Protective function of alpha-tocopherol against the process of cataractogenesis in humans.
In a random trial 50 patients with unilateral/ bilateral idiopathic immature senile cataract (cortical n = 25, nuclear n = 25) requiring surgery at least in one eye were included in the present study. Reduced glutathione (GSH), vitamin E, malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) were studied in these patients receiving either vitamin E (n = 12 in each subgroup) or placebo (n = 13 in each group) for 30 days. A comparable increase of vitamin E in both types of lens homogenates of cataractous patients was observed in the study group. The level of GSH in cortical cataractous lenses in the study group was significantly raised (p < 0.001) whereas it was not increased significantly in nuclear cataractous lenses (p > 0.05) as compared to the placebo group. The percentage decrease in MDA levels was greater in cortical cataracts (38.07%) than in the nuclear type (27.94%). The activity of GSH-Px in cortical lenses was higher than that in the nuclear cataractous lens. The change in the size of lens opacity in cortical cataractous patients receiving vitamin E therapy was significantly decreased as compared to the placebo group. There may be a direct modulating effect of vitamin E on some GSH-related enzymes and the cortex of the lens might be protected more than the nucleus.
Seth
R K
RK
Department of Biochemistry, Postgraduate Institute of Medical Sciences, Rohtak, India.
Kharb
S
S
D000975:Antioxidants / Q000378:metabolism; D002386:Cataract / Q000473:pathology / Q000517:prevention & control*; D003315:Cornea / Q000473:pathology; D003318:Corneal Opacity / Q000473:pathology; D004032:Diet; D005260:Female; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008875:Middle Aged; D014810:Vitamin E / Q000097:blood / Q000627:therapeutic use*
D000975:Antioxidants; D014810:Vitamin E; D008315:Malondialdehyde; D005978:Glutathione