Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.20 (alpha-glucosidase)
 4,237 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In developing chick embryos, hydrocortisone induces cataract formation following a decrease in lens glutathione content but an increase in lipid peroxide content in lens, blood and liver. The preventive effects of ascorbic acid 2-O-alpha-glucoside (AA-2G) on these parameters were compared on cataract formation with those of ascorbic acid (AsA) and ascorbic acid 2-O-phosphate (AA-2P). In these tissues, AA-2G inhibited a decrease in glutathione content and an increase in lipid peroxide content more effectively than either AsA or AA-2P. Various tissues including lens and liver have alpha-glucosidase activity, strongly suggesting that AsA is enzymatically liberated from AA-2G in these tissues. In summary, these results suggest that AA-2G exerts a potent anti-cataract activity via a reduction in oxidative damage through AsA release.
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PMID:Effect of ascorbic acid 2-O-alpha-glucoside on hydrocortisone-induced cataract formation in developing chick embryos: II. Influence on glutathione and lipid peroxide contents in the lens. 783 62

This paper describes the glycosidases in normal lenses and the variation in their activities during aging and with the advance of cataract. In normal human lenses, four glycosidases, alpha-L-fucosidase, alpha-D-glucosidase, beta-D-glucuronidase and beta-D-galactosaminidase, exhibited strong specific activities, which fell sharply between the ages of 40 and 60. In the 50-60 age group the enzyme activities fell sharply to one-tenth and below those in the lenses of the 20-30 age group. The Km value of each enzyme also depended on age and exhibited some variability, suggesting that the substrate affinity of enzyme may be changeable. These facts show that the specific activities and Km values of some glycosidases in normal human lenses change with aging. The activities of the four glycosidases in lenses with senile cataract were also determined as a function of advanced cataract stage. The activities of the four enzymes were weak in the lenses of the younger age groups, and were undetectable in the lenses of older groups, over 60-year of age. This shows that cataract formation may have a deleterious effect on the catalytic activity of some glycosidase and inhibit them strongly.
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PMID:Variation in the glycosidase activity of human lens during aging and with advance of senile cataract. 859 55