Diabetic cataract

T.J. Lyons, G. Silvestri, J.A. Dunn, D.G. Dyer, and J.W. Baynes, Role of glycation in modification of lens crystallins in diabetic and non-diabetic senile cataracts, Diabetes, 1991, 40, 1010-1015. 

CS/DS Macular corneal dystrophy, glaucoma, cataract, retinal detachment/proliferative vitreoretinopathy, myopia, thyroid eye disease, pseudoexfoliation syndrome HS Glaucoma, cataract, diabetic retinopathy, retinal detachment/proliferative... 

HA Macular corneal dystrophy, glaucoma, cataract, diabetic retinopathy, retinal... 

Tolrestat (28) is a long-acang aldose reductase inhibitor useful in the prophylaxis of diabetic neuropathy, retinopathy, and cataracts [24 25] Lastly, the intro-ducuon of fluorine into steroids probably ushered in the modem era of fluonnated drugs Many commercial products were introduced [2] Typical of the products are the anti inflammatory glucocorticoids dexamethasone (29 X = F, Y = H), para-methasone (29, X = H, Y = F), and flumethasone (29, X = H, Y = F)... 

Calpain Tissue specific calpains have been implicated in diabetes, cataracts, multiple sclerosis, and limb-girdle muscular dystrophy type 2A. More than 50 inhibitors of calpain have described which have a potential for therapeutic applications. 

Fructose Sorbitol in the Lens Are Associated With Diabetic Cataract... 

Inhibitors of AR have been demonstrated to prevent a wide variety of biochemical, functional and structural alterations in animal models of diabetes. Early studies demonstrated arrest of both early cataract development and nerve conduction velocity. At least 30 clinical trials of AR inhibitors have been published involving nearly 1000 patients in total. However, there is little impressive data of their efficacy up to now but, rather than undermine the hypothesis linking excess polyol pathway activity to diabetic complications, it may reflect methodological difficulties and trial design errors. 

The same mechanism accounts for the cataracts in diabetics because aldose reductase also converts glucose to sorbitol, which causes osmotic damage. 

A 54-year-old man with type I (IDDM) diabetes is referred to an ophthalmologist for evaluation of developing cataracts. Pre-appointment blood work was requested and the results are shown below ... 

Diabetes mellitus can have serious secondary effects. A constantly raised blood sugar level can lead in the long term to changes in the blood vessels (diabetic angiopathy), kidney damage (nephropathy) and damage to the nervous system (neuropathy), as well as to cataracts in the eyes. 

Excessive activity of the enzyme aldose reductase sometimes accompanies diabetes. The net result is often accumulation of reduced sugars such as galactose in the lens of the eye and ensuing cataract formation. A1 restatin (43), an aldose reductase inhibitor, is one of the first agents found that holds promise of preventing diabetes-induced cataracts. The compound, actually used as its sodium salt, is prepared in straightforward manner by imide formation between 1,8-naphthalic anhydride (41) and glycine. ... 

The cataracts that can appear even in those diabetics whose disease is under control have been attributed to accumulation in the eye of sorbitol that results from the reduction of glucose by elevated levels of the enzyme aldose reductase that accompanies the disease. Inhibitors of that enzyme have been investigated as a means for controlling such cataracts. Known agents, as would be expected with enzyme inhibitors, tend to show marked differences in potency between optical isomers. The enantioselective synthesis of one of these compounds starts with the formation of an imine (12-3) of dihydrochromone (12-1) with the S form of the chiral... 

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