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)

The aim of this study was to estimate the anticataract action of vitamin E using an in vitro methylprednisolone (MP)-induced cataract model. The same severity of early cortical cataract was induced in lenses isolated from male Wistar rats aged 6 weeks by incubation with MP (1.5 mg/ml) in TC-199 medium. The cataractous lenses showed slight increases in lipid peroxide (LPO) content and Na+/K+ ratio and slight decreases in reduced glutathione (GSH) content and glyceraldehyde-3-phosphate dehydrogenase (GAP-DH), a sensitive index of oxidative stress, and Na+,K(+)-ATPase activities. When the cataractous lenses were further incubated in TC-199 medium with and without vitamin E (250 micrograms/ml) for 48 h, the progression of cataract was prevented in the vitamin E-treated lenses, but not in the vitamin E-untreated lenses. The vitamin E-untreated lenses showed a decrease in vitamin E content and an increase in water content in addition to further increases in LPO content and Na+/K+ ratio and further decreases in GSH content and GAP-DH and Na+,K(+)-ATPase activities. In contrast, the changes of these components and enzymes except for GSH were attenuated in the vitamin E-treated lenses. From these results, it can be estimated that vitamin E prevents in vitro cataractogenesis in rat lenses treated with MP by protecting the lenses against oxidative damage and loss of membrane function.
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PMID:Anticataract action of vitamin E: its estimation using an in vitro steroid cataract model. 888 85

Biochemical evidence on lens culture suggests that antioxidant nutrients can protect lens against peroxidation caused by radiation. A case-control study was carried out on 262 middle aged (45-54) and aged (55-64) subjects. The relationship between biochemical markers of antioxidant status and senile lens changes (including cataract) was examined in 131 subjects with senile lens changes and 131 control subjects with clear lens. Antioxidant status was measured using plasma and erythrocyte glutathione peroxidase, erythrocyte superoxide dismutase and catalase activity and plasma levels of vitamin E and vitamin A. Subjects were grouped by age and sex. The results were as follows: (1) The subjects with lens changes tended to have lower plasma levels of vitamin E and vitamin A, lower activity of several antioxidant enzymes and higher level of MDA. (2) The subjects with senile lens changes had significantly lower erythrocyte glutathione peroxidase level. (3) In the middle-aged group, subjects with senile lens changes were observed to have lower erythrocyte and plasma glutathione peroxidase level than those without senile lens changes. The results suggest that appropriate amount of antioxidant nutrients might be expected to prevent or retard the process of lens changes.
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PMID:Antioxidant status in persons with and without senile lens changes. 888 25

Experimental work from our laboratory has confirmed the protective power of vanadium compounds on hyperglycemia and glycosuria in streptozotocin (STZ) diabetes. Furthermore, the diabetic cataract too has been partially prevented. The protection slightly increased, when vanadium was administered in combination with vitamin E. This investigation has introduced a combination of Na3VO4 plus the lazaroid U-83836E, a liposoluble antioxidant much more efficacious than tocopherol, in order to improve the insufficient protection when vitamin E was used. Male Wistar rats, rendered diabetic with STZ, were treated for 12 weeks with Na3VO4 in drinking water, U-83836E carried by the food, or both. The most significant metabolic parameters (food and fluid intake, diuresis and excreted feces) were studied monthly by means of metabolic cages. Body weight, glycemia, glycosuria and proteinuria were also recorded. At week 6 and 12 of the treatment, the opaqueness of the eye lenses was controlled. Circulation glycosylated hemoglobin (HbA1c), fructosamine, N-acetyl-beta-D-glucosaminidase (NAG) and fluorescent peroxides were evaluated at the end of the experiment. After the first month of treatment U-83836E improved significantly the protective effect of vanadate alone on polydipsia and polyuria, but more efficiently on hyperglycemia and glycosuria. The further ameliorating effect of the lazaroid was observed also on HbA1c, NAG and, most important, on the cataract. In conclusion, these findings demonstrate that the lazaroid U-83836E succeeds in further protecting the most important symptoms of diabetes treated with vanadate, and that this antioxidant acts effectively even when it is administered per os, in a non invasive manner.
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PMID:[Protective effect on nephropathy and on cataract in the streptozotocin-diabetic rat of the vanadium-lazaroid combination]. 899 28

The indole-3-carboxylic acid scopoine ester. SDZ ICT 322, is a selective hydroxytryptamine (5-HT3) antagonist, which after chronic treatment causes posterior subcapsular cataracts and skin changes such as hair loss, hyperaemia, desquamation and hyperkeratosis in rats. The detailed mechanisms underlying these changes are not yet known. In order to evaluate a possible oxidative stress-induced pathomechanism of SDZ ICT 322, the antioxidative defence capacity in rats was modulated by feeding a special vitamin E- and selenium-deficient (VE/SeD) diet. For this purpose 32 male Wistar rats, age 4 weeks, were pretreated for 8 weeks with either a VE/SeD diet or a normal standard diet. Each dietary group was divided into 8 control and 8 SDZ ICT 322-treated animals. SDZ ICT 322 was administered in feed to rats at an adjusted daily dose level of 125 mg/kg for 14 weeks. Plasma levels of SDZ ICT 322 as well as of the N-desmethyl metabolite were similar in rats fed the different diets in weeks 3, 6 and 14. In SDZ ICT 322 treated VE/SeD rats cataracts were observed by week 7, whereas in rats fed normal diet cataracts were first seen in week 14. In the normal dietary group no corneal opacity was found after SDZ ICT 322-treatment; however, a corneal opacity was seen in the deficiency group in parallel with one of the cataract animals in week 7. The incidence and severity of clinical skin signs were greater and their onset was earlier in the deficiency dietary group: onset occurred after 6 weeks compared to 9 weeks on the normal diet. Thiobarbituric acid reactive substances, an indicator mainly of oxidized lipids, were statistically significantly increased in the urine of rats administered SDZ ICT 322 and the VE/SeD diet. Uric acid, which is an endogenous antioxidant was statistically significantly decreased in the urine and plasma of SDZ ICT 322 VE/SeD treated rats. The clinical eye and skin changes occurring early after VE/SeD feeding, the unchanged drug plasma exposure and unchanged drug metabolite formation in combination with the general pro-oxidative activity of the drug suggest an oxidative stress-mediated pathomechanism of SDZ ICT 322 at high dose levels in rats.
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PMID:Enhancement of SDZ ICT 322-induced cataracts and skin changes in rats following vitamin E- and selenium-deficient diet. 913 6

Chronic deficiency of various vitamins can influence the occurrence of some chronic degenerative diseases such as cancer, cardiovascular pathology, cataract, arthritis, disorders of the nervous system and photosensitivity. Similarly, vitamin intake can influence various disorders in infants and elderly people, in burns and in subjects following unbalanced diets or undergoing strenuous physical exercise. Among vitamins, beta-carotene, vitamin E and vitamin C have received most attention, particularly in the prevention of oxidative damage from free radicals. It is supposed that each vitamin plays a different role in the pathogenesis of various diseases, depending on the type of damage relevant to a specific disease. Results from different studies are still far from conclusive and the effects on longevity are not well defined. In industrialized countries, vitamin deficiencies seem to be related only to specific and clearly identifiable groups in the population: therefore, at the moment, it seems more advisable to target vitamin supplementation at risk groups.
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PMID:High-risk subjects for vitamin deficiency. 916 37

Anti-cataract activity of vitamin E analog with shortened side chain--2'-4'-methyl-pentenyl-acetoxy-2,5,7-tetramethylchroman has been studied. It is shown on the model system that the analog of vitamin E inhibits the increase of the lens agent fluorescence under irradiation of its homogenates by polychrome light. Taking no negative effect on the lens capsule epithelium, the drug normalizes the content of vitamin E in the blood and increases activity of Na+, K+, ATPase in the cortex and capsule of rabbits lenses in dynamics under simulation of light cataract in vivo.
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PMID:[Anti-cataract activity of a vitamin E analog]. 922 55

Diabetes mellitus in pregnancy causes congenital malformations in the offspring. The aim of this work was to characterize biochemical and morphologic anomalies in the conceptus of an animal model of diabetic pregnancy. In addition, a preventive treatment against diabetes-induced dysmorphogenesis was developed. Congenital cataract was often found in the offspring of diabetic rats. The fetal lenses had increased water accumulation, sorbitol concentration and aldose reductase activity compared to control lenses. The results suggest that the cataracts form via osmotic attraction of water due to sorbitol accumulation in the fetal lens. Another set of malformations, with possible neural crest cell origin, occurred frequently in offspring of diabetic rats. These included low set ears, micrognathia, hypoplasia of the thymus, thyroid and parathyroid glands, as well as anomalies of the heart and great vessels. Furthermore, diabetes caused intrauterine death and resorptions more frequently in the late part of gestation. When the pregnant diabetic rats were treated with the antioxidants butylated hydroxytoluene, vitamin E or vitamin C, the occurrence of gross malformations was reduced from approximately 25% to less than 8%, and late resorptions from 17% to 7%. This suggests that an abnormal handling of reactive oxygen species (ROS) is involved in diabetes-induced dysmorphogenesis in vivo. Indeed, an increased concentration of lipid peroxides, indicating damage caused by ROS, was found in fetuses of diabetes rats. In addition, embryos of diabetic rats had low concentrations of the antioxidant vitamin E compared to control embryos. These biochemical alterations were normalized by vitamin E treatment of the pregnant diabetic rats. The antioxidants are likely to have prevented ROS injury in the embryos of the diabetic rats, in particular in the neural crest cells, thereby normalizing embryonic development. These results provide a rationale for developing new anti-teratogenic treatments for pregnant women with diabetes mellitus.
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PMID:Congenital malformations in experimental diabetic pregnancy: aetiology and antioxidative treatment. Minireview based on a doctoral thesis. 939 31

The preventive action of vitamin E (Vit. E)-containing liposomes on cataractogenesis was examined in male Wistar rats (five weeks old) fed a 25% galactose diet. Vit. E-containing liposomes prepared with dipalmitoylphosphatidylcholine were instilled into both eyes three times a day over a 45-day period. Cataract appeared at 18-day galactose feeding and developed gradually thereafter. Simultaneous Vit. E-containing liposome instillation delayed this cataractogenesis. Lenses of 18-day galactose-fed rats showed decreases in Vit. E and reduced glutathione (GSH) contents and Na+, K(+)-ATPase activity and increases in lipid peroxide (LPO), galactitol, and water contents. Lenses of 45-day galactose fed rats showed decreases in GSH content and Na+,K(+)-ATPase activity and increases in Vit. E, LPO, galactitol, and water contents. Serum Vit. E and cholesterol levels decreased in 18-day galactose-fed rats, while both levels increased in 45-day galactose-fed rats. Simultaneous Vit. E-containing liposome instillation prevented these changes except for the changes of lenticular galactitol and water contents and serum Vit. E and cholesterol levels. These results indicate that simultaneously instilled Vit. E-containing liposomes can delay cataractogenesis in young adult rats fed a 25% galactose diet mainly by the antioxidative action of Vit. E contained in the instilled liposomes.
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PMID:Preventive action of vitamin E-containing liposomes on cataractogenesis in young adult rats fed a 25% galactose diet. 943 57

Cataractous lenses have been found to have an altered distribution of the intracellular ionic environment: the concentrations of potassium and magnesium being decreased and the concentrations of sodium and calcium increased. These changes arise as a result of changes to lens membrane characteristics causing an increase in lens membrane permeability. In this study flame atomic absorption spectroscopy (AAS) was used for calcium, magnesium, iron and zinc determination, and flame atomic emission spectroscopy (AES) was used for sodium and potassium contents in normal and cigarette smoke-exposed rat lenses. The methods are sensitive enough to detect quantitatively all six cations in a single rat lenses. In this work, six elements, including Ca2+, K+, Na+, Zn2+, Fe2+ and Mg2+ in experimental rat eye lenses and normal transparent lenses were determined. It was found that the concentrations of Ca2+, Na+, Zn2+, and Fe2+ were increased dramatically while K+ and Mg2+ decreased in smoke-exposed rat lenses when compared to the control rat lenses. There were no significant changes between 'smoked' rats supplied with vitamin C and control groups. A positive correlation was found also in the other two groups of 'cigarette smoked' animals supplemented with selenium plus vitamin E and selenium when compared with 'cigarette smoked' without any supplements. These data provide support for the hypothesis that cigarette smoking increases the risk of cataract formation. We investigated whether vitamin C is the most important antioxidant in the body. The roles of diet with optimum amounts of antioxidant vitamins C and vitamin E and the antioxidant mineral selenium are discussed.
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PMID:Protective effects of selenium, vitamin C and vitamin E against oxidative stress of cigarette smoke in rats. 1019 3

The relation of antioxidant nutrients to the incidence of nuclear cataracts was investigated in a cohort of adults aged 43-84 years in the Beaver Dam Eye Study (Beaver Dam, Wisconsin). Nuclear opacity was assessed on a five-point ordinal scale using lens photographs taken at baseline (1988-1990) and at follow-up (1993-1995). Of the 1,354 persons eligible, 246 developed a nuclear cataract (level 4 or 5 opacity) in at least one eye. Antioxidant intakes were assessed using a food frequency questionnaire administered at baseline for time points corresponding to intake during the year preceding baseline and 10 years before baseline (the distant past). Lutein-zeaxanthin was the only carotenoid, out of five examined, that was associated with nuclear cataracts. Persons in the highest quintile of lutein intake in the distant past were half as likely to have an incident cataract as persons in the lowest quintile of intake (95% confidence interval 0.3-0.8). In the overall group, nuclear cataracts were not significantly related to intake of vitamin C or vitamin E. However, vitamins C and E were inversely associated with opacities in persons who had some other risk factors for cataracts. While results of this short term follow-up study are consistent with a possible protective influence of lutein and vitamins E and C on the development of nuclear cataracts, the evidence in the present study provides weak support for these associations.
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PMID:Antioxidant intake and risk of incident age-related nuclear cataracts in the Beaver Dam Eye Study. 1022 16


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