reducing tissue inflammation and redox balance. In the liver, AG improves redox state and gluconeogenesis, limits fat accumulation and reduces insulin signalling with no changes in mitochondrial function. AG effects on adipose tissue metabolism are currently largely undefined. We investigated the impact of four days AG s.c. administration in 12-week-old male healthy Wistar rats (AGT; n=8; twice-a-day 200 ng s.c. non orexigenic dose) compared to vehicle (Con; n=8) on retroperitoneal adipose tissue (AT) mitochondrial enzyme activities (citrate synthase and cytochrome c oxidase), oxidized/total glutathione, cytokine levels (xMAP) and insulin sensitivity in terms of AKT and GSK activating phosphorilation (western blot). No differences were observed among between groups in cumulative food intake or body weight. AGT had lower (p