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)

1. Cataract formation in streptozotocin-induced diabetes in rats was reduced by approximately 85% when a diet rich in maize oil (300 g/kg diet) (fat diet) was given, thus confirming results of earlier studies. However, the concentration of sorbitol in the lens of diabetic animals remained high, the values for diabetic rats given the standard diet and the fat died being 65 and 40 mumol/g protein respectively. 2. With the standard diet, the fatty acid profile of the triglycerides of the epididymal fat pads was characterized by a greater relative proportion of saturated fatty acids for the diabetic animals compared to that for the normal animals. The fat diet moderated the tendency towards saturation in the diabetic animals. 3. The fat diet had other effects on the diabetic animals; these included a reduced mortality rate, increased body-weight, a decrease in the daily water intake, and in the daily urinary excretion of glucose and urea. 4. In the diabetic animals the fat diet had no effect on the specific activities in the liver of hexokinase (EC 2.7.1.1), glucokinase (EC 2.7.1.2), phosphofructokinase (EC 2.7.1.11) and pyruvate kinase (EC 2.7.1.40). However, the specific activity of glucose-6-phosphatase (EC 3.1.3.9) was reduced, while that of malate dehydrogenase (decarboxylating) (NADP) (EC 1.1.1.40) was increased. The NAD+:NADH ratio, as calculated from liver pyruvate and lactate concentrations, tended to increase. 5. The results suggested that the fat diet moderated the long-term metabolic effects of diabetes.
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PMID:The effect of an unsaturated-fat diet on cataract formation in streptozotocin-induced diabetic rats. 13 11

We have studied the effect of a crowded (macromolecular) solution on reaction rates of the decarboxylating enzymes urease, pyruvate decarboxylase and glutamate decarboxylase. A variety of crowding agents were used including haemoglobin, lysozyme, various dextrans and polyethylene glycol. Enzyme reaction rates of all three enzymes show two different types of effect that separate the globular proteins from the polysaccharides/polymers. Increasing concentration of globular proteins caused a dramatic rise in enzyme activity up to 30% crowding concentration then the activity decreased, whereas the polymers caused a concentration dependent decrease in activity. The viscosities of the globular proteins were low compared to the polymers. The increased activity with proteins may be due to the decreased amount of free water, which leads to higher effective concentration of substrates, or to an increased oligomeric state by self-association. The lower activities of all enzymes with all agents at high concentrations may be explained by a decrease in rates of diffusion. An increase in protein crowding (decrease in cell water content) may contribute to pathological conditions including cataract and Alzheimer's disease.
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PMID:The effect of the presence of globular proteins and elongated polymers on enzyme activity. 1672 Jan 13