Changes in obestatin gene and GPR39 receptor expression in peripheral tissues of rat models of obesity, type 1 and type 2 diabetes.
BACKGROUND
Obestatin has a role in regulating food intake and energy expenditure, but the roles of obestatin and the GPR39 receptor in obesity and type 1 and type 2 diabetes mellitus (T1DM and T2DM, respectively) are not well understood. The aim of the present study was to investigate changes in obestatin and GPR39 in pathophysiological conditions like obesity, T1DM, and T2DM.


METHODS
Using rat models of diet-induced obesity (DIO), T1DM and T2DM (n = 14 per group), obestatin, its precursor protein preproghrelin, and GPR39 expression was investigated in tissues involved in glucose and lipid homeostasis regulation. Furthermore, serum obestatin and ghrelin concentrations were determined.


RESULTS
Serum obestatin concentrations were positively correlated with glucagon (r = 0.6456; P < 0.001) and visfatin (r = 0.5560; P < 0.001), and negatively correlated with insulin (r = -0.4362; P < 0.05), adiponectin (r = -0.3998; P < 0.05), and leptin (r = -0.4180; P < 0.05). There were differences in GPR39 and preproghrelin expression in the three animal models. Hepatic GPR39 and preproghrelin mRNA expression was greater in T1DM, T2DM, and obese rats than in lean controls, whereas pancreatic GPR39 mRNA and protein and preproghrelin mRNA expression was decreased in T1DM, T2DM, and DIO rats. Higher GPR39 and preproghrelin protein and mRNA levels were found in adipose tissues of T1DM compared with control. In adipose tissues of T2DM and DIO rats, GPR39 protein levels were lower than in lean or T1DM rats. Preproghrelin mRNA was higher in adipose tissues of T1DM, T2DM, and DIO than lean rats.


CONCLUSIONS
We hypothesize that changes in obestatin, GPR39, and ghrelin may contribute to metabolic abnormalities in T1DM, T2DM, and obesity.
Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Poznan, Poland.|Department of Hepatology and Gastroenterology and the Interdisciplinary Centre of Metabolism: Endocrinology, Diabetes and Metabolism, Charité-University Medicine Berlin, Berlin, Germany.
Pawel Antoni
PA
Kolodziejski
Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Poznan, Poland.
Ewa
E
Pruszynska-Oszmalek
Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Poznan, Poland.
Maciej
M
Sassek
Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Poznan, Poland.
Przemyslaw
P
Kaczmarek
Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Poznan, Poland.
Dawid
D
Szczepankiewicz
Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Poznan, Poland.
Maria
M
Billert
Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Poznan, Poland.
Paweł
P
Mackowiak
Department of Hepatology and Gastroenterology and the Interdisciplinary Centre of Metabolism: Endocrinology, Diabetes and Metabolism, Charité-University Medicine Berlin, Berlin, Germany.|Medical Clinic 1, Department of Gastroenterology, Elblandklinik, Meissen, Germany.
Mathias Z
MZ
Strowski
Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Poznan, Poland.
Krzysztof W
KW
Nowak
D000704:Analysis of Variance; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D015153:Blotting, Western; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000503:physiopathology*; D015870:Gene Expression; D054439:Ghrelin / Q000097:blood / Q000235:genetics / Q000378:metabolism; D005934:Glucagon / Q000097:blood; D007328:Insulin / Q000097:blood; D008297:Male; D009765:Obesity / Q000097:blood / Q000503:physiopathology*; D036361:Peptide Hormones / Q000097:blood / Q000235:genetics* / Q000378:metabolism; D017208:Rats, Wistar; D043562:Receptors, G-Protein-Coupled / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014280:Triglycerides / Q000097:blood
D001786:Blood Glucose; C535178:GPR39 protein, rat; D054439:Ghrelin; D007328:Insulin; D036361:Peptide Hormones; D043562:Receptors, G-Protein-Coupled; D014280:Triglycerides; C505798:obestatin, rat; D005934:Glucagon
1型糖尿病; 2型糖尿病; GPR39; diet-induced obesity; obestatin; type 1 diabetes mellitus; type 2 diabetes mellitus; 肥胖抑制素; 饮食诱导的肥胖