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)

There is evidence that ibuprofen and paracetamol can act as anti-cataract drugs. [14C]-Ibuprofen labelled at the methyl group of the propanoic acid moiety was synthesized. The labelled ibuprofen was found to bind non-covalently to alpha-crystallin but not to beta- and gamma-crystallin of the bovine lens. Labelled paracetamol binds to total lens soluble proteins. Both drugs penetrate into the lens cortex and nucleus within 24 hr. Affinity chromatographic studies suggest that the lipophilic isobutyl group of ibuprofen hinders binding to the lens proteins. Hence, in the light of weak binding of ibuprofen and paracetamol and strong binding of the ibuprofen analogue used in the affinity chromatography, it is suggested, in this paper, that the protection against cataract by these analgesics is possibly due to their metabolites interacting with the lens proteins.
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PMID:Investigations of ibuprofen and paracetamol binding to lens proteins to explore their protective role against cataract. 195 25

Cataract is the major cause of blindness worldwide. Non-enzymic modification of lens proteins leading to a disruption of their short range order is an important route to cataract formation. A reaction between lens proteins and a compound found in the lens indicates a potential role for that compound in cataract formation. The reactions of glucose and fructose with lens protein in vitro were investigated. Fructose bound to lens protein at pH 6.9 in a time-dependent fashion over a period of 20 days. The reactions of both glucose and fructose with lens proteins and bovine serum albumin led to the formation of coloured and fluorescent compounds. The formation of such compounds was greater with fructose than with glucose. The kinetics of the reactions of lens proteins and bovine serum albumin with fructose as measured by the formation of the above compounds were not identical. This point must be appreciated when attempting to extrapolate from results obtained with bovine serum albumin as to the reactions of lens proteins. The incubation of lens proteins with fructose led to an enhancement of protein aggregation. The implications of the reactions between lens proteins and fructose for the formation of cataract in diabetics are discussed. Ibuprofen intake is associated with protection against cataract. At relatively high concentrations (10-20 mM) ibuprofen decreased the binding of fructose to lens protein: this decrease was statistically significant at selected times (Student's t-test, P less than 0.05). The formation of fluorescent compounds in the presence of fructose was also decreased by ibuprofen.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Non-enzymic modification of lens proteins by glucose and fructose: effects of ibuprofen. 201 2

Cataract, the major cause of blindness world-wide, may be caused partly by modification of lens proteins by carbamylation and non-enzymic glycosylation (glycation) in some patients. Aspirin has been found to protect against these modifications and to prevent cyanate-induced opacification occurring in whole rate lenses. Ibuprofen is an aspirin-like anti-inflammatory drug which appeared as a protective factor against cataract in an Oxford case-control study. The binding of cyanate, galactose and glucose 6-phosphate to lens proteins, and the effect of ibuprofen on this reaction was investigated, as was cyanate-induced opacification in whole rat lenses. Labelled metabolite was incubated with bovine lens homogenate in the presence and absence of ibuprofen, and the incorporation of label into the lens homogenate was followed. Simultaneous and preincubation experiments were performed. Intact rat lenses were incubated in culture medium with and without cyanate and ibuprofen. The phase separation temperature was noted as the temperature at which opacity first appeared on cooling. Cyanate, galactose and glucose 6-phosphate bind progressively to lens proteins. Simultaneous incubation with ibuprofen reduces cyanate and galactose binding but not glucose 6-phosphate. Ibuprofen protects against opacities due to cyanate-induced phase separation. Ibuprofen has protected against cataract in the models of cataractogenesis in this study. It appears to have a different mechanism of action from that of aspirin. These studies provide some support for the idea, based on epidemiological findings, that ibuprofen might be a useful anti-cataract drug.
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PMID:Ibuprofen, a putative anti-cataract drug, protects the lens against cyanate and galactose. 231 79

Ibuprofen and its major metabolites were incubated with catalase and fumarase, in the presence of protein-modifying biomolecules, to explore the mode of action of ibuprofen in protection against cataract. Both 2 and 10 mM ibuprofen/metabolites protected catalase against fructose-, cyanate- and prednisolone-induced inactivation; the carboxy-metabolite gave the highest protection (31%). The 2 mM ibuprofen/metabolites protected fumarase against fructose- and cyanate-induced inactivation by up to 26%, but had no effect on prednisolone-induced inactivation. Ibuprofen/metabolites did not bind to catalase or fumarase. They penetrated into the lens in vitro. When in the lens, the metabolites may reduce the risk of cataract by protecting lenticular enzymes.
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PMID:Protective effects of ibuprofen and its major metabolites against in vitro inactivation of catalase and fumarase: relevance to cataract. 1200 21

Diclofenac instillation has been used widely in cataract surgery to prevent postoperative inflammation. Since diclofenac binds strongly to albumin in the circulation, it does not have a sufficient effect on patients in whom diclofenac binds strongly to albumin in the aqueous humor. A decrease in diclofenac binding and an increase in free diclofenac levels are necessary in these patients. The binding of diclofenac to albumin was investigated in the aqueous humor. In a diclofenac binding assay with albumin in the aqueous humor of individual patients, diclofenac was extracted from aliquots of the aqueous humor, and its total levels were measured using ultra high performance liquid chromatography (UHPLC). Free diclofenac levels were measured using ultrafiltration and UHPLC. The albumin-binding fraction of diclofenac was 0.8 or higher in the aqueous humor of some patients. Ibuprofen significantly inhibited diclofenac binding to site II of albumin in mimic aqueous humor, but not in pooled aqueous humor. This difference may have been due to the weak binding of diclofenac to site II in the pooled aqueous humor. Flurbiprofen was used instead of diclofenac. Flurbiprofen has been shown to bind more strongly than diclofenac to the same site of albumin. Thus, the inhibitory effect of ibuprofen on the binding of flurbiprofen to albumin was investigated in pooled aqueous humor. The results indicated that ibuprofen significantly inhibited the flurbiprofen binding. An effective diclofenac administration method may be established for clinical application by the instillation of an appropriate inhibitor of binding to the albumin site II.
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PMID:Albumin-binding of diclofenac and the effect of a site II inhibitor in the aqueous humor of cataract patients with the instillation of diclofenac. 2439 76