Increased glycated calmodulin in the submandibular salivary glands of streptozotocin-induced diabetic rats

Non-enzymatic glycosylation, a post translational protein modification may be implicated in the diabetes complications. Calmodulin is an important calcium binding protein that complexed with Ca2+ may be implicated in salivary gland secretory process. Glycated calmodulin has shown to be less effective in binding calcium. The aim of this study was to determine whether the concentration of glycated-calmodulin may be elevated in the submandibular salivary glands of streptozotocin-induced diabetic rats. Diabetes was induced by an interaperitoneal injection of spreptozotocin, and hyperglycemia was confirmed 72 h after injection using a glucosimeter. Thirty days after the induction of diabetes. submandibular salivary glands were used for the analysis of glycated and non-glycated calmodulin, using a glycogel B columns for separation. Glycated and non-glycated calmodulin were assayed by all enzymatic method and by ELISA. The overall concentration of CaM (non-glycated + glycated) in induced diabetic rats was significantly lower than in controls (p < 0.05). The concentration of non-glycated CaM in controls was significantly higher than in experimental group (p < 0.05), while the concentration of glycated calmodulin between these groups was statistically similar (p > 0.05). Copyright (C) 2009 John Wiley & Sons, Ltd.