Glutamine enhances the heat shock protein 70 expression as a cardioprotective mechanism in left heart tissues in the presence of diabetes mellitus.

Objective: Effects of diabetes mellitus on myocardium were investigated, by assessing levels of heat shock protein (HSP) 70, and efficacy of glutamine was tested.

Materials And Methods: Thirty male rats were divided into three groups: control group (Group 1), diabetic group (Group 2) and glutamine-induced diabetic group (Group 3). Diabetes was created by intravenous streptozocin injection. Rats were examined one month later for cardiac complications of diabetes. Serum and tissue samples were obtained to measure HSP 70 levels.

Results: Following streptozocin administration, glucose levels increased markedly. This resulted in a significant increase in HSP 70 in serum and tissues. When Group 3 was compared with other groups, HSP 70 was more increased in serum and tissues. When Groups 2 and 3 were compared, more increased HSP 70 values were observed in Group 3, statistical significance was obtained for left atrial and left ventricular HSP 70 levels. Elevated blood glucose was correlated with elevated HSP 70 levels. Increased serum HSP 70 levels were correlated with tissue HSP 70 values.

Conclusions: HSP 70 levels increase in the myocardium of rats in diabetes mellitus as a protective mechanism. Levels of HSP 70 may further be increased with parenteral administration of glutamine. Efficacy of glutamine is more pronounced in left heart structures.