СHANGES OF Glut1, mTOR AND AMPK1α GENE EXPRESSION IN PANCREATIC LYMPH NODE LYMPHOCYTES OF RATS WITH EXPERIMENTAL DIABETES MELLITUS

Abstract

With the help of molecular genetic method we have investigated the level of mRNA gene expressions Glut1, mTOR and AMPK1α in PLN in pancreatic lymph nodes (PLN) of rats with streptozotocininduced diabetes mellitus (SIDM) and after administration of metformin. The levels of Glut1, mTOR and AMPK1α mRNA were determined by means of RT-PCR using CFX96™ thermocycler (Real-Time PCR Detection Systems, Bio-Rad, USA). Relative gene expression levels were calculated as ratios to GAPDH reference gene using ΔΔCt method. Statistical analysis was performed with available “Bio-Rad СFX Manager 3.1” software (Bio-Rad, USA). The mTOR+ positive lymphocytes were identified by means of monoclonal antibodies, using an indirect immunofluorescence method. Hyperglycemia was accompanied by transcriptional induction of glucose transporter Glut1 gene (9.9 to 28.9-fold, p < 0.05), and mTOR protein kinase gene (5.3 to 3.3-fold, p < 0.05) in PLN. Development of diabetes was also associated with increase by 24-34% in total mTOR+ cell numbers in PLN at the 5th week of developing diabetes (p < 0.05) and increased concentrations of rapamycin target in the immunopositive cells. Metformin administration to diabetic rats was followed by increased AMPK1α mRNA level of by 87% (p < 0,05) at the 3rd week, and 38-fold (p < 0,05), at the 5th week of SIDM development and inhibition of mTOR expression in PLN (3 to 14.7-fold, p < 0.05) accompanied by a 40 per cent decrease (p < 0.05) in total density of mTOR+ cells in PLN lymph cords of the rats following 5 weeks of SIDM.

Keywords

• streptozotocin-induced diabetes mellitus
• lymph nodes
• pancreatic
• glut1
• mtor
• ampk1α
• gene expression