Glycation of the Masticatory Mucosal Collagen in Experimental Diabetic Rats

Abstract

The glycation levels were investigated in collagen extracted from masticatory mucosa of streptozotocin-induced diabetic and age-matched control rats in order to elucidate the nonenzymatic glycation, referred to as the Maillard reaction, in the collagen of diabetic animals. Early-stage products of the Maillard reaction were measured by furosine, which is an acid hydrolysis product derived from fructose-lysine. Late-stage products of the Maillard reaction were measured with fluorescence as an indicator.
The total hydroxyproline in the masticatory mucosa of diabetic rats decreased relative to the controls. Furthermore, solubilization of the collagen by pepsin and the type III/I ratio of collagen decreased in the diabetic rats. Furosine levels did not correlate with serum glucose levels, and no difference was seen between the two groups in the level of furosine. Although the fluorescence intensity in the controls did not correlate with serum glucose levels, they did in the diabetic group. The fluorescence intensity in the diabetic animals increased relative to that in the controls.
These findings suggest that the effects of the high serum glucose level extend to the collagen which makes up the extracellular matrix of the masticatory mucosa. The apparent acceleration of high glycosylated collagen in diabetes may contributed to the development of cross-linkage in collagen.