Beta-glycosidases and diabetic microangiopathy. I. Decreases of beta-glycosidase activities in diabetic rat kidney.

Deposition of PAS2-positive materials and thickening of the basement membrane in vascular lesions are characteristic findings in diabetes mellitus, suggesting altered metabolism of glycoprotein. Changes in the activities of the glycosidases, beta-N-acetylglucosaminidase [EC 3.2.1.30], beta-glucuronidase [EC 3.2.1.31], beta-galactosidase [EC 3.2.1.23], and beta-glucosidase [EC 3.2.1.21] were measured in various organs and the serum of diabetic rats. The activities of the first three enzymes listed above were found to be much reduced in the kidney but increased in the serum. The decreased activities of beta-glycosidases in the kidney may be one of the factors responsible for the pathogenesis of microangiopathy.