Amylase and cyclic amp receptor protein expression in human diabetic parotid glands.
BACKGROUND
Salivary dysfunction and oral disorders have been described in both type 1 and type 2 diabetes mellitus. However, the cellular and molecular consequences of diabetes on oral tissues remain to be ascertained. The purpose of this investigation was to study, by means of electron microscopy, the morphologic and molecular changes that occur in salivary glands during diabetes.


METHODS
Biopsy samples of parotid glands were excised from non-diabetic and diabetic (type 1 and type 2) consenting patients and processed by standard methods for routine morphology and electron microscopic immunogold labeling. Specific antibodies were used to determine and quantify the expression of secretory proteins (alphaamylase and the regulatory subunit of type II protein kinase A).


RESULTS
Morphologic changes in the diabetic samples included increased numbers of secretory granules, and alterations in internal granule structure. Quantitative analysis of immunogold labeling showed that labeling densities were variable among the parotid gland samples. In type 1 diabetes amylase expression was greater than in non-diabetic glands, whereas in type 2 diabetes it was not significantly changed. Expression of type II regulatory subunits was slightly, although not significantly, increased in acinar secretory granules of type 1 diabetic samples and was unchanged in type 2 diabetic samples.


CONCLUSIONS
Our data show that diabetes elicits specific changes in secretory protein expression in human salivary glands, thus contributing to the altered oral environment and oral disease associated with diabetes.
Piras
Monica
M
Department of Cytomorphology, University of Cagliari, Cittadella Universitaria di Monserrato, Monserrato (CA), Italy. mpiludu@unica.it
Hand
Arthur R
AR
Mednieks
Maija I
MI
Piludu
Marco
M
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D016022:Case-Control Studies; D002373:Cyclic AMP Receptor Protein / Q000096:biosynthesis*; D003922:Diabetes Mellitus, Type 1 / Q000378:metabolism* / Q000473:pathology; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010306:Parotid Gland / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D022142:Secretory Vesicles / Q000473:pathology; D000516:alpha-Amylases / Q000096:biosynthesis*
D002373:Cyclic AMP Receptor Protein; D000516:alpha-Amylases