Glutamine‐induced heat shock protein protects against renal ischaemia‐reperfusion injury in rats

Abstract

To find out if a single dose of glutamine can relieve acute renal ischaemia-reperfusion injury in rats, to explore the role of heat shock protein in this process. Forty-eight Sprague-Dawley rats were assigned to four groups: saline as control group; glutamine group; quercetin (heat shock protein inhibitor) plus glutamine group; and quercetin plus saline group. The renal ischaemia-reperfusion rat model was established 1 h after drug administration. Serum creatinine (CR) and blood urea nitrogen (BUN) were analyzed. The kidneys were harvested to evaluate the degree of renal injuries. Heat shock protein expression was detected by immunohistochemistry and western blot. Cell apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay and apoptosis index was calculated. Statistical data from CR, BUN, haematoxylin-eosin (HE) dyeing and TUNEL assay results showed that ischaemia-reperfusion injury and cell apoptosis in the glutamine group were significantly milder than those in control group (P < 0.05), while ischaemia-reperfusion injury and cell apoptosis in the quercetin plus glutamine group and quercetin plus saline group were more severe than those in the control group (P < 0.05). Statistical data from immunohistochemistry and western blot results showed that heat shock protein expression was enhanced in the glutamine group compared with that in the control group (P < 0.01), while it was weaker in the quercetin plus glutamine group and quercetin plus saline group than that in the control group (P < 0.01). Our experiment suggested that a single dose of glutamine could relieve renal ischaemia-reperfusion injury in rats in 24 h, and its mechanism may be associated with enhanced heat shock protein expression. This finding may provide a new alternative for protecting against clinical renal ischaemia-reperfusion injury.