Open AccessEffect of endurance training on retinol‐binding protein 4 gene expression and its protein level in adipose tissue and the liver in diabetic rats induced by a high‐fat diet and streptozotocin
Author(s) -
Mansouri Masoume,
Nikooie Rohollah,
Keshtkar Abasali,
Larijani Bagher,
Omidfar Kobra
Publication year - 2014
Publication title -
journal of diabetes investigation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.089
H-Index - 50
eISSN - 2040-1124
pISSN - 2040-1116
DOI - 10.1111/jdi.12186
Subject(s) - medicine , endocrinology , adipose tissue , streptozotocin , insulin resistance , retinol binding protein , diabetes mellitus , gene expression , western blot , insulin , intraperitoneal injection , endurance training , retinol , biology , gene , vitamin , biochemistry
Aims/Introduction The present study was designed to investigate from which tissues the decrease in retinol‐binding protein 4 (RBP4) expression could contribute to the improvement of serum RBP4 and insulin resistance (IR) after endurance training. Materials and Methods Male 7‐week‐old Wistar rats were randomly assigned into four groups including control (C), trained (T), diabetic control ( DC ) and trained diabetic ( TD ). At 8 weeks‐of‐age, diabetes was induced by a high‐fat diet and intraperitoneal injection of low‐dose streptozotocin ( STZ ; 35 mg/kg). Rats in the T and TD groups carried out a 7‐week exercise program on a motorized treadmill (15–20 m/min for 20 min/day for 5 weeks), whereas the C and DC remained sedentary in their cages. Tissues gene expression and protein levels of RBP 4 were assessed by using real‐time polymerase chain reaction and western blot, respectively, while serum RBP 4 was measured using an enzyme‐linked immunosorbent assay kit. Results Exercise significantly improved IR and reduced serum concentration of RBP 4 in the TD group. This reduction of serum RBP 4 was accompanied by decreased RBP 4 protein expression in visceral fat tissue. In contrast, exercise had no significant effect on RBP 4 expression in liver and subcutaneous fat tissue in the TD group. Exercise also significantly decreased RBP 4 gene expression in visceral fat tissue and muscle, whereas the effect of exercise on liver RBP 4 messenger ribonucleic acid expression was not significant. Conclusions The present study showed that the mechanism for RBP 4 reducing the effect of endurance training could involve decreased RBP 4 messenger ribonucleic acid expression and its protein level in adipose tissue in STZ ‐induced diabetic rats.