The role of acylated ghrelin and unacylated ghrelin in the blood and hypothalamus and their interaction with nonalcoholic fatty liver disease

Abstract

Objective(s): Ghrelin is a brain-gut peptide involved in substance and energy metabolism. To confirm the hypothesis that ghrelin might be involved in non-alcoholic fatty liver disease (NAFLD), a rat NAFLD model was established and the changes of ghrelin were explored.Materials and Methods: The rats were divided into control and NAFLD groups. The rats in the NAFLD group were fed a high-fat–high-cholesterol (HFHC) diet for 8 weeks. Total ghrelin (TG), acylated ghrelin (AG), unacylated ghrelin (UAG), and hypothalamic AG and its receptor GHSR-1a expression were detected using ELISA, RIA, RT-PCR, and Western blot, respectively.Results: Plasma UAG, TG, and the ratio of UAG to AG (UAG/AG) decreased, while protein and mRNA expression of hypothalamic AG and growth hormone secretagogue receptor-1a (GHSR-1a) increased in NAFLD (PConclusion: It might be that decreased circulating UAG/AG, rather than UAG or AG alone, were involved in IR and liver lipid accumulation in NAFLD. Acylated ghrelin might induce IR and promote liver lipid accumulation via a central mechanism involved in the hypothalamus.

Keywords

• ghrelin hypothalamus insulin resistance non
• alcoholic fatty liver
• disease rat