Ghrelin deficiency in patients with type 2 diabetes: The relationships with obesity, adipose tissue dysfunction and glucose variability

Abstract

Aim: Ghrelin, a peptide hormone mostly produced by stomach, plays an important role in regulation of feeding behavior, energy balance and glucose homeostasis. The aim: to determine the relationships between fasting serum levels of ghrelin, body composition, adipose tissue endocrine function and glucose variability (GV) in type 2 diabetic subjects with and without obesity. Materials and methods: We observed 124 individuals with type 2 diabetes, including 42 non-obese subjects and 82 patients with obesity. Thirty non-obese healthy subjects were acted as control. The concentrations of ghrelin, leptin, resistin, and visfatin in the fasting serum were determined by Multiplex analysis. Body composition was assessed with DEXA. The 24-hour and nocturnal GV parameters were derived from continuous glucose monitoring. Results and discussion: Ghrelin levels in patients with diabetes were decreased significantly as compared to control (p<0.00001). Subjects with obesity demonstrated lower ghrelin concentrations then non-obese patients (p=0.002). The levels of ghrelin correlated negatively with body mass index, total and gynoid fat mass. Total fat mass was most reliable predictor of ghrelin concentration in multiple regression analysis (R2=0.18). In patients with diabetes significant increase in the levels of leptin, resistin and visfatin was revealed (all p<0.001). Ghrelin correlated negatively with resistin and visfatin levels. Positive correlations were found between ghrelin and nocturnal GV parameters: SD, Mean Amplitude of Glucose Excursions, and High Blood Glucose Index. Conclusion. The reduced fasting serum level of ghrelin is associated with obesity, adipose tissue dysfunction and nocturnal GV in subjects with type 2 diabetes.