acid-phosphatase and Diabetic-Retinopathy

Cytosolic low molecular weight acid phosphatase (ACP1) is a high polymorphic phosphotyrosine-protein-phosphatase involved in signal transduction. In NIDDM subjects we have found that ACP1 genotype is a highly significant predictor of retinopathy, suggesting that genetic variability of signal transduction may have an important role in the susceptibility to this complication. Adenosine deaminase, ABO blood groups and several clinical variables have been also considered. The results point out the importance of interactions between genetic systems. Among non-genetic variables dislipidemia and treatment with insulin are significantly associated with retinopathy.

Topics: Acid Phosphatase; Adenosine Deaminase; Adult; Aged; Aged, 80 and over; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Female; Humans; Male; Middle Aged; Regression Analysis; Signal Transduction

Using a new method to collect vitreous fluid safely during vitrectomy, vitreous specimens were obtained from 18 eyes of diabetic patients with proliferative diabetic retinopathy (PDR) and from 14 eyes of nondiabetic patients. The activities of four lysosomal acid hydrolases in these samples were measured and compared with those in serum. Of these enzymes, only N-acetyl-beta-glucosaminidase (NAG), a suspected retinal angiogenic factor, showed higher activity in the vitreous than in the serum in both diabetic (P less than 0.005) and nondiabetic eyes (P less than 0.05). However, no significant difference was found in any enzyme activity between diabetic and nondiabetic samples. These results suggested that this enzyme apparently does not have a significant effect, at least on the pathologic condition, during the late stage of PDR, and that NAG is usually present at higher activity in the vitreous than in the serum of diabetic as well as nondiabetic patients.

Topics: Acetylglucosaminidase; Acid Phosphatase; Adolescent; Adult; Aged; alpha-L-Fucosidase; Child; Diabetic Retinopathy; Humans; Lysosomes; Middle Aged; Specimen Handling; Vitrectomy; Vitreous Body

Cytochemical studies have been performed on peripheral blood lymphocytes of 68 diabetic subjects, with various conditions of metabolic control, and 15 newly diagnosed insulin-dependent diabetic patients. 20 patients of the 1 group had diabetic retinopathy. In diabetic patients periodic acid Schiff positivity, acid phosphatase, and N-acetyl-beta-glucosaminidase activities of lymphocytes are fairly impaired, particularly in insulin-dependent diabetes. Concerning the alpha-naphthyl-acetate-esterase activity, the percentage of positive cells with coarse granules is significantly reduced (p less than 0.001) in diabetic patients as compared to controls, without difference related to age and sex. These abnormalities are more evident in patients with poor glyco-metabolic control. In patients with newly diagnosed insulin-dependent diabetes we have found a further decrease in alpha-naphthyl-acetate-esterase activity, and an increase in acid phosphatase and N-acetyl-beta-glucosaminidase activities. Cyto-enzymatic activities are not significantly different in subjects with diabetic retinopathy. The results of peripheral lymphocyte enzymatic activities in diabetics could be related to a depression of the cell-mediated immunity and could enhance the infections risk of these patients. Furthermore our data show an altered immunological balance in subjects with newly diagnosed type I diabetes.

Topics: Acid Phosphatase; Adult; Aged; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Female; Hexosaminidases; Histocytochemistry; Humans; Lymphocytes; Male; Middle Aged; Naphthol AS D Esterase; Periodic Acid-Schiff Reaction

Four Wistar inbred rats made diabetic by an injection of streptozotocin and four control rats were killed after an experimental period of 12 months. Eye tissues were prepared for examination and detection of acid phosphatase (AcPase) by electron microscopy. In the retina of control animals, the Müller cell cytoplasm had a small number of highly electron-dense bodies. AcPase reaction products were seen on these dense bodies and on Golgi lamellae of Müller cells. In the diabetic rat retina, a greater number of these lysosome-like bodies were seen, especially in cell processes adjacent to capillaries and in those at the vitreoretinal interface. Increased deposits of AcPase reaction products were detected on Golgi lamellae, smooth endoplasmic reticulum, and highly electron-dense bodies. The functional significance of a marked increase in lysosomal enzymes within Müller cells is uncertain. The phenomenon may occur in order to eliminate cellular debris derived from necrotic pericytes and to digest excessive glycogen accumulated in the retina under diabetic conditions.

Topics: Acid Phosphatase; Animals; Diabetes Mellitus, Experimental; Diabetic Retinopathy; Golgi Apparatus; Lysosomes; Male; Microscopy, Electron; Rats; Retina

Topics: Acid Phosphatase; Diabetic Retinopathy; Diathermy; Humans; Hyaluronoglucosaminidase; Hyperthermia, Induced; Surgical Procedures, Operative

Topics: Acid Phosphatase; Adrenal Cortex Hormones; Chymotrypsin; Diabetic Nephropathies; Diabetic Retinopathy; Humans; Hyaluronoglucosaminidase; Hypoglycemic Agents

Topics: Acid Phosphatase; Adrenal Cortex Hormones; Diabetic Retinopathy; Humans; Hyaluronoglucosaminidase