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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sorbitol is a sugar alcohol formed from the aldose reductase catalyzed reduction of glucose. Mounting experimental evidence links the abnormal intracellular accumulation of sorbitol to the onset and severity of diabetes-associated pathology which results in a variety of tissue and/or functional changes in the cornea, lens, retina, iris, peripheral nerves, and kidney. Animal studies indicate that aldose reductase inhibitors, by inhibiting the formation of sorbitol in target tissues affected by diabetes, can either prevent or significantly delay the onset of many of these diabetes-associated changes. The pioneering studies of Dr Jin Kinoshita have been instrumental in defining the pathophysiological role of aldose reductase and excess sorbitol production under diabetic conditions. These studies provide a firm scientific groundwork for investigating the premise that inhibition of sorbitol formation is a new, pharmacologically direct treatment for diabetic complications that is independent of the control of blood sugar levels.
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PMID:The contributions of Jin H. Kinoshita to aldose reductase research. 211 49

Wide-field specular microscopy was used to examine the central corneal endothelium of age- and sex-matched beagle dogs fed for up to 32 months either normal control diets containing 30% nonnutrient filler (13 dogs) or diets containing 30% galactose with (13 dogs) or without (12 dogs) concomitant treatment with the aldose reductase inhibitor, sorbinil. Computerized morphometric analysis of the endothelial cells indicated that a significant decrease in cell density and increase in mean cell area occurred in untreated galactose-fed dogs after 32 months of feeding compared with the normal controls. However, no significant difference could be observed in similar galactose-fed dogs treated with sorbinil. No significant difference in the coefficient of variation of the area, or percent hexagonality of the endothelial cells, or the corneal thickness could be observed in any group. These findings demonstrated that endothelial abnormalities were present in the cornea of the galactose-fed dogs which were similar to those reported for diabetic dogs, rats, and patients and that these changes can be prevented by the concomitant administration of an aldose reductase inhibitor. These findings suggest a role for aldose reductase in the abnormalities noted in the corneal endothelium in diabetes and galactosemia.
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PMID:The effects of sorbinil, an aldose reductase inhibitor, on the corneal endothelium in galactosemic dogs. 212 61

In view of the increasing awareness of corneal abnormalities in diabetes, five diabetic and five nondiabetic post-mortem corneas were investigated. Indirect fluorescent antibody techniques were used for the detection of immunoglobulin, complement components, fibrinogen, and fibronectin, as some of these had already been found in the kidney, pancreas, and skin of diabetic patients. There was no obvious difference in the deposition of IgG, IgA, IgM, fibrinogen, or fibronectin between diabetic and control corneal specimens. Five diabetic specimens versus three control specimens demonstrated positive staining at 1:50 dilution for complement components Clq, C3, and C4. This staining was primarily present in the epithelium. Of greater interest was the finding that complement components were present in the basement membrane of two diabetic patients, but were not found in nondiabetic patients. In conclusion, diabetic corneas demonstrate unusual staining for complement components in the epithelial basement membrane.
Cornea 1990 Apr
PMID:Immunofluorescent characteristics of the diabetic cornea. 218 64

To test the general applicability of the hypothesis that diabetes mellitus causes increased polyol pathway activity, decreased tissue free myo-inositol, and resultant pathological changes in tissues susceptible to the ravages of diabetes, we measured glucose, sorbitol, and myo-inositol with quantitative histochemical techniques in layers of the cornea, the aortic myointima, the cardiac left ventricle and atrioventricular node (AVN), and retina and kidney after 19 days or 2 mo (mildly diabetic non-insulin-treated [MD] and severely diabetic insulin-treated [SD] groups) in the alloxan-induced diabetes model. In the aqueous humor, glucose rose linearly with increased serum glucose, sorbitol was markedly increased in the MD and SD groups, and myo-inositol did not change in any diabetic group. There was no change in glucose or sorbitol in aortic myointima in any group, but myoinositol was decreased in 19-day diabetic rabbits by 26%, unchanged in MD rabbits but paradoxically increased by 60% in SD rabbits. Glucose, sorbitol, and myo-inositol increased in all three corneal layers in SD rabbits but only in epithelium and stroma in 19-day and MD rabbits. AVN glucose and sorbitol did not change in 19-day diabetic, MD, or SD diabetic rabbits. AVN myo-inositol was three times higher than ventricular myo-inositol and did not appear to change in SD rabbits. Retinal pigmented epithelium myo-inositol was decreased 30% in SD rabbits. Glomerular myo-inositol was also decreased, but not significantly, in SD rabbits. We conclude that the paradoxical increase in corneal and aortal myo-inositol raises fundamental questions about the general applicability of the myo-inositol-depletion hypothesis.
Diabetes 1990 Oct
PMID:Diabetes and the myo-inositol paradox. 221 80

The recovery of the cornea from contact lens-induced edema has been proposed as a clinical test for the assessment of corneal hydration control, with prolonged times being seen in aged subjects and in conditions associated with endothelial dysfunction. Because diabetes is known to be associated with altered endothelial morphology, a study was performed to determine the influence of diabetes on recovery times from contact lens-induced edema. Corneal edema was produced in 10 normal and 10 diabetic rabbits by the monocular wear of a thick hydrogel contact lens on a closed eye for a period of 2 h. Corneal thicknesses measured by ultrasound pachometry at the end of the wearing period showed significantly (p less than 0.0001) more edema in the normal (75 +/- 11 microns) than in the diabetic group (56 +/- 11 microns). Open eye and closed eye recovery times from the induced edema were calculated for both groups using linear and nonlinear regression analysis. The calculated edema recovery rates for the diabetic cornea were significantly slower than those of the normal in both the open eye and closed eye deswelling conditions. The results of this study indicate that the cornea of a diabetic rabbit has a decreased ability to recover from contact lens-induced edema, and suggests that the practitioner should remain aware of the blood glucose levels of his poorly controlled diabetic contact lens patients.
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PMID:Recovery from contact lens-induced edema is prolonged in the diabetic rabbit cornea. 238 90

A case of mitochondrial encephalomyopathy (Kearns-Sayre syndrome) with corneal endothelial abnormality is reported. A 22-year-old woman had retinitis pigmentosa, external ophthalmoplegia, complete heart block, ataxia, muscle weakness, dementia, sensorineural hearing loss, and was of short stature. Renal dysfunction, diabetes mellitus, and amenorrhea were also observed. Biopsy revealed decreased cytochrome c oxidase (complex IV) activity in muscle mitochondria. The corneal endothelium examined by specular microscope showed decreased cell density, severe polymegathism, and pleomorphism in both eyes. To our knowledge, this is the first report concerning primary corneal endothelial abnormality in a case with mitochondrial encephalomyopathy. The corneal endothelium is one of the tissues that could be affected by the enzyme deficiency present in this disease.
Cornea 1989 Sep
PMID:Corneal endothelium in a case of mitochondrial encephalomyopathy (Kearns-Sayre syndrome). 274 82

This discussion reviews drugs that affect the eye, including antihyperglycemic agents; corticosteroids; antirheumatic drugs (quinolines, indomethacin, and allopurinol); psychiatric drugs (phenothiazine, thioridazine, and chlorpromazine); drugs used in cardiology (practolol, amiodarone, and digitalis gylcosides); drugs implicated in optic neuritis and atrophy, drugs with an anticholinergic action; oral contraceptives (OCs); and topical drugs and systemic effects. Refractive changes, either myopic or hypermetropic, can occur as a result of hyperglycemia, and variation in vision is sometimes a presenting symptom in diabetes mellitus. If it causes a change in the refraction, treatment of hyperglycemia almost always produces a temporary hypermetropia. A return to the original refractive state often takes weeks, sometimes months. There is some evidence that patients adequately treated with insulin improve more rapidly than those taking oral medication. Such patients always should be referred for opthalmological evaluation as other factors might be responsible, but it might not be possible to order the appropriate spectacle correction for some time. The most important ocular side effect of the systemic adiministration of corticosteroids is the formation of a posterior subcapsular cataract. Glaucoma also can result from corticosteroids, most often when they are applied topically. Corticosteroids have been implicated in the production of benign intracranial hypertension, which is paradoxical because they also are used in its treatment. The most important side effect of drugs such as chloroquine and hydroxychloroquine is an almost always irreversible maculopathy with resultant loss of central vision. Corneal and retinal changes similar to those caused by the quinolines have been reported with indomethacin, but there is some question about a cause and effect relationship. The National Registry of Drug Induced Ocular Side Effects in the US published 30 case histories of cataract suspected to be induced by allopurinol; numerous additional cases have been reported to the registry since. Phenothiazine, with an estimated 3% incidence of side effects, appears to be safer than other antipsychotic drugs, but the rate of ocular effects increases with the duration of therapy. Thioridazine and chlorpromazine are known to cause lens deposits and pigmentary retinopathy. There is a significantly high prevalence of thrombophlebitis and pseudotumor cerebri among women who use OCs and thrombotic retinal vascular disease, such as retinal vein occulsion, might be linked with them. It also is probable that, because of altered hydration of the cornea, there is a decreased tolerance to contact lenses.
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PMID:Drugs affecting the eye. 286 12

Iridoschisis is a rare condition of uncertain etiology characterized by a cleavage of the iris layers. We report four cases studied by fluorescein angiography to display possible occurrence of vascular abnormalities in the pathogenesis of the disease. Case 1: 80 year old woman with bilateral schisis of the peripheral iris, in the inferonasal quadrant in RE and inferotemporal in LE. A shallow anterior chamber was present in OU; IOP was 18 in RE and 15 in LE. No corneal abnormalities were present. Fluoroiridography showed a normal pattern filling of the iris vascularity, that was more visible in the schisis area. Case 2: 66 year old man with diabetes and open-angle glaucoma operated on for trabeculectomy five years previously. The examination showed a normal cornea, a shallow anterior chamber and miotic pupils for pilocarpine therapy. IOP was 12 in OU. The iridoschisis was present in RE in the lower sectors which were totally involved from the outer iris to the inner pupillary margin. Fluoroiridography indicated a normal vessel perfusion without any abnormality in the affected sectors. A slight bilateral pupillary dye leakage without any stromal diffusion was attributable to the patient's age. Case 3: 55 year old woman treated with miotics in RE for a glaucoma diagnosed after head trauma twenty years before, after which the vision in LE was reduced to 2/200 for post-traumatic optic nerve atrophy. No corneal abnormality was present. The anterior chamber was shallow and the ocular tension was 14 in RE and 10 in LE.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Fluoroiridographic aspects of iridoschisis]. 317 Oct 99

In the last five years, 500 one-eyed patients have undergone cataract surgery at the authors' hospital. A Simcoe-type posterior chamber lens was implanted in 425 of the eyes. An eye was defined as an only eye if corrected vision in the fellow eye was 1/60 or less, or better vision in cases of amblyopia. The main causes of loss of function in partner eyes were macular degeneration, amblyopia, and glaucoma. The rate of intraoperative and postoperative complications was the same as in the entire patient collective, and in absolute terms actually lower. There were four cases of intraoperative rupture of the posterior capsule (in two of which it subsequently proved possible to fit a posterior chamber intraocular lens (PCIOL], and one case each of corneal decompensation and excessive hemorrhage into the anterior chamber. PCIOLs were subsequently also implanted in both these eyes. Early postoperative complications included several cases of iris prolapse, all of which were easily rectified, and intermittent phases of endothelial decompensation associated with cornea guttata. In view of the low overall rate of intraoperative and postoperative complications, the authors advocate implantation of a PCIOL in remaining eyes with visual function, except those with proliferative retinopathies (primarily diabetes mellitus), pre-existing retinal detachments (particularly in young men with myopia and a history of detachment in the fellow eye), and unregulated glaucoma.
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PMID:[Cataract operations on the remaining eye]. 322 54

Diabetes mellitus can lead to blindness through its effects on the retina and lens, yet diabetes is a systemic disease influencing the entire eye. The current interest in extended wear contact lenses emphasizes the need for the practitioners to have a thorough knowledge of the pathophysiology of the anterior eye and cornea of the diabetic. The current literature is reviewed, and its relevance to contact lens wear is discussed.
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PMID:A review of manifestations of diabetes mellitus in the anterior eye and cornea. 328 72


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