The effect of candesartan on chronic stress induced imbalance of glucose homeostasis

Abstract

Objective: To explore whether chronic stress induces imbalance of glucose homeostasis, and to investigate the possible involvement of the renin-angiotensin system (RAS). Methods: Male Sprague-Dawley rats were divided into four groups: control, chronic stress, chronic stress plus low dose candesartan (an angiotensin II receptor-1 blocker, ARB, 5 mg/kg/d, i.p.), chronic stress plus high dose candesartan (15 mg/kg/d, i.p.). Rats were received restraint stress for 14 days. Glucose transporter 2 (GLUT2) mRNA was quantified in liver by real-time polymerase chain reaction. The concentration of glucokinase (GK), glucose-6-phosphatase (G-6-P), glycogen synthase (GS), insulin receptor (ISR), glucocorticoid receptor (GR)-alpha and -beta in liver, hexokinase (HK), lactate dehydrogenase (LDH) and succinate dehydrogenase (SDH) in muscle, and serum insulin were measured by ELISA. Body weights, systolic blood pressure, heart rate and fasting blood glucose were monitored. Glucose tolerance test were performed after 14 days restraint stress. Results: After 14 days restraint stress, systolic blood pressure, increase of plasma glucose concentration at 15 minutes were higher and the fasting plasma concentration of glucose was lower compared with control group (P < 0.05), which were reversed by high dose ARB treatment (P < 0.05). In addition, chronic stress decreased expression of GLUT2 and increased expression of GR beta in liver. High dose ARB treatment normalized GLUT2 and GR beta expressions in liver. Conclusions: Our present data indicate chronic stress induces the imbalance of glucose homeostasis and RAS contributes to the imbalance of glucose homeostasis induced by chronic stress.

Keywords

• glucose metabolism
• restraint stress
• renin-angiotensin-system (RAS)
• angiotensin II receptor-1 blocker (ARB)