Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sugar cataract formation has been demonstrated to result from lenticular sorbitol accumulation. In the lens, the activity of aldose reductase has been observed to increase with the onset of diabetes, while the activity of sorbitol dehydrogenase decreases. This shift in activities of these two Sorbitol Pathway enzymes favors the increased accumulation of sorbitol. Immunohistochemical studies with antibodies prepared against purified rat lens aldose reductase reveal a striking increase in immunoreactive positive staining for aldose reductase in lenses from diabetic rats. Two weeks after the onset of diabetes, increased immunohistochemical staining for aldose reductase appears beneath the epithelial region where water cleft formation occurs, and the intensity of this staining increases with the formation of vacuoles. By 6-8 weeks, the presence of large vacuoles and areas of liquifaction containing dense immunoreactive stain can be observed. Examination of human cataractous lenses with antibodies prepared against purified human placenta aldose reductase suggest similar increases in immunoreactive staining in the human diabetic lens. Cataractous lenses from diabetic patients revealed increased immunoreactive staining for aldose reductase, which was associated with the presence of vacuoles in both the anterior or posterior superficial cortical layers. Examination of similar vacuole containing regions from non-diabetic cataractous lenses revealed no increase in immunoreactive staining for aldose reductase. These results suggest that the enhanced activity of aldose reductase observed in diabetes is due to an increased amount of enzyme, rather than enzyme activation.
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PMID:Immunohistochemical localization for aldose reductase in diabetic lenses. 310 Apr 73

Streptozotocin-induced diabetes increased sorbitol levels in the rat renal medulla. The activities of renal medullary aldose reductase and sorbitol dehydrogenase, responsible for the formation and metabolism of sorbitol, favor sorbitol formation and did not change in diabetes. The elevated sorbitol concentration appears to be due to an increase in medullary glucose concentration.
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PMID:Renal sorbitol accumulation and associated enzyme activities in diabetes. 313 95

Sorbitol concentration has been measured in retina, optic, and sural nerve of normal, diabetic, and aldose reductase inhibitor-treated diabetic rats. The sural nerve displayed significantly higher sorbitol content than the retina and the optic nerve both in control animals and in diabetic animals. In the sural nerve the response to treatment with an aldose reductase inhibitor was more marked than in the two other tissues. The activities of aldose reductase and sorbitol dehydrogenase were not influenced by diabetes. It is suggested that aldose reductase inhibition may be of greater use for alleviating peripheral nervous system accumulation of sorbitol than for hindering CNS accumulation of the polyol.
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PMID:Sorbitol metabolism in the retina, optic nerve, and sural nerve of diabetic rats treated with an aldose reductase inhibitor. 314 49

Increase in content of glucose in aorta as well as in reducing properties of NAD and NADP coenzymes and alteration in content of cofactor of the sorbitol pathway led to accumulation of sorbitol in streptozotocin-diabetic rats. Administration of nicotinamide into diabetic animals induced an increase in the ratios of NAD+/NADH and NADP+/NADPH, accompanied by a decrease in sorbitol formation occurring in the reaction catalyzed by aldose reductase and stimulation of the sugar oxidation in the reaction catalyzed by sorbitol dehydrogenase. Possible use of nicotinamide for prevention and treatment of vascular lesions in diabetes is discussed.
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PMID:[Nicotinamide coenzyme regulation of the sorbitol pathway of glucose metabolism in the aorta of rats with streptozotocin diabetes]. 315 51

Quantitative screening for red blood cell sorbitol dehydrogenase (RBC-SORD) deficiency in 111 patients with juvenile onset diabetes, 92 patients with adult onset diabetes, 42 patients with idiopathic cataracts and 192 professional blood donors was performed. A wide variability in RBC-SORD activity in controls and patients was observed. No significant differences in SORD activity either between patients with diabetes and patients with idiopathic cataracts or between diabetics with and without cataracts were observed. Whether or not there were carriers for either amorphous or hypomorphous alleles of the SORD locus in the population studied could not be defined in terms of enzymatic activity levels.
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PMID:Screening for red blood cell sorbitol dehydrogenase deficiency in patients with diabetes or cataracts. 343 60

Polyhydric alcohols (polyols) are widely distributed in nature, and the enzymes of the polyol pathway (aldose reductase and sorbitol dehydrogenase) are present in many mammalian tissues. The function of this pathway remains a mystery. A primary role for the pathway in the pathogenesis of 'sugar cataract' was provided by a number of experimental observations and in the 1960s the 'osmotic hypothesis' was propounded. This hypothesis also had implications for the pathogenesis of diabetic neuropathy. However, in the 1970s doubts were raised about the validity of the hypothesis, culminating in experiments which suggested that abnormalities in myo-inositol metabolism in nerve and lens were more closely related to the glucose-induced functional changes in these tissues than was the polyol pathway. Nevertheless, increased activity of the polyol pathway must still be regarded as an instigator of the biochemical abnormalities that lead to damage of lens and nerve in diabetes mellitus.
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PMID:The polyol pathway. A historical review. 379 30

Screening for red blood cell sorbitol dehydrogenase deficiency in 12 different mammalian species was performed. A wide inter-species variability in red cell sorbitol dehydrogenase with a virtually complete deficiency in pigs was observed. Aldose reductase and sorbitol dehydrogenase activities in 12 different pig tissues also were measured. Aldose reductase activity was present in all the tissues studied, whereas organ specificity for sorbitol dehydrogenase was observed. Sorbitol dehydrogenase activity was not detectable in lenses, among other tissues, making the pig a potential model for studies in experimental diabetes, particularly for the investigation of sorbitol dehydrogenase deficiency as a risk factor in the development of cataracts.
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PMID:Sorbitol dehydrogenase deficiency in several pig tissues: potential implications for studies of experimental diabetes. 643 86

The content of lactate in mixed saliva in severe diabetes mellitus associated with multiple caries was 5 times and in diabetes of medium severity 3.5 times greater than in caries-resistant subjects. This increase was largely caused by diabetes proper, since in multiple caries without diabetes, the lactate content was increased only 2-fold. The amount of pyruvate in saliva in multiple caries without diabetes was approximately the same as that in diabetes mellitus coupled with multiple caries. Preliminary administration to the oral cavity of 100 ml of 50% saccharose for 10 minutes (without swallowing) raised the saliva lactate content several times as compared to that in the same subjects before saccharose administration. The lactate content in saliva was particularly high in severe diabetes mellitus. Administration of 50% sorbitol of the oral cavity for 10 minutes did not increase the lactate content in saliva. Upon administration of saccharose lactate dehydrogenase activity in saliva significantly descended while sorbitol dehydrogenase activity significantly increased. Administration of sorbitol solution to the oral cavity did not produce any essential effect on sorbitol dehydrogenase activity in saliva.
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PMID:[Effect of saccharose and sorbit on indices of carbohydrate metabolism in mixed saliva of patients with diabetes mellitus and dental caries]. 663 40

A new fluorimetric method for the quantification of red blood cell (RBC) sorbitol dehydrogenase is described. It is based on the oxidation of sorbitol to fructose, in presence of NAD+, catalysed by the RBC-sorbitol dehydrogenase. The quantity of NADH formed is then measured in a filter fluorimeter. Comparison with an indirect spectrophotometric assay yielded good correlation; however, the present method offers several advantages: it is more rapid, simple and inexpensive. It should be useful to screen for sorbitol dehydrogenase deficiency in large numbers of individuals, particularly patients with diabetes or cataracts.
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PMID:A fluorimetric method for red blood cell sorbitol dehydrogenase activity. 685 34

The administration of the dried leaf powder of Gymnema sylvestre regulates the blood sugar levels in alloxan diabetic rabbits. G. sylvestre therapy not only produced blood glucose homeostasis but also increased the activities of the enzymes affording the utilisation of glucose by insulin dependent pathways: it controlled phosphorylase levels, gluconeogenic enzymes and sorbitol dehydrogenase. The uptake and incorporation of [14C] glucose into the glycogen and protein are increased in the liver, kidney and muscle in G. sylvestre administered diabetic animals when compared to the untreated diabetic animals. Pathological changes initiated in the liver during the hyperglycemic phase are reversed by controlling hyperglycemia by G. sylvestre. G. sylvestre, a herb used for the control of diabetes mellitus in several parts of India, appears to correct the metabolic derangements in diabetic rabbit liver, kidney and muscle.
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PMID:Enzyme changes and glucose utilisation in diabetic rabbits: the effect of Gymnema sylvestre, R.Br. 686 51


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