Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0086543 (cataract)
 29,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We examined biochemically the lysosomal enzyme activities in tear fluids from patients with mild myopia, senile cataract, and Terrien's marginal corneal degeneration. Tear acid phosphatase activities in Terrien's degeneration were almost the same as those in mild myopia and senile cataract, while those of N-acetyl-beta-D-glucosaminidase in Terrien's degeneration were higher. The high activity of tear N-acetyl-beta-D-glucosaminidase may be derived from the lacrimal gland and infiltrate histiocytelike cells in Terrien's marginal corneal degeneration.
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PMID:Lysosomal enzymes in tear fluids from patients with Terrien's marginal corneal degeneration. 366 76

Previous cytochemical and biochemical studies have shown an increase in the activity of acid phosphatase and arylsulfatase during the induction of galactose cataracts in rat lenses. It was postulated that these enzymes may be involved in lens fiber degradation observed during cataractogenesis, however, the role of these enzymes in the repair process was not ruled out. The present investigation has evaluated the level of acid phosphatase activity in lenses in which the induction of opacity is inhibited with the aldose reductase inhibitor sorbinil and during the recovery of galactose induced opacity. Sprague-Dawley rats received 50% galactose diet, or galactose diet with sorbinil, or laboratory chow diet. Following 20 days on this diet all rats received lab chow plus 50 mg kg-1 sorbinil (recovery diet). The lenses were removed at desired intervals following the initiation of the above three diets and following the transfer of animals to the recovery diet. Cytochemical localization and biochemical quantitation of acid phosphatase activity were performed with methods previously reported. Most of the enzyme activity was localized within the epithelial cells and superficial cortical fibers. In the epithelial cell layer, the enzyme activity was primarily localized in lysosomes and at extracellular sites near the epithelial cell membrane which abut each other and cortical fibers. In cortical fibers the enzyme activity was observed at various extracellular sites between the cell membranes of neighboring fibers. The effect of sorbinil, if any, and the possible role of acid hydrolases in the repair process during cataract reversal is discussed.
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PMID:Acid phosphatase II. Cytochemical localization in lenses of normal and galactose-fed rats. 392 63

We have demonstrated an increase in activity of arylsulfatase A and B during galactose induced cataract development in rats. Our recent investigation shows that acid phosphatase activity, which increases substantially during galactose cataract development in rats, could be contained to near normal level if Sorbinil, an aldose reductase inhibitor, was fed along with galactose to the rat. We have observed that the activity of other lysosomal enzymes, arylsulfatase A and/or B, also increases during galactose cataractogenesis. In the present report, we provide information with regards to the effect of Sorbinil on the activity of these enzymes during cataractogenesis. A modified Hopsu-Havu and Helminen method (1974) with p-nitrocatecholsulfate as substrate was used for localization of both arylsulfatase A and B; and the method of Hara et al. (1979) was utilized to obtain quantitative data on the level of arylsulfatase A and B activity. Ultrastructural cytochemistry shows that arylsulfatase activity in all lenses was primarily localized in epithelial cells in lysosomes with very little or no activity in cortical fibers. The number of arylsulfatase positive lysosomes and the activity level of these enzymes increased with the progression of cataract development. Galactose induced damage to lens morphology and increase in activity of arylsulfatase A and B was inhibited by inclusion of 50mg/Kg (diet) Sorbinil in the galactose containing cataractogenic diet. However, Sorbinil had no significant effect on the enzyme activity following the establishment of mature cataracts.
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PMID:Ultrastructural cytochemistry: effect of Sorbinil on arylsulfatases in cataractous lenses. 402 88

Localization of acid phosphatase activity is described in equatorial segments of four human cataractous lenses, including one lens with equatorial cortical cataract, and three lenses with no significant equatorial opacities. The lenses were removed surgically with a cryoprobe. Enzyme reaction product was confined mostly to epithelial and cortical Golgi complexes and dense bodies, and to cortical smooth endoplasmic reticulum (SER). It also was located in small cortical vacuolar cysts in the lens with equatorial cataract, and intercellularly in a single lens which was devoid of equatorial opacity. In the latter case, intercellular activity was confined mostly to areas showing minimal pathological modification. Evidence is presented that the cortical SER represented GERL. The hypothesis is made that intercellular acid hydrolase activity might play a role in the early stages of human senile cortical cataract development. However, it is recognized that confirmation of this hypothesis will require additional studies involving comparison of both cataractous and normal lenses of various ages, which have been removed by a careful procedure which minimizes the lysis of lens cells.
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PMID:Acid phosphatase localization in the equatorial region of human lenses. 648 64

Lenses from normal Wistar rats and those from a Wistar strain with X-ray-induced cataract mutation were examined electron microscopically for morphological characterization and acid phosphatase (AcPase) localization. Ocular anlages of 11 through 18 days of gestation were included in the study. A late-separating or persistent lens stalk occasionally was seen in the mutant eyes at 13 days of gestation, but never was observed in eyes of normal animals. The first regular morphological lens abnormality, also observed at 13 days, consisted of an accumulation of unelongated fiber cells (fusiform cells) in the posterior of the mutant lens. Ultrastructurally, these cells contained increased amounts of polyribosomes and coagulated proteins, but lacked the microtubules characteristic of elongated fiber cells. Intercellular AcPase activity appeared in the lens epithelium of both strains of rat beginning at 13 days of gestation, but was sparse in the normal strain. Intercellular reaction product attributable to AcPase activity also was noted in persistent lens stalks. In all ages combined, 66% of the mutant lenses, but only 20% of the normal lenses displayed intercellular activity. The Golgi/GERL complex in the apical regions of the lens epithelial cells of both strains contained AcPase reaction product. Reactive coated vesicles assumed to be primary lysosomes were present in nearby cytoplasm or associated with the Golgi/GERL. It is possible that the elevated amounts of hydrolase activity found in the mutant lenses may play a role in the development of the cataract characteristic of this lens.
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PMID:Ultrastructural and acid phosphatase histochemical analysis of developmental lens abnormalities in rats with X-ray-induced cataract mutation. 671 60

Lenses of cataract-webbed (cw) Peromyscus maniculatus were examined by electron microscopy and compared to age-matched normal deer mouse lenses. Precataractous lenses of offspring of cw/cw matings were examined and compared to early cataract development in the opposite eye of the same animal. The earliest ultrastructural change leading to disturbance of lens transparency was cell fusion and formation of fiber cell syncytia in the posterior subcapsular region. Fiber cells lost their regular hexagonal packing. Small osmiophilic densities on the plasma membrane coincided with many of the sites of cell confluency. Larger osmiophilic whorls were usually localized in ball-and-socket interlocking junctions after the opacity spread. Epithelial cells from the nasal ventral equator migrated to the posterior pole. Later when underlying cortical fibers ruptured, the migrated cells phagocytized lens proteins and incorporated them in acid-phosphatase positive lysosomes. Fiber cells 3 to 20 layers deep in the cortex of normal and cataractous lenses had acid phosphatase reaction product coating the plasma membrane; the possible significance of this finding is discussed. We postulate that this hereditary cataract results from a defect in turnover and control of plasma membrane components.
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PMID:Ultrastructure and acid phosphatase activity in hereditary cataracts of deer mice. 739 Jul 24

The anterior lens epithelial cells undergo a variety of degenerative and proliferative changes during cataract formation. Acid phosphatase is primarily responsible for tissue regeneration and tissue repair. The lipid hydroperoxides that are obtained by lipid peroxidation of polysaturated or unsaturated fatty acids bring about deterioration of biological membranes at cellular and tissue levels. Acid phosphatase and lipid peroxidation activities were studied on the lens epithelial cells of nuclear cataract, posterior subcapsular cataract, mature cataract, and mixed cataract. Of these, mature cataractous lens epithelium showed maximum activity for acid phosphatase (516.83 moles of p-nitrophenol released/g lens epithelium) and maximum levels of lipid peroxidation (86.29 O.D./min/g lens epithelium). In contrast, mixed cataractous lens epithelium showed minimum activity of acid phosphatase (222.61 moles of p-nitrophenol released/g lens epithelium) and minimum levels of lipid peroxidation (54.23 O.D./min/g lens epithelium). From our study, we correlated the maximum activity of acid phosphatase in mature cataractous lens epithelium with the increased areas of superimposed cells associated with the formation of mature cataract. Likewise, the maximum levels of lipid peroxidation in mature cataractous lens epithelium was correlated with increased permeability of the plasma membrane. Conversely, the minimum levels of lipid peroxidation in mixed cataractous lens epithelium makes us presume that factors other than lipid peroxidation may also account for the formation of mixed type of cataract.
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PMID:Acid phosphatase and lipid peroxidation in human cataractous lens epithelium. 800 48

In this work an attempt has been made to analyze the relationship between genetic markers and the occurrence of congenital cataract in children. The study included 32 families with 66 children in whom various clinical forms of congenital cataract had been diagnosed. In all examined patients, genetic markers such as ABO, MN, Rh systems, Gm1 factor, acid phosphatase (ACP1), esterase D and haptoglobin group were determined. The results were compared with the control population. It was found that the frequency of occurrence of heterozygote phenotype Hp 2-1 is higher in families with congenital cataract with simultaneous decrease of the frequency of occurrence of homozygote Hp 2-2. The obtained data were compared with those of other authors.
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PMID:[Genetic markers and congenital cataract]. 807 67

The aim of this study was to examine the chronic effects and mode of action of doxorubicin in ocular tissues. A dose of 10 microg (17.24 nanomoles) of doxorubicin hydrochloride in 20 microl sterile saline were intravitreally injected, under local anaesthesia, in one eye of 13 rabbits and 50 microg (86.20 nanomoles) were similarly injected in one eye of 3 rabbits. The contralateral eye received 20 microl of saline only. The dose of 50 microg induced initially mild uveal inflammation which became chronic and turned into circular iritis. Both doses of the drug induced cataract of the lens and clouding of the cornea within 2-3 months. The activity of superoxide dismutase, in iris-ciliary bodies and lenses treated with either 10 or 50 microg of the compound, was significantly lower relative to that in respective control tissues. In contrast to superoxide dismutase, catalase showed an increased activity in experimental tissues relative to control. The lysosomal hydrolases acid phosphatase, N-acetyl-B-D-glucosaminidase, aryl sulphatase and acid cathepsin, all showed significantly elevated activities in iris-ciliary body tissues one year after injection with the 50 microg doxorubicin. The reduction in superoxide dismutase activity may render ocular tissues susceptible to peroxidative attack and the increased activities of lysosomal hydrolases may contribute to chronic cell injury and inflammation.
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PMID:Biochemical changes induced by intravitreally-injected doxorubicin in the iris-ciliary body and lens of the rabbit eye. 1043 98